Effect of an individualized versus standard pneumoperitoneum pressure strategy on postoperative recovery: a randomized clinical trial in laparoscopic colorectal surgery

Impact of low-pressure pneumoperitoneum and deep neuromuscular blockade on surgeon satisfaction and patient outcomes in laparoscopic cholecystectomy patients: A prospective randomised controlled study

INTRODUCTION

The impact of laparoscopic surgery on homeostatic systems necessitates careful consideration of intra-abdominal pressure (IAP) management. This study investigated the effects of low-pressure pneumoperitoneum with deep neuromuscular blockade (NMB) on surgeon satisfaction, haemodynamics and post-operative outcomes in laparoscopic cholecystectomy patients.

PATIENTS AND METHODS

The study design involves prospective randomised control. Ninety patients were assigned to low (7-10 mmHg, n = 45) or normal (12-16 mmHg, n = 45) IAP groups. Deep NMB, guided by train-of-four monitoring, was administered. This study evaluated surgical rating scale scores, haemodynamics and post-operative outcomes through a literature review. A computer programme (IBM, SPSS) was used for statistical analysis. Chi-square and Mann-Whitney U tests were used to analyse patients' IAP levels, additional NMB requirements, surgical rating scale scores and numerical rating scales. Patient demographics and other intraoperative and post-operative variables were analysed with Student's t -test and the Mann-Whitney U test. Values of P < 0.05 were considered to indicate statistical significance.

RESULTS

No significant demographic differences were observed. The low-pressure group exhibited lower post-operative pain ( P < 0.01) and reduced analgesia requirements ( P = 0.00). On analysis of the surgeon rating scale, no disparities were evident between the groups. NMB usage correlated with height and weight ( P < 0.01). Heart rate showed no intergroup differences. The MAP measured after 15 min was lower in Group L, and the difference was significant ( P = 0.023). The SAP measured after 30 min was lower in Group L, and the difference was significant ( P = 0.017). Blood gas values and surgical field visibility were unaffected by the IAP. The positive correlations between NMB, height and weight aligned with previous research.

CONCLUSION

This study highlights successful laparoscopic cholecystectomy under low IAP, deep NMB and favourable post-operative outcomes. Despite these limitations, the findings contribute to optimising laparoscopic surgical approaches.

Low vs. conventional intra-abdominal pressure in laparoscopic colorectal surgery: a prospective cohort study

PURPOSE

Low intraabdominal pressure (IAP) during laparoscopy is associated with improved post-operative outcomes across a variety of surgical specialties. A prospective cohort study was undertaken to assess post-operative outcomes in patients undergoing laparoscopic colorectal surgery (LCRS) with low (8mmHg) versus conventional (15mmHg) IAP.

METHODS

A prospective real-world observational study of patients undergoing LCRS in a single-centre, between June 2020 and June 2023 was performed. Operative procedures for diverse colonic pathology such as diverticular disease, inflammatory bowel disease (IBD), and colorectal cancers (CRC) were included. The evaluated primary outcomes were post-operative pain, return of gastrointestinal motility, and length of hospital stay. Secondary outcomes were the overall safety profile including intra- and post-operative complications and morbidity. Outcomes of interest were investigated using multivariate analysis.

RESULTS

A total of 120 patients were included of which 69 (57.5%) were male. Median age and BMI of the cohort was 67 years (51-75 years) and 27 kg/m2 (24-32 kg/m2), respectively. 61 (50.8%) patients were categorised as an ASA grade 3. Two (1.7%) patients had diverticular disease; 31 (25.9%) had IBD, and 87 (72.4%) were operated on for colonic malignancy. Low IAP (8mmHg) was used in 53 (44.2%) cases, whilst the remainder (55.8%) had IAP set at 15mmHg (conventional). Low-pressure surgery was associated with improved intraoperative lung compliance (p < 0.001) and peak inspiratory pressures up to 6 h (p < 0.001); reduced analgesic requirement (p ≤ 0.028), and decreased postoperative pain both at rest (p = 0.001) and on exertion (p < 0.001). Moreover, low IAP was associated with an earlier time to pass flatus postoperatively (p = 0.047) with no significant difference in length of hospital stay (p = 0.574). Additionally, no significant difference was observed between the groups for outcomes including median operating time (p = 0.089), conversion to open surgery (p = 0.056), overall complication rate (p = 0.102), and 90-day mortality (p = 0.381).

