Impact of Either Trendelenburg or Reverse Trendelenburg Positioning for Ureteroscopy Lithotripsy Procedures: A Systematic Review and Meta-Analysis.

PURPOSE: Urologists encounter multiple challenges in managing ureteral stones with ureteroscopic laser lithotripsy. This meta-analysis assesses the effectiveness of alternative surgical positioning, Reverse Trendelenburg (RevTren) and Trendelenburg (Tren), in reducing stone migration and enhancing outcomes compared to standard dorsal lithotomy positioning. MATERIALS AND METHODS: A systematic review was conducted following PRISMA guidelines, searching Medline, Embase, Scopus, Cochrane, and WoS up to March 2024. The review focused on studies evaluating RevTren or Tren positioning during ureteroscopic lithotripsy compared to standard dorsal lithotomy, analyzing endpoints such as stone migration, conversion rates, success rates, complications, and operative time. RESULTS: Out of 137 studies identified, 8 met the inclusion criteria, encompassing 1374 patients. RevTren significantly reduced ureteral stone migration (odds ratio [OR] 0.20, 95% confidence interval [CI] [0.08, 0.47]), lowered the need for conversion to a flexible ureteroscope (OR 0.28, 95% CI [0.12, 0.67]), and improved success rates (OR 2.90, 95% CI [1.88, 4.48]). Tren increased migration of ureteral and calyceal stones towards upper renal calyces (OR 2.12, 95% CI [1.48, 3.04]) and achieved a higher success rate (OR 3.56, 95% CI [2.15, 5.92]). Complications were comparable across all positions. CONCLUSION: Adjusting patient positioning during ureteroscopic laser lithotripsy can enhance procedure outcomes. RevTren effectively reduces ureteral stone migration and the necessity for flexible ureteroscopes, while Tren facilitates ureteral and calyceal stone migration towards upper calyces, increasing success rates. Both positioning techniques offer significant advantages over standard positioning and can be safely adopted in clinical practice without compromising patient safety.

Role of oxygen reserve index monitoring in patients undergoing robot-assisted radical prostatectomy: a retrospective study.

PURPOSE: Robot-assisted radical prostatectomy (RARP) is a common surgical procedure for the treatment of prostate cancer. Although beneficial, it can lead to intraoperative hypoxia due to high-pressure pneumoperitoneum and Trendelenburg position. This study explored the use of oxygen reserve index (ORi) to monitor and predict hypoxia during RARP. METHODS: A retrospective analysis was conducted on 329 patients who underwent RARP at the Seoul National University Bundang Hospital between July 2021 and March 2023. Various pre- and intraoperative variables were collected, including ORi values. The relationship between ORi values and hypoxia occurrence was assessed using receiver operating characteristic curves and logistic regression analysis. RESULTS: Intraoperative hypoxia occurred in 18.8% of the patients. The receiver operating characteristic curve showed a satisfactory area under the curve of 0.762, with the ideal ORi cut-off value for predicting hypoxia set at 0.16. Sensitivity and specificity were 64.5% and 75.7%, respectively. An ORi value of < 0.16 and a higher body mass index were identified as independent risk factors of hypoxia during RARP. CONCLUSIONS: ORi monitoring provides a non-invasive approach to predict intraoperative hypoxia during RARP, enabling early management. Additionally, the significant relationship between a higher body mass index and hypoxia underscores the importance of individualized patient assessment.

Evaluation of the effect of trendelenburg position duration on intracranial pressure in laparoscopic hysterectomies using ultrasonographic optic nerve sheath diameter measurements.

