Laparoscopic Abdominal Surgery Research Articles

Recruitment Maneuver to Reduce Postoperative Pulmonary Complications after Laparoscopic Abdominal Surgery: A Systematic Review and Meta-Analysis.

Background: Lung-protective ventilation strategies are recommended for patients undergoing mechanical ventilation. However, there are currently no guidelines to follow regarding recruitment maneuvers (RMs). We attempted to identify the effects of RMs on patients undergoing laparoscopic abdominal surgery. Methods: We searched for randomized controlled trials (RCTs) in PubMed, the Cochrane Library databases, Embase, Web of Science and the ClinicalTrials.gov registry for trials published up to December 2021. The primary outcome was postoperative pulmonary complications (PPCs). The secondary outcomes consisted of the static lung compliance, driving pressure (DP), intraoperative oxygenation index (OI), OI in the post-anesthesia care unit (PACU), mean arterial pressure (MAP) and heart rate (HR). Seventeen RCTs with a total of 3480 patients were examined. Results: Patients who received RMs showed a considerable reduction in PPCs (risk ratio (RR) = 0.70; 95% confidence interval (CI): 0.62 to 0.79; p < 0.01), lower DP (weighted mean difference (WMD) = −3.96; 95% CI: −5.97 to −1.95; p < 0.01), elevated static lung compliance (WMD = 10.42; 95% CI: 6.13 to 14.71; p < 0.01) and improved OI (intraoperative: WMD = 53.54; 95% CI: 21.77 to 85.31; p < 0.01; PACU: WMD = 59.40; 95% CI: 39.10 to 79.69; p < 0.01) without substantial changes in MAP (WMD = −0.16; 95% CI −1.35 to 1.03; p > 0.05) and HR (WMD = −1.10; 95% CI: −2.29 to 0.10; p > 0.05). Conclusions: Recruitment maneuvers reduce postoperative pulmonary complications and improve respiratory mechanics and oxygenation in patients undergoing laparoscopic abdominal surgery. More data are needed to elucidate the effect of recruitment maneuver on the circulatory system.

Correlation of arterial PaCO2 to end tidal CO2 in children undergoing laparoscopic abdominal surgery: An observational study.

The reliability of end tidal carbon dioxide (ETCO2) as a measure of arterial carbon dioxide (PaCO2) in pediatric laparoscopy is unclear. We evaluated the correlation of arterial to end tidal P(a-ET) CO2 during pediatric laparoscopy at two hours of pneumoperitoneum as the primary objective. We also compared P(a-ET) CO2 and alveolar to arterial oxygen gradient P(A-a) O2 and haemodynamics at fixed time points during surgery. A cross-sectional study was conducted in 25 children undergoing laparoscopic abdominal surgery. Arterial blood gases were drawn at T0, baseline, T10: ten minutes, T1h: 1 hour, T2h: 2 hours of pnuemoperitoneum and T 10d: 10 mins after deflation. The P(a-ET) CO2, P(A-a) O2, were measured from the blood gas and ETCO2 and FiO2 values on the monitor. The Pearson's correlation coefficient, the Wilcoxon rank test and Chi square test were used for statistical analysis. At T2h moderate correlation of P(a-ET) CO2 (r = 0.605, P = 0.001) with 40% children documenting accurate P(a-ET) CO2, -1 to +1 mm Hg was seen. Moderate correlation was also seen at T0, T10, T 10d but poor correlation at T 1h. The P(A-a) O2 increased progressively with surgery and did not correlate with P(a-ET) CO2. Heart rate was stable, but systolic blood pressures at T 10 and diastolic at T10, T 1h, T 2h were higher than baseline. Moderate correlation was seen between PaCO2 and ETCO2 at 2 h of pnuemoperitoneum and at T0, T 10, and T 10d. P(A-a) O2 increased with surgery but did not correlate with P(a-ET) CO2.

Impact of AirSeal® insufflation system on respiratory and circulatory dynamics during laparoscopic abdominal surgery.

