What is the evidence for the use of low-pressure pneumoperitoneum? A systematic review

Recovery and immune function after low pressure pneumoperitoneum during robot-assisted radical prostatectomy: a randomised controlled trial

OBJECTIVE

To compare the effectiveness of low intra-abdominal pressure (IAP) facilitated by deep neuromuscular block (NMB) to standard practice in improving the quality of recovery, preserving immune function, and enhancing parietal perfusion during robot-assisted radical prostatectomy (RARP).

PATIENTS AND METHODS

In this blinded, randomised controlled trial, 96 patients were randomised to the experimental group with low IAP (8 mmHg) facilitated by deep NMB (post-tetanic count 1-2) or the control group with standard IAP (14 mmHg) and moderate NMB (train-of-four 1-2). Recovery was measured using the 40-item Quality of Recovery questionnaire and 36-item Short-Form Health survey. Immune function was evaluated by plasma damage-associated molecular patterns, cytokines, and ex vivo lipopolysaccharide-stimulated cytokine production. Parietal peritoneum perfusion was measured by analysing the recordings of indocyanine-green injection.

RESULTS

Quality of recovery was not superior in the experimental group (n = 46) compared to the control group (n = 50). All clinical outcomes, including pain scores, postoperative nausea and vomiting, and hospital stay were similar. There were no significant differences in postoperative plasma concentrations of damage-associated molecular patterns, cytokines, and ex vivo cytokine production capacity. The use of low IAP resulted in better parietal peritoneum perfusion.

CONCLUSION

Despite better perfusion of the parietal peritoneum, low IAP facilitated by deep NMB did not improve the quality of recovery or preserve immune function compared to standard practice in patients undergoing RARP.

Benefits of intratracheal and extrathoracic high-frequency percussive ventilation in a model of capnoperitoneum

Abdominal inflation with CO2 is used to facilitate laparoscopic surgeries, however, providing adequate mechanical ventilation in this scenario is of major importance during anesthesia management. We characterized high-frequency percussive ventilation (HFPV) in protecting from the gas exchange and respiratory mechanical impairments during capnoperitoneum. In addition, we aimed to assess the difference between conventional pressure-controlled mechanical ventilation (CMV) and HFPV modalities generating the high-frequency signal intratracheally (HFPVi) or extrathoracally (HFPVe). Anesthetized rabbits (n = 16) were mechanically ventilated by random sequences of CMV, HFPVi, and HFPVe. The ventilator superimposed the conventional waveform with two high-frequency signals (5 Hz and 10 Hz) during intratracheal HFPV (HFPVi) and HFPV with extrathoracic application of oscillatory signals through a sealed chest cuirass (HFPVe). Lung oxygenation index ([Formula: see text]/[Formula: see text]), arterial partial pressure of carbon dioxide ([Formula: see text]), intrapulmonary shunt (Qs/Qt), and respiratory mechanics were assessed before abdominal inflation, during capnoperitoneum, and after abdominal deflation. Compared with CMV, HFPVi with additional 5-Hz oscillations during capnoperitoneum resulted in higher [Formula: see text]/[Formula: see text], lower [Formula: see text], and decreased Qs/Qt. These improvements were smaller but remained significant during HFPVi with 10 Hz and HFPVe with either 5 or 10 Hz. The ventilation modes did not protect against capnoperitoneum-induced deteriorations in respiratory tissue mechanics. These findings suggest that high-frequency oscillations combined with conventional pressure-controlled ventilation improved lung oxygenation and CO2 removal in a model of capnoperitoneum. Compared with extrathoracic pressure oscillations, intratracheal generation of oscillatory pressure bursts appeared more effective. These findings may contribute to the optimization of mechanical ventilation during laparoscopic surgery.NEW & NOTEWORTHY The present study examines an alternative and innovative mechanical ventilation modality in improving oxygen delivery, CO2 clearance, and respiratory mechanical abnormalities in a clinically relevant experimental model of capnoperitoneum. Our data reveal that high-frequency oscillations combined with conventional ventilation improve gas exchange, with intratracheal oscillations being more effective than extrathoracic oscillations in this clinically relevant translational model.

Robotic Heller's cardiomyotomy for achalasia: early outcomes for a high-volume UK centre

INTRODUCTION

Heller's cardiomyotomy (HCM) is the gold standard treatment for achalasia. Laparoscopic HCM has been shown to be effective with low rates of symptom recurrence, though oesophageal mucosal perforation rates remain high. The aim of this prospective case series is to assess the short-term complication rates and perioperative outcomes for the first cohort of patients undergoing robotic-assisted HCM for achalasia in a single high-volume UK centre.

METHODS

Data were collected from a prospective cohort of patients who underwent robotic HCM at a single high-volume UK centre. Outcomes were assessed using the Eckhard score, which was calculated after their routine postoperative clinic appointments.

RESULTS

Thirteen patients underwent robotic HCM during the study period; this is the second largest reported case series in the European literature. There were no intraoperative oesophageal perforations. Six patients were discharged as day cases, six patients were discharged on the first postoperative day and one patient's hospital stay was two nights. There was a single perioperative complication of urinary retention. All patients reported improvement of symptoms following their operation, and all had a postoperative Eckhard score of less than 3, indicating their achalasia was in remission.

CONCLUSIONS

This cohort has demonstrated that robotic HCM has an exceptional safety profile and results in high levels of symptom resolution, even early in the learning curve. The robotic approach may be superior to laparoscopy as it allows more precise identification and dissection of the oesophageal muscle fibres, which likely reduces the risk of inadvertent mucosal damage or incomplete myotomy.

Low Pneumoperitoneum Pressure Reduces Gas Embolism During Laparoscopic Liver Resection: A Randomized Controlled Trial

OBJECTIVE

To compare the effect of low and standard pneumoperitoneal pressure (PP) on the occurrence of gas embolism during laparoscopic liver resection (LLR).

BACKGROUND

LLR has an increased risk of gas embolism. Although animal studies have shown that low PP reduces the occurrence of gas embolism, clinical evidence is lacking.

METHODS

This parallel, dual-arm, double-blind, randomized controlled trial included 141 patients undergoing elective LLR. Patients were randomized into standard ("S," 15 mm Hg; n = 70) or low ("L," 10 mm Hg; n = 71) PP groups. Severe gas embolism (≥ grade 3, based on the Schmandra microbubble method) was detected using transesophageal echocardiography and recorded as the primary outcome. Intraoperative vital signs and postoperative recovery profiles were also evaluated.

RESULTS

Fewer severe gas embolism cases (n = 29, 40.8% vs n = 47, 67.1%, P = 0.003), fewer abrupt decreases in end-tidal carbon dioxide partial pressure, shorter severe gas embolism duration, less peripheral oxygen saturation reduction, and fewer increases in heart rate and lactate during gas embolization episodes was found in group L than in group S. Moreover, a higher arterial partial pressure of oxygen and peripheral oxygen saturation were observed, and fewer fluids and vasoactive drugs were administered in group L than in group S. In both groups, the distensibility index of the inferior vena cava negatively correlated with central venous pressure throughout LLR, and a comparable quality of recovery was observed.

CONCLUSIONS

Low PP reduced the incidence and duration of severe gas embolism and achieved steadier hemodynamics and vital signs during LLR. Therefore, a low PP strategy can be considered a valuable choice for the future LLR.

Underneath Images and Robots, Looking Deeper into the Pneumoperitoneum: A Narrative Review

Laparoscopy offers numerous advantages over open procedures, minimizing trauma, reducing pain, accelerating recovery, and shortening hospital stays. Despite other technical advancements, pneumoperitoneum insufflation has received little attention, barely evolving since its inception. We explore the impact of pneumoperitoneum on patient outcomes and advocate for a minimally invasive approach that prioritizes peritoneal homeostasis. The nonlinear relationship between intra-abdominal pressure (IAP) and intra-abdominal volume (IAV) is discussed, emphasizing IAP titration to balance physiological effects and surgical workspace. Maintaining IAP below 10 mmHg is generally recommended, but factors such as patient positioning and surgical complexity must be considered. The depth of neuromuscular blockade (NMB) is explored as another variable affecting laparoscopic conditions. While deep NMB appears favorable for surgical stillness, achieving a balance between IAP and NMB depth is crucial. Temperature and humidity management during pneumoperitoneum are crucial for patient safety and optical field quality. Despite the debate over the significance of temperature drop, humidification and the warming of insufflated gas offer benefits in peritoneal homeostasis and visual clarity. In conclusion, there is potential for a paradigm shift in pneumoperitoneum management, with dynamic IAP adjustments and careful control of insufflated gas temperature and humidity to preserve peritoneal homeostasis and improve patient outcomes in minimally invasive surgery.

Impact of Standard Versus Low Pneumoperitoneum Pressure on Peritoneal Environment in Laparoscopic Cholecystectomy. Randomized Clinical Trial

BACKGROUND

High CO 2 pneumoperitoneum pressure during laparoscopy adversely affects the peritoneal environment. This study hypothesized that low pneumoperitoneum pressure may be linked to less peritoneal damage and possibly to better clinical outcomes.

MATERIALS AND METHODS

One hundred patients undergoing scheduled laparoscopic cholecystectomy were randomized 1:1 to low or to standard pneumoperitoneum pressure. Peritoneal biopsies were performed at baseline time and 1 hour after peritoneum insufflation in all patients. The primary outcome was peritoneal remodeling biomarkers and apoptotic index. Secondary outcomes included biomarker differences at the studied times and some clinical variables such as length of hospital stay, and quality and safety issues related to the procedure.

RESULTS

Peritoneal IL6 after 1 hour of surgery was significantly higher in the standard than in the low-pressure group (4.26±1.34 vs. 3.24±1.21; P =0.001). On the contrary, levels of connective tissue growth factor and plasminogen activator inhibitor-I were higher in the low-pressure group (0.89±0.61 vs. 0.61±0.84; P =0.025, and 0.74±0.89 vs. 0.24±1.15; P =0.028, respectively). Regarding apoptotic index, similar levels were found in both groups and were 44.0±10.9 and 42.5±17.8 in low and standard pressure groups, respectively. None of the secondary outcomes showed differences between the 2 groups.

CONCLUSIONS

Peritoneal inflammation after laparoscopic cholecystectomy is higher when surgery is performed under standard pressure. Adhesion formation seems to be less in this group. The majority of patients undergoing surgery under low pressure were operated under optimal workspace conditions, regardless of the surgeon's expertise.

Deep neuromuscular blockade in adults undergoing an abdominal laparoscopic procedure

BACKGROUND

Laparoscopic surgery is the preferred option for many procedures. To properly perform laparoscopic surgery, it is essential that sudden movements and abdominal contractions in patients are prevented, as it limits the surgeon's view. There has been a growing interest in the potential beneficial effect of deep neuromuscular blockade (NMB) in laparoscopic surgery. Deep NMB improves the surgical field by preventing abdominal contractions, and it is thought to decrease postoperative pain. However, it is uncertain if deep NMB improves intraoperative safety and thereby improves clinical outcomes.

OBJECTIVES

To evaluate the benefits and harms of deep neuromuscular blockade versus no, shallow, or moderate neuromuscular blockade during laparoscopic intra- or transperitoneal procedures in adults.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 31 July 2023.