BACKGROUND: During laparoscopic surgery, pneumoperitoneum and Trendelenburg positioning applied to provide better surgical vision can cause many physiological changes as well as an increase in intracranial pressure. However, it has been reported that cerebral autoregulation prevents cerebral edema by regulating this pressure increase. This study aimed to investigate whether the duration of the Trendelenburg position had an effect on the increase in intracranial pressure using ultrasonographic optic nerve sheath diameter (ONSD) measurements. METHODS: The near infrared spectrometry monitoring of patients undergoing laparoscopic hysterectomy was performed while awake (T0); at the fifth minute after intubation (T1); at the 30th minute (T2), 60th minute (T3), 75th minute (T4), and 90th minute (T5) after placement in the Trendelenburg position; and at the fifth minute after placement in the neutral position (T6). RESULTS: The study included 25 patients. The measured ONSD values were as follows: T0 right/left, 4.18±0.32/4.18±0.33; T1, 4.75±0.26/4.75±0.25; T2, 5.08±0.19/5.08±0.19; T3, 5.26±0.15/5.26±0.15; T4, 5.36±0.11/5.37±0.12; T5, 5.45±0.09/5.48±0.11; and T6, 4.9±0.24/4.89±0.22 ( p < 0.05 compared with T0). ). No statistical difference was detected in all measurements in terms of MAP, HR and ETCO2 values compared to the T0 value (p > 0.05). CONCLUSIONS: It was determined that as the Trendelenburg position duration increased, the ONSD values ​​increased. This suggests that as the duration of Trendelenburg positioning and pneumoperitoneum increases, the sustainability of the mechanisms that balance the increase in intracranial pressure becomes insufficient. TRIAL REGISTRATION: This study was registered at Clinical Trials.gov on 21/09/2023 (registration number NCT06048900).

Factors related to clearance of the small pelvic cavity during gynecologic laparoscopic surgery.

AIM: To identify factors influencing the Trendelenburg angle required during laparoscopic gynecological surgery. METHODS: Patients who underwent laparoscopic surgery at a single university hospital between May 1, 2019, and March 31, 2021 were enrolled. Data were extracted from the medical records, while magnetic resonance imaging scans and all laparoscopic surgery videos were retrospectively reviewed to assess the presence of the small intestine in the pelvic cavity as well as the adhesions at each site. Groups with and without the small intestine in the pelvic cavity, and those requiring a Trendelenburg angle above or below 13° were compared. RESULTS: In total, 219 patients were examined. The Trendelenburg angle was significantly higher (p = 0.004), while a significant increase in ovarian adhesions was observed (p = 0.033; odds ratio [OR], 2.30; 95% confidence interval [CI], 1.05-5.01) in the group without the presence of the small intestine in the pelvic cavity. Furthermore, the group requiring a Trendelenburg angle of ≥13° had significantly thicker subcutaneous fat (p = 0.044) and more ileal adhesions (p = 0.040, OR, 1.82; 95% CI, 1.03-3.23) than the group with an angle of <13°. CONCLUSION: Cases of ileal adhesions or thick subcutaneous fat are more likely to require a Trendelenburg angle of ≥13°. Therefore, Trendelenburg complications should be considered in this group. In addition, ovarian adhesions make it more difficult to exclude the small intestine from the small pelvic cavity, and may be associated with endometriosis.

Lower extremity pain and/or numbness after laparoscopic surgery and robot-assisted surgery in the lithotomy position combined with the Trendelenburg position.

PURPOSE: The purpose of this study was to investigate the incidence and risk factors of lower extremity pain and/or numbness after laparoscopic colorectal surgery and robot-assisted laparoscopic radical prostatectomy in the lithotomy position combined with the Trendelenburg position. The relationship between creatine kinase (CK) levels and lower extremity pain and/or numbness was also investigated. METHODS: We retrospectively reviewed adult patients who underwent laparoscopic colorectal surgery and robot-assisted laparoscopic radical prostatectomy in the lithotomy position combined with the Trendelenburg position between May 2015 and April 2020. Logistic regression analysis was used to identify risk factors of lower extremity pain and/or numbness. Preoperative and postoperative CK levels were compared in patients with and those without lower extremity pain and/or numbness. RESULTS: Among 940 patients, 1.9% experienced lower extremity pain and/or numbness postoperatively. The incidences of lower extremity pain and/or numbness after laparoscopic colorectal surgery and after robot-assisted laparoscopic radical prostatectomy were 1.7% and 2.1%, respectively. Multivariate logistic regression analysis revealed that only duration of surgery > 4 h (odds ratio = 3.144, 95% CI: 1.102-8.969, p = 0.032) was a significant predictor of lower extremity pain and/or numbness. Postoperative median CK level in patients with lower extremity pain and/or numbness was significantly higher than that in patients without lower extremity pain and/or numbness. CONCLUSION: The incidence of lower extremity pain and/or numbness after laparoscopic colorectal surgery was comparable to that after robot-assisted laparoscopic radical prostatectomy. Prolonged duration of surgery contributed to lower extremity pain and/or numbness. Significantly elevated CK levels in patients with lower extremity pain and/or numbness suggest the involvement of muscle injury in these symptoms.

