Volume 11 - 2024 | https://doi.org/10.3389/fsurg.2024.1519414 can lead to significant complications in orthopedic surgery(1) This case report presents a 57-year-old woman who developed gluteal tendinopathy and Trendelenburg gait two years after a total hip arthroplasty (THA) due to a retained drain fragment A less experienced surgeon encountered resistance during drain removal on the first postoperative day and applied excessive force but later presented with pain and gait disturbances Radiographic evaluation revealed the retained drain necessitating surgical removal and gluteus medius augmentation The patient subsequently underwent a structured rehabilitation program This case emphasizes the importance of careful drain management and collaborative patient-doctor decision-making to prevent such complications The use of drainage systems in orthopedic surgery remains a controversial yet common practice, primarily aimed at removing blood and seroma from the surgical field during the postoperative period (1). Although generally safe, drain removal occasionally poses challenges, particularly when resistance is encountered, as inexperienced surgeons may inadvertently leave a fragment behind (2) While cases of retained drains have been reported in various surgical fields (3–6), their long-term complications in orthopedic surgery are less frequently documented. Potential outcomes range from asymptomatic retention to severe issues like limited range of motion (ROM) and cartilage damage (7–11) This case report highlights an unusual complication: gluteal tendinopathy resulting in Trendelenburg gait due to a retained surgical drain fragment a scenario not previously reported in the literature This report underscores the critical need for meticulous drain management and postoperative evaluations to prevent similar outcomes with a body weight of 70 kg and a height of 165 cm underwent a total hip arthroplasty due to a left femoral neck fracture This surgical intervention involved the precise placement of a prosthetic implant to restore the functionality of the hip joint as well as a meticulous repair of the abductor mechanism to ensure proper hip stability and movement post-surgery To effectively manage the risk of postoperative hematoma formation a 16F Hemovac drain was strategically inserted beneath the fascia This drain serves to evacuate any excess blood or fluid that may accumulate in the surgical area thereby promoting a smoother recovery process and reducing the likelihood of complications The closure of the surgical site was performed by a less experienced surgeon albeit under the close supervision of a more seasoned surgical professional This collaborative approach not only aimed to enhance the surgical outcome but also provided an invaluable learning opportunity for the less experienced surgeon ensuring that the procedure was conducted with the highest standards of care and precision the patient was mobilized later that same day and her initial recovery trajectory appeared to be progressing without any notable issues the patient returned to the clinic for the routine removal of sutures The combination of inadequate imaging protocols and the high volume of patients in the outpatient clinic contributed to this unfortunate lapse allowing the complication to remain undetected and potentially complicating the patient's recovery journey (A) Initial postoperative radiograph showing misdiagnosed retained drain (limited view) (B) X-ray showing the retained drain fragment two years post-surgery This finding raises significant concerns regarding postoperative complications and the need for potential intervention to address the retained material and alleviate the patient's ongoing symptoms alleviating the potential for ongoing irritation and dysfunction In addition to the removal of the fragment the surgical team addressed the underlying tendinopathy at the tendon insertion site which is critical for restoring optimal function This was achieved through anchor augmentation a technique that enhances the stability of the tendon attachment and promotes healing The augmentation process involved the placement of anchors that secure the tendon more effectively to the bone facilitating a stronger and more durable repair Surgical findings of tendinopathy and retained drain fragment entangled in muscle fibers Appearance compatible with gluteal tendinopathy due to chronic irritation the patient was placed on a comprehensive six-week structured rehabilitation program This program is designed to promote recovery and improve flexibility in the affected area allowing for a gradual return to normal activities while minimizing the risk of re-injury The rehabilitation regimen includes targeted exercises and regular assessments to monitor progress and adjust the program as necessary for optimal recovery outcomes she reported significant improvement in mobility and resolution of Trendelenburg gait mild residual tendinopathy symptoms persisted Retained drain is a rare and preventable complication that can be stressful for the patient and the surgeon (9) Most surgeons prefer to explore and remove the retained drain due to concerns about malpractice this will require an additional risk of anesthesia and a new surgical procedure should the part of the drain retained in the patient be removed The question remains the subject of debate Different drain fixation methods have been suggested to minimize these preventable complications (9, 12) For a younger surgeon on the learning curve along with many environmental factors such as carelessness and fatigue To manage in review this complication effectively it is crucial to ensure proper fixation of the drain after closing the layers There are no controlled studies on managing retained drains in orthopedics and only a limited number of case examples exist the doctor's cooperation with the patient is essential in treatment management Limited examples in the literature indicate that drains retained in soft tissue are generally followed and drains retained in the joint may cause mechanical problems and may need to be removed this case highlights that extra-articular drains are not without issues either chronic irritation and delayed wound healing were caused by the internal drain which led the patient to return with pain and gait disturbances we report this case of gluteal tendinopathy causing Trendelenburg gait as a complication of the retained drain This case serves as a crucial reminder of the potential complications associated with retained drains can result in severe and lasting consequences such as chronic irritation of surrounding tissues The case emphasizes that timely detection and appropriate management of these complications could have significantly reduced their severity This underscores the vital importance of implementing postoperative imaging protocols and conducting comprehensive clinical evaluations to identify issues early on ultimately promoting better patient outcomes The complications observed in this case were exacerbated by the inexperience of the less experienced surgeon involved This situation highlights the essential role that senior surgeons play in the training and supervision of less experienced medical staff Their guidance is crucial in minimizing the risks associated with surgical procedures such as the careful application of force during the removal of drains and thorough intraoperative checks are consistently practiced to ensure patient safety and minimize the likelihood of complications The implementation of standardized protocols for drain management is essential This includes practices such as the trimming of drain tips to prevent obstruction and ensuring that all drains are completely removed before concluding a surgical procedure Such measures can significantly reduce the risk of drain retention and its associated complications The routine use of anteroposterior (AP) radiographs in the postoperative period is recommended to facilitate early detection of any abnormalities This proactive approach can help identify issues before they escalate into more serious complications Engaging in shared decision-making with patients is vital for effective management of complications By fostering open communication and ensuring that patients are well-informed about their options healthcare providers can enhance the overall quality of care and improve patient satisfaction This collaborative approach not only empowers patients but also promotes adherence to treatment plans ultimately leading to better health outcomes The patient expressed significant relief following the removal of the retained drain fragment reporting improved mobility and a reduction in pain the patient was frustrated by the delayed diagnosis attributing her prolonged discomfort and gait disturbance to unaddressed surgical complications she appreciated the clear communication and collaborative approach during the second surgical intervention and rehabilitation process The patient emphasized the importance of comprehensive follow-up care and detailed postoperative imaging noting that earlier identification of the retained drain fragment could have alleviated her symptoms sooner she is satisfied with her current condition and remains optimistic about the continued benefits of physiotherapy in managing residual tendinopathy This case highlights the need for vigilance in drain management and postoperative evaluations can lead to severe complications such as gluteal tendinopathy and Trendelenburg gait Adhering to standardized surgical protocols providing adequate training to less experienced surgeons and fostering collaborative decision-making are essential steps in improving patient outcomes The datasets presented in this article are not readily available because this is a case report. Requests to access the datasets should be directed to Selahaddin Aydemir,c2VsYWhhZGRpbmF5ZGVtaXJAZ21haWwuY29t Written informed consent was obtained from the individual(s) for the publication of any potentially identifiable images or data included in this article The author(s) declare that no financial support was received for the research The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest The authors declare that no Generative AI was used in the creation of this manuscript All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher Retained broken wound drains: a preventable complication PubMed Abstract | Crossref Full Text | Google Scholar PubMed Abstract | Crossref Full Text | Google Scholar A rare case of a blood clot masquerading as a retained surgical drain PubMed Abstract | Crossref Full Text | Google Scholar PubMed Abstract | Google Scholar Retained drains causing a bronchoperitoneal fistula: a case report PubMed Abstract | Crossref Full Text | Google Scholar Google Scholar Long-term sequelae of patients with retained drains in spine surgery Retained surgical drains in orthopedics: two case reports and a review of the literature PubMed Abstract | Crossref Full Text | Google Scholar Retained surgical drain after total knee arthroplasty: an eight-year follow-up: a case report Retained drain after anterior cruciate ligament surgery: a silent threat to an athlete’s career: a case report An unusual cause of knee pain 10 years after arthroscopy Retained broken outflow cannula recovered 6 years post-knee arthroscopy Gluteal tendinopathy: integrating pathomechanics and clinical features in its management Gluteal tendinopathy: a review of mechanisms Google Scholar Duymaz B and Erduran M (2025) Case Report: Trendelenburg gait caused by retained drain fragment: a rare complication of total hip arthroplasty Received: 29 October 2024; Accepted: 13 December 2024;Published: 6 January 2025 Copyright: © 2025 Aydemir, Aydin, Çeltik, Duymaz and Erduran. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) distribution or reproduction in other forums is permitted provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited in accordance with accepted academic practice distribution or reproduction is permitted which does not comply with these terms *Correspondence: Selahaddin Aydemir, c2VsYWhhZGRpbmF5ZGVtaXJAZ21haWwuY29t Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher 94% of researchers rate our articles as excellent or goodLearn more about the work of our research integrity team to safeguard the quality of each article we publish The following is a summary of “Intraperitoneal laparoscopic technique in trendelenburg position: an effective surgical method for pyelolithotomy and heminephrectomy in patients with horseshoe kidneys,” published in the October 2024 issue of Urology by Xiong et al Researchers conducted a retrospective study to assess the safety and feasibility of intraperitoneal laparoscopic surgery in Trendelenburg position (ILSTP) for patients with horseshoe kidneys (HSKs) They reviewed 3 patients with HSKs who underwent ILSTP between March 2021 and March 2024 About 2 patients with pelvi-ureteric junction obstruction and recurrent kidney stones received pyelolithotomy and pyeloplasty while 1 patient with a symptomatic nonfunctioning left moiety of an HSK underwent heminephrectomy The results showed a mean operating time of 114 ± 64.8 (44–172) minutes and an estimated blood loss of 63.3 ± 51.3 (20–120) ml The mean hospital stay was 3.3 ± 1.5 (2–5) days with no major intra- or post-operative complications The study concluded that ILSTP is a feasible and effective technique for pyelolithotomy Source: bmcurol.biomedcentral.com/articles/10.1186/s12894-024-01631-4 The latest articles and insights from your colleagues in your specialty(ies) of choice SUBSCRIBE NOW View all newsletters Insights from the leaders in medical research Subscribe to our free Newsletters to receive weekly emails and even get a laugh or two from our medical cartoons SUBSCRIBE NOW About Physician’s Weekly Careers Memberships & Verifications Advertise With Us Our Partners Blog Terms & Conditions Privacy Policy Editorial Policy Contact Us The content of this site is intended for healthcare professionals. Any views and opinions expressed are those of the author(s) and/or participants and do not necessarily reflect the views, policy, or position of Physician’s Weekly, their employees, and affiliates. A profile showcasing an individual's professional experience A profile for companies that LinkedIn users can follow In robot-assisted laparoscopic prostatectomy surgery patients are tilted 30°–40° head-down. Knowledge of cerebral autoregulation and determinants of cerebral blood flow in this setting is limited, though postoperative cognitive impairment has been reported. This observational study describes the hemodynamic determinants of cerebral blood flow and dynamics of cerebral perfusion pressure during surgery in the Trendelenburg position and the correlations with postoperative cognition measures. ICA flow and cerebral perfusion pressure were significantly reduced during robot-assisted laparoscopic prostatectomy surgery. ICA flow positively correlated with cardiac index and PaCO2, but negatively with mean arterial pressure. Postoperative cognitive function was not impaired. Volume 3 - 2024 | https://doi.org/10.3389/fanes.2024.1395973 Background: In robot-assisted laparoscopic prostatectomy surgery patients are tilted 30°–40° head-down Knowledge of cerebral autoregulation and determinants of cerebral blood flow in this setting is limited though postoperative cognitive impairment has been reported This observational study describes the hemodynamic determinants of cerebral blood flow and dynamics of cerebral perfusion pressure during surgery in the Trendelenburg position and the correlations with postoperative cognition measures Materials and methods: We included patients scheduled for robot-assisted laparoscopic prostatectomy without known cerebrovascular disease optic nerve sheath diameter as a surrogate for intracranial pressure ultrasound-measured internal carotid artery (ICA) blood flow and PaCO2 were recorded at six time points (awake Comprehensive cognitive tests were performed before surgery and 10 and 180 days post-surgery Data was evaluated using linear regression models Results: Forty-four males with a mean age of 67 years were included Duration of anesthesia was 226 min [IQR 201,266] with 165 min [134,199] in head-down tilt ICA flow decreased after induction of anesthesia (483 vs 344 ml/min) and remained lowered before increasing at return to horizontal position (331 vs Cerebral perfusion pressure decreased after 1 h tilt (from 73 to 62 mmHg) and remained lowered (66 mmHg) also after return to horizontal position Optic nerve sheath diameter increased from mean 5.8 mm to 6.4 mm during the course of surgery ICA flow correlated positively with cardiac index (β 0.367 1 L/min/m2 increase corresponding to 92 ml/min increased ICA flow) PaCO2 had a positive effect on ICA flow (β 0.145 1 kPa increase corresponding to 49 ml/min increased ICA flow) while mean arterial pressure had a negative effect (β −0.203 10 mmHg increase corresponding to a 29 ml/min decline in ICA flow) We found no evidence of postoperative cognitive dysfunction Conclusion: ICA flow and cerebral perfusion pressure were significantly reduced during robot-assisted laparoscopic prostatectomy surgery ICA flow positively correlated with cardiac index and PaCO2 but negatively with mean arterial pressure Postoperative cognitive function was not impaired any long-term effects of prolonged Trendelenburg positioning on cognitive function have yet to be determined monitoring cerebral blood flow changes peroperatively may be not clinically relevant if not evaluated together with patient-centered outcomes like long-term cognitive function To optimize perioperative care of an increasingly elderly surgical population it is important to assess postoperative cognitive dysfunction and its possible connections to changes in intracranial pressure and cerebral blood flow during surgery This observational study aimed to investigate the changes in cerebral circulatory physiology during robot-assisted laparoscopic prostatectomy and describe the determinants of cerebral blood flow we wanted to compare the effects of cardiac output and mean arterial pressure on cerebral blood flow we employed a comprehensive state-of-the-art cognitive testing with a substantial follow-up time to detect whether cognition was impaired following surgery The study was designed as a prospective, non-randomized observational study. We invited all patients who were scheduled for robot-assisted laparoscopic prostatectomy surgery at Akershus University Hospital from June 10th to December 23rd, 2022. Patients who met the exclusion criteria listed in Supplementary Table S1 were not included written consent was obtained before the first presurgical cognitive test Our recruitment process and protocol were in accordance with the Declaration of Helsinki and approved by the Regional Ethics Committee (Oslo No.: 230764) and the Institutional Data Protection Officer (ref and postoperative analgesia were given according to our department's standard regime for robot-assisted laparoscopic prostatectomy Oral premedication was given approximately 60 min before surgery 1.5 g if age ≥75 years or weight ≤60 kg) 12 mg if age ≥75 years or weight ≤60 kg) prolonged release formulation (10 mg 5 mg if age ≥75 years or weight ≤60 kg) Dexamethasone was omitted in patients with diabetes mellitus unless they were deemed well-regulated with HbA1C ≤ 48 mmol/mol or had type II diabetes regulated by low-dose metformin (500 mg × 2–3/day) or managed by dietary restrictions alone remifentanil and propofol using target control anesthesia Muscle relaxation was provided using rocuronium (0.6 mg/kg) Anesthesia was maintained with an infusion of propofol and remifentanil Bolus doses of rocuronium were used to maintain deep neuromuscular blockade throughout the procedure (TOF = 0 and PTC ≤4) Sugammadex was used as reversal agent if TOF < 90% at the end of surgery Bolus doses of ephedrine 5–10 mg i.v and phenylephrine 0.05–0.1 mg i.v was administered approximately 30 min before extubation unless contraindicated was administered to patients with a high risk of developing postoperative nausea and vomiting Normovolemia was maintained with an infusion of isotonic Ringer's Acetate with a rate of 3 ml/kg Protocol for measurement time points and associated patient conditions Standard anesthesia monitoring for the procedure included an arterial catheter for continuous blood pressure measurements finger pulse oximetry and measurements of end-tidal CO2 and mean airway pressure from the ventilator circuit (Zeus Results from arterial blood gas analyses collected for study purposes were concealed from the treating anesthesia team if values did not exceed predetermined safety thresholds (Supplementary Table S2) Central venous pressure was measured through a short 1.1 mm diameter cannula placed in the left external jugular vein (20) Standard breath-to-breath spirometry from the ventilator circuit provided tidal volumes USA) continuously measured and displayed intraabdominal pressure The degree of tilt of the operating table was electronically controlled and displayed on the table panel Doppler ultrasound measurements were obtained using a high-frequency linear probe over the right internal carotid artery (ICA) (VenueTM We obtained time-averaged mean frequency (TAMEAN) and luminal cross-sectional area in both systole and diastole All ultrasound measurements were repeated 3 times at each measurement time point (T1-T6) the ventilator frequency was set to a minimum of 15 breaths per minute during the recording to ensure that the ultrasound measurements included a full ventilatory cycle The ventilation frequency was returned to their prior setting as soon as ultrasound measurements were completed Arterial line signals were analyzed using LiDCO RapidTM (Masimo Corporation) Optic nerve sheath diameter (ONSD) was measured using ultrasound after induction of anesthesia (T2) and near the end of surgery (T5) We measured ONSD in the transverse and sagittal plane in both eyes Data was collected and stored using an electronic database (REDCap® Cognitive testing was performed using the Cambridge Neuropsychological Test Automated Battery (CANTAB®) (Cambridge Cognition Ltd) software, which tests different domains of cognitive function (attention, memory, visuo-spatial processing, language and executive functions) (21) Testing was performed at least one day before surgery and repeated approximately 10 and 180 days after surgery Cognitive testing was performed in a controlled and quiet environment at our hospital or at a healthcare facility closer to the patient's residence The principal investigator or dedicated research staff had oversight over the entire test routine to ensure proper execution and standardization of testing conditions Both the principal investigator and the research staff had received training from a neuropsychiatrist A total of 11 cognitive variables from the testing were analyzed We analyzed Motor Screening Task Mean Latency Paired Associates Learning First Attempt Memory Score Paired Associates Learning Total Errors Adjusted Reaction Time Task Median Five-Choice Reaction Time Rapid Visual Information Processing Median Response Latency Rapid Visual Information Processing Probability of False Alarm Spatial Working Memory Between Errors and Spatial Working Memory Strategy Variables were chosen based on recommendations from the CANTAB Connect Research: Test Administration User Guide (22), recommendations from the CANTAB® team and review of previous studies using CANTAB® to test for postoperative cognitive dysfunction (21, 23) Our primary endpoints were changes in ICA flow ONSD and postoperative changes in the cognitive testing variables Secondary endpoints were correlations between ICA flow and other hemodynamic variables For time-averaged mean