The effect of the AirSeal® insufflation system on hemodynamic parameters, especially end-tidal carbon dioxide (EtCO2), during laparoscopic abdominal surgery remains unclear. This retrospective single-center study included 333 consecutive patients who underwent laparoscopic hepatectomy (n = 43), gastrectomy (n = 69), colectomy (n = 137), or proctectomy (n = 84) using the AirSeal®. Patient demographics and intraoperative hemodynamic parameters, such as EtCO2, peripheral capillary oxygen saturation (SpO2), and arterial systolic blood pressure (ABP), were collected and analyzed. EtCO2 was evaluated during the entire operative period (whole period) as well as the pneumoperitoneum period until specimen removal (pneumoperitoneum period). We defined “positive respiratory and circulatory responses” (positive responses) as a decrease in EtCO2 ≥ 3 mmHg in addition to decreases in SpO2 ≥ 3% and ABP ≥ 10 mmHg simultaneously, which suggest possible carbon dioxide (CO2) embolism. The median EtCO2 values of hepatectomy, gastrectomy, colectomy, and proctectomy in the whole period/pneumoperitoneum period were 37.3/37.4, 37.1/37.3, 37.4/37.9, and 38.2/38.4 mmHg, respectively. The EtCO2 of proctectomy was significantly higher than that of gastrectomy during the whole and pneumoperitoneum periods (P < 0.05). In contrast, the EtCO2 of hepatectomy was comparable to that of the other three surgeries in the whole and pneumoperitoneum periods. Meanwhile, nine (2.7%; eight hepatectomies and one proctectomy) patients showed positive responses, and one who underwent a partial hepatectomy developed a clinically manifested CO2 embolism. Positive responses occurred during venous exposure or bleeding in all nine cases. Although the EtCO2 of hepatectomy was comparable to that of the other surgeries using the AirSeal®, laparoscopic hepatectomy showed a tendency of CO2 embolism. Thus, a secure and careful surgical approach is mandatory for laparoscopic hepatectomy using the AirSeal® insufflation system.

Comparison of Single-Dermatome Laparoscopic Appendectomy With Standard Laparoscopic Appendectomy in Terms of Postoperative Pain and Patient Satisfaction: A Randomized Controlled Trial.

Laparoscopic appendectomy (LA), used since 1980, is a common surgical technique for acute appendicitis (AA) treatment. Laparoscopic surgical techniques can achieve higher patient satisfaction than conventional open surgery techniques. However, many patients complain of severe pain after laparoscopic abdominal surgeries. In this study, we compared single-dermatome laparoscopic appendectomy (SDLA), wherein all trocars were placed at the same dermatome field, with standard laparoscopic appendectomy (SLA), wherein trocars were placed at multiple dermatome sites, in terms of postoperative pain and patient satisfaction. The study was designed as a double-blind randomized controlled trial. Patients who underwent LA for AA between May 2019 and December 2019 were included in the study and randomized into 2 groups, wherein patients were included sequentially. The first group was operated with SLA surgery, whereas the second group was operated with SDLA surgery. All patients were assessed in terms of visual analog scale (VAS) scores, hemodynamic parameters, and patient satisfaction at postoperative 1, 2, 4, 6, 12, and 24 hours. In the SLA technique, VAS values at postoperative 1, 2, and 4 hours were significantly higher than in the SDLA ( P =0.009; P <0.05). No significant difference was observed between the surgical techniques in terms of VAS levels at postoperative 6, 12, and 24 hours ( P >0.05). In the SDLA group, patient satisfaction was significantly higher than in the SLA group ( P =0.024; P <0.05). In our study, SDLA caused less pain in AA cases during postoperative period than SLA. Further, the SDLA method achieved higher patient satisfaction during the postoperative period than the SLA method.

Do the Fluids Consumed by Surgical Patients in the Postoperative Period Affect Their Gastrointestinal Motility? A Correlational Study