Ventilation strategy during urological and gynaecological robotic-assisted surgery: a narrative review.

Robotic-assisted surgery has improved the precision and accuracy of surgical movements with subsequent improved outcomes. However, it requires steep Trendelenburg positioning combined with pneumoperitoneum that negatively affects respiratory mechanics and increases the risk of postoperative respiratory complications. This narrative review summarises the state of the art in ventilatory management of these patients in terms of levels of positive end-expiratory pressure (PEEP), tidal volume, recruitment manoeuvres, and ventilation modes during both urological and gynaecological robotic-assisted surgery. A review of the literature was conducted using PubMed/MEDLINE; after completing abstract and full-text review, 31 articles were included. Although different levels of PEEP were often evaluated within a protective ventilation strategy, including higher levels of PEEP, lower tidal volume, and recruitment manoeuvres vs a conventional ventilation strategy, we conclude that the best PEEP in terms of lung mechanics, gas exchange, and ventilation distribution has not been defined, but moderate PEEP levels (4-8 cm H2O) could be associated with better outcomes than lower or highest levels. Recruitment manoeuvres improved intraoperative arterial oxygenation, end-expiratory lung volume and the distribution of ventilation to dependent (dorsal) lung regions. Pressure-controlled compared with volume-controlled ventilation showed lower peak airway pressures with both higher compliance and higher carbon dioxide clearance. We propose directions to optimise ventilatory management during robotic surgery in light of the current evidence.

Haemodynamic and respiratory perioperative outcomes for open versus robot-assisted radical cystectomy: A double-blinded, randomised trial.

BACKGROUND: The clinical impact of prolonged steep Trendelenburg position and CO2 pneumoperitoneum during robot-assisted radical cystectomy (RC) on intraoperative conditions and immediate postoperative recovery remains to be assessed. The current study investigates intraoperative and immediate postoperative outcomes for open RC (ORC) versus robot-assisted RC with intracorporal urinary diversion (iRARC) in a blinded randomised trial. We hypothesised that ORC would result in a faster haemodynamic and respiratory post-anaesthesia care unit (PACU) recovery compared to iRARC. METHODS: This study is a predefined sub-analysis of a single-centre, double-blinded, randomised feasibility study. Fifty bladder cancer patients were randomly assigned to ORC (n = 25) or iRARC (n = 25). Patients, PACU staff, and ward personnel were blinded to the surgical technique. Both randomisation arms followed the same anaesthesiologic procedure, fluid treatment plan, and PACU care. The primary outcome was immediate postoperative recovery using a standardised PACU Discharge Criteria (PACU-DC) score. Secondary outcomes included respiration- and arterial O2 saturation scores as well as perioperative interventions and recordings. RESULTS: All patients underwent the allocated treatment. The total PACU-DC score was highest 6 h postoperatively with no difference in the total score between randomisation arms (p = 0.80). Both the ORC and iRARC groups maintained a mean respiration- and arterial O2 saturation score below 1 (out of 3) throughout PACU stay. The iRARC patients had significantly, but clinically acceptable, higher maximum airway pressure and arterial blood pressure, as well as lower minimum pH levels. The ORC group received significantly more opioids after extubation but marginally less analgesics in the PACU, compared to the iRARC group. CONCLUSIONS: A prolonged Trendelenburg position and CO2 pneumoperitoneum was well-tolerated during iRARC, and immediate postoperative recovery was similar for ORC and iRARC patients.

Measuring intraoperative anesthetic parameters during hepatectomy with inferior vena cava clamping.

PURPOSE: Uncontrollable bleeding remained problematic in anatomical hepatectomy exposing hepatic veins. Based on the inferior vena cava (IVC) anatomy, we attempted to analyze the hemodynamic and surgical effects of the combined IVC-partial clamp (PC) accompanied with the Trendelenburg position (TP). METHODS: We prospectively assessed 26 consecutive patients who underwent anatomical hepatectomies exposing HV trunks between 2020 and 2023. Patients were divided into three groups: use of IVC-PC (group 1), no use of IVC-PC (group 2), and use of IVC-PC accompanied with TP (group 3). In 10 of 26 patients (38%), hepatic venous pressure was examined using transhepatic catheter insertion. RESULTS: IVC-PC was performed in 15 patients (58%). Operating time and procedures did not significantly differ between groups. A direct hemostatic effect on hepatic veins was evaluated in 60% and 70% of patients in groups 1 and 3, respectively. Group 1 showed significantly more unstable vital status and vasopressor use (p < 0.01). Blood or fluid transfusion and urinary output were similar between groups. Group 2 had a significantly lower baseline central venous pressure (CVP), while group 3 showed a significant increase in CVP in TP. CVP under IVC-PC seemed lower than under TP; however, not significantly. Hepatic venous pressure did not significantly differ between groups. Systolic arterial blood pressure significantly decreased via IVC-PC in group 1 and to a similar extent in group 3. Heart rate significantly increased during IVC-PC (p < 0.05). CONCLUSION: IVC-PC combined with the TP may be an alternative procedure to control intrahepatic venous bleeding during anatomical hepatectomy exposing hepatic venous trunks.