frequency and ICA cross-sectional area in systole and diastole the median value of all three measurements at each time point was used the median value of the ONSD for all four measurements was used ICA flow (ml/min) was calculated by multiplying the median time-averaged mean frequency (cm/sec) by the average cross-sectional area (cm2) of the internal carotid artery (median diastolic area · 0.67 + median systolic area · 0.33) Cerebral perfusion pressure was calculated by subtracting the central venous pressure from mean arterial pressure Cardiac index was calculated as cardiac output/body surface area Ideal body weight (kg) was calculated as patient height in cm – 100 The study was by design a non-randomized prospective observational study No formal sample size calculation was performed cardiorespiratory variables and outcomes from cognitive testing were assessed using a linear mixed model analysis fit by REML with t-tests using Satterthwaite's method Participant ID was set as the random effect to account for inter-subject correlation and measurement time was set as the fixed effect Independent variables potentially associated with changes in ICA flow in the timeframe T2–T6 were analyzed in a linear mixed model They were chosen a priori and included age and tidal volume divided by ideal body weight Partial pressure of arterial oxygen (PaO2) was not used in this analysis as we deemed it heavily influenced by pre-oxygenation before induction and extubation A forward stepwise regression procedure set to minimize BIC was run to select important predictors These were subsequently included in a linear mixed model with participant ID as a random effect The underlying relationships among the contributing variables were also integrated in a Structural Equation Model (SEM) and presented as a path diagram We performed a linear mixed model analysis for variables potentially associated with changes in cognitive outcomes modeling the variation in each endpoint with time as a fixed effect the first cognitive test as a reference point we performed a mixed model regression including the following fixed effects: Total tilt time the integral of cerebral perfusion pressure between T3 and T5 the integral of ICA flow between T3 and T5 the time between T2 and T6 (corresponding to the duration of anesthesia) The assumptions of normal distribution and equal variance were assessed using quantile-quantile plots and a frequency distributions test Normally distributed data are reported as means with 95% confidence interval shown in round brackets (x-y) and otherwise as medians and quartiles shown in square brackets [x,y] The analyses were considered exploratory in nature and therefore claims of significance are made cautiously Statistical analyses were performed using dedicated statistical software (R Foundation for statistical Computing using the “lmer” package for linear mixed models and “lavaan” for Structural Equation Modeling distributions and preparation of figures were done using JMP (JMP Pro17 ® Eighty-four males were screened for eligibility Of the 40 patients who were screened but not enrolled 17 were excluded due to logistical reasons and nine were excluded as they had a non-Scandinavian language as their native language Nine did not consent to participate or failed to respond to contact from the principal investigator Five were excluded due to known cerebrovascular or carotid disease No patient was excluded because of findings of carotid stenosis after enrollment we performed intraoperative recordings on 37 the remaining seven undergoing cognitive testing only Of the patients undergoing cognitive testing only five were excluded from intraoperative measuring due to logistical reasons The remaining two patients were excluded due to intraoperative complications the other due to subcutaneous emphysema affecting the neck Of the 37 patients who had intraoperative measurements Reasons for incomplete follow-up were logistical reasons (n = 4) failure to respond to contact (n = 3) or illness/surgical complications hindering cognitive testing (n = 5) The mean age of the included patients was 67 years (65–69), mean BMI was 27 kg/m2 (26–28) and median ASA physical status was 2 [2,2]. The most prevalent co-morbidities were hypertension (43%), coronary artery disease (16%), and diabetes mellitus (7%). Sixty-one percent had other co-morbidities. Supplementary Table S3 provides additional patient characteristics The total time with head-down tilt during surgery was 165 min [134,199] the duration of operation was 182 min [161,225] while general anesthesia lasted 226 min [201,266] The total propofol and remifentanil doses were 4.9 mg/kg/h [4.5 5.3] and 0.16 µg/kg/min [0.14 Vasopressors were used in 78% of patients at T3 Body temperatures were 36.2 C° [35.7 36.9] at the start and end of the surgery respectively Descriptive statistics and results of a linear mixed model of variation of observed peroperative variables with time are presented in Tables 2, 3 There was a significant approximately 30% decline in ICA flow after induction of anesthesia and onset of mechanical ventilation In the period from established head down tilt to end of surgery we observed no further changes in ICA flow but there was a moderate increase in ICA flow when the patients were tilted back to horizontal position Changes in peroperative physiological variables Cerebral perfusion pressure declined significantly following induction of anesthesia and did not change further immediately upon tilting. However, at all following timepoints cerebral perfusion pressure was lowered compared to immediately after tilting (Tables 2, 3) ONSD increased significantly over the course of the surgery We observed a significant decrease in ICA cross-sectional area from the awake state to after induction of anesthesia, with no significant changes in any of the subsequent time points. Similarly, blood velocity (time-averaged mean frequency) decreased 23% following induction of anesthesia, with no further changes apart from a trend towards recovery. Figure 1 provides an overview of changes in hemodynamic variables during surgery Overview of peroperative physiological changes Peroperative variables at different stages of robot-assisted laparoscopic prostatectomy in 37 males Values are means and 95% confidence intervals T5: immediately before end of head-down tilt partial pressure of arterial carbon dioxide; SVI Cardiac index and mean arterial pressure were the predictors of ICA flow selected in the forward stepwise regression procedure set to minimize BIC In a final multivariate linear mixed model cardiac index was the strongest predictor of ICA flow Its positive association had a log worth of 4.82 (p < 0.0001) more than twice the 2.30 log worth (p < 0.0005) of the negative association between mean arterial pressure and ICA flow the predicted ICA flow response to changes in cardiac index and mean arterial pressure is illustrated for each individual and on a group level based on mixed-model multiple regression Associations between internal carotid artery flow blood flow Data from 37 males undergoing robot-assisted laparoscopic prostatectomy Blue regression lines show individual patients’ change in ICA flow; black regression lines represents the overall group response with a 95% confidence fit for the slope Upper panel: Relationship between ICA flow and cardiac index 1 L/min/m2 increased cardiac index corresponding to 92 ml/min increased ICA flow Lower panel: Relationship between ICA flow and mean arterial pressure 10 mmHg increased mean arterial pressure corresponding to a decline in ICA flow of 29 ml/min Structural Equation Modeling also found ICA flow to have a significant positive relationship with cardiac index and PaCO2, while having a significant negative relationship with mean arterial pressure (Figure 3) The general structural equation model had a moderate fit (Chi-Squared/df = 8.995 the analysis potentially being limited by heterogeneity due to unaccounted-for variation in time present in the data The proportion of variance of ICA flow not explained by the effect of other variables was 0.83 Determining factors of blood flow and their underlying relationships Structural equation model of relationships between internal carotid artery flow airway pressure and partial pressure of CO2 in the arterial blood Arrows indicate regression effects and directions of how one variable affect another Red numbers indicate a negative relationship and blue numbers indicate a positive relationship between variables Double-headed arrows represent variances in the unit of the variable not explained by relations to other variables ***: p < 0.0001 **: p < 0.01 Focus and outcomes of the employed cognitive tests are shown in Table 4 We observed improvements 10 days after surgery in Rapid Visual Information Processing (1.1% p = 0.015) and Motor Screening Task Mean Latency 10.7% and at 180-days for Rapid Visual Information Processing (2.2% Motor Screening Task Mean Latency (10.8% Reaction Time Task Median Five-Choice Reaction Time (4.3% p = 0.003) and Spatial Working Memory Between Errors (28% Total time spent under anesthesia and total Trendelenburg time were respectively negative and positive predictors of Spatial Working Memory Strategy, but these results should be interpreted with a high degree of caution considering the large number of tests and exploratory nature of the analysis. Data are presented in Supplementary Table S4 The main findings in this observational study of patients undergoing robot-assisted laparoscopic prostatectomy surgery were a significant decline in ICA flow and cerebral perfusion pressure after induction of anesthesia a further reduction in cerebral perfusion pressure was found after one hour in Trendelenburg position There was a significant increase in optic nerve sheath diameter (ONSD) in the head-down tilted position indicating an increase in intracranial pressure ICA flow showed a moderate positive association to cardiac index and to a smaller degree with PaCO2 a negative association was found between ICA flow and mean arterial pressure There were slight improvements in some cognitive testing outcomes after 10 and 180 days none of the variables observed during surgery predicted cognitive outcomes with certainty in their study PaCO2 was actively held between 30 and 35 cmH2O and a decrease in cardiac index was observed over time In the present study ICA flow was positively correlated to cardiac index but also to PaCO2 which increased during surgery from 5.6 kPa (42 mmHg) concur with the findings in the present study intrathoracic pressure will increase because of the abdominal content shift during head-down tilt increasing central venous pressure with a concomitant increase in hydrostatic venous pressure on the brain This changes the relationship between hydrostatic and osmotic pressures in the brain An increase in extracellular fluid will occur and over time institute cerebral edema In patients undergoing robot-assisted laparoscopic prostatectomy, intracranial pressure estimated by the zero flow pressure method, calculated from transcranial doppler velocity measurements, showed a close relationship between cerebral perfusion pressure calculated as mean arterial pressure minus central venous pressure and mean arterial pressure-estimated intracranial pressure by the Belfort formula (8) even after extended time spent in the Trendelenburg position Reducing mean airway pressures either by reducing positive end-expiratory pressure or tidal volumes may reduce intracranial pressure in the head-down tilted patient positive end-expiratory pressure during tilt was moderate (8 mBar) and tidal volumes were low (6 ml/kg Ideal body weight) values varied markedly between individuals during tilting central venous pressure ranging from 10 to 28 mmHg and cerebral perfusion pressure from 49 to 99 mmHg With the patient under general anesthesia, subjected to pneumoperitoneum and in the Trendelenburg position we found a significant positive association between cardiac index and cerebral blood flow, with a moderate effect size. Although this association has previously been described in both anesthetized and non-anesthetized individuals in the supine or anti-Trendelenburg position (16, 17) it is a novel finding for patients in the Trendelenburg position This underscores the importance of optimizing patients’ cardiac output during surgery The major difference between those and the present study is the utilization of the extreme Trendelenburg position limiting the effects of hydrostatic pressure in the brain While a large variation in older adults’ ability to autoregulate cerebral blood flow during changes in blood pressure has been demonstrated (35), cerebral autoregulation has been found to be mostly intact during propofol and remifentanil anesthesia when maintaining normal PaCO2 (36). However, hypercapnia during anesthesia increases cerebral CO2 reactivity (33) We found ICA flow to be positively associated with PaCO2 an increase of 1 kPa CO2 corresponding to an increase in ICA flow of 49 ml/min A decline in PaCO2 would however also reduce the hydrostatic pressure of the cerebral capillary system potentially reducing the risk of cerebral oedema Previous studies showing postoperative cognitive dysfunction following robot-assisted laparoscopic prostatectomy performed their testing one to seven days post-surgery (4, 5, 39). Two of the studies reported a correlation between intraoperative pulsatility index and ONSD, surrogate markers for intracranial pressure, and incidence of postoperative cognitive dysfunction (4, 5) Our data suggests a complete return to baseline cognition before the 10-day mark and sustained cognitive abilities in patients tested at the 180-day mark despite major changes in intracranial pressure cerebral blood flow and cerebral perfusion pressure during robot-assisted laparoscopic prostatectomy surgery We further found no consistent correlation between any of the cognitive outcomes and any data recorded during surgery they only supply 80% of the cerebral blood flow the remainder coming from the vertebral arteries Our study utilized unilateral measurements of the ICA since the contralateral side was used for central venous pressure measurements Vasopressors were not administered by protocol but at the discretion of the attending doctor or nurse anesthetist The choice to exclude non-Scandinavian native language speakers due to the cognitive testing may limit external validity the first cognitive test was performed only days before surgery when the cancer diagnosis and anticipation of surgery may have contributed negatively to the results Selection bias may have played a role at the 180-day testing as we had a substantial loss to follow up This observational study may have been underpowered for statistical analyses of cognitive test results This study demonstrated that ICA flow and cerebral perfusion pressure in patients undergoing robot-assisted radical prostatectomy decrease significantly after induction of anesthesia No further decline in ICA flow was observed after application of pneumoperitoneum or head down tilt to 30 degrees despite cerebral perfusion pressure continuing to decline ICA flow was strongly positively predicted by changes in cardiac index and PaCO2 while the correlation between ICA flow and mean arterial pressure was slightly negative To prevent reduced cerebral blood flow during surgery in the Trendelenburg position monitoring of patients’ cardiac output seems more important than the traditional sole focus on mean arterial pressure No apparent decline in cognitive test results were observed 10 and 180 days after surgery Data were used under license for the current study and so are not publicly available further inquiries can be directed to the corresponding author The studies involving humans were approved by Regional Ethics Committee (Oslo The studies were conducted in accordance with the local legislation and institutional requirements The participants provided their written informed consent to participate in this study The author(s) declare financial support was received for the research The project was funded by the South-Eastern Norway Regional Health Authority (Grant no We thank senior consultant of urological surgery Gunder Magne Lilleaasen and nurse anesthetist Gitte Lise Olsen for assistance in planning the logistics of the study and specialist nurse Mette Bach for her assistance in data collection and patient logistics We greatly appreciate the included patients’ willingness to contribute to the study The Supplementary Material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fanes.2024.1395973/full#supplementary-material partial pressure of arterial carbon dioxide; TAMEAN Motor Screening Task Mean Latency; PALFAMS Paired Associates Learning First Attempt Memory Score; PALTEA Paired Associates Learning Total Errors Adjusted; RTIFMDRT Reaction Time Task Median Five-Choice Reaction Time; RVPA Rapid Visual Information Processing A; RVPMDL Rapid Visual Information Processing Median Response Latency; RVPPFA Rapid Visual Information Processing Probability of False Alarm; SWMBE Spatial Working Memory Between Errors; SWMS The implementation of robotic surgery in Israel PubMed Abstract | Google Scholar Trends in the adoption of robotic surgery for common surgical procedures Comparison of robot-assisted radical prostatectomy and open radical prostatectomy outcomes: a systematic review and meta-analysis Relationship between middle cerebral artery pulsatility index and delayed neurocognitive recovery in patients undergoing robot-assisted laparoscopic prostatectomy Effects of pneumoperitoneum and steep trendelenburg position on cerebral hemodynamics during robotic-assisted laparoscopic radical prostatectomy: a randomized controlled study Transient but significant visual field defects after robot-assisted laparoscopic radical prostatectomy in deep Trendelenburg position Effects of positive end-expiratory pressure on intracranial pressure during pneumoperitoneum and trendelenburg position in a porcine model Cerebral haemodynamic physiology during steep trendelenburg position and CO(2) pneumoperitoneum Influence of steep trendelenburg position and CO(2) pneumoperitoneum on cardiovascular and respiratory homeostasis during robotic prostatectomy Perioperative neurocognition in elderly patients PubMed Abstract | Crossref Full Text | Google Scholar Effect of pneumoperitoneum and trendelenburg position on internal carotid artery blood flow measured by ultrasound during robotic prostatectomy Regulation of cerebral blood flow in humans: physiology and clinical implications of autoregulation Cerebral blood flow and oxygen consumption in man PubMed Abstract | Crossref Full Text | Google Scholar Regulation of cerebral autoregulation by carbon dioxide PubMed Abstract | Crossref Full Text | Google Scholar Cerebral versus systemic hemodynamics during graded orthostatic stress in humans Internal carotid artery blood flow in healthy awake subjects is reduced by simulated hypovolemia and noninvasive mechanical ventilation Internal carotid artery blood flow response to anesthesia and head-up tilt during laparoscopic cholecystectomy Time course of cerebrovascular autoregulation during extreme trendelenburg position for robotic-assisted prostatic surgery Comparing the effect of positioning on cerebral autoregulation during radical prostatectomy: a prospective observational study Comparison of external jugular and central venous pressures in mechanically ventilated patients The international ENIGMA-II substudy on postoperative cognitive disorders (ISEP) CANTAB Connect Research: Admin Application User Guide V 1.25 (2022) Google Scholar Lower extremity artery disease and cognitive impairment Crossref Full Text | Google Scholar Regional cerebral blood flow and glucose metabolism during propofol anaesthesia in healthy subjects studied with positron emission tomography Ultrasonic measurement of optic nerve sheath diameter: a non-invasive surrogate approach for dynamic real-time evaluation of intracranial pressure Increase in intracranial pressure during carbon dioxide pneumoperitoneum with steep trendelenburg positioning proven by ultrasonographic measurement of optic nerve sheath diameter The effect of robotic surgery on intraocular pressure and optic nerve sheath diameter: a prospective study Comparison of the effects of desflurane and total intravenous anesthesia on the optic nerve sheath diameter in robot assisted laparoscopic radical prostatectomy: a randomized controlled trial Effects of increased optic nerve sheath diameter on inadequate emergence from anesthesia in patients undergoing robot-assisted laparoscopic prostatectomy: a prospective observational study Optic nerve sheath diameter remains constant during robot assisted laparoscopic radical prostatectomy Quantification of optic nerve and sheath diameter by transorbital sonography: a systematic review and metanalysis Normal age- and sex-related values of the optic nerve sheath diameter and its dependency on position and positive End-expiratory pressure Influence of blood pressure on internal carotid artery blood flow during combined propofol-remifentanil and thoracic epidural anesthesia Internal carotid artery blood flow is enhanced by elevating blood pressure during combined propofol-remifentanil and thoracic epidural anaesthesia: a randomised cross-over trial Individual variability of cerebral autoregulation posterior cerebral circulation and white matter hyperintensity PubMed Abstract | Crossref Full Text | Google Scholar Evidence of practice effect in CANTAB spatial working memory test in a cohort of patients with mild cognitive impairment Test-retest reliability analysis of the Cambridge neuropsychological automated tests for the assessment of dementia in older people living in retirement homes Comparison of cognitive function after robot-assisted prostatectomy and open retropubic radical prostatectomy: a prospective observational single-center study Søvik S and Hyldebrandt JA (2024) Predictors of cerebral blood flow during surgery in the Trendelenburg position and their correlations to postoperative cognitive function Received: 4 March 2024; Accepted: 14 August 2024;Published: 29 August 2024 Copyright: © 2024 Nordum, Tveit, Idland, Øyen, Thomas, Søvik and Hyldebrandt. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) *Correspondence: Signe Søvik, c2lnbmUuc292aWtAbWVkaXNpbi51aW8ubm8= Metrics details We aim to explore the effect of head-down position (HDP) in moderate anterior circulation stroke patients with probable large artery atherosclerosis (LAA) etiology multi-center and phase-2 trial was conducted in China and completed in 2021 Eligible patients were randomly assigned (1:1) into the HDP group receiving −20° Trendelenburg or control group receiving standard care according to national guideline The primary endpoint was proportion of modified Rankin Scale (mRS) of 0 to 2 at 90 days which is a scale for measuring the degree of disability after stroke 90-day mRS was assessed by a certified staff member who was blinded to group assignment A total of 96 patients were randomized (47 in HDP group and 49 in control group) and 94 (97.9%) patients were included in the final analysis: 46 in HDP group and 48 in control group The proportion of favorable outcome was 65.2% (30/46) in the HDP group versus 50.0% (24/48) in the control group (unadjusted: OR 2.05 [95%CI 0.87-4.82] No severe adverse event was attributed to HDP procedures This work suggests that the head-down position seems safe and feasible but does not improve favorable functional outcome in acute moderate stroke patients with LAA This trial was registered with ClinicalTrials.gov blinded-endpoint trial to explore the effect of HDP in moderate AIS patients with LAA who were not eligible for intravenous thrombolysis or endovascular therapy This figure shows the overall patient flow in the trial The median duration of position intervention within 24 h was 15.0 h (IQR 12.0–16.0) and the median duration of each intermittent HDP was 35.0 minutes (IQR 30.0–60.0) the side-lying position was used in 26.1% (12/46) patients to prevent possible aspiration 1 = symptoms without clinically significant disability Source data are provided as a Source Data file Adverse events are reported in Table 4 There were eight HDP-related adverse events: five patients reported headaches but these AEs resolved after adjusting the patient to the horizontal position without any further medical treatment There was no difference in asymptomatic intracranial hemorrhage the occurrence of stroke and cardiovascular events and stroke-associated pneumonia between the two groups we investigated the effect of HDP (−20°) on functional outcomes in acute moderate ischemic stroke patients with probable LAA We found that treatment with HDP for 2 weeks applied as an adjunct to guideline-based medical management was safe and did not improve the primary outcome (mRS 0–2 at 90 days) when compared with guideline-based medical management alone HDP may have an improved effect on major secondary outcomes including excellent functional outcome (mRS 0–1) ordinal shift distribution of mRS at 90 days ~80% of enrolled patients harbored severe stenosis or vessel occlusion This subgroup of patients is most vulnerable to stroke progression or recurrence associated with hypoperfusion mechanisms and hence may derive greater benefit from the head-down position we found a significant mRS improvement at 90 days in the HDP group vs the control group as well as improvement in NIHSS from baseline to day 12 We also observed a significant improvement in the proportion of mRS scores 0–1 at 90 days in the HDP group there was no difference in mortality between the two groups these results support the safety and potentially improved neurological outcomes with HDP in patients with acute moderate ischemic stroke with LAA in a Chinese population only a few patients reported uncomfortable symptoms which resolved after adjusting to a horizontal position without any medical treatment The strength of this study is the randomized multicenter design to determine the safety and possible efficacy of HDP in acute moderate ischemic stroke patients with probable LAA etiology These promising results may promote further trials to investigate the effect of HDP in a broader array of AIS patients patients who develop early neurological deterioration due to hypoperfusion mechanisms We acknowledge several limitations to our study The main limitation is the relatively small sample due to the pilot nature which makes the conclusion exploratory and subgroup analysis such as the effect of site on primary outcome the open-label design may have resulted in bias although we used blinded evaluation at 90 days to mitigate this potential bias excluding patients who received thrombolysis or thrombectomy introduce selection bias and may limit the generalizability of our results the neuroimaging infarct or penumbra size was not determined in detail in the pilot study there was no limit of head position in the control group in this trial but we did not record the actual head position in the control group during the trial especially within 24 h after randomization This detailed information would be important to understand the effect of different head positions on stroke outcomes this randomized clinical trial suggests that in patients with acute moderate ischemic stroke with large artery atherosclerosis the head-down position seems safe and feasible but does not improve 90-day favorable functional outcome as a primary outcome although a direction of benefit was present with the potential to improve secondary outcomes multicenter trial is warranted to confirm these findings and approved by the ethics committees of the General Hospital of Northern Theater Command (former General Hospital of Shenyang Military Region Fukuang General Hospital of Liaoning Health Industry Group the Traditional Medicine Hospital of Dalian Lvshunkou Central Hospital affiliated to Shenyang Medical College Signed informed consents were obtained from the patients or their legally authorized representatives eligible patients were randomly assigned (1:1) using a computer-generated randomization sequence with a block size of four and sealed envelopes into either HDP group receiving Trendelenburg as an adjunct to guideline-based medical management or a control group only receiving guideline-based medical management The final 90-day mRS was evaluated by one qualified personnel who was blinded to treatment allocation according to a standardized procedure manual in each study center Central adjudication of clinical and safety outcomes was also conducted by assessors unaware of treatment allocation or clinical details patients were positioned to −20° Trendelenburg position from 8:00 a.m the patients were continuously monitored by ECG and blood oxygen saturation If the patients could not tolerate this position they were then adjusted slowly to a horizontal position for 10 to 30 min The repositioning could be repeated during HDP treatment patients were placed in a −20° Trendelenburg position with 1 to 1.5 h duration three times a day The treatment procedure lasted for 10 to 14 days the side-lying position with −20° Trendelenburg was allowed if there was a high risk of aspiration suspected by local providers patients were treated according to the AHA/ASA 2018 guidelines for the early management of ischemic stroke without any intervention of head position (supine or sitting position determined by local investigator) secondary outcomes included mRS score 0–1 at 90 days change in NIHSS score at day 12 compared with baseline the occurrence of stroke or other vascular events END was defined as ≥4 point increase in NIHSS score within 48 h but was not a result of intracerebral hemorrhage (Supplementary Methods in Supplementary information) Prespecified safety outcomes included any adverse events and serious adverse events during HDP which were not present at the beginning of the study Adverse events with HDP were adjudicated by the chairman of the data safety monitoring board (YLW) Analyses were done using the statistical software IBM SPSS Statistics 24 This trial of HOPES2 was registered with ClinicalTrials.gov with the number NCT03744533 on November 16 and is now closed at all participating sites Further information on research design is available in the Nature Portfolio Reporting Summary linked to this article Guidelines for the early management of patients with acute ischemic stroke: 2019 update to the 2018 guidelines for the early management of acute ischemic stroke: a guideline for healthcare professionals from the American Heart Association/American Stroke Association Head positioning in suspected patients with acute stroke from prehospital to emergency department settings: a systematic review and meta-analysis Cerebral haemodynamics with head position changes post-ischaemic stroke: a systematic review and meta-analysis Head position and cerebral blood flow velocity in acute ischemic stroke: a systematic review and meta-analysis crossover trial of head positioning in acute stroke Head position in the early phase of acute ischemic stroke: an international survey of current practice The effect of head positioning on cerebral hemodynamics: experiences in mild ischemic stroke Flat-head positioning increases cerebral blood flow in anterior circulation acute ischemic stroke Heads down: flat positioning improves blood flow velocity in acute ischemic stroke Effects of body position on intracranial pressure and cerebral perfusion in patients with large hemispheric stroke Stroke volume of the heart and thoracic fluid content during head-up and head-down tilt in humans Risk of pneumonia associated with zero-degree head positioning in acute ischemic stroke patients treated with intravenous tissue plasminogen activator Kölegård R., Da S. C., Siebenmann C., Keramidas M. E., Eiken O. Cardiac performance is influenced by rotational changes of position in the transversal plane, both in the horizontal and in the 60̊ head-up postures. Clin. Physiol. Funct. Imaging https://doi.org/10.1111/cpf.12520 (2018) The Trendelenburg position: a review of current slants about head down tilt Thomas Willis lecture: targeting brain arterioles for acute stroke treatment The effect of head-down tilt in experimental acute ischemic stroke.Eur Zhao Z. A. et al. Effect of head-down tilt on clinical outcome and cerebral perfusion in ischemic stroke patients: a case series. Front Neurol. https://doi.org/10.3389/fneur.2022.992885 (2022) Optical bedside monitoring of cerebral blood flow in acute ischemic stroke patients during head-of-bed manipulation No benefit of flat head positioning in early moderate-severe acute ischaemic stroke: a HeadPoST study subgroup analysis The relationship between widespread changes in gravity and cerebral blood flow Treatment effect of intravenous thrombolysis bridging to mechanical thrombectomy on vessel occlusion site Collateral blood vessels in acute ischaemic stroke: a potential therapeutic target Classification of subtype of acute ischemic stroke Definitions for use in a multicenter clinical trial Trial of Org 10172 in acute stroke treatment Relationship between stroke etiology and collateral status in anterior circulation large vessel occlusion Endovascular treatment after stroke due to large vessel occlusion for patients presenting very late from time last known well Preventive antibacterial therapy in acute ischemic stroke: a randomized controlled trial Dysphagia screening and risks of pneumonia and adverse outcomes after acute stroke: an international multicenter study Autonomic cardiovascular adaptations to acute head-out water immersion Chinese stroke association guidelines for clinical management of cerebrovascular disorders: executive summary and 2019 update of clinical management of ischaemic cerebrovascular diseases Download references This study was funded by grants from the National Natural Science Foundation of the Peoples Republic of China (8207147) and the Science and Technology Project Plan of Liao Ning Province (2018225023 and 2019JH2/10300027) General Hospital of Northern Theater Command The Traditional Medicine Hospital of Dalian Lvshunkou designed the study and critically revised the manuscript All authors vouch for the data and analysis and contributed to writing the paper The authors declare no competing interests Nature Communications thanks Christian Nolte and the other anonymous reviewer(s) for their contribution to the peer review of this work Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations Download citation DOI: https://doi.org/10.1038/s41467-023-38313-y Anyone you share the following link with will be able to read this content: a shareable link is not currently available for this article Sign up for the Nature Briefing newsletter — what matters in science By: Kendal Gapinski | Contributing Editor Connect with 100,000+ outpatient OR leaders through print and digital advertising Credit: Insilico Medicine Hong Kong Limited Friday, August 20, 2021 -- Anne-Ulrike Trendelenburg, Ph.D., will present the latest research on the topic Targeting common pathways to treat age-related diseases at the worlds’ largest annual Aging Research and Drug Discovery conference (8th ARDD).  Dr Anne-Ulrike Trendelenburg is the Research Director Novartis Institutes for Biomedical Research Anne-Ulrike Trendelenburg has been working on various pathways (e.g cellular senescence) involved in age-related diseases (e.g sarcopenia) and also premature aging diseases (e.g Trendelenburg has been acting as a management board member of “MouseAge” (COST action BM1402) and led one of the working groups She was author of 3 review papers (Cardoso et al 2018 The conference proceedings of the ARDD are commonly published in peer-reviewed journals with the talks openly available at www.agingpharma.org. Please review the conference proceedings for 2019 and 2020 “Aging is emerging as a druggable condition with multiple pharmaceuticals able to alter the pace of aging in model organisms The ARDD brings together all levels of the field to discuss the most pressing obstacles in our attempt to find efficacious interventions and molecules to target aging The 2021 conference is the best yet with top level speakers from around the globe I’m extremely excited to be able to meet them in person at the University of Copenhagen in late summer.” “Aging research is growing faster than ever on both academia and industry fronts The ARDD meeting unites experts from different fields and backgrounds sharing with us their latest groundbreaking research and developments Our last ARDD meeting took place online and was a great success This year’s event will be a hybrid meeting with virtual and in-person attendees I am particularly excited that being part of the ARDD 2021 meeting will provide an amazing opportunity for young scientists presenting their own work as well as meeting the experts in the field.” said Daniela Bakula “Aging research is gaining traction in the biopharmaceutical industry 6 out of the top 30 pharmaceutical companies in the world prioritized aging research for early-stage discovery or therapeutic pipeline development and several companies employ artificial intelligence for this purpose We organize the annual ARDD conference for eight years in a row and the level of interest in aging biomarkers and noticed exponential growth in registrations over the past two years” Building on the success of the ARDD conferences, the organizers developed the “Longevity Medicine” course series with some of the courses offered free of charge at Longevity.Degree covered in the recent Lanced Healthy Longevity paper titled Longevity medicine: upskilling the physicians of tomorrow About Aging Research for Drug Discovery Conference and drug discovery field will describe the latest progress in the molecular cellular and organismal basis of aging and the search for interventions the meeting will include opinion leaders in AI to discuss the latest advances of this technology in the biopharmaceutical sector and how this can be applied to interventions this year we are expanding with a workshop specifically for physicians where the leading-edge knowledge of clinical interventions for healthy longevity will be described academic and commercial research and foster collaborations that will result in practical solutions to one of humanity's most challenging problems: aging To extend the healthy lifespan of everyone on the planet In the Scheibye-Knudsen lab we use in silico in vitro and in vivo models to understand the cellular and organismal consequences of DNA damage with the aim of developing interventions We have discovered that DNA damage leads to changes in certain metabolites and that replenishment of these molecules may alter the rate of aging in model organisms These findings suggest that normal aging and age-associated diseases may be malleable to similar interventions The hope is to develop interventions that will allow everyone to live healthier About Endurance RP (SEHK:0575.HK) Endurance RP is a diversified investment group based in Hong Kong currently holding various corporate and strategic investments focusing on the healthcare, wellness and life sciences sectors. The Group has a strong track record of investments and has returned approximately US$298 million to shareholders in the 21 years of financial reporting since its initial public offering. https://www.endurancerp.com/ are not responsible for the accuracy of news releases posted to EurekAlert by contributing institutions or for the use of any information through the EurekAlert system Copyright © 2025 by the American Association for the Advancement of Science (AAAS) Thank you for completing the form, here is your download: "+jQuery("body").attr("docName")+" Thank you for completing the form, here is the link to your on-demand webinar: On-Demand Webinar Link once believed to reduce shock symptoms has potential contraindications in EMS EMS relied on the Trendelenburg position – elevating the patient’s feet higher than the head – was a vital treatment for shock and perhaps cause blood to flow from the legs to the trunk German surgeon Friedrich Trendelenburg first described Trendelenburg position in 1873 He would tilt his patients at a 45-degree angle during pelvic surgeries to get a clearer view of their abdominal organs Trendelenburg was also used on the battlefields of World War I when wounded soldiers were tilted in hopes of increasing blood pressure and drawing blood to the heart and brain EMS providers and nurses have held Trendelenburg as the standard shock position for over 100 years but new research shows that it has limited use and might even harm certain patients So EMS providers and educators must ask: Is Trendelenburg position still used And should we still use Trendelenburg position for EMS patients Despite its wide use on early 20th century battlefields there is little evidence that the Trendelenburg position actually helps patients recover from shock A 2012 study published in the Journal of Clinical Anesthesia by Geerts BF found that while Trendelenburg position slightly improved cardiac output Even raising the patient’s legs was more effective at countering hypovolemia A 2012 study published in the American Journal of Critical Care by Margo Halm found the increase in cardiac output and blood pressure was so minimal that the position was “probably not useful in rescue efforts.” Another group of clinicians was even more skeptical of Trendelenburg insisting that patients should “never” be tilted to treat shock except in specific While Trendelenburg position does very little to lessen the effects of shock there are many cases where tilting a patient head-down could cause harm EMS providers in particular must consider the risks of Trendelenburg position and how it can affect patients who have suffered head trauma or spine injuries Repositioning a patient may complicate spinal injuries which is not worth the negligible shift in blood pressure and blood volume Trendelenburg can also increase intracranial pressure, increase cardiac stress and reduce ventilation in vulnerable patients Patients who have suffered rib injuries may find it more difficult to breathe while tilted head-down Trendelenburg position may not be ideal for EMS but it still has applications in hospital and surgical settings surgeons still use Trendelenburg position to gain better access to a patient’s pelvis or lower abdomen Central venous lines are easier to insert when a patient is tilted head-down and the angle offers some relief from certain hernias and cysts Trendelenburg is minimally effective or not at all effective at increasing cardiac output raising blood pressure and treating hypovolemia In prehospital situations involving spinal injury the risks of Trendelenburg position outweigh its minimal benefits Rachel Engel is an award-winning journalist and the senior editor of FireRescue1.com and EMS1.com human stories of first responders and the importance of their work She earned her bachelor’s degree in communications from Cameron University in Lawton and began her career as a freelance writer focusing on government and military issues Engel joined Lexipol in 2015 and has since reported on issues related to public safety Copyright ©2023 Lexipol. All rights reserved.Do Not Sell My Personal Information Home/Patient Care/Emergency Trauma Care Review of:Johnson S, Henderson SO: “Myth: The Trendelenburg position improves circulation in cases of shock.” Canadian Journal Emergency Medicine. 6(1):48-49, 2004. The Science and The StreetFollowing in the footsteps of esteemed Dr. Bryan Bledsoe, the authors of this study undertook the task of exploring the science, or lack thereof, that supports the common practice of placing hypotensive patients in the Trendelenburg position. The Trendelenburg position was originally used to improve surgical exposure of the pelvic organs. It’s credited to German surgeon Friedrich Trendelenburg (1844-1924). After World War I, use of the Trendelenburg position became common practice in managing patients with shock. The position was later used to prevent air embolism during central venous cannulation and to enhance the effects of spinal anesthesia. Some have suggested using a modified Trendelenburg position where the patient is kept flat and the legs are raised above the heart. It has been suggested that this “auto-transfuses” the patient with blood. However, the research doesn’t support this. The volume of blood that drains from the lower extremities in the hypovolemic patient is minimal and does not result in any significant rise in blood pressure. Considering that aspiration is a greater risk with the patient in the Trendelenburg position and the lack of research supporting its use, perhaps it’s time to consider other options. One exciting prospect is an impedance threshold device for spontaneously breathing patients made by the creators of the Res-Q-Pod. Perhaps we can begin to treat our patients based more on science than on 150-year-old ritualized procedures. Why publish in Cureus? Click below to find out. Unlock discounted publishing that highlights your organization and the peer-reviewed research and clinical experiences it produces. Find out how channels are organized and operated, including details on the roles and responsibilities of channel editors. Offering a variety of advertising and sponsorship options for reaching influential specialists from targeted demographic splits. Cureus provides an equitable, efficient publishing and peer reviewing experience without sacrificing publication times. Generate broad awareness and deliver relevant, peer-reviewed clinical experiences directly to potential customers. Dedicated Cranial Radiosurgery: Clinical Experience with New & Innovative SRS Technologies Real-Time Adaptive Motion Management on Helical and Robotic RT Platforms Please note that by doing so you agree to be added to our monthly email newsletter distribution list. This study aimed to demonstrate the reliability of the cardiac cycle efficiency value through its correlation with longitudinal strain by observing the effect of the deep Trendelenburg position. Between May and September 2022, the hemodynamic parameters of 30 patients who underwent robotic assisted laparoscopic prostatectomy under general anesthesia were prospectively evaluated. Although the absence of significant changes in mean arterial pressure and cardiac index after Trendelenburg position suggests that cardiac workload has not changed, changes in cardiac cycle efficiency and longitudinal strain indicate increased cardiac workload due to increased ventriculo-arterial coupling. Intensive Care Medicine and Anesthesiology Volume 10 - 2023 | https://doi.org/10.3389/fmed.2023.1273180 Objective: This study aimed to demonstrate the reliability of the cardiac cycle efficiency value through its correlation with longitudinal strain by observing the effect of the deep Trendelenburg position Participants: Between May and September 2022 the hemodynamic parameters of 30 patients who underwent robotic assisted laparoscopic prostatectomy under general anesthesia were prospectively evaluated Measurements and main results: All invasive cardiac monitoring parameters and longitudinal strain achieved transesophageal echocardiography were recorded in pre-deep Trendelenburg position (T3) and 10th minute of deep Trendelenburg position (T4) Delta values were calculated for the cardiac cycle efficiency and longitudinal strain (values at T4 minus values at T3) The estimated power was calculated as 0.99 in accordance with the cardiac cycle efficiency values