The aim of this study was to determine the relationship between gastrointestinal (GI) motility and oral fluid intake levels in the postoperative period. This descriptive and correlational study was performed in an education and research hospital between June and September 2019. The sample in this study consisted of individuals aged 18 to 80 years who had undergone laparoscopic abdominal surgery. No sampling was performed, and all patients volunteering to take part were included. Patients were started on oral nutrition in a median of 6 hours (min: 6 max: 8) after surgery and received 500.00 mL (min: 100 max: 500) oral fluid on the first day after surgery, 600.00 mL (min: 200 max: 1200) on the second, and 725.00 mL (min: 652.47 max: 759.52) on the third. Median time to passage of flatus was 22.50 hours (min: 6 max: 36), and median time to stool production was 39.00 hours (min: 16 max: 70). A positive correlation was found between the amount of oral fluid consumption on the first day and time to passage of flatus, while a negative correlation was observed between the amount of fluid consumption on the second day and time to both flatus and stool production. Time to flatus production increased in line with the amount of fluid consumed via the oral route on the first day postoperatively, while times to production of flatus and stool decreased as the amount of fluid consumed orally on the second day increased.

The Neuroimmune Response to Surgery - An Exploratory Study of Trauma-Induced Changes in Innate Immunity and Heart Rate Variability.

Surgery triggers a systemic inflammatory response that ultimately impacts the brain and associates with long-term cognitive impairment. Adequate regulation of this immune surge is pivotal for a successful surgical recovery. We explored the temporal immune response in a surgical cohort and its associations with neuroimmune regulatory pathways and cognition, in keeping with the growing body of evidence pointing towards the brain as a regulator of peripheral inflammation. Brain-to-immune communication acts through cellular, humoral and neural pathways. In this context, the vagal nerve and the cholinergic anti-inflammatory pathway (CAP) have been shown to modify peripheral immune cell activity in both acute and chronic inflammatory conditions. However, the relevance of neuroimmune regulatory mechanisms following a surgical trauma is not yet elucidated. Twenty-five male patients undergoing elective laparoscopic abdominal surgery were included in this observational prospective study. Serial blood samples with extensive immune characterization, assessments of heart rate variability (HRV) and cognitive tests were performed before surgery and continuing up to 6 months post-surgery. Temporal immune responses revealed biphasic reaction patterns with most pronounced changes at 5 hours after skin incision and 14 days following surgery. Estimations of cardiac vagal nerve activity through HRV recordings revealed great individual variations depending on the pre-operative HRV baseline. A principal component analysis displayed distinct differences in systemic inflammatory biomarker trajectories primarily based on pre-operative HRV, with potiential consequences for long-term surgical outcomes. In conclusion, individual pre-operative HRV generates differential response patterns that associate with distinct inflammatory trajectories following surgery. Long-term surgical outcomes need to be examined further in larger studies with mixed gender cohorts.

Robotic vaginal natural orifice transluminal endoscopic myomectomy

Robotic vaginal natural orifice transluminal endoscopic myomectomy

Prediction of blood pressure changes associated with abdominal pressure changes during robotic laparoscopic low abdominal surgery using deep learning.

BackgroundIntraoperative hypertension and blood pressure (BP) fluctuation are known to be associated with negative patient outcomes. During robotic lower abdominal surgery, the patient’s abdominal cavity is filled with CO2, and the patient’s head is steeply positioned toward the floor (Trendelenburg position). Pneumoperitoneum and the Trendelenburg position together with physiological alterations during anesthesia, interfere with predicting BP changes. Recently, deep learning using recurrent neural networks (RNN) was shown to be effective in predicting intraoperative BP. A model for predicting BP rise was designed using RNN under special scenarios during robotic laparoscopic surgery and its accuracy was tested.MethodsDatabases that included adult patients (over 19 years old) undergoing low abdominal da Vinci robotic surgery (ovarian cystectomy, hysterectomy, myomectomy, prostatectomy, and salpingo-oophorectomy) at Soonchunhyang University Bucheon Hospital from October 2018 to March 2021 were used. An RNN-based model was designed using Python3 language with the PyTorch packages. The model was trained to predict whether hypertension (20% increase in the mean BP from baseline) would develop within 10 minutes after pneumoperitoneum.ResultsEight distinct datasets were generated and the predictive power was compared. The macro-average F1 scores of the datasets ranged from 68.18% to 72.33%. It took only 3.472 milliseconds to obtain 39 prediction outputs.ConclusionsA prediction model using the RNN may predict BP rises during robotic laparoscopic surgery.

Quadrant and Dermatomal Analysis of Sensorial Block in Ultrasound- Guided Erector Spinae Plane Block.