Improving Trendelenburg position effectiveness by varying cardiopulmonary bypass flow.

INTRODUCTION: Trendelenburg position (TP) is used to transport gaseous emboli away from the cerebral region during cardiac surgery. However, TP effectiveness has not been fully considered when combined with varying the cardiopulmonary bypass (CPB) flow. This study simulated the supine and TP at different pump flows and assessed the trapped emboli and embolic load entering the aortic arch branch arteries (AABA). METHODS: A computational fluid dynamics (CFD) approach used a centrally cannulated adult patient-specific aorta model replicating a CPB circuit. Air emboli of 0.1 mm, 0.5 mm, and 1.0 mm (n = 700 each) were injected into the aorta placed in the supine position (0°) and the TP (-20°) at 2 L/min and 5 L/min. The number of emboli entering the AABA were compared. An aortic phantom flow experiment was performed to validate air bubble behaviour. RESULTS: TP at 5 L/min had the lowest 0.1 mm mean (±SD) embolic load compared to the supine 2 L/min (55.3 ± 30.8 vs 64.3 ± 35.4). For both the supine and TP, the lower flow of 2 L/min had the highest number of simulated trapped emboli in higher elevated regions than at 5 L/min (541 ± 185 and 548 ± 191 vs 520 ± 159 and 512 ± 174), respectively. The flow experiment demonstrated that 2 L/min promoted bubble coalescence and high amounts of trapped emboli and 5 L/min transported air emboli away from the AABA. CONCLUSIONS: TP effectiveness was improved by using CPB flow to manage air emboli. These results provide insights for predicting emboli behaviour and improving emboli de-airing procedures.

Advances in the Clinical Application of Trendelenburg Position.

The Trendelenburg position and reverse Trendelenburg position are frequently employed during lower abdominal surgery to achieve optimal surgical field visualization and complete exposure of the operative site, particularly under pneumoperitoneum conditions. However, these positions can have significant impacts on the patient's physiological functions. This article overviews the historical background of Trendelenburg position and reverse Trendelenbury position, their effects on various physiological functions, recent advancements in their clinical applications, and strategies for preventing and managing associated complications.

[Effect of preoperative carbohydrates intake on the gastric volume and the risk of reflux aspiration in patients positioning in trendelenburg undergoing gynecological laparoscopic procedures].

OBJECTIVE: To investigate the effect of 300 mL carbohydrates intake two hours before sur-gery on the gastric volume (GV) in patients positioning in trendelenburg undergoing gynecological laparoscopic procedures by using gastric antrum sonography, and further assess the risk of reflux aspiration. METHODS: From June 2020 to February 2021, a total of 80 patients, aged 18-65 years, body mass index (BMI) 18-35 kg/m2, falling into American Society of Anesthesiologists (ASA) physical status Ⅰ or Ⅱ, scheduled for gynecological laparoscopic procedures positioning in trendelenburg were recruited and divided into two groups: the observation group (n =40) and the control group (n=40). In the observation group, solid food was restricted after 24:00, the patients were required to take 300 mL carbohydrates two hours before surgery. In the control group, solid food and liquid intake were restricted after 24:00 the night before surgery. The cross-sectional area (CSA) of gastric antrum was measured in supine position and right lateral decubitus position before anesthesia. Primary outcome was gastric volume (GV) in each group. Secondary outcome included Perlas A semi-quantitative grading and gastric volume/weight (GV/W). All the patients received assessment of preoperative feeling of thirsty and hunger with visual analogue scale (VAS). RESULTS: Complete data were available in eighty patients. GV was (58.8±23.6) mL in the intervention group vs. (56.3±22.1) mL in the control group, GV/W was (0.97±0.39) mL/kg vs. (0.95±0.35) mL/kg, respectively; all the above showed no significant difference between the two groups (P > 0.05). Perlas A semi-quantitative grading showed 0 in 24 patients (60%), 1 in 15 patients (37.5%), 2 in 1 patient (2.5%) in the intervention group and 0 in 25 (62.5%), 1 in 13 (32.5%), 2 in 2 (5%) in the control group, the proportion of Perlas A semi-quantitative grading showed no significant difference between the two groups (P > 0.05). A total of 3 patients (1 in the intervention group and 2 in the control group) with Perlas A semi-quantitative grading 2 were treated with special intervention, no aspiration case was observed in this study. The observation group endured less thirst and hunger (P＜0.05). CONCLUSION: Three hundred mL carbohydrates intake two hours before surgery along with ultrasound guided gastric content monitoring does not increase gastric volume and the risk of reflux aspiration in patients positioning in trendelenburg undergoing gynecological laparoscopic surgery, and is helpful in minimizing disturbance to the patient's physiological needs, therefore leading to better clinical outcome.