SELECTION CRITERIA

We included randomised clinical trials (irrespective of language, blinding, or publication status) in adults undergoing laparoscopic intra- or transperitoneal procedures comparing deep NMB to moderate, shallow, or no NMB. We excluded trials that did not report any of the primary or secondary outcomes of our review.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. Our primary outcomes were 1. all-cause mortality, 2. health-related quality of life, and 3. proportion of participants with serious adverse events. Our secondary outcomes were 4. proportion of participants with non-serious adverse events, 5. readmissions within three months, 6. short-term pain scores, 7. measurements of postoperative recovery, and 8. operating time. We used GRADE to assess the certainty of evidence for each outcome.

MAIN RESULTS

We included 42 randomised clinical trials with 3898 participants. Most trials included participants undergoing intraperitoneal oncological resection surgery. We present the Peto fixed-effect model for most dichotomous outcomes as only sparse events were reported. Comparison 1: deep versus moderate NMB Thirty-eight trials compared deep versus moderate NMB. Deep NMB may have no effect on mortality, but the evidence is very uncertain (Peto odds ratio (OR) 7.22, 95% confidence interval (CI) 0.45 to 115.43; 12 trials, 1390 participants; very low-certainty evidence). Deep NMB likely results in little to no difference in health-related quality of life up to four days postoperative (mean difference (MD) 4.53 favouring deep NMB on the Quality of Recovery-40 score, 95% CI 0.96 to 8.09; 5 trials, 440 participants; moderate-certainty evidence; mean difference lower than the mean clinically important difference of 10 points). The evidence is very uncertain about the effect of deep NMB on intraoperatively serious adverse events (deep NMB 38/1150 versus moderate NMB 38/1076; Peto OR 0.95, 95% CI 0.59 to 1.52; 21 trials, 2231 participants; very low-certainty evidence), short-term serious adverse events (up to 60 days) (deep NMB 37/912 versus moderate NMB 42/852; Peto OR 0.90, 95% CI 0.56 to 1.42; 16 trials, 1764 participants; very low-certainty evidence), and short-term non-serious adverse events (Peto OR 0.94, 95% CI 0.65 to 1.35; 11 trials, 1232 participants; very low-certainty evidence). Deep NMB likely does not alter the duration of surgery (MD -0.51 minutes, 95% CI -3.35 to 2.32; 34 trials, 3143 participants; moderate-certainty evidence). The evidence is uncertain if deep NMB alters the length of hospital stay (MD -0.22 days, 95% CI -0.49 to 0.06; 19 trials, 2084 participants; low-certainty evidence) or pain scores one hour after surgery (MD -0.31 points on the numeric rating scale, 95% CI -0.59 to -0.03; 22 trials, 1823 participants; very low-certainty evidence; mean clinically important difference 1 point) and 24 hours after surgery (MD -0.60 points on the numeric rating scale, 95% CI -1.05 to -0.15; 16 trials, 1404 participants; very low-certainty evidence; mean clinically important difference 1 point). Comparison 2: deep versus shallow NMB Three trials compared deep versus shallow NMB. The trials did not report on mortality and health-related quality of life. The evidence is very uncertain about the effect of deep NMB compared to shallow NMB on the proportion of serious adverse events (RR 1.66, 95% CI 0.50 to 5.57; 2 trials, 158 participants; very low-certainty evidence). Comparison 3: deep versus no NMB One trial compared deep versus no NMB. There was no mortality in this trial, and health-related quality of life was not reported. The proportion of serious adverse events was 0/25 in the deep NMB group and 1/25 in the no NMB group.

AUTHORS' CONCLUSIONS

There was insufficient evidence to draw conclusions about the effects of deep NMB compared to moderate NMB on all-cause mortality and serious adverse events. Deep NMB likely results in little to no difference in health-related quality of life and duration of surgery compared to moderate NMB, and it may have no effect on the length of hospital stay. Due to the very low-certainty evidence, we do not know what the effect is of deep NMB on non-serious adverse events, pain scores, or readmission rates. Randomised clinical trials with adequate reporting of all adverse events would reduce the current uncertainties. Due to the low number of identified trials and the very low certainty of evidence, we do not know what the effect of deep NMB on serious adverse events is compared to shallow NMB and no NMB. We found no trials evaluating mortality and health-related quality of life.

The impact of AirSeal® on complications and pain management during robotic-assisted radical prostatectomy: a single-tertiary center study

PURPOSE

We aimed to compare perioperative outcomes, post-operative complications, and opioid use between AirSeal® and non-AirSeal® robotic-assisted radical prostatectomy (RARP).

METHODS

We retrospectively collected data on 326 patients who underwent elective RARP at our institution either with or without AirSeal®. The first 60 cases were excluded accounting for the institutions' learning curve of RARP. Patient demographics, oncologic, pathologic, and surgical characteristics between AirSeal® and non-AirSeal® cases were compared. Furthermore, outcomes of interest including operative time, length of stay, morbidity, and opioid use for pain management were compared between the two groups. Univariate linear and logistic regression models were developed.

RESULTS

The AirSeal® group consisted of 125 (38.3%) patients while the non-AirSeal® group consisted of 201 (61.7%) patients. No statistically significant difference was seen in terms of patient demographics, oncologic characteristics, surgical characteristics, and pathologic characteristics between the two groups. In addition, univariate linear regression showed that RARP with AirSeal® displayed shorter operative times by 12.3 min and a shorter length of hospital stay by 0.5 days compared to the non-AirSeal® group (p < 0.001). Furthermore, the AirSeal® group witnessed lower odds of Clavien-Dindo (CVD) Class > 2 complications (OR = 0.102) and a lower need for opioid use (OR = 0.49) compared to the non-AirSeal® group (p < 0.022).

CONCLUSION

RARP using AirSeal® is associated with shorter operative times, shorter length of hospital stays, lower odds of CVD > 2 complications, and lower odds of opioid use with respect to non-AirSeal® RARP. The efficacy and cost effectiveness of using the AirSeal® system during RARP should be further studied and evaluated by clinical trials.

Effect of low-pressure pneumoperitoneum on pain and inflammation in laparoscopic cholecystectomy: a randomized controlled clinical trial

OBJECTIVE

We aim to assess the effect of low-pressure pneumoperitoneum on post operative pain and ten of the known inflammatory markers.

BACKGROUND

The standard of care pneumoperitoneum set pressure in laparoscopic cholecystectomy is set to 12-14 mmHg, but many societies advocate to operate at the lowest pressure allowing adequate exposure of the operative field. Many trials have described the benefits of operating at a low-pressure pneumoperitoneum in terms of lower post operative pain, and better hemodynamic stability. But only few describe the effects on inflammatory markers and cytokines.

METHODS

A prospective, double-blinded, randomised, controlled clinical trial, including patients who underwent elective laparoscopic cholecystectomy. Patients randomised into low-pressure (8-10 mmHg) vs. standard-pressure (12-14 mmHg) with an allocation ratio of 1:1. Perioperative variables were collected and analysed.

RESULTS

one hundred patients were allocated, 50 patients in each study arm. Low-pressure patients reported lower median pain score 6-hour post operatively (5 vs. 6, p-value = 0.021) in comparison with standard-pressure group. Eight out of 10 inflammatory markers demonstrated better results in low-pressure group in comparison with standard-pressure, but the effect was not statistically significant. Total operative time and surgery difficulty was not significantly different between the two groups even in the hands of inexperienced surgeons.

CONCLUSION

low-pressure laparoscopic cholecystectomy is associated with less post operative pain and lower rise of inflammatory markers. It is feasible with comparable complications to the standard of care. Registered on ClinicalTrials.gov (NCT05530564/ September 7th, 2022).

Low-Pressure Pneumoperitoneum During Laparoscopic Sleeve Gastrectomy: a Safety and Feasibility Analysis

PURPOSE

Laparoscopy is advised under the lowest possible intra-peritoneal pressure. The aim of this study is to analyze the safety/feasibility of low pneumoperitoneum pressure (LPP) during laparoscopic sleeve gastrectomy (LSG).

MATERIALS AND METHODS

All primary LSGs who completed a 3-month follow-up were included. Re-do operations and LSGs performed with concomitant procedures were excluded. All LSGs were performed by the senior author. Upon trocar insertions, pressure was set to 10 mmHg, and the procedure was started. The pressure was increased step-wise, according to the senior author's assessment of the quality of exposure. Doing so, three pressure groups were formed: groups 1 (10 mmHg), 2 (11-13 mmHg), and 3 (14 mmHg). All data was retrieved from our database. Statistical analysis was performed using one-way ANOVA/Tukey's HSD test/Chi-square test. P values < 0.05 were regarded as significant.

RESULTS

Between February 2018 and October 2022, 708 consecutive/primary LSGs were studied. No mortality/conversion/thromboembolic event was observed. Groups 1, 2, and 3 comprised 376 (53.1%), 243 (34.3%), and 89 (12.6%) patients, respectively. Demographics, initial weight, duration of surgery, history for abdominoplasty, drain output, length of stay, and %total weight loss were evenly distributed among groups. Among 16 bleeding episodes, 14 occurred in the LPP group (p = 0.019). Including the only leak and stenosis, 8/9 of Clavien-Dindo 3b + 4 complications were observed in the LPP group (p = 0.092).

CONCLUSIONS

LSG with LPP is feasible in about half of the patients. However, almost all potentially life-threatening complications occurred in the LPP group where a significantly higher rate of bleeding was observed. Our findings suggest caution for routinely using LPP during LSG.

Synergic evacuation device helps smoke control during endoscopic thyroid surgery

BACKGROUND

Surgical plumes in small cavities, such as transoral endoscopic thyroid surgery, have never been satisfactorily resolved. We aimed to study the use of a smoke evacuation system and evaluate its efficacy, including the field of view and operating time.

STUDY DESIGN

We retrospectively reviewed 327 consecutive patients who underwent endoscopic thyroidectomy. They were separated into 2 groups based on whether the smoke evacuation system was used. To reduce the possible experience bias, only patients 4 months before and after implementing the evacuation system were included. Recorded endoscopic videos were evaluated, including the field of view, the incidence of scope clearance, and time spent during air-pocket creation.

RESULTS

Overall, there were 64 patients with a median age of 43.59 years and a median body mass index of 22.87 kg/m², including 54 women, 21 thyroid cancers, and 61 hemithyroidectomies. The operative duration was comparable between the groups. The group where the evacuation system was used scored more as good in terms of endoscopic views (8/32, 25% vs 1/32, 3.13%, P = .01), fewer incidences of endoscope lens pull out for clearance (3.5 vs 6.0 times, P < .01), less time for clear view after energy device activation (2.67 vs 5.00 seconds, P < .01), and less time spent (8.67 vs 12.38 minutes, P < .01) during air-pocket creation.

CONCLUSION

In conjunction with the synergy function of energy devices, evacuators enhance the field of view and optimize the time spent in the real clinical setting of low-pressure and small-space endoscopic thyroid procedures, in addition to the benefit of reducing smoke harm.

Low intra-abdominal pressure in laparoscopic surgery: a systematic review and meta-analysis

BACKGROUND

Guidelines do not provide clear recommendations with regard to the use of low intra-abdominal pressure (IAP) during laparoscopic surgery. The aim of this meta-analysis is to assess the influence of low versus standard IAP during laparoscopic surgery on the key-outcomes in perioperative medicine as defined by the StEP-COMPAC consensus group.