As a novel procedure now gaining popularity, erector spinae plane block has been the subject of many studies. However, dermatomal coverage of the sensory block caused by erector spinae plane block has been rarely studied. The goal of this study is to evaluate the sensory block resulting from erector spinae plane block applied at the T9 vertebral level. This observational, prospective, blinded study was conducted on 50 adult patients undergoing laparoscopic abdominal surgery. All patients underwent bilateral erector spinae plane block at the T9 level after completion of the surgery while under general anesthesia. In order to further evaluate the sensory blockade, we divided the hemiabdomen-hemithorax region into 4 quadrants: dorsal-medial, dorsal- laterel, ventral-lateral, and ventral-medial. The sensorial evaluation was performed using the pinprick test, 2 hours following the application of erector spinae plane block. A total of 28 female and 22 male patients were examined in this study. Complete failure of the block was recorded in 7 patients, with no thoracic/lumbar segmental or quadrant involvement. Successful sensory block was achieved in 67% of the dorsolateral quadrants, 58% of the dorsomedial quadrants, 69% of the ventrolateral quadrants, and 55% of the ventromedial quadrants. Cutaneous sensory block of erector spinae plane block at T9 vertebral level revealed variable results and low failure rates. Administration of erector spinae plane block for postoperative analgesia in thoracoab- dominal surgeries requires further randomized controlled trials to confirm its effectiveness and convenience.

Comparative evaluation of the hemodynamic effects of inclusion versus exclusion of dexmedetomidine to pregabalin and fentanyl premedication regimen during airway instrumentation in laparoscopic abdominal surgeries

Background: Airway instrumentation leads to an aggravated hemodynamic response due to increased sympathetic activity, imposing a risk of myocardial ischemia. A premedication regimen using fentanyl and pregabalin blunts the pressure response but not the rate response. Objective: To compare the effects of pregabalin and fentanyl regimen versus pregabalin, fentanyl, and dexmedetomidine regimen on the hemodynamic pressor response during airway instrumentation in laparoscopic abdominal surgery (LAS). Methods: Sixty patients (ASA I and II), undergoing elective LASunder general anesthesia, were randomly divided into 2 groups - Group A (n=30) premedicated with oral pregabalin (150mg) and IV fentanyl (2μg/kg) and Group B (n=30) premedicated with IV dexmedetomidine (0.25μg/kg) in addition to pregabalin-fentanyl regimen. Both groups were managed with the same anesthetic protocol. The preoperative sedation level was assessed before induction. The heart rate (HR), systolic and diastolic BP (SBP, DBP), and mean arterial pressure (MAP) were recorded at baseline as well as preoperatively, prior to intubation and at 1, 3, 5, 10, and 15 min after intubation. Results: Both groups had similar distribution of age, weight, gender, physical status, sedation level as well as intra-operative fentanyl and postoperative analgesic requirements.

Surgical Outcome in Laparoscopic Abdominal Surgical Operations with Clostridium Difficile Infection.

Introduction: Postoperative Clostridium difficile infection (CDI) has associated morbidity, but it is unknown how it impacts different operations. We sought to determine the incidence and postoperative morbidity following abdominal surgery.Method: The National Surgical Quality Improvement Program database (2015-2019) was utilized to evaluate adult (≥18 years-old) patients who developed CDI following laparoscopic abdominal operations. Univariate and multivariate analysis were performed to evaluate outcomes.Results: A total of 973338 patients were studied and the overall incidence of CDI was .3% within 30 days of operation. Colorectal surgery had the highest incidence of CDI (1601/167949,1.0%) with significantly longer mean length of stay (LOS) (8.0 days± 9.0, P < .01) compared to other surgical procedures. CDI patients also had a longer mean length of stay (6.6± 8.0 vs 2.1 ± 3.6 days, P < .01) and increased mortality (1.8% vs .2%, AOR: 4.64, CI: 3.45-5.67, P < .01) compared to patients without CDI.Conclusions: This national analysis demonstrates that CDI is a significant complication following abdominal surgery and is associated with increased LOS and mortality. Furthermore, laparoscopic colorectal surgery appears to have the greatest risk of CDI. Future research is needed to determine the exact cause in order to decrease the incidence of CDI by reconsidering the protocol of antibiotic use within the high-risk population.