Inner ear barotrauma: A case report of rare post-operative complication following robot-assisted radical prostatectomy.

To highlight a rare case of inner ear barotrauma as a post-operative complication following robot-assisted radical prostatectomy (RARP). A 65-year-old man diagnosed with localised prostate carcinoma underwent elective RARP in a steep Trendelenburg position. Postoperatively, the patient complained of bothersome dizziness and spinning of surroundings associated with nausea. The patient was diagnosed to have vestibular symptoms secondary to inner ear barotrauma. He was started on prochlorperazine 12.5 mg and antibiotics, following which the patient improved. Vestibular rehabilitation exercises were taught to the patient. After 3 days of treatment, the patient did well with no episodes of dizziness. The patient was discharged on tablet cinnarizine 25 mg thrice daily for a week. On follow-up, the patient is asymptomatic. Inner ear barotrauma can be a rare complication of a combination of prolonged steep Trendelenburg during robotic surgery and pneumoperitoneum. Only further reporting of such incidents can help determine predisposing factors and precautions for preventing such incidents.

Effects of pneumoperitoneum and Trendelenburg position on intracranial pressure and cerebral blood flow assessed using transcranial doppler: A prospective observational study.

Background and Aims: Laparoscopic lower abdominal surgeries involve carbon dioxide (CO2) insufflation and Trendelenburg position. The raised intra-abdominal pressure can increase intracranial pressure (ICP) and alter cerebral blood flow. This study was conducted to determine the effect of pneumoperitoneum and Trendelenburg position on ICP and cerebral perfusion pressure (CPP) measured using transcranial Doppler (TCD). Material and Methods: A prospective observational study was conducted in 43 patients of either sex, aged between 18 and 60 years with American Society of Anesthesiologists physical status I and II, undergoing elective laparoscopic surgery in Trendelenburg position. After standard anesthesia induction, pneumoperitoneum was created to facilitate surgery, maintaining an intra-abdominal pressure of 10-15 mmHg and Trendelenburg position of 25°-30°. End-tidal carbon dioxide (EtCO2) was maintained between 30 and 35 mmHg. The ICP was assessed non-invasively using TCD-based diastolic flow velocities (FVd) and pulsatility index (PI) of middle cerebral artery. Data was represented as mean ± standard deviation and compared using paired t test. A P value of < 0.05 was considered significant. Results: Mean ICPPI at baseline was 14.02 ± 0.89 mmHg which increased to 14.54 ± 1.21 mmHg at pneumoperitoneum and Trendelenburg position (P = 0.005). Mean ICPFVd at baseline was 6.25 ± 2.47 mmHg which increased to 8.64 ± 3.79 mmHg at pneumoperitoneum and Trendelenburg position (P < 0.001). There was no statistically significant change in the CPP or mean arterial pressure values intraoperatively. Conclusions: Laparoscopic procedures with CO2 pneumoperitoneum in Trendelenburg position increase ICP as measured using TCD ultrasonography. The CPP was not significantly altered when EtCO2 was maintained in the range of 30-35 mmHg.

Effect of sevoflurane, propofol and propofol with dexmedetomidine as maintenance agent on intracranial pressure in the Trendelenburg position during laparoscopic surgeries.