at T3 and T4 (effect size: 0.85 standard deviations of the mean difference: 0.22 dP/dt and longitudinal strain were significantly lower than those at T3 (p = 0.009 There was a positive correlation between the delta-cardiac cycle efficiency and delta-longitudinal strain (R2 = 0.36 Conclusion: Although the absence of significant changes in mean arterial pressure and cardiac index after Trendelenburg position suggests that cardiac workload has not changed changes in cardiac cycle efficiency and longitudinal strain indicate increased cardiac workload due to increased ventriculo-arterial coupling Robotic Assisted Laparoscopic Prostatectomy (RALP) is a surgical procedure that provides very good short-term results and is considered the gold standard in prostate cancer surgery because it is minimally invasive (1, 2) The pneumoperitoneum and deep Trendelenburg position (dTD) (at least 25°–45° upside down) required for RALP surgeries can cause significant pathophysiological changes in both the pulmonary and cardiac systems we still have limited data on how cardiac functions change in the dTD we aimed to evaluate the effect of the dTD applied in RALP surgeries on cardiac functions with the CCE and longitudinal strain (LS) [Transesophageal Echocardiography (TEE) parameter] and to show the correlation between CCE and LS After obtaining approval from the Acıbadem Mehmet Ali Aydınlar University Local Ethics Committee (Decision No; 2022-20/05) and signing an informed consent document 30 patients older than 18 years of age who were scheduled for RALP were included in the study a history of myocardial infarction (MI) in the last 3 months and those who did not agree to give their consent were excluded from the study Before the induction of general anesthesia radial artery cannulation was performed in all patients and invasive arterial pressure monitoring was performed with the MostCare(®) (Vytech After induction of anesthesia with 2 mg/kg IV propofol and 1 μg/kg IV remifentanil bolus all patients were given 0.6 mg/kg IV rocuronium for neuromuscular blockade and intubated after mask ventilation the respirotary rate was adjusted such that the tidal volume was 8 ml/kg and the end-expiratory carbon dioxide (EtCO2) was 35 mmHg Positive end-expiratory pressure (PEEP) was set to 5 cmH2O and mechanical ventilation was started in volume-controlled (VCV) mode Anesthesia was maintained by inhalation of an oxygen/air mixture with 40% end-expiratory oxygen percentage (EtO2) and sevoflurane inhalation with a minimum alveolar concentration (MAC) of 0.9–1 The continuity of muscle relaxation was provided with 0.1 mg/kg/h IV rocuronium infusion and the continuity of analgesia was provided with 0.5 μg/kg/min IV remifentanil infusion The depth of anesthesia was monitored using a bispectral index (BIS monitor; Covidien Medical USA) and a range of 40–60 was targeted Analysis for LS included the evaluation of three echocardiographic images from standard mid-esophageal 4-chamber Before anesthesia induction (T1) and after anesthesia induction (T2) after pneumoperitoneum was applied in the supine position (T3) after returning to the supine position (T6) and extubation after (T7) pulse wave analysis parameters and demographic data of the patients were recorded; TEE measurements were performed at T3 and T4 The sample size of the prospective observational study was calculated based on the change of the CCE values before and after dTD it was determined that 30 patients should be included in the study in order for the mean difference of the CCE values at both times to be 0.15 standard deviations: 0.20 and α = 0.05 and power: 0.80 Descriptive parameters are presented as means ± standard deviations Shapiro–Wilcox test was used to test the normal distribution Wilcoxon rank and Freidman tests were used to compare measured parameters before and after dTD position; the Pearson correlation test was used to determine the correlation between CCE and LS Statistical analyses were performed using SPSS version 28.0 A p-value less than 0.05 was accepted for statistical significance The median age of patients included in the study was 64. While 80% of the patients had an ASA score of ≥ 2, 63.3% had a history of hypertension (Table 1) Postoperative troponin levels were within the normal range and no cardiac complications were observed The LS values measured by TEE at the 10th minute (T4) of the patients’ dTD were found to be significantly lower than those before the Trendelenburg position (T3) (p < 0.001) (Table 2) Comparisons of hemodynamic parameters between T3 and T4 At the 10th minute (T4) of the dTD, heart rate, Pulse Pressure Variation (PPV), CCE and dP/dt were significantly decreased compared to T3 (Table 3) Comparison of intraoperative parameters according to time points The CCE values of the patients decreased with the induction of anesthesia (T2) and reached their lowest level at the 10th minute of the Trendelenburg position (T4) (p < 0.001) (Figure 1) after pneumoperitonenum is a administered in the supine position; T4 10th minute after deep trendelenburg position; T5 1st hour after deep trendelenburg position; T6 after returning to the supine position; T7 It has been shown that there is a significant positive correlation between the delta values calculated from the difference of the CCE and LS values measured at the 10th minute before and after Trendelenburg (R2 = 0.36 p < 0.001) (Figure 2) Correlation between delta CCE and delta LS this is the first study to evaluate hemodynamic stability by using CCE in patients undergoing RALP Longitudinal strain indicates the percentage of dimensional deformation that occurs in the heart in the longitudinal axis, is a preload-independent indicator of cardiac contractility and is associated with cardiac efficiency (14, 15). Similar to CCE, LS is an important indicator of VAC (16–18) we aimed to determine the energy consumption and efficiency of the heart in the Trendelenburg position by monitoring these two parameters In physiological conditions if Ea/Ees > 0.5 it is expressed as a situation where cardiac efficiency decreases and energy consumption increases and therefore VAC is impaired < 0.001) and CCE (0.15 ± 0.21 < 0.001) values decreased with the transition from the supine position (T3) to Trendelenburg position (T4) after pneumoperitoneum was applied We found that the blood pressure and Cardiac Index (CI) values did not change These values show us that the heart spends more energy to maintain the same pressure and volume values ESP remained unchanged with Trendelenburg position and therefore Ees and cardiac contractility decreased Despite increased venous return after Trendelenburg position This resulted in the absence of an increase in CI and Mean Arterial Pressure (MAP) consistent with the increase in preload Thus the energy efficiency of the heart is impaired Ruppert et al. (17) investigated the effect of pressure and volume loading on LS and VAC and showed that both volume loading and pressure loading reduced LS and this change was related to VAC it also decreased significantly between T3 and T4 and continued to decrease until the Trendelenburg position ended and returned to the supine position (T6) again These changes show that when factors such as dTD fluid restriction and long surgical time are added more than standard monitoring parameters are required for hemodynamic management in major surgery MAP and Heart Rate (HR) are within normal ranges the cardiac workload may have increased and the heart may have become more inefficient Our study shows that with the transition to the Trendelenburg position the coupling between the ventricle and the arterial system is disrupted we believe that the VAC may be impaired due to increased workload and energy expenditure during Trendelenburg position especially in patients with limited cardiac functions We believe that it is important to know that these changes cannot be monitored with using standard monitoring parameters (HR and SAP) can be used as an indicator of VAC in clinical practice The limitations of this study are that cardiac risky patients were not included and the follow-up period was limited which included the risks related to major surgery These daha show us that double product of heart (HRxSAP) which is also an index of myocardial oxygen consumption Despite double product of heart suggest that cardiac workload does not change changes in CCE and LS indicate that cardiac workload is increased due to impaired VAC Observing of advanced monitoring parameters may be a routine procedure for hemodynamic monitoring in major surgeries using Trendelenburg position and pneumoperitoneum There is a need for both experimental and clinical studies to be conducted in this area with more comprehensive and larger patient numbers The raw data supporting the conclusions of this article will be made available by the authors The studies involving humans were approved by the Acıbadem University and Acıbadem Healthcare Institutions Medical Research Ethics Committee (ATADEK) and robot-assisted radical prostatectomy: a systematic review and cumulative analysis of comparative studies Google Scholar Randomised controlled trial comparing laparoscopic and robot-assisted radical prostatectomy Google Scholar Cardiac function during steep Trendelenburg position and CO2 pneumoperitoneum for robotic-assisted prostatectomy: a trans-oesophageal Doppler probe study Hemodynamic perturbations during robot-assisted laparoscopic radical prostatectomy in 45° Trendelenburg position Pronounced haemodynamic changes during and after robotic-assisted laparoscopic prostatectomy: a prospective observational study Haemodynamic effects of pneumoperitoneum in elderly patients with an increased cardiac risk Google Scholar Ventriculo-arterial coupling: from physiological concept to clinical application in peri-operative care and ICUs Google Scholar Cardiac cycle efficiency: a new parameter able to fully evaluate the dynamic interplay of the cardiovascular system Relationship between N-terminal pro-B-type natriuretic peptide (Nt-proBNP) and cardiac cycle efficiency in cardiac surgery Prognostic value of cardiac cycle efficiency in children undergoing cardiac surgery: a prospective observational study Contemporary trends and risk factors of hemodynamic and myocardial mechanics derived by the pressure recording analytical method after pediatric cardiopulmonary bypass New and clinically relevant echo parameters of regional myocardial function Determinants of left ventricular ejection fraction and a novel method to improve its assessment of myocardial contractility Association of myocardial energetic efficiency with circumferential and longitudinal left ventricular myocardial function in subjects with increased body mass index (the FATCOR Study) Speckle tracking evaluation in endurance athletes: the ‘optimal’ myocardial work Google Scholar Cardiovascular magnetic resonance-derived left ventricular mechanics–strain cardiac power and end-systolic elastance under various inotropic states in swine Longitudinal strain reflects ventriculoarterial coupling rather than mere contractility in rat models of hemodynamic overload–induced heart failure Left ventricular strain and myocardial fibrosis in congenital aortic stenosis Google Scholar Left ventricular-arterial coupling relations in the normal human heart Google Scholar Ventricular efficiency predicted by an analytical model Google Scholar Optimal arterial resistance for the maximal stroke work studied in isolated canine left ventricle The role of ventricular–arterial coupling in cardiac disease and heart failure: assessment clinical implications and therapeutic interventions A consensus document of the European Society of Cardiology Working Group on Aorta & Peripheral Vascular Diseases European Association of Cardiovascular Imaging Assessment of myocardial oxygen consumption (Vo2) and systolic pressure-volume area (PVA) in human hearts Google Scholar Google Scholar Redefining cardiovascular performance during resuscitation: ventricular stroke work Assessment of left ventricular function by pulse wave analysis in critically ill patients Google Scholar Ventricular-vascular interaction in heart failure Google Scholar Performance comparison of ventricular and arterial dP/dtmax for assessing left ventricular systolic function during different experimental loading and contractile conditions Google Scholar Baroreceptor modulation of the cardiovascular system Regional strain and strain rate measurements by cardiac ultrasound: principles Eur J Echocardiogr J Work Group Echocardiogr Eur Soc Cardiol Association between myocardial extracellular volume and strain analysis through cardiovascular magnetic resonance with histological myocardial fibrosis in patients awaiting heart transplantation Hypertension and ventricular–arterial uncoupling in collegiate American football athletes J Am Heart Assoc Cardiovasc Cerebrovasc Dis Left ventricular performance during propofol or methohexital anesthesia: isotopic and invasive cardiac monitoring Haemodynamics and cardiac function during robotic-assisted laparoscopic prostatectomy in steep Trendelenburg position Google Scholar Changes in intrathoracic blood volume associated with pneumoperitoneum and positioning Google Scholar Effects of posture and prolonged pneumoperitoneum on hemodynamic parameters during laparoscopy Google Scholar Changes in cardiac function and hemodynamics during robot-assisted laparoscopic prostatectomy with steep head-down tilt: a prospective observational study Güçyetmez B and Toraman F (2023) The evaluation of cardiac functions in deep Trendelenburg position during robotic-assisted laparoscopic prostatectomy Copyright © 2023 Kılınç, Yildirim, Ulugöl, Büyüköner, Güçyetmez and Toraman. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) *Correspondence: Emir Kılınç, ZHJlbWlya2lsaW5jQGdtYWlsLmNvbQ== Metrics details Fluid administration is widely used to treat hypotension in patients undergoing veno-venous extracorporeal membrane oxygenation (VV-ECMO) excessive fluid administration may lead to fluid overload can aggravate acute respiratory distress syndrome (ARDS) and increase patient mortality predicting fluid responsiveness is of great significance for VV-ECMO patients This prospective single-center study was conducted in a medical intensive care unit (ICU) and finally included 51 VV-ECMO patients with ARDS in the prone position (PP) baseline carotid corrected flow time (FTcBaseline) and respirophasic variation in carotid artery blood flow peak velocity (ΔVpeakCA) were taken before and after the Trendelenburg position or volume expansion Fluid responsiveness was defined as a 15% or more increase in stroke volume index as assessed by transthoracic echocardiography after the volume expansion (VE) 33 patients (64.7%) were identified as fluid responders Stroke volume index variation induced by the Trendelenburg position (ΔSVITrend) and ΔVpeakCA demonstrated superior predictive performance of fluid responsiveness 0.80–0.98) with an optimal threshold of 14.5% (95% CI with the sensitivity and specificity were 82% (95% CI 0.76–0.98) with an optimal threshold of 332ms (95% CI the sensitivity and specificity were 85% (95% CI FTcBaseline and ΔVpeakCA could effectively predict fluid responsiveness in VV-ECMO patients with ARDS in the PP FTcBaseline is easier and more direct to acquire and it does not require Trendelenburg position or VE making it a more accessible and efficient option for assessing fluid responsiveness It through elevating the legs to simulate fluid expansion primarily relying on the increased venous return when the patient is in the supine position patients receiving VV-ECMO support for ARDS are often placed in the prone position (PP) to improve ventilation leg elevation is restricted by the body’s position passive leg raising is not applicable for assessing fluid responsiveness in patients in PP the specificity and complexity of VV-ECMO patients in PP limits the applicability of traditional methods for assessing fluid responsiveness The measurements of these parameters offer advantages such as rapidity it is worth noting that there are currently few studies in patients on VV-ECMO with ARDS in PP The efficacy of these parameters in assessing fluid responsiveness in these patients remains not enough clear at present The primary aim of this study was to evaluate the value of stroke volume index variation induced by the Trendelenburg position (ΔSVITrend) and ΔVpeakCA to predict fluid responsiveness in patients on VV-ECMO with ARDS in the PP Secondary objectives were to evaluate the diagnostic performance of PPV and SVV to predict fluid responsiveness in these patients single-center study was conducted in the intensive care unit (ICU) between May 2022 and February 2024 It was approved by the Institutional Review Board of Quzhou People’s Hospital (Quzhou China: Number B 2022-083) and performed in accordance with the Declaration of Helsinki All research was performed in accordance with relevant guidelines/regulations Informed consent was obtained from all participants and/or their legal guardians VV-ECMO patients admitted to intensive care unit (ICU) were recruited in this study The Inclusion criteria including: (1) adults (≥ 18 years) diagnosed with ARDS; (2) received prone ventilation therapy during VV-ECMO; (3) monitoring with the pulse indicator continuous cardiac output (PiCCO)® device (Pulsion Medical Systems Germany); (4) patients who presented with at least one clinical sign of inadequate tissue perfusion for less than 24 h in the absence of a contraindication for fluids: Hypotension (systolic blood pressure < 90 mmHg or mean arterial pressure (MAP) < 65 mmHg) organ hypoperfusion (evidenced by mottled skin or delayed capillary refill) Exclusion criteria were patients with contraindications for volume expansion (VE) (severe cardiac dysfunction a poor ultrasonographic window for carotid doppler measurements any contraindications to Trendelenburg position (head injury or intracranial hypertension Baseline-2: recover to the same position as baseline-1; VE test: administration of 500 ml crystalloids over 15 min without postural change. After each step is completed and stabilized for 1 min, record the hemodynamic parameters. For enhanced accuracy of the acquired data, measurements were taken three times for each patient, and the average was calculated to determine the final parameters. (a) An outline of each step; (b) a clinical scenery of VV-ECMO patient in the prone position; (c) the 15° upward bed angulation for measurements at baselines and volume expansion test; (d) The 15° downward bed angulation for measurements in the Trendelenburg position The PiCCO® catheter was inserted into the patient’s femoral artery Using the GE B850 monitor equipped with a PiCCO® module (GE Healthcare the following hemodynamic parameters were monitored: PPV where FT represents the cycle time from the onset of systole to the dual rotation trace and heart rate (HR) is obtained by measuring the heartbeat interval at the onset of Doppler blood flow We documented all data related to these parameters Follow-up was conducted for all study patients until discharge or death recording clinical outcomes such as the duration of MV A value of P < 0.05 (two-tailed test) was considered statistically significant Fluid responsiveness was observed in 33 of the 51 measurements (64.7%). The hemodynamic variables are shown in are shown (Table 2) The SVI and FTc increase between responders and non-responders after Trendelenburg position or VE whereas an increasing trend was more apparent in responders Trendelenburg position or VE significantly decreased the PPV The relationship between ΔSVIVE and the five parameters.The grey line is the regression line. The gray dotted line area is the 95% confidence interval of the regression line. (a) ΔSVITrend, Stroke volume index variation induced by the Trendelenburg position; (b) FTcBaseline, baseline carotid artery corrected flow time; (c) ΔVpeakCA, respirophasic variation in carotid artery blood flow peak velocity; (d) PPV, pulse pressure variation; (e) SVV, stroke volume variation. Receiver operating characteristics curves from five diagnostics tests to detect fluid responsiveness. (a) ΔSVITrend, Stroke volume index variation induced by the Trendelenburg position; (b) FTcBaseline, baseline carotid artery corrected flow time; (c) ΔVpeakCA, respirophasic variation in carotid artery blood flow peak velocity; (d) PPV, pulse pressure variation; (e) SVV, stroke volume variation. Stroke volume index variation induced by the Trendelenburg position; (b) FTcBaseline baseline carotid artery corrected flow time; (c) ΔVpeakCA respirophasic variation in carotid artery blood flow peak velocity; (d) PPV 0.76–0.98) with an optimal threshold of 332ms PPV and SVV displayed lower predictive performance The AUC were 0.75 (95% CI 0.61–0.89) and 0.76 (95% CI 0.61–0.90) The gray zone of optimal thresholds was 7.5% (95% CI 6.5–9.5%) and 11.5% (95%CI 10.5–14.5%) and included more patients in grey zone (39% and 41%) Our study evaluates the diagnostic value of several parameters to predict fluid responsiveness in Patients on VV-ECMO with ARDS in the PP under protective ventilation (VT 4–6 ml/kg−1 PBW) The main findings are that: (1) ΔSVITrend is a highly reliable parameter to predict fluid responsiveness with sensitivity of 82% (95% CI 66–91%) and specificity of 83% (95% CI 61–94%); (2) FTcBaseline also is a highly reliable parameter to predict fluid responsiveness which had an AUC is 0.87 (95% CI 0.76–0.98) with a higher sensitivity of 85% (95% CI 69–93%) than ΔSVITrend and specificity of 83% (95% CI 61–94%) (3) While ΔVpeakCA also had acceptable predictive performance for fluid responsiveness and specificity [78% (95% CI 55–91%)] are all inferior to those of ΔSVITrend and FTcBaseline (4) PPV and SVV is moderate sensitivity to predict fluid responsiveness This study enables clinicians to predict fluid responsiveness in such patients non-invasively facilitating the development of appropriate fluid management strategies fluid management in VV-ECMO patients is closely intertwined with their condition Accurate prediction of fluid responsiveness is crucial to improve prognosis for these patients The evaluation of fluid responsiveness has always been a hot and challenging area of research ranging from static parameters such as CVP and IVC to dynamic parameters such as SVV and PPV Evaluation indicators have undergone a transition from static to dynamic and from invasive to non-invasive The purpose of our study of volume responsiveness was to improve organ tissue ischemia and hypoxia while avoiding volume overload increasing mortality and hospitalization time PPV and SVV may not applicable for predicting fluid responsiveness in such patients it is still important to consider that leg elevation may pose risks of catheter displacement or deformation the Trendelenburg position may be more suitable for assessing fluid responsiveness in our study population all patients underwent Trendelenburg position in the PP without any adverse impact on the ECMO system The Trendelenburg position induced a 64.7% change in SVI indicating a similar physiological effect to passive leg raising The high correlation between ΔSVITrend and ΔSVIVE suggests that the Trendelenburg position can be used to assess fluid responsiveness in patients undergoing VV-ECMO in the PP Our study provides robust evidence supporting ΔSVITrend FTcBaseline and ΔVpeakCA are able to predict fluid responsiveness in patients on VV-ECMO with ARDS in the PP while neither PPV and SVV reached acceptable predictive performance to predict fluid responsiveness FTcBaseline can be directly obtained using neck ultrasound eliminating the need Trendelenburg position or VE This characteristic enhances its practicality in clinical settings they required low tidal volume ventilation (4–6 ml/kg) as part of lung-protective strategies; thus our findings may not extend to patients receiving higher tidal volumes (6–8 ml/kg or > 8 ml/kg) we did not conduct comparisons with findings from non-prone positions which may limit the generalizability of our results to other positional settings this study did not include other tests for fluid responsiveness such as the Mini Fluid Challenge or the End-Expiratory Occlusion test we aim to further explore these aspects to enhance fluid responsiveness assessment The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request Combes, A. et al. Extracorporeal membrane oxygenation for severe acute respiratory distress syndrome. N. Engl. J. Med. 378, 1965–1975. https://doi.org/10.1056/NEJMoa1800385 (2018) Bellani, G. et al. Epidemiology, patterns of care, and mortality for patients with acute respiratory distress syndrome in intensive care units in 50 countries. JAMA 315, 788. https://doi.org/10.1001/jama.2016.0291 (2016) Sud, S. et al. Prone ventilation reduces mortality in patients with acute respiratory failure and severe hypoxemia: Systematic review and meta-analysis. Intensive Care Med. 36, 585–599. https://doi.org/10.1007/s00134-009-1748-1 (2010) Balk, R. A. Positive end-expiratory pressure setting in adults with acute lung injury and acute respiratory distress syndrome: A randomized controlled trial. Yearbook Crit. Care Med. 2009, 6–8. https://doi.org/10.1016/S0734-3299(08)79045-2 (2009) Schmid, C. et al. Venovenous extracorporeal membrane oxygenation for acute lung failure in adults. J. Heart Lung Transplantation. 