Toward Incorporating Health-Related Quality of Life as Coprimary End Points in Clinical Trials: Time to Achieve Clinical Important Differences and QoL Profiles.

Besides morbidity and mortality, quality of life (QoL) is a key outcome of cancer treatments. Trials on the basis of clinical outcomes have expectations that QoL outcomes can be either tolerated or improved. Simultaneously considering QoL and clinical outcomes is challenging with lack of suitable metrics allowing incorporation of QoL as coprimary end points in clinical trial design and utilization of hierarchical hypothesis testing. We propose combining time to achieving a minimal clinically important difference (MCID) and probabilities of a MCID occurring in each QoL domain to provide QoL metrics analogous to those used for clinical end points. For QoL domains of interest, these yield QoL profiles, time to MCID, and number needed to treat. Incorporation of QoL as coprimary end points in clinical trial designs through hierarchical hypothesis testing can easily be achieved. The noninferiority designed Laparoscopic Approach to Carcinoma of the Endometrium trial, evaluating laparoscopic versus open abdominal surgery for endometrial cancer with Functional Assessment of Cancer Therapy-General QoL domains, is used to illustrate the usefulness of these metrics. This analysis revealed that laparoscopic surgery had a significant shorter time to MCID for physical and functional well-being QoL domains (physical mean: 1.5 months, 95% CI, 0.5 to 2.6; P = .002; and functional mean: 1.4 months; 95% CI, 0.4 to 2.4; P = .003) than abdominal surgery, but little difference between the two approaches for psychologic social and emotion well-being. Probability profile plots show a consistent > 2-fold higher chance of attaining a MCID for physical and functional well-being over time for laparoscopic compared with abdominal surgery. This analysis reinforces the potential value of novel MCID metrics and their usefulness in raising the profile of QoL outcomes to complement clinical end points. The methods will allow health professionals to counsel patients about QoL outcomes and clinical outcomes simultaneously.

Novel temperature-responsive hydrogel injected to the incision site for postoperative pain relief in laparoscopic abdominal surgery: a single-blind, randomized, pivotal clinical trial.

A temperature-responsive hydrogel (PF-72; TGel Bio, Inc., Ltd, Seoul, Korea), developed as a sustained drug delivery device, can be mixed with ropivacaine to reduce pain in the incision area. The hydrogel is soluble at low temperatures (2-8°C) and is converted into a gel at high temperatures (> 30°C). We aimed to evaluate whether the administration of ropivacaine using PF-72 at incision sites reduces pain until 72h postoperatively in patients undergoing laparoscopic stomach or colorectal surgery. Patients were randomly assigned to the control group (0.75% ropivacaine) or PF-72 group (PF-72 mixed with 0.75% ropivacaine). Before surgical incision closure, 0.75% ropivacaine or PF-72 mixed with 0.75% ropivacaine was injected into the subcutaneous fat and muscle of all incisions. Postoperative pain was evaluated by the Numerical Rating Scale (NRS, 0 = no pain, 10 = most severe pain) for wound pain at 3, 6, 24, 48, and 72h after the end of surgery. Ninety-nine patients (control, n = 51; PF-72, n = 48) were included in the analysis. The areas under the curve of NRS for wound pain until 72h in the control group and the PF-72 group were 188.7 ± 46.1 and 135.3 ± 49.9h, respectively (P < 0.001). The frequency of the administration of rescue analgesics in the general ward was similar between the two groups. PF-72 mixed with 0.75% ropivacaine reduced postoperative pain until 72h in patients undergoing laparoscopic surgery. Although the study population was not large enough for safety evaluation, no adverse events associated with PF-72 were observed.

Goal-Directed Fluid Therapy Enhances Gastrointestinal Recovery after Laparoscopic Surgery: A Systematic Review and Meta-Analysis.