Background and Aim: Pneumoperitoneum (PP) and the Trendelenburg position (TP) in laparoscopic surgeries are associated with rise in intracranial pressure (ICP). The optic nerve sheath diameter (ONSD) is a surrogate marker of ICP. The study aimed to evaluate the effect of sevoflurane, propofol and propofol with dexmedetomidine as maintenance agent on ICP in TP during laparoscopic surgeries. Material and Methods: A total of 120 American Society of Anesthesiologists (ASA) physical status I/II patients, aged 18-65 years were randomly allocated into three groups: sevoflurane as group S, propofol as group P, and propofol with dexmedetomidine as group PD. The intra-abdominal pressure (IAP) was kept in the range of 12-14 mmHg and TP varied between 15°- 45° angle. The primary objective was comparison of ICP and secondary objectives were IOP, intraoperative hemodynamic and postoperative recovery characteristics among groups. The ONSD and IOP were measured in both eyes 10 min after endotracheal intubation (T0), 5 min after CO2 insufflation (T1), 5 min after TP (T2) and 5 min after deflation of gas (T3). The data were analyzed by using the Statistical Package for Social Sciences version 23. Results: ONSD and IOP at T1 and T2 were significantly higher than T0 in all groups, but no significant difference was found among the intergroup groups. Significantly lower heart rate and mean blood pressure were observed in PD group at T1 and T2 compared to group S and group P. Conclusion: The rise in ICP was comparable among sevoflurane, propofol, and propofol-dexmedetomidine combination as a maintenance agent during laparoscopic surgeries in TP.

Recruitable alveolar collapse and overdistension during laparoscopic gynecological surgery and mechanical ventilation: a prospective clinical study.

BACKGROUND: Laparoscopic surgery in Trendelenburg position may impede mechanical ventilation (MV) due to positioning and high intra-abdominal pressure. We sought to identify the positive end-expiratory pressure (PEEP) levels necessary to counteract atelectasis formation ("Open-Lung-PEEP") and to provide an equal balance between overdistension and alveolar collapse ("Best-Compromise-PEEP"). METHODS: In 30 patients undergoing laparoscopic gynecological surgery, relative overdistension and alveolar collapse were assessed with electrical impedance tomography (EIT) during a decremental PEEP trial ranging from 20 to 4 cmH2O in supine position without capnoperitoneum and in Trendelenburg position with capnoperitoneum. RESULTS: In supine position, the median Open-Lung-PEEP was 12 (8-14) cmH2O with 8.7 (4.7-15.5)% of overdistension and 1.7 (0.4-2.2)% of collapse. Best-Compromise-PEEP was 8 (6.5-10) cmH2O with 4.2 (2.4-7.2)% of overdistension and 5.1 (3.9-6.5)% of collapse. In Trendelenburg position with capnoperitoneum, Open-Lung-PEEP was 18 (18-20) cmH 2 O (p < 0.0001 vs supine position) with 1.8 (0.5-3.9)% of overdistension and 0 (0-1.2)% of collapse and Best-Compromise-PEEP was 18 (16-20) cmH2O (p < 0.0001 vs supine position) with 1.5 (0.7-3.0)% of overdistension and 0.2 (0-2.7)% of collapse. Open-Lung-PEEP and Best-Compromise-PEEP were positively correlated with body mass index during MV in supine position but not in Trendelenburg position. CONCLUSION: The PEEP levels required for preventing alveolar collapse and for balancing collapse and overdistension in Trendelenburg position with capnoperitoneum were significantly higher than those required for achieving the same goals in supine position without capnoperitoneum. Even with high PEEP levels, alveolar overdistension was negligible during MV in Trendelenburg position with capnoperitoneum. TRIAL REGISTRATION: This study was prospectively registered at German Clinical Trials registry (DRKS00016974).

The effects of 5-degree, 10-degree and 20-degree reverse Trendelenburg positions on intraoperative bleeding and postoperative Edemea and ecchymosis around the eye in open rhinoplasty.