MATERIALS AND METHODS

We searched the Cochrane Library, PubMed, and EMBASE for randomized controlled trials comparing low IAP (<10 mmHg) with standard IAP (10 mmHg or higher) during laparoscopic surgery without time, language, or blinding restrictions. According to the PRISMA guidelines, two review authors independently identified trials and extracted data. Risk ratio (RR), and mean difference (MD), with 95% CIs were calculated using random-effects models with RevMan5. Main outcomes were based on StEP-COMPAC recommendations, and included postoperative complications, postoperative pain, postoperative nausea and vomiting (PONV) scores, and length of hospital stay.

RESULTS

Eighty-five studies in a wide range of laparoscopic procedures (7349 patients) were included in this meta-analysis. The available evidence indicates that the use of low IAP (<10 mmHg) leads to a lower incidence of mild (Clavien-Dindo grade 1-2) postoperative complications (RR=0.68, 95% CI: 0.53-0.86), lower pain scores (MD=-0.68, 95% CI: -0.82 to 0.54) and PONV incidence (RR=0.67, 95% CI: 0.51-0.88), and a reduced length of hospital stay (MD=-0.29, 95% CI: -0.46 to 0.11). Low IAP did not increase the risk of intraoperative complications (RR=1.15, 95% CI: 0.77-1.73).

CONCLUSIONS

Given the established safety and the reduced incidence of mild postoperative complications, lower pain scores, reduced incidence of PONV, and shorter length of stay, the available evidence supports a moderate to strong recommendation (1a level of evidence) in favor of low IAP during laparoscopic surgery.

Pneumoperitoneum and Acute Kidney Injury-An Integrative Clinical Concept Review

An increased intraabdominal pressure, particularly when occurring during periods of hemodynamic instability or fluid overload, is regarded as a major contributor to acute kidney injury (AKI) in intensive care units. During abdominal laparoscopic procedures, intraoperative insufflation pressures up to 15 mmHg are applied, to enable visualization and surgical manipulation but with the potential to compromise net renal perfusion. Despite the widely acknowledged renal arterial autoregulation, net arterial perfusion pressure is known to be narrow, and the effective renal medullary perfusion is disproportionately impacted by venous and lymphatic congestion. At present, the potential risk factors, mitigators and risk-stratification of AKI during surgical pneumoperitoneum formation received relatively limited attention among nephrologists and represent an opportunity to look beyond mere blood pressure and intake-output balances. Careful charting and reporting duration and extent of surgical pneumoperitoneum represents an opportunity for anesthesia teams to better communicate intraoperative factors affecting renal outcomes for the postoperative clinical teams. In this current article, the authors are integrating preclinical data and clinical experience to provide a better understanding to optimize renal perfusion during surgeries. Future studies should carefully consider intrabdominal insufflation pressure as a key variable when assessing outcomes and blood pressure goals in these settings.

Beyond enhanced recovery after surgery (ERAS): Evolving minimally invasive colectomy from multi-day admissions to same-day discharge

INTRODUCTION

Early discharge is increasingly important in the resource-limited COVID era. Some groups have reported early experiences with same day discharge (SDD) after colectomy. We implemented a routine SDD protocol and report the evolution in our program's outcomes.

METHODS

We studied a retrospective cohort of robotic colorectal surgeries from 2016 to 2022. Colectomies were analyzed as a sub-group and stratified by year.

RESULTS

The cohort comprised 535 cases, of which 483 were colectomies. Annual case volume increased from 58 to 180 cases (p < 0.001). Operative console time concordantly decreased by 33% (p < 0.001). Average length of stay decreased from five to one days. By 2022, 58% of colectomies were selectively discharged on the same day of surgery. Complication and readmission rates remained constant.

CONCLUSIONS

SDD is feasible and safe in selected patients. We illustrate the practical evolution of a surgical practice toward routine SDD, and discuss the factors we found critical to this transition.

Perioperative neuromuscular blockade. 2020 update of the SEDAR (Sociedad Española de Anestesiología y Reanimación) recommendations

We present an update of the 2020 Recommendations on neuromuscular blockade of the SEDAR. The previous ones dated 2009. A modified Delphi consensus analysis (experts, working group, and previous extensive bibliographic revision) 10 recommendations were produced1: neuromuscular blocking agents were recommended for endotracheal intubation and to avoid faringo-laryngeal and tracheal lesions, including critical care patients.2 We recommend not to use neuromuscular blocking agents for routine insertion of supraglotic airway devices, and to use it only in cases of airway obstruction or endotracheal intubation through the device.3 We recommend to use a rapid action neuromuscular blocking agent with an hypnotic in rapid sequence induction of anesthesia.4 We recommend profound neuromuscular block in laparoscopic surgery.5 We recommend quantitative monitoring of neuromuscular blockade during the whole surgical procedure, provided neuromuscular blocking agents have been used.6 We recommend quantitative monitoring through ulnar nerve stimulation and response evaluation of the adductor pollicis brevis, acceleromyography being the clinical standard.7 We recommend a recovery of neuromuscular block of at least TOFr ≥ 0.9 to avoid postoperative residual neuromuscular blockade.8 We recommend drug reversal of neuromuscular block at the end of general anesthetic, before extubation, provided a TOFr ≥ 0.9 has not been reached.9 We recommend to choose anticholinesterases for neuromuscular block reversal only if TOF≥2 and a TOFr ≥ 0.9 has not been attained.10 We recommend to choose sugammadex instead of anticholinesterases for reversal of neuromuscular blockade induced with rocuronium.

Automated control for investigation of the insufflation-ventilation interaction in experimental laparoscopy

In laparoscopic surgery the abdominal cavity is insufflated with pressurized carbon dioxide gas to create workspace. This pressure is exerted through the diaphragm onto the lungs, competing with ventilation and hampering it. In clinical practice the difficulty of optimizing this balance can lead to the application of harmfully high pressures. This study set out to create a research platform for the investigation of the complex interaction between insufflation and ventilation in an animal model. The research platform was constructed to incorporate insufflation, ventilation and relevant hemodynamic monitoring devices, controlling insufflation and ventilation from a central computer. The core of the applied methodology is the fixation of physiological parameters by applying closed-loop control of specific ventilation parameters. For accurate volumetric measurements the research platform can be used in a CT scanner. An algorithm was designed to keep blood carbon dioxide and oxygen values stable, minimizing the effect of fluctuations on vascular tone and hemodynamics. This design allowed stepwise adjustment of insufflation pressure to measure the effects on ventilation and circulation. A pilot experiment in a porcine model demonstrated adequate platform performance. The developed research platform and protocol automation have the potential to increase translatability and repeatability of animal experiments on the biomechanical interactions between insufflation and ventilation.

Comparison of Different Carbon Dioxide Insufflation Rates on Hemodynamic Changes in Laparoscopic Surgeries: A Randomized Controlled Trial

Introduction The injury and detrimental effects of carbon dioxide (CO2) insufflation during laparoscopic surgeries may be due to the higher flow rates used during insufflation. The aim of our study was to study the effects of different CO2 insufflation flow rates on hemodynamic parameters in laparoscopic surgeries. The secondary objectives were to compare the patient and surgeon satisfaction scores, postoperative shoulder scores, and surgical site pain scores. Methods This prospective, randomized, double-blinded trial was commenced after institutional ethical committee approval and The Clinical Trials Registry- India (CTRI) registration (CTRI 2021/10/037595). Ninety patients scheduled for laparoscopic cholecystectomy were randomly divided into three groups based on CO2 insufflation flow rate by computer-generated random numbers and the sealed envelope method: Group-A: 5 L/min; Group-B: 10 L/min; and Group-C: 15 L/min. General anesthesia was standardized in all three groups. Mean arterial pressure (MAP) and heart rate were recorded at different timelines, which included the arrival in the operating room (T0), just before the induction of anesthesia (T1), at the beginning of pneumoperitoneum (T2), 10 minutes (T3), 20 minutes (T4), 30 minutes (T5), and 60 minutes (T6) after the pneumoperitoneum, at the end of the operation (T7), five minutes (T8), and 15 minutes (T9) after arriving at the recovery room. The patient and surgeon satisfaction scores were assessed on a 5-point Likert scale. The visual analog score (VAS) was used to assess the surgical site pain and shoulder pain every four hours for 24 hours. The continuous data were assessed by one-way analysis of variance (ANOVA), and the categorical data were assessed by the Chi-square test. The sample size was estimated based on a pilot study and using the G Power 3.1.9.2 Program (Universitat Kiel, Germany) calculator. Results There was an increase in the mean arterial pressure (MAP) between the groups 60 min after pneumoperitoneum creation with higher flow rates. The baseline MAP was 85.76± 10.11 in group A, 86.03± 9.79 in group B, and 88.13± 8.46 in group C. At 60 min from the creation of the pneumoperitoneum, the MAP increased significantly from 99.17 ± 9.35 in group A, 102.43 ± 8.24 in group B, to 106.83 ± 8.31 in group C. This was statistically significant with a p-value of 0.004. There was a statistically significant difference in heart rate between the groups 10 minutes after pneumoperitoneum creation. No complications were reported in any of the groups. The postoperative shoulder pain was more severe when higher flows were used at 20 and 24 hours. The surgical site pain was also significantly more for up to 12 hours following surgery with higher flows. Conclusion We conclude that low-flow CO2 insufflation during laparoscopic surgeries is associated with fewer hemodynamic changes, better patient satisfaction scores, and lower postoperative pain scores.

Accelerated 23-h enhanced recovery protocol for colon surgery: the CHASE-study

The introduction of the Enhanced Recovery After Surgery (ERAS) program has radically improved postoperative outcomes in colorectal surgery. Optimization of ERAS program to an accelerated recovery program may further improve these said outcomes. This single-center, prospective study investigated the feasibility and safety of a 23-h accelerated enhanced recovery protocol (ERP) for colorectal cancer patients (ASA I-II) undergoing elective laparoscopic surgery. The 23-h accelerated ERP consisted of adjustments in pre-, peri- and postoperative care; this was called the CHASE-protocol. This group was compared to a retrospective cohort of colorectal cancer patients who received standard ERAS care. Patients were discharged within 23 h after surgery if they met the discharge criteria. Primary outcome was the rate of the successful discharge within 23 h. Successful discharge within the CHASE-cohort was realized in 33 out of the 41 included patients (80.5%). Compared to the retrospective cohort (n = 75), length of stay was significantly shorter in the CHASE-cohort (p = 0.000), and the readmission rate was higher (p = 0.051). Complication rate was similar, severe complications were observed less frequently in the CHASE-cohort (4.9% vs. 8.0%). Findings from this study support the feasibility and safety of the accelerated 23-h accelerated ERP with the CHASE-protocol in selected patients.

Early Postoperative Low Compliance to Enhanced Recovery Pathway in Rectal Cancer Patients

Early postoperative low compliance to enhanced recovery protocols has been associated with morbidity following colon surgery. The purpose of this study is to evaluate the possible causes of early postoperative low compliance to the enhanced recovery pathway and its relationship with morbidity following rectal surgery for cancer. A total of 439 consecutive patients who underwent elective surgery for rectal cancer have been included in the study. Compliance to enhanced recovery protocol on postoperative day (POD) 2 was evaluated in all patients. Indicators of compliance were naso-gastric tube and urinary catheter removal, recovery of both oral feeding and mobilization, and the stopping of intravenous fluids. Low compliance on POD 2 was defined as non- adherence to two or more items. One-third of patients had low compliance on POD 2. Removal of urinary catheter, intravenous fluids stop, and mobilization were the items with lowest adherence. Advanced age, duration of surgery, open surgery and diverting stoma were predictive factors of low compliance at multivariate analysis. Overall morbidity and major complications were significantly higher (p < 0.001) in patients with low compliance on POD 2. At multivariate analysis, failure to remove urinary catheter on POD 2 (OR = 1.83) was significantly correlated with postoperative complications. Low compliance to enhanced recovery protocol on POD 2 was significantly associated with morbidity. Failure to remove the urinary catheter was the most predictive indicator. Advanced age, long procedure, open surgery and diverting stoma were independent predictive factors of low compliance.