(1) Background: Whether goal-directed fluid therapy (GDFT) provides any outcome benefit as compared to non-goal-directed fluid therapy (N-GDFT) in elective abdominal laparoscopic surgery has not been determined yet. (2) Methods: A systematic literature search was conducted in MEDLINE, Embase, CENTRAL, Web of Science, and Scopus. The main outcomes were length of hospital stay (LOHS), time to first flatus and stool, intraoperative fluid and vasopressor requirements, serum lactate levels, and urinary output. Pooled risks ratios (RRs) with 95% confidence intervals (CI) were calculated for dichotomous outcomes and weighted mean difference (WMD) with 95% CI for continuous outcomes. (3) Results: Eleven studies were included in the quantitative, and fifteen in the qualitative synthesis. LOHS (WMD: −1.18 days, 95% CI: −1.84 to −0.53) and time to first stool (WMD: −9.8 h; CI −12.7 to −7.0) were significantly shorter in the GDFT group. GDFT resulted in significantly less intraoperative fluid administration (WMD: −441 mL, 95% CI: −790 to −92) and lower lactate levels at the end of the operation: WMD: −0.25 mmol L−1; 95% CI: −0.36 to −0.14. (4) Conclusions: GDFT resulted in enhanced recovery of the gastrointestinal function and shorter LOHS as compared to N-GDFT.

Evaluation of contrast-enhanced ultrasonography with Sonazoid® in visualization of local anesthetic distribution in rectus sheath block: a prospective, clinical study.

Clear visualization of ultrasound (US) images is crucial for successful US-guided nerve block. However, accurate determination of local anesthetic (LA) distribution from US images remains difficult. Sonazoid®, which comprises perflubutane microbubbles, is used to diagnose hepatic and breast tumors. This study aimed to investigate the visibility of Sonazoid® in perioperative US-guided nerve block. We performed rectus sheath block (RSB) in patients scheduled for laparoscopic abdominal surgery (n = 10). 10mL of a mixture containing equal amounts of 0.75% ropivacaine and iohexol with the addition of Sonazoid® diluted 100-fold was administered. We investigated the correlation and agreement between Sonazoid® and iohexol distributions. The brightness of the solution and tissues was calculated: a grayscale value between 0 (dark) and 255 (bright) was measured in all pixels of the region of interest. Adverse events were also investigated. Sonazoid® was clearly visualized and distinguished from the surrounding tissues both during and after RSB. The spread of Sonazoid® and iohexol was significantly correlated (spearman's ρ = 0.53, p = 0.0004). Bland-Altman analyses revealed significant mean difference between two methods (15.6mm; 95% confidence interval [CI]: 10.6, 20.6; standard deviation (SD) 15.65; p < 0.0001). Limits of agreement were -14.94 to 46.24mm. Sonazoid® significantly increased the mean grayscale values at the posterior rectus sheath (93.7 vs. 201.9, p < 0.0001). There were no complications. Sonazoid diluted 100-fold® was clearly visualized real-time, and the enhancement was sustained and measurable after RSB. Sonazoid® could potentially be used for the contrast agent of US-guided nerve block.

Gastrointestinal outcomes following transversus abdominus plane blocks in laparoscopic colorectal surgery: a systematic review

Background: Significant data exists to support the use of transversus abdominus plane (TAP) blocks to reduce post-operative pain and opiate consumption following laparoscopic abdominal surgery, although whether this reduced usage corresponds to a reduction in the development of ileus is not known.

Lateral Quadratus Lumborum Block versus Transversus Abdominis Plane Block in Laparoscopic Surgery: A Randomized Controlled Study.

Background After laparoscopic abdominal surgery, we aim to evaluate the analgesic efficiency of US-directed bilateral transversus abdominis plane block (TAPB) and quadratus lumborum block (QLB). Methods 50 patients aged 18–60 years listed for elective laparoscopic abdomen operation were registered in this study. Cases were randomly allocated into two similar groups: TAPB and QLB groups. The first outcome was the growing morphine consumption on the 1st day postoperatively. The second outcome involved VAS score, first analgesic necessities, and any postoperative complications. Statistical analysis was done with the 2-sample t-test, and Mann–Whitney U testing was utilized to compare medians for skewed end points. Qualitative data were introduced as numbers and percentages, and chi-squared testing was utilized to determine the significance. Results The median cumulative morphine consumptions on the 1st day were high significantly in the TAPB group than in the QLB group (6 mg [6, 9] vs. 3 mg [3, 6], p value ≤0.0001]). The QLB group showed an increase in the median of the time to the first analgesic request in comparison with the TAPB group (17 hours [12, 24] vs. 8 hours [6, 24], p ≤ 0.001). In addition, on the 1st day, the mean VAS scoring at rest was lower in the QLB group. Conclusion In comparison to the TAPB, the QL block delivers more successful pain relief, has an extended period of analgesic actions, extends interval to the 1st analgesic necessity, is accompanied with lesser morphine consumptions, and may be utilized in multimodal analgesia and opioid-sparing regimens after that laparoscopic operation. This trial is registered with NCT04553991.