31, 9–15. https://doi.org/10.1016/j.healun.2011.07.013 (2012) Tonna, J. E. et al. Management of adult patients supported with venovenous extracorporeal membrane oxygenation (VV ECMO): Guideline from the extracorporeal life support organization (ELSO). ASAIO J. 67, 601–610. https://doi.org/10.1097/MAT.0000000000001432 (2021) Kim, H. et al. Permissive fluid volume in adult patients undergoing extracorporeal membrane oxygenation treatment. Crit. Care. 22, 270. https://doi.org/10.1186/s13054-018-2211-x (2018) Messmer, A. S. et al. Fluid overload and mortality in adult critical care patients—A systematic review and meta-analysis of observational studies*. Crit. Care Med. 48, 1862–1870. https://doi.org/10.1097/CCM.0000000000004617 (2020) Schmidt, M. et al. Impact of fluid balance on outcome of adult patients treated with extracorporeal membrane oxygenation. Intensive Care Med. 40, 1256–1266. https://doi.org/10.1007/s00134-014-3360-2 (2014) Douglas, I. S. et al. Fluid Response Evaluation in Sepsis Hypotension and Shock. Chest 158, 1431–1445. https://doi.org/10.1016/j.chest.2020.04.025 (2020) Monnet, X., Marik, P. E. & Teboul, J-L. Prediction of fluid responsiveness: An update. Ann. Intensive Care. 6, 111. https://doi.org/10.1186/s13613-016-0216-7 (2016) Jozwiak, M., Monnet, X. & Teboul, J-L. Prediction of fluid responsiveness in ventilated patients. Ann. Transl Med. 6, 352–352. https://doi.org/10.21037/atm.2018.05.03 (2018) Monnet, X. & Teboul, J-L. Assessment of fluid responsiveness: Recent advances. Curr. Opin. Crit. Care. 24, 190–195. https://doi.org/10.1097/MCC.0000000000000501 (2018) Huang, H. et al. Value of variation index of inferior vena cava diameter in predicting fluid responsiveness in patients with circulatory shock receiving mechanical ventilation: A systematic review and meta-analysis. Crit. Care. 22, 204. https://doi.org/10.1186/s13054-018-2063-4 (2018) Marik, P. E. & Cavallazzi, R. Does the central venous pressure predict fluid responsiveness? An updated meta-analysis and a plea for some common sense*. Crit. Care Med. 41, 1774–1781. https://doi.org/10.1097/CCM.0b013e31828a25fd (2013) Yang, X. & Du, B. Does pulse pressure variation predict fluid responsiveness in critically ill patients? A systematic review and meta-analysis. Crit. Care. 18, 650. https://doi.org/10.1186/s13054-014-0650-6 (2014) Backer, D. D. & Vincent, J-L. Infuence of respiratory rate on stroke volume variation in mechanically ventilated patients. J. Am. Soc. Anesthesiol. 110(5), 1092–1097. https://doi.org/10.1097/ALN.0b013e31819db2a1 (2009) Michard, F., Chemla, D. & Teboul, J-L. Applicability of pulse pressure variation: How many shades of grey? Crit. Care 19, 144. https://doi.org/10.1186/s13054-015-0869-x (2015) Guinot, P-G. et al. Passive leg raising can predict fluid responsiveness in patients placed on venovenous extracorporeal membrane oxygenation. Crit. Care. 15, R216. https://doi.org/10.1186/cc10451 (2011) Geerts, B. F. et al. Comprehensive review: Is it better to use the Trendelenburg position or passive leg raising for the initial treatment of hypovolemia? J. Clin. Anesth. 24, 668–674. https://doi.org/10.1016/j.jclinane.2012.06.003 (2012) Monnet, X., Shi, R. & Teboul, J-L. Prediction of fluid responsiveness. What’s new? Ann. Intensive Care. 12, 46. https://doi.org/10.1186/s13613-022-01022-8 (2022) Wang, H. et al. Value of corrected flow time in common carotid artery in predicting volume responsiveness under mechanical ventilation. Shock 58, 28–33. https://doi.org/10.1097/SHK.0000000000001959 (2022) Song, Y. et al. Respirophasic carotid artery peak velocity variation as a predictor of fluid responsiveness in mechanically ventilated patients with coronary artery disease. Br. J. Anaesth. 113, 61–66. https://doi.org/10.1093/bja/aeu057 (2014) Pace, R. et al. Carotid vs. aortic velocity time integral and peak velocity to predict fluid responsiveness in mechanically ventilated patients. A comparative study. Minerva Anestesiol. 88, 352–360. https://doi.org/10.23736/S0375-9393.21.16035-3 (2022) Ramsay, M. A. E. et al. Controlled Sedation with Alphaxalone-Alphadolone. BMJ 2, 656–659. https://doi.org/10.1136/bmj.2.5920.656 (1974) Nassar, B. et al. Trendelenburg position does not increase cross-sectional area of the internal jugular vein predictably. Chest 144, 177–182. https://doi.org/10.1378/chest.11-2462 (2013) Ugalde, D. et al. Transthoracic cardiac ultrasound in prone position: A technique variation description. Intensive Care Med. 44, 986–987. https://doi.org/10.1007/s00134-018-5049-4 (2018) Peachey, T. et al. The assessment of circulating volume using inferior vena cava collapse index and carotid Doppler velocity time integral in healthy volunteers: A pilot study. Scand. J. Trauma. Resusc. Emerg. Med. 24, 108. https://doi.org/10.1186/s13049-016-0298-0 (2016) Mohammadinejad, P. & Hossein-Nejad, H. Calculation of corrected flow time: Wodey’s formula vs. Bazett’s formula. J. Crit. Care. 44, 154–155. https://doi.org/10.1016/j.jcrc.2017.10.046 (2018) Michard, F. et al. Global end-diastolic volume as an indicator of cardiac preload in patients with septic shock*. Chest 124, 1900–1908. https://doi.org/10.1378/chest.124.5.1900 (2003) Kim, D-H. et al. Carotid ultrasound measurements for assessing fluid responsiveness in spontaneously breathing patients: Corrected flow time and respirophasic variation in blood flow peak velocity. Br. J. Anaesth. 121, 541–549. https://doi.org/10.1016/j.bja.2017.12.047 (2018) Coste, J. & Pouchot, J. A grey zone for quantitative diagnostic and screening tests. Int. J. Epidemiol. 32, 304–313. https://doi.org/10.1093/ije/dyg054 (2003) Combes, A. et al. What is the niche for extracorporeal membrane oxygenation in severe acute respiratory distress syndrome? Curr. Opin. Crit. Care. 18, 527–532. https://doi.org/10.1097/MCC.0b013e328357f090 (2012) Hutchens, M., Song, H. & Ibsen, L. Extracorporeal membrane oxygenation for ARDS in adults. N. Engl. J. Med. 366(6), 575–576. https://doi.org/10.1056/NEJMc1114604 (2012) Thompson, B. T., Chambers, R. C. & Liu, K. D. Acute respiratory distress syndrome. N. Engl. J. Med. 377, 562–572. https://doi.org/10.1056/NEJMra1608077 (2017) Hamzaoui, O. & Teboul, J-L. Central venous pressure (CVP). Intensive Care Med. 48, 1498–1500. https://doi.org/10.1007/s00134-022-06835-6 (2022) Teboul, J-L. et al. Arterial pulse pressure variation with mechanical ventilation. Am. J. Respir Crit. Care Med. 199, 22–31. https://doi.org/10.1164/rccm.201801-0088CI (2019) Reuter, D. A. et al. Stroke volume variations for assessment of cardiac responsiveness to volume loading in mechanically ventilated patients after cardiac surgery. Intensive Care Med. 28, 392–398. https://doi.org/10.1007/s00134-002-1211-z (2002) Prone position affects stroke volume variation performance in predicting fluid responsiveness in neurosurgical patients (2015) Slutsky, A. S. & Ranieri, V. M. Ventilator-induced lung injury. N. Engl. J. Med. 369, 2126–2136. https://doi.org/10.1056/NEJMra1208707 (2013) Guérin, C. et al. Prone positioning in severe acute respiratory distress syndrome. N. Engl. J. Med. 368, 2159–2168. https://doi.org/10.1056/NEJMoa1214103 (2013) Zaaqoq, A. M. et al. Beneficial effect of prone positioning during venovenous extracorporeal membrane oxygenation for coronavirus disease 2019*. Crit. Care Med. 50, 275–285. https://doi.org/10.1097/CCM.0000000000005296 (2022) Petit, M. et al. Prone-positioning for severe acute respiratory distress syndrome requiring extracorporeal membrane oxygenation. Crit. Care Med. 50, 264–274. https://doi.org/10.1097/CCM.0000000000005145 (2022) Giani, M. et al. Timing of prone positioning during venovenous extracorporeal membrane oxygenation for acute respiratory distress syndrome. Crit. Care Med. 51, 25–35. https://doi.org/10.1097/CCM.0000000000005705 (2023) Giani, M. et al. Prone positioning during venovenous extracorporeal membrane oxygenation for acute respiratory distress syndrome: A pooled individual patient data analysis. Crit. Care. 26, 8. https://doi.org/10.1186/s13054-021-03879-w (2022) Pelosi, P. et al. Effects of the prone position on respiratory mechanics and gas exchange during acute lung injury. Am. J. Respir Crit. Care Med. 157, 387–393. https://doi.org/10.1164/ajrccm.157.2.97-04023 (1998) Jung, S. et al. Ability of carotid corrected flow time to predict fluid responsiveness in patients mechanically ventilated using low tidal volume after surgery. JCM 10, 2676. https://doi.org/10.3390/jcm10122676 (2021) Luo, J. et al. Trendelenburg maneuver predicts fluid responsiveness in patients on veno-arterial extracorporeal membrane oxygenation. Ann. Intensive Care. 11, 16. https://doi.org/10.1186/s13613-021-00811-x (2021) Hung, K-C. et al. Diagnostic efficacy of carotid ultrasound for predicting the risk of perioperative hypotension or fluid responsiveness: A meta-analysis. Diagnostics 13, 2290. https://doi.org/10.3390/diagnostics13132290 (2023) Monnet, X., Marik, P. & Teboul, J-L. Passive leg raising for predicting fluid responsiveness: A systematic review and meta-analysis. Intensive Care Med. 42, 1935–1947. https://doi.org/10.1007/s00134-015-4134-1 (2016) Rezoagli, E. et al. Physical manoeuvres in patients with ARDS and low compliance: Bedside approaches to detect lung hyperinflation and optimise mechanical ventilation. Eur. Respir J. 61, 2202169. https://doi.org/10.1183/13993003.02169-2022 (2023) Download references The authors wish to thank all research staff and patients for participating in this study This work was supported in part by grants from the Project of Zhejiang Provincial Department of Health (No 2023KY1296) and Quzhou Bureau of Science and Technology (No Quzhou Hospital of Traditional Chinese Medicine The Quzhou Affiliated Hospital of Wenzhou Medical University All authors read and reviewed the manuscript single-center study was conducted in the ICU between May 2022 and February 2024 Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations Below is the link to the electronic supplementary material Download citation DOI: https://doi.org/10.1038/s41598-024-83038-7 Sorry, a shareable link is not currently available for this article. Sign up for the Nature Briefing newsletter — what matters in science, free to your inbox daily. When adjusting or re-positioning one side of the patient, be sure to check the opposite side for potential problems. Another key point to tucking is to make sure the arm is not pinned underneath the body. Wrap the sheet around the arm and then push the sheet underneath the patient's body to provide resistance so the arm doesn't fall off the bed. "That sheet is holding the arm on the bed," says Dr. Brueseke, "so if you just tuck, tuck, tuck, you can accidentally tuck the arm under the body." The patient is upside down, but all the weight, pressure, tension and heaviness are on the thing that's built to hold that kind of weight. "It's remarkably effective. It's pretty impressive how you can put that little speed bump right there underneath the neck and you put the patient in steep Trendelenburg and she sits right on that spot," says Dr. Brueseke. You can also keep Trendelenburg patients stable and pressure-ulcer free with a combination of speed bumps and a pad that molds and conforms to the patient's contour to prevent unwanted patient sliding. A strap across the chest adds extra stability. 5. Chest strap or not? Some surgeons like to use a chest strap to help secure the patient to the table while in Trendelenburg. But this can create a ventilation problem for larger patients. "Not only are you pushing their abdomen contents toward their lungs by tilting them on their head," says Mr. Klev, "but now you're strapping their chest to the bed and potentially creating more problems." Adds Dr. Mini: "The restriction on ventilating the patient when the chest straps were in place bothered anesthesia, especially in our larger patients. This was why other methods of supporting the patient on the operative tables arose." Connect with 100,000+ outpatient OR leaders through print and digital advertising, custom programs, e-newsletters, event sponsorship, and more! The analgesia nociception index (ANI) monitor is a nociception monitoring device based on heart rate variability. We aimed to determine the effect of ANI monitor-based intraoperative nociception control on the perioperative stress response during laparoscopic surgery in the Trendelenburg position. ANI monitor-based nociception control in laparoscopic surgery in the Trendelenburg position did not improve perioperative stress responses, intraoperative opioid consumption, or postoperative clinical outcomes. Clinical trial registration:ClinicalTrials.gov (NCT04343638). Volume 10 - 2023 | https://doi.org/10.3389/fmed.2023.1196153 Introduction: The analgesia nociception index (ANI) monitor is a nociception monitoring device based on heart rate variability We aimed to determine the effect of ANI monitor-based intraoperative nociception control on the perioperative stress response during laparoscopic surgery in the Trendelenburg position 72 female patients who underwent total laparoscopic hysterectomy were randomized to either the control or ANI group Intraoperative nociception was controlled by remifentanil administration in a conventional manner (based on blood pressure and heart rate) in the control group and by ANI monitoring in the ANI group Perioperative stress responses were estimated by measuring the levels of serum catecholamines and catabolic stress hormones at three timepoints: after loss of consciousness Results: The serum cortisol level at the end of surgery was significantly higher in the ANI group than in the control group (p < 0.001) although more remifentanil was administered in the ANI group than in the control group (p < 0.001) Changes in the other estimators’ levels were comparable between groups during the perioperative period The hemodynamic profiles during surgery were also significantly different between the two groups Phenylephrine use to treat hypotension was more common in the ANI group than in the control group (p = 0.005) postoperative clinical outcomes such as pain and nausea/vomiting did not differ between groups Conclusion: ANI monitor-based nociception control in laparoscopic surgery in the Trendelenburg position did not improve perioperative stress responses Clinical trial registration: ClinicalTrials.gov (NCT04343638) Adequate pain control is important for enhanced recovery after surgery. Although laparoscopy has improved postoperative clinical outcomes (1, 2), such as early mobilization and hospital discharge in gynecologic abdominal surgeries, patients undergoing total laparoscopic hysterectomy have been reported to experience severe pain after surgery (3) Pain in conscious patients is assessed based on the patient’s self-reported pain scores such as numerical rating scale (NRS); however, the pain scores cannot be used to monitor nociception in unconscious patients. Conventionally, anesthesiologists control nociception according to indirect indicators of pain such as patient movement, high blood pressure, and tachycardia during surgery (4) these are not objective indicators of nociception and nociception cannot be excluded even in the absence of these clinical symptoms pneumoperitoneum and the steep Trendelenburg position in laparoscopic hysterectomy may disturb ANI monitoring because they can affect autonomic nervous system activity we investigated whether ANI monitor-based nociception control can reduce the perioperative stress response compared with conventional nociception control by comparing serum catecholamines and inflammatory cytokines in patients undergoing total laparoscopic hysterectomy The Institutional Review Board of Yonsei University Health System, Seoul, South Korea, approved this trial (#4–2020-0130) on April 1, 2020. This study was registered before patient enrolment at ClinicalTrial.gov (NCT04343638 2020) and conducted between May 2020 and October 2021 All participants provided written informed consent Female patients aged 20–65 years who underwent elective total laparoscopic hysterectomy for uterine myoma or adenomyosis were recruited We excluded patients with ASA physical status class ≥IV anteroposterior diameter of uterus >12 cm diseases affecting the autoimmune system (such as immune disease or diabetic neuropathy) use of medications affecting ANI monitoring (antimuscarinics A computer-generated random code generator was used to randomly allocate participants to either the control group (conventional nociception control group) or ANI group (ANI monitor-guided nociception control group) in a 1:1 ratio The patients and investigators in charge of data collection and outcome analyses were blinded but the anesthesia providers were not blinded to randomization ANI monitoring was also applied to all participants While nociception control was performed based on ANI monitoring in the ANI group the ANI monitor was covered with black paper so that it could not be observed in the control group 2 mg/kg of propofol was administered and remifentanil was infused using an effect-site target-controlled infusion pump with an initial target effect-site concentration of 3 ng/mL according to the Minto model After confirmation of loss of consciousness 0.6 mg/kg of rocuronium was administered the patients were mechanically ventilated with 6–8 mL/kg predicted body weight of tidal volume and respiratory rates were adjusted to maintain the end-tidal CO2 between 35 and 40 mmHg Anesthetic depth was maintained with sevoflurane to adjust the BIS value between 40 and 60 in all patients throughout the surgery According to the attending anesthesiologist’s decision an additional 10 mg of rocuronium was administered to maintain a train-of-four count of less than 2 throughout the surgery In the control group, the remifentanil concentration was adjusted to 0.5 or 1.0, according to the judgment of the attending anesthesiologist based on mean arterial pressure (MAP) and heart rate. In the ANI group, when the ANIm values deviated from the target value of 50–70 (7) the concentration of remifentanil was adjusted by 0.5 or 1.0 Remifentanil concentration lower than 1.5 ng/mL was not allowed in either group Total laparoscopic hysterectomies were performed with two ports in the 30° Trendelenburg position by four expert gynecologists Pneumoperitoneum was maintained with an intra-abdominal pressure of 12 mmHg and a CO2 flow rate of 20 L/min during the surgery The specimens were extracted transvaginally in specimen bag All patients received 8 mg ondansetron 30 min before the end of surgery 1 g acetaminophen was administered to patients weighing >50 kg and 15 mg/kg acetaminophen was administered to patients weighing <50 kg 30 min before the end of surgery Phenylephrine was used to correct isolated hypotension (MAP <60 mmHg) without bradycardia Combined hypotension and bradycardia (<45 bpm) was managed with ephedrine Glycopyrrolate was administered to treat the isolated bradycardia In the case of bradycardia refractory to glycopyrrolate On arrival at the post-anesthetic care unit (PACU) Oxycodone (0.05 mg/kg) was used when the NRS score for pain was higher than 4 and 10 mg metoclopramide was infused when the NRS score for nausea was higher than 4 Patients were discharged from the PACU after an NRS for pain lower than 4 was reported ANI data recorded at 1-s intervals were downloaded after discontinuation of the main anesthetic at the end of surgery The mean ANIm values from the start of induction of general anesthesia to cessation of an anesthetics percentage of time with adequate analgesia with an ANIm value of 50–70 and percentage of time with inadequate analgesia with an ANIm value <50 were assessed for each patient The primary outcomes in the present study were perioperative levels of catecholamines Blood sampling was performed at three timepoints: after loss of consciousness A peripheral venous catheter for blood sampling was inserted immediately after loss of consciousness and maintained until the final sampling Blood samples were centrifuged and stored at −80°C until analysis Quantification of serum catecholamines (norepinephrine and high mobility group box 1) was performed using enzyme-linked immunosorbent assay kits Secondary outcomes included intraoperative MAP and heart rate total dose of remifentanil and phenylephrine usage NRS for pain at the PACU at five timepoints (at admission and 10 NRS score for nausea at PACU admission and 30 min after PACU admission usage of oxycodone and metoclopramide in the PACU Previously, the mean (standard deviation) of serum norepinephrine levels in patients undergoing laparoscopic gynecologic surgery at the end of surgery was reported to be 750 (320) pg./mL (22) Assuming that a 30% reduction in norepinephrine level is clinically meaningful 72 patients were required to provide 80% power at a significance level of 0.05 Descriptive data are presented as the mean (standard deviation) or median (interquartile range) Student’s t-test or Mann–Whitney U-test was used for continuous variables and the chi-squared test or Fisher’s exact test was used for categorical variables We performed repeated analyses of variance with group and the interaction between group and time for repeated variables (catecholamine and stress hormone levels All statistical analyses were performed using SPSS Statistics for Windows version 23 (IBM A total of 72 patients deemed eligible for this study were randomly allocated to either the control group or the ANI group (Figure 1). The baseline patient demographics are presented in Table 1. Table 2 shows the ANI values and remifentanil administration data There was no significant difference in the mean ANIm values during anesthesia and surgery The percentage of time spent with adequate ANIm values between 50 and 70 was higher in the ANI group than in the control group (48.9 [9.2] % vs the percentage of time spent with adequate ANIm values did not differ between the two groups Remifentanil consumption was significantly higher in the ANI group than in the control group Figure 2 depicts the changes in biochemical markers reflecting the stress response during surgery or perioperative inflammation and tissue damage. Although the changes in cortisol levels in the perioperative period were not