Effects of deep neuromuscular block on surgical pleth index-guided remifentanil administration in laparoscopic herniorrhaphy: a prospective randomized trial

Deep neuromuscular block (NMB) has been increasingly utilized, but its role in reducing intraoperative opioid requirement has yet to be investigated. Surgical pleth index (SPI) quantifies nociception. We investigated the effects of deep NMB on SPI-guided remifentanil administration in laparoscopic herniorrhaphy. Total 128 patients undergoing laparoscopic inguinal herniorrhaphy were randomly allocated to two groups of NMB: deep (n = 64) and moderate (n = 64). The remifentanil dose was assessed during intubation, from skin incision until CO₂ insertion, and pneumoperitoneum. Mean infusion rate of remifentanil during pneumoperitoneum was higher in moderate NMB group than in deep NMB group (0.103 [0.075-0.143] µg/kg/min vs. 0.073 [0.056-0.097] µg/kg/min, p < 0.001). Consequently, median infusion rate of remifentanil during anesthesia was higher in moderate NMB group (0.076 [0.096-0.067] µg/kg/min vs. 0.067 [0.084-0.058] µg/kg/min, p = 0.016). The duration of post-anesthesia care unit stay was longer in the moderate NMB group (40 [30-40] min vs. 30 [30-40] min, p = 0.045). In conclusion, deep NMB reduced the remifentanil requirement compared with moderate NMB in SPI-guided anesthesia for laparoscopic herniorrhaphy.

Clinical outcomes of low-pressure pneumoperitoneum in minimally invasive urological surgery

The adoption of minimally invasive laparoscopic techniques has revolutionised urological practice. This necessitates a pneumoperitoneum (PNP) and the impact the PNP pressure has on post-operative outcomes is uncertain. During the current COVID-19 era guidance has suggested the utilisation of lower PNP pressures to mitigate the risk of intra-operative viral transmission. Review the current literature regarding the impact of pneumoperitoneum pressure, within the field of urology, on post-operative outcomes. A search of the PubMed, Medline and EMBASE databases was undertaken to identify studies that met the inclusion criteria. The Preferred Reporting Items for Systematic Reviews (PRISMA) guidelines were adhered to. Ten studies, that included both randomised controlled trials and retrospective case series reviews, were identified that met the inclusion criteria. The effect of PNP pressure on outcomes following prostatectomy, live donor nephrectomy, partial nephrectomy and a variety of benign upper tract procedures were discussed. Low pressure PNP appears safe when compared to high pressure PNP, potentially reducing post-operative pain and rates of ileus. When compared to general surgery, there is a lack of quality evidence investigating the impact of PNP pressures on outcomes within urology. Low pressure PNP appears non-inferior to high pressure PNP. More research is required to validate this finding, particularly post-cystectomy and nephrectomy.

The impact of low-pressure pneumoperitoneum on robotic-assisted radical cystectomy and intracorporeal ileal conduit urinary diversion: a case-control study

Purpose

To evaluate the role of low intra-abdominal pressure (IAP) in improving postoperative recovery in Robotic-assisted radical cystectomy (RARC) and intracorporeal ileal conduit urinary diversion (ICUD).

Methods

A retrospective case–control study of 49 bladder cancer patients offered RARC/ICUD with standard (12 mmHg, n = 24) or low IAP (8 mmHg, n = 25). Outcomes of interest included length of procedure (LoP), estimated blood loss (EBL), blood transfusion, margin positivity rates, time to first flatus (TtFF), time to first bowel movement (TtFBM), ileus and small bowel obstruction (SBO) rates, time to safe discharge (TtSD), postoperative hospital stay (PHS) and pain levels on a postoperative day (POD) 1 and 3. Perioperative complications were recorded using the Clavien-Dindo system.

Results

Demographic and baseline clinical characteristics, LoP, EBL and margin positivity rates were similar between groups. No transfusions were recorded. Median (IQR) TtFF, TtFBM and TtSD were significantly longer in Group 1 vs Group 2 (4 (1) vs 2 (1), 7 (3) vs 6 (2) and 8.5 (5.75) vs 5.0 (1), respectively). PHS and rates of postoperative ileus and SBO were lower in Group 2, however not statistically significant. Severe pain was uncommon in both groups but moderate/severe pain was significantly higher in Group 1 (95.8% vs 48% on POD1 and 62.5% vs 16% on POD3). No significant intraoperative complications were recorded and ≥ Grade 3 postoperative complications at 30 and 90 days were similar.

Conclusion

With limitations, Low-IAP RARC can be safely offered to RARC/ICUD patients and leads to faster bowel recovery, and shorter time to safe discharge compared to standard pneumoperitoneum.

Lower vs standard pressure pneumoperitoneum in robotic-assisted radical prostatectomy: a systematic review and meta-analysis

Robotic-assisted laparoscopic radical prostatectomy (RARP) has been traditionally performed at a pneumoperitoneum insufflation pressure of 12-15 mmHg. This meta-analysis and systematic review aims to assess the current evidence comparing lower to standard pressure pneumoperitoneum in RARP. Systematic searches of MEDLINE, COCHRANE, SCOPUS and EMBASE were performed to identify articles published up until November 2021 comparing lower pressure with standard pressure pneumoperitoneum in RARP. Standard pressure was defined as > 12 mmHg and lower pressure ≤ 12 mmHg. Estimated blood loss, length of operation, length of hospital stay, post-operative ileus, 30-day readmissions, Clavien-Dindo complications and rate of positive surgical margins were extracted as endpoints of interest. Our searches identified 165 abstracts of which 4 articles with 1319 patients were eligible. Cumulative analysis demonstrated reduced length of stay when a lower pressure was used: WMD - 0.23 (- 0.45 to - 0.02) days (p = 0.03) as well as a reduced rate of post-operative ileus: OR 0.41 (0.22 to 0.77) (p = 0.006). There was no significant increase in length of operation WMD - 1.79 (- 15.96 to 12.38) (p = 0.8), estimated blood loss WMD - 2.89 (- 29.41 to 23.62) (p = 0.83), 30-day readmissions or positive surgical margins OR 1.04 (0.78 to 1.38) (p = 0.81) and RD - 0.01 (- 0.04 to 0.01) (p = 0.3) when using a lower pressure. We have demonstrated reduced length of stay and rates of post-operative ileus, when performing RARP at a lower pressure without a significant increase in length of operation, estimated blood loss, positive surgical margins or complications. The recommendation to use lower pressure pneumoperitoneum is moderate to weak and more randomised control trials are required to validate these results.

Intraperitoneal Instillation of Local Anesthetic (IPILA) in Bariatric Surgery and the Effect on Post-operative Pain Scores: a Randomized Control Trial

BACKGROUND

Effective analgesia after bariatric procedures is vital as it can reduce post-operative opioid use. This leads to less nausea which may be associated with shorter post-operative length of stay (LOS). Understanding analgesic requirements in patients with obesity is important due to the varied physiology and increased number of comorbidities.

OBJECTIVES

The aim of this study was to evaluate the efficacy of intraperitoneal instillation of local anesthetic (IPILA) to reduce opioid requirements in patients undergoing laparoscopic bariatric surgery.

METHODS

A double-blinded randomized control trial was conducted to compare intraperitoneal instillation of ropivacaine to normal saline in 104 patients undergoing bariatric surgery. The primary endpoint was pain in recovery with secondary endpoints at 1, 2, 4, 6, 24, and 48 h post-operatively. Further endpoints were post-operative analgesic use and LOS. Safety endpoints included unexpected reoperation or readmission, complications, and mortality.

RESULTS

There were 54 patients in the placebo arm and 50 in the IPILA. Pain scores were significantly lower in the IPILA group both at rest (p = 0.04) and on movement (p = 0.02) in recovery with no difference seen at subsequent time points. Equally, IPILA was independently associated with reducing severe post-operative pain at rest and movement (adjusted odds ratio [aOR] 0.28, 95% CI 0.11-0.69, p = 0.007 and aOR 0.25, 95% CI 0.09-0.62, p = 0.004, respectively). There was no significant difference in LOS, opioid use, antiemetic use, morbidity, or mortality between the intervention and placebo groups.

CONCLUSION

The administration of ropivacaine intraperitoneally during laparoscopic bariatric surgery reduces post-operative pain in the recovery room but does not reduce opioid use nor LOS.

Percutaneous delivery of self-propelling hemostatic powder for managing non-compressible abdominal hemorrhage: a proof-of-concept study in swine

INTRODUCTION

Non-compressible intra-abdominal hemorrhage (NCIAH) is a major cause of preventable death on the battlefield and in civilian trauma. Currently, it can only be definitively managed with surgery, as there are limited strategies for controlling ongoing NCIAH in the prehospital environment. We hypothesized that a self-propelling thrombin-containing powder (SPTP) could increase survival in a swine model of NCIAH when delivered percutaneously into the closed abdomen using an engineered spray system.

MATERIALS AND METHODS

Nineteen swine underwent surgical laparotomy followed by a Grade V liver injury that created massive hemorrhage, before closing the abdomen with sutures. Animals either received treatment with standard of care fluid resuscitation (n=9) or the SPTP spray system (n=10), which consisted of a spray device and a 14 Fr catheter. Using the spray system, SPTP was delivered into a hemoperitoneum identified using a focused assessment with sonography in trauma (FAST) exam. Lactated Ringer's solution was administered to all animals to maintain a mean arterial pressure (MAP) of >50 mmHg. The primary outcome was percentage of animals surviving at three hours following injury.

RESULTS

In the swine model of NCIAH, a greater percentage of animals receiving SPTP survived to three hours, although differences were not significant. The SPTP spray system increased the median survival of animals from 1.6 hr in the fluid resuscitation group to 4.3 hr. The SPTP spray system delivered a total mass of 18.5 ± 1.0 g of SPTP. The mean change in intra-abdominal pressure following SPTP delivery was 5.2 ± 1.8 mmHg (mean ± SEM). The intervention time was 6.7 ± 1.7 min. No adverse effects related to the SPTP formulation or the spray system were observed. SPTP was especially beneficial in animals that had either severely elevated lactate concentrations or low mean arterial pressure of <35 mmHg shortly after injury.

CONCLUSIONS

This demonstrates proof-of-concept for use of a new minimally invasive procedure for managing NCIAH, which could extend survival time to enable patients to reach definitive surgical care.

Low-pressure versus standard-pressure pneumoperitoneum in laparoscopic cholecystectomy: a systematic review and meta-analysis of randomized controlled trials

Introduction

It has been previously demonstrated that the rise of intra-abdominal pressures and prolonged exposure to such pressures can produce changes in the cardiovascular and pulmonary dynamic which, though potentially well tolerated in the majority of healthy patients with adequate cardiopulmonary reserve, may be less well tolerated when cardiopulmonary reserve is poor.