PURPOSE: In this study, we investigated the effect of reverse Trendelenburg position (RTP), with five, ten, and twenty degrees, on intraoperative bleeding and postoperative edema and ecchymosis around the eye in open rhinoplasty operations. MATERIALS AND METHODS: Ninety patients undergoing open rhinoplasty were divided into three groups, 5° angle RTP (Group 5; n = 30), 10° angle RTP (Group 10; n = 30), and 20° angle RTP (Group 20; n = 30). After 3 min of preoxygenation, anesthesia was induced with 3 mg.kg-1 propofol, 1 µg.kg-1 fentanyl, and 0.6 mg/kg rocuronium for muscle relaxation. Maintenance of anesthesia was provided with a minimum alveolar concentration of 1-1.5 with sevoflurane, 1:1 O2/N2O. Hemodynamic variables, intraoperational bleeding, postoperative 1st, 3rd and 7th days ecchymosis and edema around the eyes of the patients were compared between the groups. RESULTS: Edema changes on postoperative 1st, 3rd and 7th days and ecchymosis changes around the eyes on postoperative 1st and 3rd days in Group 20 were found significantly lower than Group 5 (p < 0.017). Besides, the change of ecchymosis on the postoperative 1st day was found significantly lower in Group 20 compared to Group 10 (p < 0.017). The amount of intraoperative bleeding and surgical field evaluation score were found to be significantly lower in Group 10 and Group 20 compared to Group 5 (p < 0.017). CONCLUSION: We concluded that in open rhinoplasty surgeries, 20° degree RTP reduces intraoperative blood loss and provides a more bloodless surgical field, as well as reducing edema and ecchymoses around the eyes in the postoperative period.

Effect of pressure-controlled ventilation-volume guaranteed mode combined with individualized positive end-expiratory pressure on respiratory mechanics, oxygenation and lung injury in patients undergoing laparoscopic surgery in Trendelenburg position.

The study aimed to investigate the efficacy of PCV-VG combined with individual PEEP during laparoscopic surgery in the Trendelenburg position. 120 patients were randomly divided into four groups: VF group (VCV plus 5cmH2O PEEP), PF group (PCV-VG plus 5cmH2O PEEP), VI group (VCV plus individual PEEP), and PI group (PCV-VG plus individual PEEP). Pmean, Ppeak, Cdyn, PaO2/FiO2, VD/VT, A-aDO2 and Qs/Qt were recorded at T1 (15 min after the induction of anesthesia), T2 (60 min after pneumoperitoneum), and T3 (5 min at the end of anesthesia). The CC16 and IL-6 were measured at T1 and T3. Our results showed that the Pmean was increased in VI and PI group, and the Ppeak was lower in PI group at T2. At T2 and T3, the Cdyn of PI group was higher than that in other groups, and PaO2/FiO2 was increased in PI group compared with VF and VI group. At T2 and T3, A-aDO2 of PI and PF group was reduced than that in other groups. The Qs/Qt was decreased in PI group compared with VF and VI group at T2 and T3. At T2, VD/VT in PI group was decreased than other groups. At T3, the concentration of CC16 in PI group was lower compared with other groups, and IL-6 level of PI group was decreased than that in VF and VI group. In conclusion, the patients who underwent laparoscopic surgery, PCV-VG combined with individual PEEP produced favorable lung mechanics and oxygenation, and thus reducing inflammatory response and lung injury.Clinical Trial registry: chictr.org. identifier: ChiCTR-2100044928.

A prospective observational study on changes in endo-tracheal tube cuff pressure and its correlation with airway pressures during various stages of robotic pelvic surgeries.

Background and Aims: Robotic surgeries often require a relatively long duration of pneumo-peritoneum and trendelenburg position which may accentuate changes in endo-tracheal tube (ETT) cuff pressure leading to pressure related complications. The aim of this study was to analyze changes in ETT cuff pressures during various stages of pneumo-peritoneum and surgical positioning and its correlation with airway pressure changes. Material and Methods: A prospective observational study was planned after approval of institutional review board on 60 patients undergoing elective robotic pelvic surgery requiring head down position. Baseline cuff pressure was adjusted to 25 cm H2O. ETT cuff pressure, peak airway pressure and end tidal CO2 (ETCO2) was measured at various time intervals before and after pneumo-peritoneum and head down. Ventilatory parameters were kept fixed after baseline setting. Those requiring any change were excluded. Pearson's coefficient was used for correlation and ANOVA for trend of parameters at different time intervals (P value <0.05 was considered significant). Results: Baseline cuff pressure after manual inflation was 46.2 ± 17.4 cm H2O. Significant correlation was observed between change in cuff pressure and increase in peak airway pressure at the end of the surgery (r = 0.4, P < 0.05). Serial measurements of ETT cuff pressure, peak airway pressure and ETCO2 were significantly increased compared to baseline (P < 0.05). Conclusion: Significant increases in ETT cuff pressure may be seen in robotic surgeries, with a positive correlation between change in cuff pressure and increase in airway pressures. Objective adjusted measurement of cuff pressure and airway pressures is recommended for such surgeries.