Gases for establishing pneumoperitoneum during laparoscopic abdominal surgery.

This is the second update of a Cochrane Review first published in 2013 and last updated in 2017. Laparoscopic surgery is now widely performed to treat various abdominal diseases. Currently, carbon dioxide is the most frequently used gas for insufflation of the abdominal cavity (pneumoperitoneum). Although carbon dioxide meets most of the requirements for pneumoperitoneum, the absorption of carbon dioxide may be associated with adverse events. Therefore, other gases have been introduced as alternatives to carbon dioxide for establishing pneumoperitoneum. To assess the safety, benefits, and harms of different gases (e.g. carbon dioxide, helium, argon, nitrogen, nitrous oxide, and room air) used for establishing pneumoperitoneum in participants undergoing laparoscopic abdominal or gynaecological pelvic surgery. We searched CENTRAL, Ovid MEDLINE, Ovid Embase, four other databases, and three trials registers on 15 October 2021 together with reference checking, citation searching, and contact with study authors to identify additional studies. We included randomised controlled trials (RCTs) comparing different gases for establishing pneumoperitoneum in participants (irrespective of age, sex, or race) undergoing laparoscopic abdominal or gynaecological pelvic surgery under general anaesthesia. We used standard methodological procedures expected by Cochrane. We included 10 RCTs, randomising 583 participants, comparing different gases for establishing pneumoperitoneum: nitrous oxide (four trials), helium (five trials), or room air (one trial) was compared to carbon dioxide. All the RCTs were single-centre studies. Four RCTs were conducted in the USA; two in Australia; one in China; one in Finland; one in Iran; and one in the Netherlands. The mean age of the participants ranged from 27.6 years to 49.0 years. Four trials randomised participants to nitrous oxide pneumoperitoneum (132 participants) or carbon dioxide pneumoperitoneum (128 participants). None of the trials was at low risk of bias. The evidence is very uncertain about the effects of nitrous oxide pneumoperitoneum compared to carbon dioxide pneumoperitoneum on cardiopulmonary complications (Peto odds ratio (OR) 2.62, 95% CI 0.78 to 8.85; 3 studies, 204 participants; very low-certainty evidence), or surgical morbidity (Peto OR 1.01, 95% CI 0.14 to 7.31; 3 studies, 207 participants; very low-certainty evidence). There were no serious adverse events related to either nitrous oxide or carbon dioxide pneumoperitoneum (4 studies, 260 participants; very low-certainty evidence). Four trials randomised participants to helium pneumoperitoneum (69 participants) or carbon dioxide pneumoperitoneum (75 participants) and one trial involving 33 participants did not state the number of participants in each group. None of the trials was at low risk of bias. The evidence is very uncertain about the effects of helium pneumoperitoneum compared to carbon dioxide pneumoperitoneum on cardiopulmonary complications (Peto OR 1.66, 95% CI 0.28 to 9.72; 3 studies, 128 participants; very low-certainty evidence), or surgical morbidity (5 studies, 177 participants; very low-certainty evidence). There were three serious adverse events (subcutaneous emphysema) related to helium pneumoperitoneum (3 studies, 128 participants; very low-certainty evidence). One trial randomised participants to room air pneumoperitoneum (70 participants) or carbon dioxide pneumoperitoneum (76 participants). The trial was at high risk of bias. There were no cardiopulmonary complications, serious adverse events, or deaths observed related to either room air or carbon dioxide pneumoperitoneum. AUTHORS' CONCLUSIONS: The evidence is very uncertain about the effects of nitrous oxide, helium, and room air pneumoperitoneum compared to carbon dioxide pneumoperitoneum on any of the primary outcomes, including cardiopulmonary complications, surgical morbidity, and serious adverse events. The safety of nitrous oxide, helium, and room air pneumoperitoneum has yet to be established, especially in people with high anaesthetic risk.