Nevertheless, theoretically lowering intra-abdominal pressure could reduce the impact of pneumoperitoneum on the blood circulation of intra-abdominal organs as well as cardiopulmonary function. However, the evidence remains weak, and as such, the debate remains unresolved. The aim of this systematic review and meta-analysis was to demonstrate the current knowledge around the effect of pneumoperitoneum at different pressures levels during laparoscopic cholecystectomy.

Materials and methods

This systematic review and meta-analysis were reported according to the recommendations of the 2020 updated Preferred Reporting Items for Systematic reviews and Meta-analyses (PRISMA) guidelines, and the Cochrane handbook for systematic reviews of interventions.

Results

This systematic review and meta-analysis included 44 randomized controlled trials that compared different pressures of pneumoperitoneum in the setting of elective laparoscopic cholecystectomy. Length of hospital, conversion rate, and complications rate were not significantly different, whereas statistically significant differences were observed in post-operative pain and analgesic consumption. According to the GRADE criteria, overall quality of evidence was high for intra-operative bile spillage (critical outcome), overall complications (critical outcome), shoulder pain (critical outcome), and overall post-operative pain (critical outcome). Overall quality of evidence was moderate for conversion to open surgery (critical outcome), post-operative pain at 1 day (critical outcome), post-operative pain at 3 days (important outcome), and bleeding (critical outcome). Overall quality of evidence was low for operative time (important outcome), length of hospital stay (important outcome), post-operative pain at 12 h (critical outcome), and was very low for post-operative pain at 1 h (critical outcome), post-operative pain at 4 h (critical outcome), post-operative pain at 8 h (critical outcome), and post-operative pain at 2 days (critical outcome).

Conclusions

This review allowed us to draw conclusive results from the use of low-pressure pneumoperitoneum with an adequate quality of evidence.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00464-022-09201-1.

Perioperative parameters to consider for enhanced recovery in surgery (ERS) in gynecology (excluding breast surgery)

The current review explores the Enhanced Rehabilitation in Surgery (ERS) approach in the specific context of gynecological surgery. Implementation of an ERS protocol in gynecological surgery reduces postoperative complications and length of stay without increasing morbidity. An ERS approach is based on maintaining an adequate diet and hydration before the operation, according to the recommended time frame, to reduce the phenomenon of insulin resistance, and to optimize patient comfort. On the other hand, the use of anxiolytic treatment as premedication is not recommended. Systematic preoperative digestive preparation, a source of patient discomfort, is not associated with an improvement in the postoperative functional outcome or with a reduction in the rate of complications. A minimally invasive surgical approach is preferrable in the context of ERS. Prevention of surgical site infection includes measures such as optimized antibiotic prophylaxis, skin disinfection with alcoholic chlorhexidine, reduction in the use of drainage of the surgical site, and prevention of hypothermia. Early removal of the bladder catheter is associated with a reduction in the risk of urinary tract infection and a reduction in the length of hospital stay. Prevention of postoperative ileus is based on early refeeding, and prevention of postoperative nausea-vomiting in a multimodal strategy to be initiated during the intraoperative period. Intraoperative hydration should be aimed at achieving euvolemia. Pain control is based on a multimodal strategy to spare morphine use and may include locoregional analgesia. Medicines should be administered orally during the postoperative period to hasten the resumption of the patient's autonomy. The prevention of thromboembolic risk is based on a strategy combining drug prophylaxis, when indicated, and mechanical restraint, as well as early mobilization. However, the eclectic nature of the implementation of these measures as reported in the literature renders their interpretation difficult. Furthermore, beyond the application of one of these measures in isolation, the best benefit on the postoperative outcome is achieved by a combination of measures which then constitutes a global strategy allowing the objectives of the ERS to be met.

The effect of anesthetic agents on intraocular pressure during laparoscopic gynecological surgery performed in the Trendelenburg position: A randomized clinical trial

BACKGROUND

Intraocular pressure (IOP) increases due to pneumoperitoneum and the Trendelenburg position during laparo-scopic surgery. Apart from ketamine and suxamethonium, anesthetic agents generally reduce IOP by various extents. The present study investigated the effects of combinations of four anesthetic agents on IOP during laparoscopic gynecological surgery.

METHODS

Patients (n=100) were assigned to one of the four groups: Group 1 (n=25; pentothal induction + desflurane/remifen-tanil maintenance), Group 2 (n=25; propofol induction + sevoflurane/remifentanil maintenance), Group 3 (n=25; propofol induction + desflurane/remifentanil maintenance), and Group 4 (n=25; pentothal induction + sevoflurane/remifentanil maintenance). The IOPs recorded before anesthesia induction, after intubation, after carbon dioxide insufflation, in the Trendelenburg position, and after ex-tubation were compared among the groups. Hemodynamic parameters were also evaluated.

RESULTS

Induction in Group 2 and Group 3 used propofol. When the IOP in the Trendelenburg position was compared with the IOP before induction, there was no statistically significant difference in Groups 2 and 3 (p>0.05). In Groups 1 and 4, pentothal was used for induction. The IOP in Groups 1 and 4 was statistically significantly higher in the Trendelenburg position than it was before induction (0.027-0.001).

CONCLUSION

To minimize the variation in IOP in the Trendelenburg position during laparoscopic gynecological surgeries, we recommend the use of propofol for induction, independent of desflurane or sevoflurane use.

Proposal of a Novel Index of Abdominal Compliance and the Association With Postoperative Pain After Laparoscopic Inguinal Hernia Repair

BACKGROUND

In laparoscopic surgery, low pneumoperitoneum pressure is reported to reduce pain, which suggests that easing abdominal expansion is crucial for less postoperative pain. However, although abdominal compliance (AC) is associated with the degree of abdominal expansion, the role of AC in pain by pneumoperitoneum is unknown. In this study, we devised a novel index as a surrogate of AC to evaluate the association between AC and postoperative pain in laparoscopic inguinal hernia repair.

MATERIALS AND METHODS

We reviewed 83 patients who underwent elective transabdominal preperitoneal repair from 2019 to 2021 at Heisei Memorial Hospital. Insufflation pressure was set to low pressure (8 mm Hg). The abdominal compliance index [ACI; insufflated intra-abdominal volume (L)/body surface area (m2)] was utilized to evaluate the association between AC and postoperative pain.

RESULTS

ACI was evaluated in 30 patients. Median ACI was 1.53 (1.00 to 2.48) L/m2. Although there was no difference in the average body constitution, the high ACI group (n=15) had significantly higher intra-abdominal volume at 8 mm Hg pressure, compared with the low ACI group (n=15) (3.1 vs. 2.1 L, P<0.0001). The high ACI group had significantly higher pain than the low ACI group on the day of surgery (2.0 vs. 1.0, P=0.006) and the day after (0.8 vs. 0.3, P=0.007). In addition, 46.7% of the patients in the high ACI group experienced pneumoperitoneum-associated pain, whereas patients in the low ACI group experienced incision pain only. Additional analgesics were administered in 53.3% of the high ACI group, compared with 33.3% in the low ACI group.

CONCLUSIONS

AC was suggested to be a vital factor of postoperative pain after laparoscopic inguinal hernia repair. Patients with high AC may be susceptible to higher pain by pneumoperitoneum, even in low-pressure settings.

Does deep neuromuscular blockade provide improved outcomes in low pressure laparoscopic colorectal surgery? A single blinded randomized pilot study

BACKGROUND

Low intra-abdominal pressure during laparoscopic colorectal surgery may improve outcomes and reduce hospital stay, in addition to Enhanced Recovery After Surgery (ERAS) protocols. There is concern that low pressure reduces laparoscopic vision and may increase surgical complications. Deep neuromuscular blockade may abrogate any reduction in vision of low-pressure pneumoperitoneum. However, antagonism of deep neuromuscular blockade at completion of surgery necessitates the use of sugammadex, which is prohibitively expensive, if there are no surgical benefits and warrants further study.

METHODS

A single institution, single blinded randomized controlled pilot study was performed comparing deep to moderate neuromuscular blockade in major laparoscopic colorectal surgery.

RESULTS

Thirty-eight patients were randomized to deep or moderate neuromuscular blockade. There were no statistically significant differences between groups, when comparing key patient demographics, or surgeon satisfaction with view, which required increased pressure or further relaxation demands. The deep blockade group had increased QoR15 scores and a decrease in pain, C-Reactive Protein (CRP) measurements and operating times, although were non-significant. The moderate group had slightly higher incidents of Medical Emergency Team (MET) calls and more severe complications, although were non-significant.

CONCLUSIONS

Low intra-abdominal pressure in laparoscopic colorectal surgery is feasible and allows adequate surgical visualization, regardless of the degree of neuromuscular blockade. Potential benefits of deep neuromuscular blockade may include improved pain and quality of recovery and a possible reduction of complications; however a larger cohort is required to confirm this. Future ERAS protocols may consider deep neuromuscular blockade with low intra-abdominal pressure to further benefit patients.

The effect of different pressures of pneumoperitoneum on the dimensions of internal jugular vein – A prospective double-blind, randomised study

Background and Aims:

During laparoscopic surgeries, pneumoperitoneum increases intraabdominal pressure (IAP) which can increase the central venous pressure (CVP), and significant haemodynamic changes. In this study, we evaluated the effect of two different pressures of pneumoperitoneum, standard (13-15 mmHg), and low (6-8 mmHg) on the cross-sectional area (CSA) of the internal jugular vein (IJV) using ultrasonography, haemodynamic changes and duration of surgery. Surgeon’s comfort and feasibility of performing laparoscopic surgeries with low pressure pneumoperitoneum was also studied.

Methods:

This prospective, double-blind, randomised study included 148 patients of American Society of Anesthesiologists physical status class I and II undergoing laparoscopic surgeries. They were allocated into two groups: group S (standard) (number (n) = 73) had the IAP maintained between 13-15 mmHg; group L (low) had an IAP of 6-8 mmHg (n = 75). CSA of right IJV was measured before induction of anaesthesia (T1), 5 min after intubation (T2), 5 min after pneumoperitoneum (T3), before desufflation (T4) and 5 min prior to extubation (T5). Chi-square test, and Student’s paired and unpaired t test were used for statistical analysis.

Results:

The increase in IJV CSA at T3 when compared to T2 was statistically significant in both the groups (P < 0.001). On desufflation, the change in IJV CSA showed significant decrease in T5 value than T4 value in both the groups (P < 0.001). However, the percentage change in the IJV CSA was more in group S (35.4%) than group L (21.2%).

Conclusion:

CSA of IJV increased significantly even with lower IAP of 6-8 mmHg. Laparoscopic surgery can be performed conveniently even at low IAP.

Deep neuromuscular block reduces the incidence of intra-operative complications during laparoscopic donor nephrectomy: a pooled analysis of randomized controlled trials

Study objective

To assess whether different intensities of intra-abdominal pressure and deep neuromuscular blockade influence the risk of intra-operative surgical complications during laparoscopic donor nephrectomy.

Design

A pooled analysis of ten previously performed prospective randomized controlled trials.

Setting

Laparoscopic donor nephrectomy performed in four academic hospitals in the Netherlands: Radboudumc, Leiden UMC, Erasmus MC Rotterdam, and Amsterdam UMC.

Patients

Five hundred fifty-six patients undergoing a transperitoneal, fully laparoscopic donor nephrectomy enrolled in ten prospective, randomized controlled trials conducted in the Netherlands from 2001 to 2017.