significantly different between the two groups (Figure 2C pgroup × time = 0.062) the cortisol level at the end of surgery (T2) was significantly higher in the ANI group than in the control group in the post-hoc analysis (p < 0.001) The changes in other markers were comparable between the two groups Perioperative changes in serum (A) norepinephrine and (G) high mobility group box 1 of the control and ANI group at three timepoints Intraoperative changes of mean arterial pressure (A) and heart rate (B) between the control and ANI group 10 min after the start of surgery; T3 30 min after the start of surgery; T4 *p < 0.05; **p < 0.01 Pain scores during PACU stay did not differ between the two groups (pgroup × time = 0.255; Supplementary Figure 1). As shown in Table 3 oxycodone use did not differ between groups Other parameters related to nausea and vomiting did not significantly differ between groups ANI monitoring has been approved and adopted in clinical practice in many countries; however the effect of ANI monitor-based nociception control during surgery on clinical outcomes has not been fully determined The current study demonstrated that the application of ANI in laparoscopic hysterectomy did not reduce perioperative catecholamine levels when compared with conventional nociception control using hemodynamic variables the serum cortisol level at the end of surgery was higher in the ANI group than in the control group despite the higher dose of intraoperative remifentanil used the conventional application of ANI monitoring cannot improve the perioperative stress response in laparoscopic hysterectomy including postoperative pain and nausea/vomiting CO2 pneumoperitoneum and steep (30°) Trendelenburg position during surgery in our study can affect ANI values in addition to surgical nociception we had more trouble maintaining adequate ANI values after the induction of pneumoperitoneum and Trendelenburg positioning than before surgery Considering that the total duration of adequate ANIm values during surgery was not significantly different between groups despite the higher remifentanil administration in the ANI group decreased parasympathetic activity (or increased sympathetic activity) by pneumoperitoneum may not be controlled well by opioid administration or may not be reflected by the ANI monitor Increased stress responses due to hypotension may mask the reduced stress responses following opioid administration The association between the autonomic nervous system and the immune system has been revealed. The vagus nerve, one of the main nerves of the parasympathetic nervous system, monitors and regulates peripheral inflammation (38) we hypothesized that maintaining parasympathetic dominance during surgery by ANI monitoring could affect intra- and postoperative inflammatory responses which may result in differences in tissue damage and inflammatory response during surgery between the two groups there were no differences in inflammatory cytokines or markers of tissue damage (high mobility group box 1) between groups postoperative pain outcomes were not different between the two groups there was no difference between the two groups in the perioperative stress response or inflammatory response which is consistent with the postoperative pain outcomes the investigator in charge of anesthesia was not blinded to the randomization the investigator in charge of laboratory measurements and postoperative outcome assessments was blinded to group allocation this study was conducted based on special clinical settings such as laparoscopy in the steep Trendelenburg position in relatively young female patients and the results of this study cannot be generalized to other patient populations anticholinergic and ephedrine were used to treat bradycardia and hypotension this medication can represent a clinical picture in this surgical setting the present study showed that nociception control with ANI monitoring according to the manufacturer’s recommendations did not improve perioperative stress response in terms of catecholamine and stress hormones in laparoscopic gynecologic surgery performed in the steep Trendelenburg position despite the larger amount of opioid required to achieve adequate ANI values in the ANI group compared to the control group ANI guidance could not improve postoperative clinical outcomes When ANI monitoring is applied in laparoscopic surgeries in the Trendelenburg position strategies other than maintaining the target range of ANIm may be required The studies involving human participants were reviewed and approved by the Institutional Review Board of Yonsei University Health System approved this trial (#4-2020-0130) on April 1 The patients/participants provided their written informed consent to participate in this study drafting and critical revision of the manuscript All authors read and approved the final manuscript This research was supported by the Basic Science Research Program to JL through the National Research Foundation of Korea (NRF) funded by the Ministry of Science ICT & Future Planning (NRF-2019R1C1C1005201) The Supplementary material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/fmed.2023.1196153/full#supplementary-material Laparoscopic hysterectomy trends in challenging cases (1995-2018) Quality of life following minimally invasive hysterectomy compared to abdominal hysterectomy: a metanalysis Pain characteristics after Total laparoscopic hysterectomy Intraoperative "analgesia nociception index"-guided fentanyl administration during sevoflurane anesthesia in lumbar discectomy and laminectomy: a randomized clinical trial Objective monitoring of nociception: a review of current commercial solutions PubMed Abstract | CrossRef Full Text | Google Scholar Task force of the European Society of Cardiology and the north American Society of Pacing and Electrophysiology Heart rate variability: standards of measurement physiological interpretation and clinical use CrossRef Full Text | Google Scholar Google Scholar Cardiovascular effects of intraperitoneal insufflation with carbon dioxide and nitrous oxide in the dog Cardiopulmonary function and laparoscopic cholecystectomy CrossRef Full Text | Google Scholar Hemodynamic effects of head-down tilt in normal subjects and sustained hypertensive patients A targeted remifentanil administration protocol based on the analgesia nociception index during vascular surgery Analgesia nociception index (ani) monitoring in patients with thoracic paravertebral block: a randomized controlled study Benefits of intraoperative analgesia guided by the analgesia nociception index (ANI) in bariatric surgery: an unmatched case-control study Surgical Pleth index and analgesia nociception index for intraoperative analgesia in patients undergoing neurosurgical spinal procedures: a comparative randomized study Comparative study of analgesia nociception index (ANI) vs standard pharmacokinetic pattern for guiding intraoperative fentanyl administration among mastectomy patients Postoperative pain after laparoscopic cholecystectomy is not reduced by intraoperative analgesia guided by analgesia nociception index (ANI®) monitoring: a randomized clinical trial Analgesia nociception index-guided remifentanil versus standard care during Propofol anesthesia: a randomized controlled trial Sympatho-adrenal responses to general anesthesia in man and their relation to hemodynamics Catecholamine and cortisol responses to lower extremity revascularization: correlation with outcome variables Perioperative ischemia randomized anesthesia trial study group Perioperative catecholamine changes in cardiac risk patients CrossRef Full Text | Google Scholar Perioperative supplemental oxygen and plasma catecholamine concentrations after major abdominal surgery-secondary analysis of a randomized clinical trial Sevoflurane improves the neuroendocrine stress response during laparoscopic pelvic surgery The relationship among carbon dioxide pneumoperitoneum High intra-abdominal pressure increases plasma catecholamine concentrations during pneumoperitoneum for laparoscopic procedures Effects of pneumoperitoneum on cardiac autonomic nervous activity evaluated by heart rate variability analysis during sevoflurane Power spectral analysis of heart rate variability during positive pressure pneumoperitoneum: the significance of increased cardiac sympathetic expression Power spectral analysis of heart rate variability during helium pneumoperitoneum: the mechanism of increased cardiac sympathetic activity and its clinical significance Neuroendocrine stress response in gynecological laparoscopy: TIVA with propofol versus sevoflurane anesthesia The effects of combined epidural and general anesthesia on the autonomic nervous system and bioavailability of nitric oxide in patients undergoing laparoscopic pelvic surgery Steep Trendelenburg position during robotic sacrocolpopexy and heart rate variability Effects of pneumoperitoneum and the steep Trendelenburg position on heart rate variability and cerebral oxygenation during robotic Sacrocolpopexy Effects of laparoscopic radical prostatectomy on intraoperative autonomic nervous system control of hemodynamics Variations of the analgesia nociception index during general anaesthesia for laparoscopic abdominal surgery Guiding opioid administration by 3 different analgesia nociception monitoring indices during general anesthesia alters intraoperative Sufentanil consumption and stress hormone release: a randomized controlled pilot study Reduced postoperative pain using nociception level-guided fentanyl dosing during sevoflurane anaesthesia: a randomised controlled trial and renin responses to arterial hypotension in sheep PubMed Abstract | CrossRef Full Text | Google Scholar Changes in plasma concentration of adrenaline and noradrenaline in anaesthetized patients during sodium nitroprusside-induced hypotension Neural control of inflammation: implications for perioperative and critical care Remifentanil tolerance and hyperalgesia: short-term gain Kwon YI and Lee JH (2023) Effect of analgesia nociception index monitor-based nociception control on perioperative stress responses during laparoscopic surgery in Trendelenburg position: a randomized controlled trial Received: 29 March 2023; Accepted: 24 July 2023; Published: 04 August 2023 Copyright © 2023 Kim, Chang, Lee, Seo, Kwon and Lee. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) *Correspondence: Jae Hoon Lee, bmVvZ2Vuc0B5dWhzLmFj Disclaimer: All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article or claim that may be made by its manufacturer is not guaranteed or endorsed by the publisher. 94% of researchers rate our articles as excellent or goodLearn more about the work of our research integrity team to safeguard the quality of each article we publish. This study aimed to evaluate the impact of patients' positioning before and after intubation with mechanical ventilation, and after extubation on the lung function and blood oxygenation of patients with morbid obesity, who had a laparoscopic sleeve gastrectomy. Patients with morbid obesity (BMI ≥ 30 kg/m2, ASA I – II grade) who underwent laparoscopic sleeve gastrectomy at our hospital from June 2018 to January 2019 were enrolled in this prospective study. Before intubation, after intubation with mechanical ventilation, and after extubation, arterial blood was collected for blood oxygenation and gas analysis after posturing the patients at supine position or 30° reverse Trendelenburg position (30°-RTP). During and after laparoscopic sleeve gastrectomy, patients with morbid obesity had improved lung function, reduced pulmonary shunt, reduced PA−aO2 difference, and increased PaO2 and oxygen index at 30°-RTP compared to that supine position. Volume 9 - 2022 | https://doi.org/10.3389/fsurg.2022.792697 Background: This study aimed to evaluate the impact of patients' positioning before and after intubation with mechanical ventilation and after extubation on the lung function and blood oxygenation of patients with morbid obesity Methods: Patients with morbid obesity (BMI ≥ 30 kg/m2 ASA I – II grade) who underwent laparoscopic sleeve gastrectomy at our hospital from June 2018 to January 2019 were enrolled in this prospective study after intubation with mechanical ventilation arterial blood was collected for blood oxygenation and gas analysis after posturing the patients at supine position or 30° reverse Trendelenburg position (30°-RTP) Results: A total of 15 patients with morbid obesity were enrolled in this self-compared study Pulmonary shunt (Qs/Qt) after extubation was significantly lower at 30°-RTP (18.82 ± 3.60%) compared to that at supine position (17.13 ± 3.10% Patients' static lung compliance (Cstat) was significantly improved at 30°-RTP (36.8 ± 6.7) compared to that of those in a supine position (33.8 ± 7.3 The PaO2 and oxygen index (OI) before and after intubation with mechanical ventilation were significantly higher at 30°-RTP compared to that at supine position the PA−aO2 before and after intubation with mechanical ventilation was significantly reduced at 30°-RTP compared to that at supine position Conclusion: During and after laparoscopic sleeve gastrectomy patients with morbid obesity had improved lung function and increased PaO2 and oxygen index at 30°-RTP compared to that supine position the current study was designed to investigate if 30° reverse Trendelenburg position (30°-RTP) before and after intubation with mechanical ventilation as well as after extubation could improve the patient's oxygenation and lung function compared to supine position Inclusion criteria are as follows: (1) Patients who had laparoscopic sleeve gastrectomy in our hospital from June 2018 to January 2019 (2) patients with American Society of Anesthesiologists (ASA) grade I or II classifications (3) patients with a body mass index (BMI) ≥ 30 kg/m2 and (4) patients who have signed a written consent form Exclusion criteria are as follows: (1) Patients who have a history of severe cardiovascular diseases or severe hypovolemia; (2) patients who had a history of cerebrovascular diseases or cerebral ischemia; (3) Patients who had a history of chronic pulmonary diseases such as chronic obstructive pulmonary disease or respiratory failure; (4) Patients with severe anemia Hb < 90 g/L; and 5) Patients who had pneumonia within 30 days prior to the surgery Patients stopped eating at 12 h and drinking at 6 h prior to the surgery a Dash 5000 monitor was connected to obtain the patients' physiologic data that were included in the electrocardiogram and blood oxygenation index Blood pressure was measured through radial artery puncture and catheterization The patient was at supine position and given the following medicines by intravenous infusion: midazolam (0.12 mg/kg) Mechanical ventilation was then set as a pressure-controlled mode with 25–35 cm H2O airway pressure and 30–45 mmHg end-tidal partial pressure of carbon dioxide (PCO2) Sevoflurane was continuously inhaled during the operation and minimum alveolar concentration (MAC) was kept at 1.2–2 range Central vein puncture and catheterization were performed and cis-atracurium and sufentanil were periodically applied during the surgery to keep the desired anesthesia Sevoflurane inhalation was stopped once the surgery was completed Pre-intubation: upon entering the operation room the patient was put at supine position and given high flow oxygen (8 L/min) for 10 min followed by an arterial blood gas analysis the patient was postured at 30°-RTP and was given high flow oxygen (8 L/min) for 10 min followed by arterial blood gas analysis again On-ventilation: After completion of the surgery the patient was transferred to ICU with the support of mechanical ventilation at volume-controlled mode: 8 ml/kg tidal volume and 50% fraction of inspired oxygen (FiO2) arterial blood gas analysis and central vein blood gas analysis were performed at supine position The patient's position was then changed to 30°-RTP for 10 min followed by arterial and venous blood gas analysis Post-extubation: Patients emerged from general anesthesia in the ICU at supine position oxygen (50% FiO2) was delivered with a Venturi mask for 10 min followed by arterial and venous gas analysis The patient's position was then changed at 30°-RTP for 10 min followed by arterial and venous blood gas analysis again Blood gas analysis included the following parameters which were collected before the surgery: partial pressure of oxygen (PaO2) and alveolar-arterial oxygen tension difference (PA−aO2) at two different positions were collected after surgery when the patients were intubated with mechanical ventilation and PA−aO2 at two different positions after extubation were collected and analyzed A preliminary study revealed that at 30°-RTP and tidal volume with face mask ventilation increased over 40% This study was a self-compared and prospective clinical study By the criteria of two-tailed a = 0.05 significance level and 80% confidence range at least 12 participants were required to have sufficient statistical power for this study a total of 15 patients was enrolled with the prediction of 20% failure Student's t-test was used for comparison and p < 0.05 was considered as significant A total of 15 patients were enrolled in this study with the following demographic features: average age of 38 (18–52) years old; gender ratio of 9/6 (M/F); average height of 170 (159–182) cm; average weight of 108 (92–130) kg; average body mass index (BMI) of 37.4 (32.7–54) kg/m2; and ASA (I/II): 10/5 there was no significant difference in Qs/Qt between the two positions when the patients were on mechanical ventilation Qs/Qt was significantly lower at 30°-RTP (18.82 ± 3.60%) compared to that at supine position (17.13 ± 3.10% patients' static lung compliance (Cstat) during mechanical ventilation was significantly improved at 30°-RTP (36.8 ± 6.7%) compared to that at supine position (33.8 ± 7.3% Comparison of Qs/Qt (%) on mechanical ventilation and post-extubation In contrast, PA−aO2 at pre-intubation and on mechanical ventilation was significantly reduced at 30°-RTP compared to that at supine position (p < 0.05, Table 4). At either position, PA−aO2 was significantly increased when the patients were on mechanical ventilation or after 10 min post-extubation compared to that of pre-intubation (P < 0.01, Table 4) the impact of 30°-RTP on lung function in patients with obesity who had sleeve gastrectomy through laparoscopy It was found that post-extubation Qs/Qt was significantly lower at 30°-RTP compared to that at supine position that the patients' static lung compliance (Cstat) during mechanical ventilation was significantly improved at 30°-RTP compared to that at supine position that PaO2 and oxygen index before and after intubation for mechanical ventilation were significantly higher at 30°-RTP compared to that at supine position the PA−aO2 before and after intubation for mechanical ventilation was significantly reduced at 30°-RTP compared to that at supine position These findings suggested that when patients with obesity had laparoscopic gastrectomy the 30°-RTP could improve the static lung compliance and increase PaO2 and oxygenation compared to that at supine position Increased fat within the chest and abdominal wall causes a decrease in lung and chest wall compliance, increased airway resistance, and a reduced FRC (3, 21, 27). Closure of the airways leads to alveolar collapse, ventilation/perfusion mismatch, and hypoxia caused by pulmonary shunting (28, 29) artery blood was collected and analyzed before and after changing from supine position to 30°-RTP in patients with morbid obesity arterial PaO2 and oxygen index were increased at 30°-RTP arterial PaO2 and oxygen index were reduced when the patients were on mechanical ventilation under anesthesia These findings suggested that optimization of lung function is likely to be achieved by a posture that improves respiratory mechanics and arterial oxygen tension after intubation and on mechanical ventilation as well as during the emergence from general anesthesia and PA−aO2 were significantly higher at 30°-RTP than in supine position there were no significant differences between the two positions in the aforementioned parameters This could be due to patients falling asleep and airway collapse following extubation Pulmonary shunt (Qs/Qt) is 2–6% in a normal healthy person It is further exacerbated to be as high as 20% with general anesthesia and mechanical ventilation Qs/Qt was 17% when the patients with obesity were intubated and on mechanical ventilation After extubation in supine position though These findings suggested that severe oxygen desaturations and pulmonary shunt can be avoided by optimizing the position of the patient with the head and trunk elevation comparison of 30°-RTP in patients with morbid obesity who underwent laparoscopic sleeve gastrectomy vs Roux-en-Y gastric bypass remains to be conducted in future studies the current study demonstrated that the position of 30°-RTP was readily achievable in patients with morbid obesity during laparoscopic sleeve gastrectomy with mechanical ventilation It also demonstrated that patients' static lung compliance (Cstat) during mechanical ventilation significantly improved at 30°-RTP compared to that at supine position the patient's pulmonary shunt (Qs/Qt) and PA−aO2 were significantly reduced while PaO2 and oxygen indexes were significantly increased at 30°-RTP compared to that at supine position These findings suggested that a short period of 30°-RTP during and after laparoscopic sleeve gastrectomy could significantly improve lung functions in patients with morbid obesity The original contributions presented in the study are included in the article/supplementary material The studies involving human participants were reviewed and approved by the Ethics Committee of China-Japan Union Hospital of Jilin University and ZS contributed to the study conception and design contributed to the interpretation of the data contributed to the drafting of the article and final approval of the submitted version This work was supported by the Education Department of Jilin Province (No JJKH20170862KJ) and the Science and Technology Department of Jilin Province (No Trends in obesity among adults in the United States Obesity prevalence from a European perspective: a systematic review Metabolic profiling of visceral adipose tissue from obese subjects with or without metabolic syndrome Parathyroid hormone and insulin resistance in distinct phenotypes of severe obesity: a cross-sectional analysis in middle-aged men and premenopausal women and gas exchange during general anesthesia The effects of body mass index on lung volumes PubMed Abstract | CrossRef Full Text | Google Scholar Clinical effectiveness and cost-effectiveness of laparoscopic surgery for colorectal cancer: systematic reviews and economic evaluation A prospective case-matched comparison of clinical and financial outcomes of open versus laparoscopic colorectal resection The effects of the alveolar recruitment maneuver and positive end-expiratory pressure on arterial oxygenation during laparoscopic bariatric surgery Body image dissatisfaction in individuals with obesity seeking bariatric surgery: exploring the burden of new mediating factors Robotic versus laparoscopic versus open surgery in morbidly obese endometrial cancer patients - a comparative analysis of total charges and complication rates Long-term effects of laparoscopic sleeve gastrectomy versus Roux-en-Y gastric bypass for the treatment of morbid obesity: a monocentric prospective study with minimum follow-up of 5 years Frequent follow-up visits reduce weight regain in long-term management after bariatric sugery The effect of pneumoperitoneum and Trendelenburg position on respiratory mechanics during pelviscopic surgery Exploring the intraoperative lung protective ventilation of different positive end-expiratory pressure levels during abdominal laparoscopic surgery with Trendelenburg position Positive end-expiratory pressure and distribution of ventilation in Pneumoperitoneum combined with steep trendelenburg position Effect of age on pulmonary gas exchange during laparoscopy in the trendelenburg lithotomy position The effects of anesthesia and muscle paralysis on the respiratory system Pulmonary atelectasis: a pathogenic perioperative entity PubMed Abstract | CrossRef Full Text | Google Scholar Impact of the patient's body position on the intraabdominal workspace during laparoscopic surgery Perioperative management of the obese surgical patient What is the proper ventilation strategy during laparoscopic surgery PubMed Abstract | CrossRef Full Text | Google Scholar A new method in laparoscopic sleeve gastrectomy: reverse trendelenburg with right lateral tilt position prior to trocar entry Adverse events related to trendelenburg position during laparoscopic surgery: recommendations and review of the literature Preoxygenation is more effective in the 25 degrees head-up position than in the supine position in severely obese patients: a randomized controlled study A preliminary study of the optimal anesthesia positioning for the morbidly obese patient PubMed Abstract | CrossRef Full Text | Google Scholar and blood flow in obese patients with normal and abnormal blood gases PubMed Abstract | Google Scholar Respiratory management of the obese patient undergoing surgery Regional distribution of pulmonary ventilation and perfusion in obesity Weight history and all-cause and cause-specific mortality in three prospective cohort studies Association of metabolic syndrome and surgical factors with pulmonary adverse events and longitudinal mortality in bariatric surgery Morbid obesity and postoperative pulmonary atelectasis: an underestimated problem Expiratory flow limitation in morbidly obese postoperative mechanically ventilated patients Improvement of dyspnea after bariatric surgery is associated with increased expiratory reserve volume: a prospective follow-up study of 45 patients Yang Q and Su Z (2022) Impact of 30° Reserve Trendelenburg Position on Lung Function in Morbidly Obese Patients Undergoing Laparoscopic Sleeve Gastrectomy Received: 11 October 2021; Accepted: 21 January 2022; Published: 24 February 2022 Copyright © 2022 Gao, Sun, Wang, Shi, Song, Liu, Yang and Su. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY) *Correspondence: Zhenbo Su, c3V6YkBqbHUuZWR1LmNu †These authors have contributed equally to this work Metrics details no position modifications have been described for vitreoretinal surgery We report a positioning and surgical technique for pars plana vitrectomy in a severely kyphotic patient (a) Photograph of the patient standing upright in the clinic the patient was reclined in an office examination chair in order to determine his head position while supine the patient was placed in Trendelenburg position with towels under his head for extra support along with a stool placed under the operating table for added stability and safety (d) Temporal approach vitrectomy and lensectomy were performed with the patient in Trendelenburg position An in-office trial of Trendelenburg positioning can simulate the operating table Careful review of the patient’s ocular and medical history and planning with a multidisciplinary team can help achieve surgical goals while maximizing patient comfort and safety Cataract surgery in the patient that cannot lie flat Side saddle cataract surgery for patients unable to lie flat: learning from the past The effects of steep trendelenburg positioning on intraocular pressure during robotic radical prostatectomy Implications for postoperative visual loss: steep trendelenburg position and effects on intraocular pressure Download references This work was supported by That Man May See The authors declare no conflict of interest Download citation As the popularity of robotic urologic and gynecological procedures increases so is the need to put patients in the gravity-defying slide-inducing steep version of the Trendelenburg position That creates patient safety challenges for your OR staff says safety risks increase with the steepness of the angle and the duration of the procedure The literal gravity of the situation not only can cause the patient to slide down the table's surface and possibly tear skin along the way but also increases intraocular and intracranial pressures as well as risks of airway and facial edema "I've seen a few patients emerge from anesthesia with significant swelling around the eyes," says Ms we had to keep the patient intubated to let the swelling go down If a procedure is taking longer than three hours consider flattening the patient out for a few minutes to give their body a break." Particularly challenging is the lithotomy-Trendelenburg position — supine with legs separated which compresses the lateral side of the legs Green says surgeons at her facility often employ this position for robotic prostatectomies and she stresses the importance rooting out any inconsistencies "Adding extra safeguards and standardizing your Trendelenburg protocols is well worth the effort," says Ms "The last thing you want for a patient who trusts you to perform a complex surgery is to send them home with a positioning-related complication." The relationship between robotic surgery and inadvertent perioperative hypothermia is the subject of increased investigation Minimally invasive robotic surgeries were assumed to provide less risk of losing normothermia than traditional open surgeries but that assumption has been called into question A recent case study examined the relationship in the specific subspecialty of pediatric robotic pyeloplasty which requires placing patients in the left lateral and steep Trendelenburg position According to the study, published last June in the Journal of Neonatology & Clinical Pediatrics a seven-year-old male patient presented for robotic pyeloplasty The patient was pre-medicated with midazolam induced with propofol and maintained on low flow (1L/min) nitrous oxide sevoflurane (2%) with volume control ventilation (VCV) Pneumoperitoneum was created and maintained below 12mm Hg After the patient was positioned in left lateral and steep Trendelenburg position end tidal carbon dioxide (EtCO2) unexpectedly rose to a dangerous level of 45 to 55 mmHg Changes to ventilator settings did not alleviate the situation while peak inspiratory pressure (PIP) and plateau pressure rose to 32mm Hg and 28mm Hg The patient was shifted onto pressure-controlled which lowered EtCO2 to the range of 40 to 45mmHg the patient was not taking spontaneous breaths despite an hour passing since the last dose of relaxant and no signs of hypercapnia The patient's axillary temperature was 36°C and the patient was actively warmed for 30 minutes as the team theorized that hypothermia was behind the delayed awakening the patient was finally successfully extubated and shifted to the PACU The team regrouped to determine exactly what caused the delayed awakening and hypothermia electrolyte disturbances and drug overdoses Although the IV and irrigation fluids were warm and the patient was properly covered with warm sheets they concluded that the long duration of surgery resulted in prolonged exposure to the cold dry insufflating carbon dioxide used during laparoscopy They also cited research found exaggerated instances of intraoperative hypothermia in the head-down position "When dealing with pediatric patients or surgeries demanding accurate temperature monitoring due caution [should] be paid to the relationship between the measured temperature and the core temperature," say the researchers "This can guide us in an accurate assessment and efficient prevention of hypothermia." The preventive measures recommended by the researchers include active warming devices and heat humidifiers Insufflating gas flows should be warmed and kept below 2 L/min while a surgical humidification system should be used to humidify and warm the gas to about 37°C "There are various critical anesthetic concerns in robotic-assisted pediatric surgery," says the team close watch of the functional correlations complications can be minimized to achieve improved patient outcomes." CNOR is currently a consultant specializing in robotic program growth and development She has worked in the Las Vegas robotic market for the past 12 years for multiple organizations has been a guest speaker for Intuitive Surgical Inc and has taught robotic excellence courses across the country She believes every patient deserves the best minimally invasive procedure available and is passionate about driving robotic excellence She shares her insights about how to achieve the best patient experience You have to consider turn-over time; every minute on a robot is expensive staff safety during transfer can be an issue since normothermic patients have the best outcomes Justifying the expense of robotic surgery demands better outcomes but we had trouble with the integrity of the pads and worried about body weight shifting creating micro shear forces and pressure injuries I was concerned about infections as well as pressure injuries Then we tried a mechanical device with a frame and a foam safety bump at the neck and shoulder bolsters but I couldn't get 100% of my anesthesia providers to get onboard you really want to standardize as much as possible The anesthesia providers didn't like the mechanical device because of brachial-plexus injury concerns no matter what information and training I tried to provide for them I also found a group of our larger patients with neck and upper back anatomy that didn't allow for the safety bump to work causing some concern about workarounds to secure those patients WaffleGrip™ and HotDog™ are registered trademarks of Augustine Surgical Note: For more information go to https://hotdogwarming.com/wafflegrip-trendelenburg-positioner/ Eleanor Markle provides consulting to medical device companies Surgical teams should be aware of the higher-than-usual potential for patients in the reverse Trendelenburg position to develop deep vein thrombosis (DVT) during or following a procedure There is evidence in the literature that the reverse Trendelenburg position can significantly decrease a patient's femoral blood flow these patients are more likely to suffer venous stasis or blood pooling which can lead to blood clotting in the leg Mitigation strategies during prolonged surgeries include placement of a compression stocking over the patient's leg not just during surgery but until they're fully mobile after the procedure Another is the placement of an intermittent pneumatic compression device over the patient's leg to help improve blood flow by putting alternating amounts of pressure on the lower limb Best practices for DVT prevention may vary depending on the procedure types as well. For example, one study examines the conjunctive risks of high intra-abdominal pressure and the reverse Trendelenburg position during laparoscopic cholecystectomies Acting on the recommendation that pneumoperitoneum can help patients with limited cardiac pulmonary or renal reserves avoid venous stasis during these procedures they sought to determine exactly how much pressure should be applied Fifty patients were classified in two 25-patient groups One received high-pressure pneumoperitoneum (14 mmHg) and the other received low-pressure pneumoperitoneum (8 mmHg) Researchers detected that the changes in coagulation parameters were less significant at low-pressure pneumoperitoneum "This study provides evidence of using low-pressure pneumoperitoneum during laparoscopic cholecystectomies as changes in femoral vein hemodynamics and coagulation parameters were less pronounced." This and other research suggests that DVT concerns should be top-of-mind for OR staff during any extended Trendelenburg procedure Research shows heated irrigation fluids reduce risks of decreased body temperature and subsequent postoperative complications such as vasoconstriction of the blood vessels impaired oxygen delivery through altered chemotaxis and impairment of neutrophil and platelet function Researchers examined records of male patients who underwent endoscopic urology procedures between 2000 and 2016. These patients, usually 65 years or older, frequently receive irrigation fluids. The goal of the study, published in the Turkish Journal of Anaesthesiology & Reanimation was to determine if the use of heated irrigation fluids would lower incidences of hypothermia and related complications 1,369 received room temperature irrigation fluids and 264 received heated irrigation fluids Researchers found a temperature loss of 0.10°C in the room temperature group and an increase of 0.32°C in the heated group All patients involved were found to be normothermic with a temperature of at least 36°C in pre-op without documented preoperative warming efforts "The study revealed that warmed irrigation fluids do have a significant impact on the prevention of postoperative hypothermia," say the researchers the study failed to present any statistically significant changes in postoperative clinical outcomes." They theorized that the health system's use of warming blankets prevented temperature decreases significantly enough to impact postoperative outcomes heat-preserving policies that integrate the use of warmed fluids for irrigation emdash especially in patients undergoing higher risk surgeries emdash may be beneficial in decreasing unwanted events secondary to postoperative hypothermia," they conclude Metrics details We hypothesized that deep neuromuscular blockade (NMB) with low-pressure pneumoperitoneum (PP) would improve respiratory mechanics and reduce biotrauma compared to moderate NMB with high-pressure PP in a steep Trendelenburg position Seventy-four women undergoing robotic gynecologic surgery were randomly assigned to two equal groups Moderate NMB group was maintained with a train of four count of 1–2 and PP at 12 mmHg Deep NMB group was maintained with a post-tetanic count of 1–2 and PP at 8 mmHg Inflammatory cytokines were measured at baseline Interleukin-6 increased significantly from baseline at the end of PP and 24 h after the surgery in moderate NMB group but not in deep NMB group (Pgroup*time = 0.036) and mean airway pressures were significantly higher in moderate NMB group than in deep NMB group at 15 min and 60 min after PP (Pgroup*time = 0.002 deep NMB with low-pressure PP significantly suppressed the increase in interleukin-6 developed after PP by significantly improving the respiratory mechanics compared to moderate NMB with high-pressure PP during robotic surgery these results did not consider the depth of NMB at all there is still no clinical research on deep NMB combined with low-pressure PP that would improve the respiratory condition and reduce inflammation during mechanical ventilation We hypothesized that deep NMB combined with low-pressure PP would improve respiratory mechanics and then reduce biotrauma compared to moderate NMB combined with high-pressure PP during protective lung ventilation The aim of this study was to evaluate the effects of deep NMB combined with low-pressure PP and moderate NMB combined with high-pressure PP on respiratory mechanics and biotrauma during protective lung ventilation for robotic gynecologic surgery in a steep Trendelenburg position tumour necrosis factor receptor (TNFR)-1 (B) †P < 0.05 versus baseline in each group There was a significant interaction between group and time in Ppeak, Pplat, Pdriving, and Pmean (Table 2) Ppeak was significantly higher in the moderate NMB group than in the deep NMB group at 15 min Pplat and Pdriving were significantly higher in the moderate NMB group than in the deep NMB group at 15 min and 60 min after PP (P = 0.004 and P < 0.001 Pmean was significantly higher in the moderate NMB group than in the deep NMB group at 15 min and 60 min after PP (both P = 0.005) IAP was adequately maintained at approximately 8 or 12 mmHg throughout PP without changing the pressure level White blood cell counts and CRP levels were similar between the two groups (Table 3) The number of patients with CRP > 0.5 mg/dL was similar in the moderate and deep NMB groups [26 (79%) vs 30 (88%) The intergroup differences in changes in HR and PaO2/FiO2 ratio from baseline were comparable over time (Pgroup*time = 0.566 This randomized controlled trial is the first study to evaluate the effect of deep NMB combined with low-pressure PP on respiratory mechanics and biotrauma during protective lung ventilation against PP We demonstrated that in patients undergoing robotic gynecologic surgery deep NMB combined with low-pressure PP significantly suppressed the increase in IL-6 level developed after PP by significantly improving the respiratory mechanics compared with moderate NMB combined with high-pressure PP these studies were performed in reverse Trendelenburg position and did not consider the depth of NMB TNFR-1 levels increased significantly from baseline after PP in both groups and was significantly higher in the moderate NMB group than in the deep NMB group at the end of PP and 24 h after the surgery although there was no intergroup difference in the change in TNFR-1 level deep NMB combined with low-pressure PP significantly lowered Ppeak and thus it might suppress the inflammatory responses associated with ventilator-induced lung injury as compared with moderate NMB combined high-pressure PP deep NMB plus low-pressure PP significantly reduced biotrauma in our study the deep NMB combined with low-pressure PP significantly suppressed the increases in IL-6 level developed after PP by significantly improving the respiratory mechanics compared to moderate NMB combined with high-pressure PP in a steep Trendelenburg position during robotic gynecologic surgery After obtaining approval from the Ajou University Hospital Institutional Review Board (AJIRB-MED-OBS-18-115), this study was registered at http://clinicaltrials.gov (NCT 03576118) This study was performed in accordance with relevant guidelines and regulations 74 patients aged 25–80 years undergoing robotic gynecologic surgery with Trendelenburg position were enrolled All participants provided written informed consent prior to randomization The exclusion criteria were the presence of cerebrovascular disease and morbid obesity (body mass index > 35 kg/m2) Patients were randomly assigned to moderate or deep NMB groups using a computer-generated randomization technique (http://www.random.org) The moderate NMB group (n = 37) was maintained with a train of four (TOF) count of 1–2 and IAP at 12 mmHg during surgery and then reversed using glycopyrrolate (10 μg/kg) and neostigmine (50 μg/kg) after surgery The deep NMB group (n = 37) was maintained with a post-tetanic count of 1–2 and IAP at 8 mmHg and then reversed using sugammadex (4 mg/kg) NMB was monitored using acceleromyography (TOF-Watch-SX; MSD BV which was applied to the adductor pollicis muscle The study intervention was conducted by an anesthetic provider who did not participate in the outcome assessment Patients and outcome assessors of intraoperative and postoperative periods were blinded to the group assignment Anesthesia was maintained using propofol and remifentanil to achieve the BIS value of 40–60 and mean arterial pressure (MAP) within 20% of baseline Rocuronium (0.3–0.4 mg/kg/h) was continuously infused and titrated according to the group assignment until the end of the fascia suturing and extubation was done after confirming the TOF ratio > 0.9 Lactate Ringer’s solution or normal saline was infused at a rate of 6 ml/kg/h PP was controlled by limiting CO2 insufflator intravenous fentanyl was administered for 48 h at a rate of 0.4 µg/kg/h depending on the patient’s need Blood samples were collected at 3 time points: after induction (baseline) and 24 h after surgery; they were transferred to EDTA tubes and sent to the laboratory in a container They were centrifuged at 3600 rpm for 30 min and 1.5 mL of the supernatant serum was collected in an Eppendorf tube which was subsequently frozen at − 80 °C for later analysis The levels of cytokines were measured using a commercially available ELISA kit (R&D Systems Each sample was analyzed in triplicates and excluded when at least one was not determined including peak inspiratory pressure (Ppeak) were recorded at 4 time points: after induction (baseline) Driving airway pressure (Pdriving) means pressure gradient from the plateau pressure to PEEP and parameters associated with arterial blood gas analysis (pH and PaCO2) were recorded at 5 time points: after induction (baseline) The arterial blood samples were analyzed using a satellite blood-gas analyzer (Stat Profile pHOx Ultra White blood cell count was measured preoperatively and 24 h after surgery normal range ≤ 0.5 mg/dL) and chest X-ray were evaluated at 24 h after surgery we assumed that a 15% reduction in IL-6 level might be clinically significant With an α-error of 0.05 and a β-error of 90% We included 37 patients per group to allow for possible dropouts Values are expressed as mean (SD or standard error) or median [range (interquartile range)] or numbers of patients The normality of distribution was assessed with the Kolmogorov–Smirnov test Parametric data and nonparametric data were analyzed using the independent t test and the Mann–Whitney U test Categorical variables were evaluated using the chi-square test or Fisher’s exact test Intergroup comparisons for repeated-measures and cytokines were performed using a linear mixed model with post hoc analyses as fixed effects A P value < 0.05 was considered statistically significant Statistical analysis was conducted using SAS (version 9.3 Postoperative comparison of laparoscopic radical resection and open abdominal radical hysterectomy for cervical cancer patient Comparison of perioperative outcomes between pure laparoscopic surgery and open right hepatectomy in living donor hepatectomy: Propensity score matching analysis Robotic versus open pancreaticoduodenectomy: A meta-analysis of short-term outcomes Systematic review of oxidative stress associated with pneumoperitoneum Room air versus carbon dioxide pneumoperitoneum: Effects on oxidative state apoptosis and histology of splanchnic organs The European Association for Endoscopic Surgery clinical practice guideline on the pneumoperitoneum for laparoscopic surgery Deep neuromuscular block to optimize surgical space conditions during laparoscopic surgery: A systematic review and meta-analysis What is the evidence for the use of low-pressure pneumoperitoneum Biotrauma and ventilator-induced lung injury: Clinical implications Effect of combining a recruitment maneuver with protective ventilation on inflammatory responses in video-assisted thoracoscopic lobectomy: A randomized controlled trial Effects of intraoperative protective lung ventilation on postoperative pulmonary complications in patients with laparoscopic surgery: Prospective Impact of a lung-protective ventilatory strategy on systemic and pulmonary inflammatory responses during laparoscopic surgery: Is it really helpful? Neuromuscular blockers in early acute respiratory distress syndrome Effects of intra-abdominal pressure in rat lung tissues after pneumoperitoneum Stress response to laparoscopic surgery: A review A prospective randomized study of systemic inflammation and immune response after laparoscopic Nissen fundoplication performed with standard and low-pressure pneumoperitoneum Effects of low and high intra-abdominal pressure on immune response in laparoscopic cholecystectomy Randomized comparison between different insufflation pressures for laparoscopic cholecystectomy A comparative study of angiogenic and cytokine responses after laparoscopic cholecystectomy performed with