Umbilical cord prolapse: revisiting its definition and management.

Umbilical cord prolapse is an unpredictable obstetrical emergency with an incidence ranging from 1 to 6 per 1000 pregnancies. It is associated with high perinatal mortality, ranging from 23% to 27% in low-income countries to 6% to 10% in high-income countries. In this review, we specifically addressed 3 issues. First, its definition is not consistent in the current literature, and "occult cord prolapse" is a misnomer because the cord is still above the cervix. We proposed that cord prolapse, cord presentation, and compound cord presentation should be classified according to the positional relationship among the cord, the fetal presenting part, and the cervix. All of them may occur with either ruptured or intact membranes. The fetal risk is highest in cord prolapse, followed by cord presentation, and lastly by compound cord presentation, which replaces the misnomer "occult cord prolapse." Second, the mainstay of treatment of cord prolapse is urgent delivery, which means cesarean delivery in most cases, unless vaginal delivery is imminent. The urgency depends on the fetal heart rate pattern, which can be bradycardia, recurrent decelerations, or normal. It is most urgent in cases with bradycardia, because a recent study showed that cord arterial pH declines significantly with the bradycardia-to-delivery interval at a rate of 0.009 per minute (95% confident interval, 0.0003-0.0180), and this may indicate an irreversible pathology such as vasospasm or persistent cord compression. However, cord arterial pH does not correlate with either deceleration-to-delivery interval or decision-to-delivery interval, indicating that intermittent cord compression causing decelerations is reversible and less risk. Third, while cesarean delivery is being arranged, different maneuvers should be adopted to relieve cord compression by elevating the fetal presenting part and to prevent further cord prolapse beyond the vagina. A recent study showed that the knee-chest position provides the greatest elevation effect, followed by filling of the maternal urinary bladder with 500 mL of fluid, and then the Trendelenburg position (15°) and other maneuvers. However, each maneuver has its own advantages and limitations; thus, they should be applied wisely and with great caution, depending on the actual clinical situation. Therefore, we have proposed an algorithm to guide this acute management.

Transperineal ultrasound assessment of fetal head elevation by maneuvers used for managing umbilical cord prolapse.

OBJECTIVE: To assess objectively the degree of fetal head elevation achieved by different maneuvers commonly used for managing umbilical cord prolapse. METHODS: This was a prospective observational study of pregnant women at term before elective Cesarean delivery. A baseline assessment of fetal head station was performed with the woman in the supine position, using transperineal ultrasound for measuring the parasagittal angle of progression (psAOP), head-symphysis distance (HSD) and head-perineum distance (HPD). The ultrasonographic measurements of fetal head station were repeated during different maneuvers, including elevation of the maternal buttocks using a wedge, knee-chest position, Trendelenburg position with a 15° tilt and filling the maternal urinary bladder with 100 mL, 300 mL and 500 mL of normal saline. The measurements obtained during the maneuvers were compared with the baseline measurements. RESULTS: Twenty pregnant women scheduled for elective Cesarean section at term were included in the study. When compared with baseline (median psAOP, 103.6°), the knee-chest position gave the strongest elevation effect, with the greatest reduction in psAOP (psAOP, 80.7°; P < 0.001), followed by filling the bladder with 500 mL (psAOP, 89.9°; P < 0.001) and 300 mL (psAOP, 94.4°; P < 0.001) of normal saline. Filling the maternal bladder with 100 mL of normal saline (psAOP, 96.1°; P = 0.001), the Trendelenburg position (psAOP, 96.8°; P = 0.014) and elevating the maternal buttocks (psAOP, 98.3°; P = 0.033) gave modest elevation effects. Similar findings were reported for HSD and HPD. The fetal head elevation effects of the knee-chest position, Trendelenburg position and elevation of the maternal buttocks were independent of the initial fetal head station, but that of bladder filling was greater when the initial head station was low. CONCLUSIONS: To elevate the fetal presenting part, the knee-chest position provides the best effect, followed by filling the maternal urinary bladder with 500 mL then 300 mL of fluid, respectively. Filling the bladder with 100 mL of fluid, the Trendelenburg position and elevation of the maternal buttocks have modest effects. © 2020 International Society of Ultrasound in Obstetrics and Gynecology.