Interventions

Moderate (tetanic count of four > 1) versus deep (post-tetanic count 1–5) neuromuscular blockade and standard (≥10 mmHg) versus low (<10 mmHg) intra-abdominal pressure.

Measurements

The primary endpoint is the number of intra-operative surgical complications defined as any deviation from the ideal intra-operative course occurring between skin incision and closure with five severity grades, according to ClassIntra. Multiple logistic regression analyses were used to identify predictors of intra- and postoperative complications.

Main results

In 53/556 (9.5%) patients, an intra-operative complication with ClassIntra grade ≥ 2 occurred. Multiple logistic regression analyses showed standard intra-abdominal pressure (OR 0.318, 95% CI 0.118–0.862; p = 0.024) as a predictor of less intra-operative complications and moderate neuromuscular blockade (OR 3.518, 95% CI 1.244–9.948; p = 0.018) as a predictor of more intra-operative complications. Postoperative complications occurred in 31/556 (6.8%), without significant predictors in multiple logistic regression analyses.

Conclusions

Our data indicate that the use of deep neuromuscular blockade could increase safety during laparoscopic donor nephrectomy. Future randomized clinical trials should be performed to confirm this and to pursue whether it also applies to other types of laparoscopic surgery.

Trial registration

Clinicaltrials.gov LEOPARD-2 (NCT02146417), LEOPARD-3 trial (NCT02602964), and RELAX-1 study (NCT02838134), Klop et al. (NTR 3096), Dols et al. 2014 (NTR1433).

Gas embolism under standard versus low pneumoperitoneum pressure during laparoscopic liver resection (GASES): study protocol for a randomized controlled trial

Background

Gas embolism induced by CO₂ pneumoperitoneum is commonly identified as a risk factor for morbidity, especially cardiopulmonary morbidity, after laparoscopic liver resection (LLR) in adults. Increasing pneumoperitoneum pressure (PP) contributes to gas accumulation following laparoscopy. However, few studies have examined the effects of PP in the context of LLR. In LLR, the PP-central venous pressure (CVP) gradient is increased due to hepatic vein rupture, hepatic sinusoid exposure, and low CVP management, which together increase the risk of CO₂ embolization. The aim of this study is to primarily determine the role of low PP (10 mmHg) on the incidence of severe gas embolism.

Methods

Adult participants (n = 140) undergoing elective LLR will be allocated to either a standard (15 mmHg) or low (10 mmHg) PP group. Anesthesia management, postoperative care, and other processes will be performed similarly in both groups. The occurrence of severe gas embolism, which is defined as gas embolism ≥ grade 3 according to the Schmandra microbubble method, will be detected by transesophageal echocardiography (TEE) and recorded as the primary outcome. The subjects will be followed up until discharge and followed up by telephone 1 and 3 months after surgery. Postoperative outcomes, such as the Post-Operative Quality of Recovery Scale, pain severity, and adverse events, will be assessed. Serum cardiac markers and inflammatory factors will also be assessed during the study period. The correlation between intraoperative inferior vena cava-collapsibility index (IVC-CI) under TEE and central venous pressure (CVP) will also be explored.

Discussion

This study is the first prospective randomized clinical trial to determine the effect of low versus standard PP on gas embolism using TEE during elective LLR. These findings will provide scientific and clinical evidence of the role of PP.

Trial status

Protocol version: version 1 of 21-08-2020

Trial registration

ChiCTR2000036396 (http://www.chictr.org.cn). Registered on 22 August 2020.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05678-8.

Reduced Laparoscopic Intra-abdominal Pressure During Laparoscopic Cholecystectomy and Its Effect on Post-operative Pain: a Double-Blinded Randomised Control Trial

BACKGROUND

Laparoscopic surgery is regarded as the gold standard for the surgical management of cholelithiasis. To improve post-operative pain, low-pressure laparoscopic cholecystectomies (LPLC) have been trialed. A recent systematic review found that LPLC reduced pain; however, many of the randomised control trials were at a high risk of bias and the overall quality of evidence was low.

METHODS

One hundred patients undergoing elective laparoscopic cholecystectomy were randomised to a LPLC (8 mmHg) or a standard pressure laparoscopic cholecystectomy (12 mmHg) (SPLC) with surgeons and anaesthetists blinded to the pressure. Pressures were increased if vision was compromised. Primary outcomes were post-operative pain and analgesia requirements at 4-6 h and 24 h.

RESULTS

Intra-operative visibility was significantly reduced in LPLC (p<0.01) resulting in a higher number of operations requiring the pressure to be increased (29% vs 8%, p=0.010); however, there were no differences in length of operation or post-operative outcomes. Pain scores were comparable at all time points across all pressures; however, recovery room fentanyl requirement was more than four times higher when comparing 8 to 12 mmHg (12.5mcg vs 60mcg, p=0.047). Nausea and vomiting was also higher when comparing these pressures (0/36 vs 7/60, p=0.033). Interestingly, when surgeons estimated the operating pressure, they were correct in only 69% of cases.

CONCLUSION

Although pain scores were similar, there was a significant reduction in fentanyl requirement and nausea/vomiting in LPLC. Although LPLC compromised intra-operative visibility requiring increased pressure in some cases, there was no difference in complications, suggesting LPLC is safe and beneficial to attempt in all patients.

TRIAL REGISTRATION

Registered with the Australia and New Zealand Clinical Trials Registry (ACTRN12619000205134).

Quality of recovery in patients under low- or standard-pressure pneumoperitoneum. A randomised controlled trial

BACKGROUND

The use of low-pressure pneumoperitoneum seems to be capable of reducing complications such as post-operative pain. However, the quality of evidence supporting this conclusion is low. Both the lack of investigator blinding to both intra-abdominal pressure and to method of neuromuscular blockade represent key sources of bias. Hence, this prospective, randomised, and double-blind study aimed to compare the quality of recovery (Questionnaire QoR-40) of patients undergoing laparoscopic cholecystectomy under low-pressure and standard-pressure pneumoperitoneum. We tested the hypothesis that low pneumoperitoneum pressure enhances the quality of recovery following LC.

METHODS

Eighty patients who underwent elective laparoscopic cholecystectomy were randomly divided into two groups, a low-pressure (10 mm Hg) pneumoperitoneum group and a standard-pressure (14 mm Hg) pneumoperitoneum group. For all participants, the value of the insufflation pressure was kept hidden and only the nurse responsible for the operating room was aware of it. Deep neuromuscular blockade was induced for all cases [train-of-four (TOF) = 0; post-tetanic count (PTC) > 0]. The quality of recovery was assessed on the morning of first post-operative day.

RESULTS

No difference was found in either total score or in its different dimensions according to the QoR-40 questionnaire. The patients in the low-pressure pneumoperitoneum group experienced more pain during forced coughing measured at 4 hours (median difference [95% CI], 1 [0-2]; P = .030), 8 hours (1 [0-2]; P = .030) and 12 hours (0 [0-1] P = .025) after discharge from the post-anaesthesia care unit, when compared with those in the standard-pressure pneumoperitoneum group.

CONCLUSION

We thus conclude that the use of low-pressure pneumoperitoneum during elective laparoscopic cholecystectomy does not improve the quality of recovery.

Low-pressure Pneumoperitoneum With Abdominal Wall Lifting Versus Standard Pressure Pneumoperitoneum in Laparoscopic Fundoplication for Gastroesophageal Reflux Disease: A Propensity Score-matched Analysis

OBJECTIVE

The objective of this study was to compare the treatment results of low-pressure pneumoperitoneum with abdominal wall lifting (AWL+LP, 6 mm Hg) versus standard pressure pneumoperitoneum (SP, 12 mm Hg) during laparoscopic fundoplication for gastroesophageal reflux disease (GERD), using propensity score matching (PSM).

MATERIALS AND METHODS

A retrospective analysis was made of 362 patients, 123 in the AWL+LP group and 239 in the SP group, who underwent laparoscopic fundoplication for GERD from January 2010 to December 2017. Perioperative and prognostic outcomes were compared after PSM with 1:1 match.

RESULTS

After PSM, 107 matched pairs were obtained. Compared with the SP group at 30 and 60 minutes after pneumoperitoneal initiation, the AWL+LP group showed significantly lower end-tidal carbon dioxide value (P<0.001, <0.001, respectively), lower partial pressure of carbon dioxide value (P<0.001, 0.016, respectively) and significantly higher pH value (P<0.001, <0.001, respectively). However, postoperative shoulder pain, abdominal pain, and arrhythmia in the AWL+LP group were less than those in SP group (P=0.01, 0.017, 0.005, respectively). There was no significant difference in operative time (106.54±27.80 vs. 107.38±24.78 min), blood loss [15 mL (interquartile range: 12.5 to 20 mL) vs.15 mL (interquartile range: 10 to 20 mL)], length of stay (4 vs. 4 d), the wound ecchymosis [2 (1.87%) vs. 3 (2.80%)] and rates of recurrence [8 (7.48%) vs. 5 (4.67%)] between AWL+LP group and SP group.

CONCLUSION

AWL+LP resulted in comparable perioperative and prognostic outcomes with less impact on changes in cardiorespiratory function compared with SP approaches of laparoscopic fundoplication for GERD.

Consensus on safe implementation of vaginal natural orifice transluminal endoscopic surgery (vNOTES)

STUDY OBJECTIVE

The first ever report of vaginal natural orifice transluminal endoscopic surgery (vNOTES) for benign gynaecological was reported in 2012. There has been an exponential uptake of the number of surgeons performing such procedures worldwide with no official guidance to ensure the safe implementation of this technique into gynaecological practice due its recency. The objective of this study is to report an international consensus-based statement to help guide a basis for adopting vNOTES into clinical practice.

STUDY DESIGN

The consensus-based statement was developed amongst 39 international experts using the Delphi methodology over three successive rounds. Consensus was pre-defined as an agreement of 80% or more by the experts. Consensus sought over eight key concepts pertaining to vNOTES including patient selection, perioperative management, surgical technique, instruments, anatomy, training, registries and trials and definition of the surgical technique. Recommendations from an expert anaesthetist and urogynaecologist were also sought to give a broader perspective with respect to the implementation of vNOTES.

RESULTS

Fifty nine international surgeons were invited to participate and 39 (66%) agreed to participate based on being involved in a minimum of 20 vNOTES procedures. They were from 13 countries across 5 continents (Europe, North America, South America, Australia and Asia). Participation was 100% on all three rounds. Overall, consensus was reached in 50 of the 56 questions (89%) with the remaining 6 questions where consensus was not reached pertaining to the domain of patient selection.

CONCLUSION

An international expert based vNOTES statement is presented here to help guide adoption of vNOTES based on the experience of early adopters. Consensus was achieved on most components of this consensus statement. Given the recency of this technique, until high-level evidence becomes available, this statement provides an appropriate guidance to the safe implementation of vNOTES into gynaecological practice.

Can We Routinely Employ the Use of Low-Pressure Gynaecological Laparoscopy? A Systematic Review

Clinicians have learnt valuable lessons throughout the COV-SARS-2 pandemic, many of which have produced solutions that we aim to continue to implement within the foreseeable future. Optimising patients’ surgical pathways to reduce the length of stay and complications is an area of particular importance, both for maximal utilisation of available resources and for reduction of the exposure of inpatient and elective patients to an increased risk of infection within healthcare facilities.