standard- and low-pressure pneumoperitoneum Comparison of standard-pressure and low-pressure pneumoperitoneum in laparoscopic cholecystectomy: A double blinded randomized controlled study Inflammatory and immune responses to surgery and their clinical impact Novel anti-tumour necrosis factor receptor-1 (TNFR1) domain antibody prevents pulmonary inflammation in experimental acute lung injury Low vs standard pressures in gynecologic laparoscopy: A systematic review Evaluation of surgical conditions during laparoscopic surgery in patients with moderate vs deep neuromuscular block Effects of the pneumoperitoneum and Trendelenburg position on respiratory mechanics in the rats by the end-inflation occlusion method Effects of pneumoperitoneal pressure and position changes on respiratory mechanics during laparoscopic colectomy Driving pressure and survival in the acute respiratory distress syndrome Neuromuscular blocking agents decrease inflammatory response in patients presenting with acute respiratory distress syndrome Early neuromuscular blockade in moderate to severe acute respiratory distress syndrome: Do not throw the baby out with the bathwater! Neuromuscular blocking agents for acute respiratory distress syndrome: An updated meta-analysis of randomized controlled trials Rocuronium bromide inhibits inflammation and pain by suppressing nitric oxide production and enhancing prostaglandin E2 synthesis in endothelial cells Peritoneal morphological changes due to pneumoperitoneum: The effect of intra-abdominal pressure Preconditioning-like amelioration of erythropoietin against laparoscopy-induced oxidative injury Perioperative inflammation and its modulation by anesthetics Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome Comparison of the stress response in patients undergoing gynecological laparoscopic surgery using carbon dioxide pneumoperitoneum or abdominal wall-lifting methods Download references This work was supported in part by a research grant from the Investigator-Initiated Studies Program of Merck Sharp & Dohme Corp These authors contributed equally: Jong Yeop Kim and Hyun Jeong Kwak Department of Anesthesiology and Pain Medicine and H.J.K.; Provision of study materials or patients: S.K.M.; Collection and assembly of data: E.H and J.Y.K.; Data analysis and interpretation: J.E.K and H.J.K.; Final approval of manuscript: All authors Download citation DOI: https://doi.org/10.1038/s41598-021-81582-0 PDF Background To evaluate intraocular pressure (IOP) changes in patients undergoing robotic-assisted radical prostatectomy and to evaluate complications from increased IOP Methods Thirty-one eyes scheduled for robotic prostatectomy were included Perioperative IOP measurements were performed as follows: prior to induction of anaesthesia while supine and awake (T1); immediately post-induction while supine (T2); every hour from 0 to 5 h while anaesthetised in a steep Trendelenburg position (T3–T8); prior to awakening while supine (T9); and 30 min after awakening while supine (T10) A complete ophthalmic examination including visual acuity and retinal nerve fibre layer thickness (RNFL) was performed at enrolment and 1 month postoperatively Results Average IOP (mm Hg) for each time point was as follows: T1=18.0 The proportion of eyes with intraoperative IOP ≧30 mm Hg were as follows: T3=0% Mean visual acuity (logarithm of the minimal angle of resolution) and RNFL showed no statistically significant difference before and after operation and no other ocular complications were found at final examination Conclusions While IOP increased in a time-dependent fashion in anesthaetised patients undergoing robotic-assisted radical prostatectomy in a steep Trendelenburg position visual function showed no significant change postoperatively and no complications were seen Steep Trendelenburg positioning during time-limited procedures appears to pose little or no risk from IOP increases in patients without pre-existing ocular disease This is an Open Access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 3.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/3.0/ https://doi.org/10.1136/bjophthalmol-2013-303536 If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service You will be able to get a quick price and instant permission to reuse the content in many different ways Prostate cancer is the sixth most common cancer and the eighth leading cause of cancer death in Japan It is estimated that prostate cancer will be the second most common cancer by 2020 and various treatments for prostate cancer are now available in Japan robotic-assisted radical prostatectomy is one of the newest and most technically advanced modalities with advantages that include stereoscopic visualisation and good manoeuvrability within the operating area robotic-assisted surgery (da Vinci S HD Surgical System; Intuitive Surgical USA) began to be covered under government insurance from April 2012 Due to its surgical advantages in prostate cancer the number of robotic surgeries has increased from 667 in 2011 to 1800 by October 2012 Awad et al concluded that IOP reached peak levels after prolonged steep Trendelenburg positioning on average 13 mm Hg higher than pre-anaesthesia induction values intraoperative IOP changes and their adverse ocular effects have not been clarified yet The purpose of this study is thus to evaluate the IOP in patients who underwent robotic-assisted radical prostatectomy and to evaluate the effect on visual function by increased IOP A total of 31 consecutive patients scheduled for robotic prostatectomy were recruited at St Luke's International Hospital in Tokyo Japan from 20 January 2012 to 20 August 2012 All patients had their procedures performed within 1 month after recruitment Patients with preexisting glaucoma or retinal vascular diseases which may affect neuroretinal function or corneal diseases which may affect IOP measurement All aspects of this study were approved by the Institutional Review Board at the study site and informed consent was obtained from all patients Patients scheduled for prostatectomy visited our ophthalmology department 1 month prior to and after the operation A complete ophthalmic examination was performed at enrolment and again 1 month postoperatively including determination of best-corrected visual acuity (VA) IOP measurement in sitting position by Goldmann applanation tonometer and logarithm of the minimal angle of resolution (LogMAR) values were calculated for statistical analysis The gonioscopic examination was performed and evaluated by Scheie classification The anterior chamber was evaluated by the van Herick method only preoperatively The average retinal nerve fibre layer (RNFL) thickness and the inferior RNFL thickness imaged by the Cirrus HD-OCT (Carl Zeiss Meditec Inc USA) were calculated to detect RNFL progression IOP measurements were performed on each patient in both eyes with a Tono-pen XL handheld tonometer (Medtronic The tonometer was calibrated according to the manufacturer's guidelines before each reading Measurements were repeated if the variability between sequential measurements exceeded 5% The IOP was measured before induction of anaesthesia while supine and awake (T1) and immediately after induction while supine (T2) All patients were placed in a steep Trendelenburg position (23° after which IOP was measured every 1 h from (0 to 5 h) (T3–T8) Immediately after going back to the supine position postoperatively IOP was again measured during anaesthesia (T9) arterial blood pressure and blood loss were also recorded The anaesthesia protocol was standardised for drugs used during the procedure remifentanil and fentanyl were used for pain relief and rocuronium was used for mascular relaxation The primary endpoint of this study was change in IOP at each point; secondary endpoint was complication rate Only measurements from the left eye of each patient were included in this study Mixed linear models (change in IOP) and paired t-test (change in VA and RNFL thickness) were used to evaluate these outcomes Time-to-event analysis was performed to determine the cumulative hazard of IOP change at each time point during operation A p value less than 0.05 was considered statistically significant All analyses were done with SSPS V.15.0J (SPSS Japan Thirty-one male patients (31 eyes) were enrolled in this study and underwent robotic-assisted radical prostatectomy Patients’ ages ranged from 54 to 74 years old Twenty-nine of 31 eyes (93.5%) were grade IV by the van Herick method; 2 eyes (6.5%) were grade III 27 of 31 eyes (87.1%) were graded wide open by Scheie classification; 4 of 31 eyes (12.9%) were grade I Mean operation time was 4.57±0.03 h (range 3 h 47 min–6 h 9 min) Mean blood loss was 364±196 ml (80–810 mL) Mean blood pressure was 104.8±12.1/56.4±5.8 mm Hg at T4 Mean VA (LogMAR) was 0.088 preoperatively and 0.089 postoperatively with no statistically significant difference found before and after operation Twenty-eight of 31 eyes (90.3%) underwent OCT Mean average RNFL thickness was not significantly different before (91.0 μm) versus after (92.1 μm) the operation and inferior RNFL thickness was also not significantly different before (117.2 μm) versus after (117.2 μm) the operation No other ocular complications were found at final examination One month postoperative data from five patients were not able to be included due to loss to follow-up Mean (range) IOP was 13.2 mm Hg (8–20 mm Hg) preoperatively, 18.0 mm Hg (9–29 mm Hg) at T1, 9.8 mm Hg (4–15 mm Hg) at T2, 18.9 mm Hg (5–28 mm Hg) at T3, 21.6 mm Hg (15–31 mm Hg) at T4, 22.5 mm Hg (14–36 mm Hg) at T5, 22.3 mm Hg (9–33 mm Hg) at T6, 24.2 mm Hg (12–33 mm Hg; N=18) at T7, 24.0 mm Hg (14–34 mm Hg; N=4) at T8, 15.7 mm Hg (10–25 mm Hg) at T9, 17.9 mm Hg (8–26 mm Hg) at T10 and 13.2 mm Hg (8–18 mm Hg) postoperatively (figure 1) mean IOP was significantly lower at T2 (p < 0.001) and higher at T4 (p=0.005) mean IOP was significantly higher at T5 (p=0.03) The T8 value was not analysed due to a small sample size Scatter plot of mean intraocular pressure (IOP) at each time point IOP increases time dependently after steep Trendelenburg positioning (T3–T8) The proportions of eyes that change from baseline intraocular pressure (T1) at each time point This study showed that IOP increases time dependently after steep Trendelenburg positioning in anaesthetised patients undergoing robotic-assisted radical prostatectomy visual function (VA and RNFL thickness) showed no statistically significant changes The proportion of eyes with IOP ≥ 30 mm Hg ranged from 0% at T3 A total of 25.8% of eyes demonstrated an IOP change of 10mm Hg while a change of ≥15 mm Hg was seen in 12.9% VA and RNFL thickness did not change after versus before surgery Only one prior report by Awad et al2 has been published regarding change in IOP during robotic-assisted radical prostatectomy The current study is the first to assess IOP and change in IOP during operation and its effect on visual function via acuity and RNFL thickness Awad et al reported that anesthaetised patients had a mean IOP of 25.2 mm Hg measured by a Tono-pen XL handheld tonometer in steep Trendelenburg position (25° increased to 29.0 mm Hg while still in steep Trendelenburg at the end of the procedure The reason for higher mean IOP compared with the present study remains unclear although it is possible that this may reflect a racial difference As CO2 gas is typically used to induce pneumoperitoneum during robotic surgery the authors estimated that continuous absorption of intraperitoneal CO2 and increased pressure on the diaphragm resulted in lower delivered tidal volumes and subsequently increased arterial PCO2 levels This may lead to increased choroidal blood volume and increased IOP The overall cumulative hazard to reach an IOP ≥ 30 mm Hg after 24 h was 23.9% The overall cumulative hazard to reach IOP ≥ 30 mm Hg after 5 h was 20%; no patients reached an IOP ≥ 40 mm Hg Our data suggest that IOP elevation may be limited during robotic-assisted radical prostatectomy compared with other treatments In 2007, Weber et al1 first reported a case of a 62-year-old patient who developed posterior ischaemic optic neuropathy after a robotic-assisted procedure lasting 6 h 35 min and with blood loss of 1200 mL the mean operation time was 4.57±0.03 h with mean blood loss of 364±196 mL the long operation time and large quantity of blood loss may be related to the occurrence of ischaemic optic neuropathy no patient experienced any ocular complications related to IOP increase IOP was noted to increase in a time-dependent fashion this suggests that longer operation times may induce substantially more risk for harmful IOP increases More aggressive evaluation for elevated IOP may be warranted when operation times exceed 5 h IOP would change much more with a larger head down degree patients with advanced glaucoma may not be good candidates for robotic surgery; thorough informed consent is prudent before robotic surgery because of the risk of ocular complications It should be mentioned that the relatively small number of patients in this study may limit the study conclusions as an ophthalmic examination was performed at only 1 month postoperatively a reversible adverse effect can occur within this 1-month time period these data suggest that further study is necessary to ascertain IOP increase and its effect on visual function in the setting of extreme surgical positioning we found that IOP increased in a time-dependent fashion in anaesthetised patients undergoing robotic-assisted radical prostatectomy in a steep Trendelenburg position Provenance and peer review Not commissioned; externally peer reviewed Metrics details Electrical impedance tomography (EIT) reconstructs functional lung images and evaluates the variations of impedance during the breathing cycle The aim of this study was to evaluate the effect of protective mechanical ventilation on ventilation distributions recorded by the EIT during elective robotic-assisted laparoscopy surgery with steep Trendelenburg position randomized single center study included patients with healthy lungs undergoing elective robot-assisted laparoscopic urological surgery in general anesthesia Patients were randomly assigned to either protective lung ventilation or conventional ventilation tidal volume (TV) was set at 6 ml/Kg predicted body weight (PBW) Ventilation distribution was assessed using an EIT device This study included 40 patients in the functional image analysis Significant differences were found in ventilation distribution in the region of interest (p < 0.05) Driving pressure was significantly lower in protective ventilation group (p < 0.05) Peak and plateau pressures were not different between the groups while statical significance was found in tidal volume and respiratory rate EIT may be a valuable tool for monitoring lung function during general anesthesia During elective robotic-assisted laparoscopy surgery with steep Trendelenburg position protective mechanical ventilation may have a more homogenous distribution of intraoperative and postoperative ventilation Larger sample size and long-term evaluation are needed in future studies to assess the benefit of EIT monitoring in operation room Clinical trial registration ClinicalTrials.gov Identifier: NCT04194177 registered at 11th December 2019 the aim of this study is to evaluate the effect of protective mechanical ventilation on ventilation distributions recorded by the EIT during elective robotic-assisted laparoscopy surgery with steep Trendelenburg position randomized single center study was approved by the local ethics committee (University of Naples “Federico II”—no132/17) and registered in clinical trial.org where the full protocol was available (NCT04194177—11/12/2019) The study was conducted from March 2020 to April 2022 All procedures were performed in accordance with the Declaration of Helsinki Informed consent of all patients was obtained before inclusion Patients were included if they have healthy lungs American Society of Anesthesiologists physical status (ASA) ≥ 2 undergoing elective robot-assisted laparoscopic prostatectomy surgery The presence of chronic pulmonary disease or other obstructive or restrictive disease congestive heart failure New York Heart Association (NYHA) III/IV BMI ≥ 35 and ventricular tachyarrhythmias were exclusion criteria General anesthesia was conducted in both groups as follow After premedication with midazolam (0.05 mg/kg) anaesthesia was induced with sufentanil (0.2 mcg/kg) propofol (2 mg/kg) and rocuronium (0.6 mg/kg) and maintained with desflurane adjusted to achieve minimum alveolar concentration (MAC) 0.8 rocuronium (0.15 mg/kg) train of four (TOF) guided Schematic diagram of study protocol and interventions for both groups.TV: tidal volume Ethical committee of university of Naples Federico II approved the study protocol (123/17) Written informed consent was obtained from each patient or next of kin To reach a power of 80% with an alpha error 0.05 we had to include 12 patients for each group Data were analyzed by Shapiro test to investigate the normal distribution; parametric data were presented as mean and standard deviation non-parametric data as median and interquartile range and proportions were compared with χ2 or Fisher exact test p values < 0.05 were considered statistically significant Analyses were performed with SPSS 20.0 (SPSS Corp EIT distribution of lung ventilation during protective mechanical ventilation. Regional distribution of tidal breath is visualized with a color scale based on calculated impedance changes during one breath. Brighter color (corresponding to large impedance change) shows a well-ventilated area. Darker color (small impedance change) shows a less ventilated area. EIT distribution of lung ventilation during conventional mechanical ventilation. Regional distribution of tidal breath is visualized with a color scale based on calculated impedance changes during one breath. Brighter color (corresponding to large impedance change) shows a well-ventilated area. Darker color (small impedance change) shows a less ventilated area. (A) EIT distribution of lung ventilation during protective and conventional mechanical ventilation over time (B) Distribution of driving pressure ventilation during protective and conventional mechanical ventilation over time Ppeak and Pplat pressures were not different between the groups while statical significance was found in tidal volume and respiratory rate and lung compliance at certain time (Table 2) In this randomized controlled study we found that lung protective ventilation applied during elective robotic-assisted laparoscopy surgery with steep Trendelenburg position improved ventilation distribution recorded by EIT and reduced driving pressure Our study sustained the evidence that protective mechanical ventilation with an adequate PEEP level improved the distribution of ventilation evaluated by the EIT during general anesthesia Even if a drop in tidal volume distribution was seen in both groups after induction and anesthesia the protective ventilation group had a homogeneous distribution of ventilation from the beginning of the Trendelenburg position to come back in supine position the protective ventilation group showed a better ventilation distribution also at the extubation and follow-up only after the extubation we found that EIT-derived parameters and driving pressure came back to the pre-anesthesia levels suggesting that persistent atelectasis and a ventilation–perfusion mismatch were present until the end of general anesthesia this is the first randomized controlled study evaluating the use of EIT during elective robotic-assisted laparoscopy surgery with steep Trendelenburg position the recruitment of 40 patients exceeds the estimated sample size (24 patients) this study may be a proof of concept that EIT may be used as respiratory monitoring in operation room the electrical interferences caused by the use of the electrocautery affected EIT measurements and impaired their interpretation making it necessary to exclude these breaths EIT belt positioning was a key factor in measurement consistency the possible clinical impact of our intervention was not evaluated since was not an aim of this study protocol Larger sample size and long-term evaluations are needed in future studies to assess the benefit of EIT monitoring in operation room Data and materials are available from the corresponding author after request Impaired oxygenation in surgical patients during general anesthesia with con-trolled ventilation: A concept of atelectasis Protective mechanical ventilation in the non-injured lung: Review and meta-analysis Incidence of mortality and morbidity related to postoperative lung injury in patients who have undergone abdominal or thoracic surgery: A systematic review and meta-analysis ; LAS VEGAS Investigators; PROVE Network; Clinical Trial Network of the European Society of Anaesthesiology Intraoperative ventilation settings and their associations with postoperative pulmonary complications in obese patients practice of ven- tilation and outcome for patients at increased risk of postoperative pulmonary complications: Las Vegas—An observational study in 29 countries and hospital stay following noncardiothoracic surgery: A multicenter study by the perioperative research network investigators The increasing call for protective ventilation during anesthesia Acute Respiratory Distress Syndrome Network Association between use of lung-protective ventilation with lower tidal volumes and clinical outcomes among patients without acute respiratory distress syndrome: A meta-analysis A trial of intraoperative low-tidal-volume ventilation in abdominal surgery Protective mechanical ventilation during general anesthesia for open abdominal surgery improves postoperative pulmonary function Effect of carbon dioxide pneumo- peritoneum on development of atelectasis during anesthesia New concepts of atelectasis during general anaesthesia Effects of carbon dioxide insufflation for laparoscopic cholecystectomy on the respiratory system Perioperative assessment of regional ventilation during changing body positions and ventilation conditions by electrical impedance tomography Positive end-expiratory pressure and distribution of ventilation in pneumoperitoneum combined with steep trendelenburg position Effect of PEEP on regional ventilation during laparoscopic surgery monitored by electrical impedance tomography Impact of PEEP during laparoscopic surgery on early postoperative ventilation distribution visualized by electrical impedance tomography PEEP role in ICU and operating room: From pathophysiology to clinical practice Comparison of low and high positive end-expiratory pressure during low tidal volume ventilation in robotic gynaecological surgical patients using electrical impedance tomography: A randomised controlled trial Mechanical ventilation and intra-abdominal hypertension: “Beyond Good and Evil” Double lumen endotracheal tube for percutaneous tracheostomy Download references Christian Bozsak for the assistance in this paper Reproductive and Odontostomatological Sciences wrote the draft and approved the final version of the paper Download citation DOI: https://doi.org/10.1038/s41598-023-29860-x This website is using a security service to protect itself from online attacks The action you just performed triggered the security solution There are several actions that could trigger this block including submitting a certain word or phrase You can email the site owner to let them know you were blocked Please include what you were doing when this page came up and the Cloudflare Ray ID found at the bottom of this page Please enable JS and disable any ad blocker Start Your Plant-Based Journey For $8/month* With The Forks Meal Planner! 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