Evaluation of the learning curve and safety outcomes in robotic assisted vaginal natural orifice transluminal endoscopic hysterectomy: A case series of 84 patients.

To explore the learning curve and safety outcomes of robotic assisted transvaginal natural orifice transluminal endoscopic surgery (R-vNOTES) for hysterectomy in benign gynaecological diseases. A retrospective chart review of all patients undergoing R-vNOTES hysterectomy for benign gynaecological disease from 2019 to 2021. An academic tertiary care university hospital in Houston, TX, USA. 84 patients were identified that met the study requirements. The mean hysterectomy time was 77.27±2.89min. The median additional operation time was 63 (8-206)min. There were two conversions to robotic assisted single incision laparoscopy. Thirteen (15.48%) patients had an associated complication. Analysis of the learning curve suggests plateauing of hysterectomy time at approximately 10 cases and time for robot docking and port placement after 10-20 cases. R-vNOTES is a safe and effective route for hysterectomy. For a surgeon with experience in laparoscopic single site surgery and abdominal robotic surgery, they need to perform 10 cases of R-vNOTES hysterectomy and 10-20 cases in port placement and robotic docking to achieve proficiency.

Abstract No.: ABS1045: Ultrasonographic evaluation of the effect of positive end expiratory pressure andpulmonary recruitment maneuver on diaphragmatic functions in patients undergoing laparoscopic abdominal surgery

Background & Aims:Reports suggest diaphragmatic impairment after laparoscopic abdominal surgery by gas insufflation causes postoperativepulmonary dysfunction. Intraoperative PEEP, recruitment maneuver prevents lung atelectasis mitigating complications.The aim was to evaluate effects of PEEP,pulmonary recruitment maneuver on diaphragmatic functions during pneumoperitoneum in patients undergoing laparoscopic surgeriesMethods:After ethical committee clearance and patient consent, a randomised control trial conducted among 63 patients undergoing laparoscopic abdominal surgeries under GA. Patient belonging to ASA 1,2 and giving informed written consent were includedthose having severe systemic illness, BMI>30 were excluded. Patients undergoing laparoscopic abdominal surgery under GAwere randomized using computer generated numbers into three equal groups, A with zero PEEP, B with 5 PEEP, C withpulmonary recruitment maneuver. Perioperatively diaphragmatic excursion, intraoperatively peak inspiratory pressure, hemodynamic parameters (MAP, HR) and dynamic compliance of the lungs were measured. Mann Whitney U test were applied.Results:Mean diaphragmatic excursion in cm at baseline, after pneumoperitoneum, reverse Trendelenburg position, extubation, 6 h postoperatively in Group A (3.63+0.28,.040+18,3.08+0.008,2.88+0.34,3.56+0.33,) Group B (3.65+0.27,3.29+0.30,3.13+0.29,3.40+0.37,3.65+0.29), Group C (3.75+0.31,3.41+0.28,3.20+0.30,3.40+0.34,3.74+0.31), p value (0.743,0.742,0.000,0.000.0.000), Mean Peak inspiratory pressure in mmhg before and after applying PEEP, after pneumoperitoneum and reverse Trendelenburg in Group A (16.11+0.90,16.04+0.89,22.01+1.20,22.06+1.27) Group B (16.19+1.03,16.73+2.74,22.44+1.39,23.98+2.28), Group C (16.21+1.05,16.73+2.72,22.44+1.33,25.96+2.28), p value (0.236,<0.001,<0.001,0.001), Dynamic compliance was statistically significantly lower in Group A compared to Group B and Group C at all time points, although there is no statistical difference between B,C groups, values were higher in Group C throughout. Conclusion:Application of PEEP is helpful for preserving diaphragmatic excursion during laparoscopic abdominal surgeries. In thepresent study pulmonary recruitment maneuver improved diaphragmatic excursion and dynamic compliance, although there was significant increase in peak inspiratory pressure compared to other groups.