The aim of this review was to investigate the possible implications of using low-pressure laparoscopic gynaecological surgery versus standard- or high-pressure pneumoperitoneum surgeries. The primary outcome was postoperative pain, with secondary outcomes including duration of surgery, length of inpatient stay and rate of complications.

MEDLINE, Embase and Cochrane CENTRAL were searched from inception to December 2020. We searched for published randomised control trials comparing low-pressure laparoscopic surgery (≤8 mmHg) to at least one additional standardised pneumoperitoneum pressure (≥12 mmHg and/or ≥15 mmHg). A total of 203 studies were reviewed, five of which were included in this analysis. Studies comparing low-pressure laparoscopic surgery against gasless abdominal cavities were excluded.

The meta-analysis of the results was pooled and calculated within RevMan 5.0 software (Cochrane, London, England). Studies using a visual analogue scale (1-10) to compare low versus standard pneumoperitoneum pressures did not display a significant diminution of postoperative pain at ≤ 6 or 24 hours: -0.30 [95% CI -0.63, 0.03] and -0.66 [95% CI -1.35, 0.02], respectively. Studies additionally demonstrated worse visualisation of the surgical field within the low-pressure group (risk ratio 10.31; 95% CI, 1.29-82.38 I² = 0%). Studies measuring postoperative pain using a numerical rating scale displayed significant pain reduction at all hours measured (p ≤ 0.01). The rate of intraoperative complications was 1% for all groups measured. Cumulative analysis of the duration of surgery did not differ significantly between groups (p = 0.99).

The pandemic has revealed new issues that must be addressed by clinicians to promote the safety of patients and the efficiency of inpatient stay. This review has paved the way for new possibilities and innovative approaches to address the issue of optimising patient surgical pathways; however, at present, we cannot give a firm justification for the use of low-pressure gynaecological laparoscopy. Reasons for this include the minimal reduction in pain scores between low, standard and high pneumoperitoneum pressures, leading to a mixture of statistically significant results, as well as a reduction in the visualisation of the surgical field and the small population sizes in the reviewed papers. Additional research is required to further explore the potential clinical benefits of gynaecological laparoscopy to ensure its effective ambulatory use within mainstream surgical operations.

Paradoxical carbon dioxide embolism during laparoscopic surgery without intracardiac right-to-left shunt: two case reports and a brief review of the literature

We herein report two cases of paradoxical carbon dioxide (CO₂) embolism during laparoscopic nephrectomy and hepatic left lateral lobectomy without evidence of a right-to-left shunt or obvious rupture of blood vessels. Transesophageal echocardiography detected paradoxical CO₂ embolism before the end-tidal CO₂ partial pressure (P_ETCO₂) dropped from baseline. The pneumoperitoneum was reduced or stopped immediately after detection of the embolism. One patient developed a postoperative epileptiform seizure. In the other patient, many gas bubbles were drawn out from the central venous line. We speculate that rapid introduction of pneumoperitoneum pushed a large amount of CO₂ into the abdominal blood vessels, exceeding the gas exchange capacity of the lung and causing CO₂ bubble formation in the left-side cardiac system. These two cases indicate that intraoperative transesophageal echocardiography can reduce the influence of CO₂ embolism during laparoscopic tumor surgery by early diagnosis of the embolism and provide helpful information to establish a list of differential diagnoses of postoperative complications.

Effect of Deep Versus Moderate Neuromuscular Block on Pain After Laparoscopic Colorectal Surgery: A Randomized Clinical Trial

BACKGROUND

Anesthesia with deep neuromuscular block for laparoscopic surgery may result in less postoperative pain with lower intra-abdominal pressure. However, results in the existing literature are controversial.

OBJECTIVE

The study aimed to evaluate the effect of deep neuromuscular block on postoperative pain at rest and during coughing after laparoscopic colorectal surgery.

DESIGN

The design is a parallel-group, randomized clinical trial.

SETTINGS

The study was conducted at a tertiary care center.

PATIENTS

Patients undergoing laparoscopic resection of colorectal tumors were included.

INTERVENTIONS

Patients were randomly assigned to either a deep (posttetanic count 1 to 2) or moderate (train-of-four 1 to 2) neuromuscular group.

MAIN OUTCOME MEASURES

The coprimary efficacy outcomes were numeric rating scale scores of the postoperative pain at rest and during coughing after surgery.

RESULTS

Pain was lower in the deep neuromuscular block group at rest and during coughing at 1, 6, 24, and 48 hours after surgery (median difference of 2 points and 1 point at 1 h; p < 0.001 at each time point). The deep neuromuscular block group displayed a significantly lower number of bolus attempts by the patient (4 in the deep group vs 9 in the moderate group; p < 0.001) and boluses delivered (4 in the deep group vs 9 in the moderate group; p < 0.001) on postoperative day 1. The number of rescue analgesics was lower in the deep group on postoperative day 2 (p < 0.001). The deep neuromuscular block group showed a lower frequency of postoperative nausea and vomiting (p = 0.02) and lower intraoperative intra-abdominal pressure (p < 0.001).

LIMITATIONS

This was a single-center study.

CONCLUSIONS

Deep neuromuscular block resulted in better pain relief and lower opioid consumption and use of rescue analgesics after laparoscopic colorectal surgery. Deep neuromuscular block was associated with less postoperative nausea and vomiting and facilitated the use of lower intra-abdominal pressure in laparoscopic surgery. See Video Abstract at http://links.lww.com/DCR/B458.

EFECTO DEL BLOQUEO NEUROMUSCULAR PROFUNDO VERSUS MODERADO EN EL DOLOR, DESPUS DE LA CIRUGA COLORRECTAL LAPAROSCPICA UN ENSAYO CLNICO ALEATORIZADO

ANTECEDENTES:La anestesia con bloqueo neuromuscular profunda para cirugía laparoscópica, puede resultar con menor dolor postoperatorio y con menos presión intraabdominal. Sin embargo, los resultados en la literatura existente son controvertidos.OBJETIVO:El objetivo del estudio, fue evaluar el efecto del bloqueo neuromuscular profundo en dolor postoperatorio de reposo y con la tos, después de cirugía colorrectal laparoscópica.DISEÑO:Ensayo clínico aleatorizado de grupos paralelos.AJUSTE:El estudio se realizó en un centro de atención terciaria.PACIENTES:Se incluyeron pacientes sometidos a resección laparoscópica de tumores colorrectales.INTERVENCIONES:Los pacientes fueron aleatorizados a un grupo neuromuscular profundo (recuento posttetánico 1 a 2) o moderado (tren de cuatro 1 a 2).PRINCIPALES MEDIDAS DE RESULTADO:Los resultados coprimarios de eficacia, fueron las puntuaciones numéricas en la escala de calificación del dolor postoperatorio en reposo y durante la tos, después de la cirugía.RESULTADOS:El dolor fue menor en el grupo de bloqueo neuromuscular profundo en reposo y durante la tos, en 1, 6, 24, 48 horas después de la cirugía, (diferencia de mediana de 2 puntos y 1 punto respectivamente en 1 hora; p <0,001 en cada punto de tiempo). El grupo de bloqueo neuromuscular profundo, mostró un número significativamente menor de intentos de bolo por parte del paciente, (4 en el grupo profundo versus 9 del grupo moderado, p <0,001) y de bolos administrados (4 en el grupo profundo versus 9 en el grupo moderado, p <0,001) en el primer día postoperatorio. El número de analgésicos de rescate, fue menor en el grupo profundo en el segundo día postoperatorio (p <0,001). El grupo de bloqueo neuromuscular profundo, mostró una menor frecuencia de náuseas y vómitos postoperatorios (p = 0,02) y una menor presión intraoperatoria e intraabdominal (p <0,001).LIMITACIONES:Este estudio fue un estudio de un solo centro.CONCLUSIONES:El bloqueo neuromuscular profundo, resultó en mayor alivio del dolor y menor consumo de opioides y uso de analgésicos de rescate, después de la cirugía colorrectal laparoscópica. El bloqueo neuromuscular profundo, se asoció con menos náuseas y vómitos posoperatorios y facilitó el uso de una presión intraabdominal más baja, en la cirugía laparoscópica. Consulte Video Resumen en http://links.lww.com/DCR/B458.

Low-pressure versus standard pressure laparoscopic colorectal surgery (PAROS trial): a phase III randomized controlled trial

TRIAL DESIGN

This is a phase III, double-blind, randomized, controlled trial.

METHODS

In this trial, patients with laparoscopic colectomy were assigned to either low pressure (LP: 7 mmHg) or standard pressure (SP: 12 mmHg) at a ratio of 1 : 1. The aim of this trial was to assess the impact of low-pressure pneumoperitoneum during laparoscopic colectomy on postoperative recovery. The primary endpoint was the duration of hospital stay. The main secondary endpoints were postoperative pain, consumption of analgesics and postoperative morbidity.

RESULTS

Some 138 patients were enrolled, of whom 11 were excluded and 127 were analysed: 62 with LP and 65 with SP. Duration of hospital stay (3 versus 4 days; P = 0.010), visual analog scale (0.5 versus 2.0; P = 0.008) and analgesic consumption (level II: 73 versus 88 per cent; P = 0.032; level III: 10 versus 23 per cent; P = 0.042) were lower with LP. Morbidity was not significantly different between the two groups (10 versus 17 per cent; P = 0.231).

CONCLUSION

Using low-pressure pneumoperitoneum in laparoscopic colonic resection improves postoperative recovery, shortening the duration of hospitalization and decreasing postoperative pain and analgesic consumption. This suggests that low pressure should become the standard of care for laparoscopic colectomy.

TRIAL REGISTRATION

NCT03813797.

Minimally invasive versus open radical resection surgery for hilar cholangiocarcinoma: Comparable outcomes associated with advantages of minimal invasiveness

Background

Minimally invasive surgery (MIS) provides a new approach for patients with hilar cholangiocarcinoma (HCCA). However, whether it can achieve similar outcomes to traditional open surgery (OS) remains controversial.

Methods

To assess the safety and feasibility of MIS for HCCA, a systematic review and meta-analysis was performed to compare the outcomes of MIS with OS. Seventeen outcomes were assessed.

Results

Nine studies involving 382 patients were included. MIS was comparable in blood transfusion rate, R0 resection rate, lymph nodes received, overall morbidity, severe morbidity (Clavien–Dindo classification > = 3), bile leakage rate, wound infection rate, intra-abdominal infection rate, days until oral feeding, 1-year overall survival, 2-year overall survival and postoperative mortality with OS. Although operation time was longer (mean difference (MD) = 93.51, 95% confidence interval (CI) = 64.10 to 122.91, P < 0.00001) and hospital cost (MD = 0.68, 95% CI = 0.03 to 1.33, P = 0.04) was higher in MIS, MIS was associated with advantages of minimal invasiveness, that was less blood loss (MD = -81.85, 95% CI = -92.09 to -71.62, P < 0.00001), less postoperative pain (MD = -1.21, 95% CI = -1.63 to -0.79, P < 0.00001), and shorter hospital stay (MD = -4.22, 95% CI = -5.65 to -2.80, P < 0.00001).

Conclusions

The safety and feasibility of MIS for HCCA is acceptable in selected patients. MIS is a remarkable alternative to OS for providing comparable outcomes associated with a benefit of minimal invasiveness and its application should be considered more.

Randomized Controlled Comparison of Valveless Trocar (AirSeal) vs Standard Insufflator with Ultralow Pneuomoperitoneum During Robotic Prostatectomy

Objective: To compare valveless insufflation (AirSeal^®) with a conventional insufflation system (CIS) during robotic prostatectomy (RP) and the ability to use ultralow pneumoperitoneum at 6 mm Hg with each system as well as comparison of physiologic outcomes and pain scores. Patients and Methods: We conducted a prospective study of 100 patients randomized to AirSeal or CIS during RP. The frequency of need for increasing pneumoperitoneum was assessed as well as arterial blood gases, respiratory/hemodynamic parameters, pain scores, and analgesic requirements. Quality of smoke evacuation and scope cleaning frequency were also measured. Results: All procedures were completed at 6 mm Hg without needing to increase pressures with either insufflator. There were no statistically significant differences in partial pressure of carbon dioxide (PaCO₂), partial pressure of oxygen (PaO₂), HCO₃, pH, carbon dioxide (CO₂) elimination, or end-tidal carbon dioxide pressure (EtCO₂) between groups. The AirSeal group had a lower maximum peritoneal pressure (7.9 vs 9.9 mm Hg, p < 0.001) but without differences in pain scores or analgesics. Surgeon-assessed smoke evacuation was poorer using CIS with more laparoscope cleanings in nonobese patients than with AirSeal (2.1 vs 3.0, p = 0.026). Conclusion: Valveless-trocar insufflation provided more stable pressure but without benefits in physiologic or pain parameters. Previously identified benefits may have been negated by being able to complete all procedures at ultralow pressure with either insufflator, although an expert bedside assistant moderating suction may have contributed to feasibility of maintaining low pressure with CIS. A randomized trial of 6 vs 15 mm Hg is currently underway. The ClinicalTrials.gov Identifier: NCT02114164.

Effects of deep neuromuscular block with low-pressure pneumoperitoneum on respiratory mechanics and biotrauma in a steep Trendelenburg position

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, at the end of PP, and 24 h after surgery. 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 (P_group*time = 0.036). The peak inspiratory, driving, and mean airway pressures were significantly higher in moderate NMB group than in deep NMB group at 15 min and 60 min after PP (P_group*time = 0.002, 0.003, and 0.048, respectively). In conclusion, 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.

Modeling intra-abdominal volume and respiratory driving pressure during pneumoperitoneum insufflation-a patient-level data meta-analysis

During pneumoperitoneum, intra-abdominal pressure (IAP) is usually kept at 12-14 mmHg. There is no clinical benefit in IAP increments if they do not increase intra-abdominal volume IAV. We aimed to estimate IAV (ΔIAV) and respiratory driving pressure changes (ΔP_RS) in relation to changes in IAP (ΔIAP). We carried out a patient-level meta-analysis of 204 adult patients with available data on IAV and ΔP_RS during pneumoperitoneum from three trials assessing the effect of IAP on postoperative recovery and airway pressure during laparoscopic surgery under general anesthesia. The primary endpoint was ΔIAV, and the secondary endpoint was ΔP_RS. The endpoints' response to ΔIAP was modeled using mixed multivariable Bayesian regression to estimate which mathematical function best fitted it. IAP values on the pressure-volume (PV) curve where the endpoint rate of change according to IAP decreased were identified. Abdomino-thoracic transmission (ATT) rate, that is, the rate ΔP_RS change to ΔIAP was also estimated. The best-fitting function was sigmoid logistic and linear for IAV and ΔP_RS response, respectively. Increments in IAV reached a plateau at 6.0 [95%CI 5.9-6.2] L. ΔIAV for each ΔIAP decreased at IAP ranging from 9.8 [95%CI 9.7-9.9] to 12.2 [12.0-12.3] mmHg. ATT rate was 0.65 [95%CI 0.62-0.68]. One mmHg of IAP raised ΔP_RS 0.88 cmH₂O. During pneumoperitoneum, IAP has a nonlinear relationship with IAV and a linear one with ΔP_RS. IAP should be set below the point where IAV gains diminish.NEW & NOTEWORTHY We found that intra-abdominal volume changes related to intra-abdominal pressure increase reached a plateau with diminishing gains in commonly used pneumoperitoneum pressure ranges. We also found a linear relationship between intra-abdominal pressure and respiratory driving pressure, a known marker of postoperative pulmonary complications.

[The first 50 robot-assisted donor nephrectomies : Lessons learned]

Hintergrund

Die minimal-invasive Donornephrektomie (DN) ist inzwischen operativer Standard, bezüglich der Rolle von roboterassistierten Verfahren gibt es bisher keinen Konsens.

Fragestellung

Die ersten 50 transperitonealen roboterassistierten Donornephrektomien (RDN) einer urologischen Universitätsklinik in Deutschland wurden retrospektiv ausgewertet.

Material und Methoden

Patientencharakteristika, intra- und postoperative Parameter wurden erfasst und die Nierenfunktion in einem 5‑jährigen Follow-up ausgewertet. Signifikante Prädiktoren für die Nierenfunktion bei Entlassung und ein Jahr postoperativ wurden in einem multivariablen Regressionsmodell bestimmt.

Ergebnisse

Die RDN hat exzellente Ergebnisse mit niedriger Komplikationsrate, kurzer warmer (WIZ) und kalter Ischämiezeit (KIZ) sowie geringem Blutverlust und kurzer Patientenverweildauer. Die Seite der Nierenentnahme hat hierauf keine Auswirkungen. Nach RDN sind etwa 50 % der Spender formal niereninsuffizient, was aber zumeist ohne Relevanz ist, weil sich die Nierenfunktion der Spender im Follow-up nicht weiter verschlechtert. Die postoperative Nierenfunktion lässt sich bei der RDN mithilfe der präoperativen eGFR (errechnete glomeruläre Filtrationsrate) und dem Spenderalter sehr gut vorhersagen.

Schlussfolgerungen

Die robotische DN stellt eine sehr gute Alternative zu anderen minimal-invasiven Operationsverfahren dar, die von Beginn an exzellente operative Ergebnisse ermöglicht.

Low-pressure Pneumoperitoneum in Laparoscopic Cholecystectomy: A Randomized Controlled Trial

BACKGROUND/PURPOSE

To compare the changes in hepatic enzymes and comfort level of the surgeon in low-pressure pneumoperitoneum laparoscopic cholecystectomy (LPPLC, 7 mm Hg) with that of normal pressure pneumoperitoneum laparoscopic cholecystectomy (NPPLC, 14 mm Hg).

METHODS

Eighty-two patients were randomly divided into 2 groups (LPPLC and NPPLC). Serum levels of bilirubin, serum glutamic-oxaloacetic transaminase, serum glutamic-pyruvic transaminase, alkaline phosphatase, and lactate dehydrogenase were measured before the operation, at the time of reversal from anesthesia, 24 hours after the operation, and on day 7. Serious adverse events, intra-operative complications, surgeon's comfort level of dissection, operative time, conversion rates to an open procedure, or normal pressure pneumoperitoneum were recorded.

RESULTS

Of the 41 patients randomized for LPPLC, 8 patients were converted to NPPLC due to difficulty in dissection and 1 converted to open in each group. There was statistically significant fall in mean serum bilirubin level in both the groups in the immediate postoperative period (P<0.05). Statistically significant increase in its level was observed after 24 hours in the NPPLC group only (P<0.05). Levels of mean serum serum glutamic-oxaloacetic transaminase, serum glutamic-pyruvic transaminase, and lactate dehydrogenase increased significantly (P<0.05) in immediate postoperative period and a further increase was observed after 24 hours (P<0.05) in the NPPLC group only. The comfort level of surgeon was found to be significantly better in the NPPLC group.

CONCLUSIONS

LPPLC is a safe procedure, especially in the hands of an experienced surgeon with clinically insignificant systemic effects. But the comfort level of surgeon is better in normal pressure when compared with low pressure. In patients with deranged hepatic functions undergoing advanced laparoscopic procedures, it is advisable to start the surgery with low-pressure pneumoperitoneum. Pressure may be escalated further as per the surgeon's comfort.

Clinical and Organizational Impact of the AIRSEAL® Insufflation System During Laparoscopic Surgery: A Systematic Review

Several low-impact laparoscopic strategies have been developed to improve the safety of pneumoperitoneum. We conducted a systematic review to establish the current evidence base for the use of the AIRSEAL^® insufflation device for low-pressure pneumoperitoneum in laparoscopic surgery. We searched the literature using several electronic databases, for studies with comparative design published in the English language from January 2010 to April 2020. The population of interest included patients with any type of health condition who underwent laparoscopic surgery using the AIRSEAL^® insufflation system or a standard CO₂ insufflator. Ten studies (four randomized clinical trials/six non-randomized clinical trials), that enrolled 1394 participants in total who underwent urology, gynaecology or abdominal surgeries, were included. Total complication rates were similar between groups. Only three studies evaluated the impact of the insufflation system on post-operative pain, and showed inconsistent benefit of AIRSEAL^® (significant decrease in pain in two studies, no difference in one). The same was observed in the two sole studies in which pain killers consumption was measured (significant decrease in morphine consumption 24 h after surgery in one study, no difference in the other). Operative duration was significantly shorter with AIRSEAL^® in three studies. For both post-operative room and total length of stay, there was no difference between groups. No studies reported economic outcomes. Current literature supports the feasibility of the AIRSEAL^® system during laparoscopic surgery but more studies are required to establish the added clinical benefit and to explore the preferences of physicians and patients.

Impact of anthropometric data on technical difficulty of laparoscopic liver of resections of segments 7 and 8: the CHALLENGE index

BACKGROUND

The high technical difficulty of using a laparoscopic approach to reach the posterosuperior liver segments is mainly associated with their poor accessibility. This study was performed to analyze correlations between anthropometric data and intraoperative outcomes.

STUDY DESIGN

All patients who underwent segmentectomy or wedge laparoscopic liver resection (LLR) of segments seven and/or eight from June 2012 to November 2019 were retrospectively analyzed. The exclusion criteria were intrahepatic cholangiocarcinoma, associated resection, multiple concomitant LLR, redo resection, and lack of preoperative imaging. Anthropometric data were correlated with intraoperative outcomes.

RESULTS

Forty-one patients (wedge resection, n = 32; segmentectomy, n = 9) were analyzed. A strong correlation was found between the craniocaudal liver diameter (CCliv) and liver volume (r = 0.655, p < 0.001). The anteroposterior liver diameter was moderately correlated with both the laterolateral abdominal diameter (LLabd) (r = 0.372, p = 0.008) and anteroposterior abdominal diameter (r = 0.371, p = 0.008). The body mass index (BMI) was not correlated with liver diameters. Women had a longer CCliv (p = 0.002) and shorter LLabd (p < 0.001) than men. The liver and abdominal measurements were combined to reduce this sex-related disparity. The CCliv/LLabd ratio (CHALLENGE index) was significantly correlated with the time of transection (r = 0.382, p = 0.037) and blood loss (r = 0.352, p = 0.029). The association between the CHALLENGE index and intraoperative blood loss was even stronger when considering only anatomical resection (r = 0.577, p = 0.048). A CHALLENGE index of > 0.4 (area under the curve, 0.757; p = 0.046) indicated a higher bleeding risk. The BMI predicted no intraoperative outcomes.

CONCLUSION

Anthropometric data rather than the BMI can help anticipate the difficulty of LLR of segments seven and eight.