CONCLUSION

Low IAP use during LCRS is feasible with a comparable safety profile to conventional laparoscopy. Intra-operative respiratory physiology is improved with reduced postoperative pain and analgesic requirement, and earlier time to pass flatus. Future rationally designed; well-powered, randomised trials are needed to understand the benefits of low intra-peritoneal pressure during laparoscopic colorectal resections.

Impact of abdominal compliance on surgical stress and postoperative recovery in laparoscopic groin hernia repair: a retrospective cohort study

PURPOSE

The role of abdominal compliance in pneumoperitoneum is not fully understood. This study aimed to clarify the association between abdominal wall stretching tendency and surgical stress in laparoscopic groin hernia repair.

METHODS

We conducted a retrospective single-center cohort study, evaluating 51 patients who underwent elective transabdominal preperitoneal groin hernia repair. Abdominal compliance was assessed using the abdominal compliance index (ACI; insufflated intra-abdominal volume [L] / body surface area [m²]) at 8 mmHg intra-abdominal pressure. Surgical stress and recovery were evaluated with patient-reported outcome measures (PROMs), including QOR-15 and pain visual analog scale (VAS) scores. Associations between ACI, PROMs, and clinical outcomes were analyzed.

RESULTS

The median ACI was 1.229 L/m² (0.369-2.091). Eleven patients (21.6%) above the 75th percentile cutoff (1.576 L/m²) were categorized as high ACI. While body constitution was similar between groups, the high ACI group had significantly greater insufflated intra-abdominal volume (2.88 L vs. 1.89 L, P < 0.0001). Pre-operative QOR-15 scores were similar. However, on postoperative day 1, the high ACI group had significantly lower QOR-15 scores (90.2 vs. 110.1, P = 0.017), with subcategory analysis showing reduced physical well-being. Multivariate analysis indicated that high ACI was a significant predictor of poorer QOR. The high ACI group also reported higher, though not statistically significant, postoperative pain.

CONCLUSION

Abdominal walls with greater elasticity, which stretch excessively under pneumoperitoneum, were more susceptible to surgical stress. Further studies are warranted to evaluate the efficacy of tailored pneumoperitoneum pressure adjustment based on abdominal compliance to mitigate surgical stress.

Surgical conditions in experimental laparoscopy: effects of pressure, neuromuscular blockade, and pre-stretching on workspace volume

BACKGROUND

Establishing a pneumoperitoneum for laparoscopy is common surgical practice, with the goal to create an optimal surgical workspace within the abdominal cavity while minimizing insufflation pressure. Individualized strategies, based on neuromuscular blockade (NMB), pre-stretching routines, and personalized intra-abdominal pressure (IAP) to enhance surgical conditions are strategies to improve surgical workspace. However, the specific impact of each factor remains uncertain. This study explores the effects and side-effects of modifying intra-abdominal volume (IAV) through moderate and complete NMB in a porcine laparoscopy model.

METHODS

Thirty female Landrace pigs were randomly assigned to groups with complete NMB, regular NMB and a control group. Varying IAP levels were applied, and IAV was measured using CT scans. The study evaluated the maximum attainable IAV (Vmax), the pressure at which the cavity opens (p0), and the ease of expansion (λexp). Cardiorespiratory parameters, including peak inspiratory pressure (PIP), mean arterial pressure (MAP), heart rate (HR), and cardiac output (CO), were continuously recorded to evaluate side-effects.

RESULTS

There were no significant weight differences between NMB groups (median 21.1 kg). Observed volumes ranged from 0 to 4.7 L, with a mean Vmax of 3.82 L, mean p0 of 1.23 mmHg, and mean λexp of 0.13 hPa-1. NMB depth did not significantly affect these parameters. HR was significantly increased in the complete NMB group, while PIP, MAP, and CO remained unaffected. Repeated insufflation positively impacted Vmax; ease of opening; and expanding the cavity.

CONCLUSION

In this porcine model, the depth of NMB does not alter abdominal mechanics or increase the surgical workspace. Cardiorespiratory changes are more related to insufflation pressure and frequency rather than NMB depth. Future studies should compensate for the positive effect of repeated insufflation on abdominal mechanics and surgical conditions.

Low pneumoperitoneum pressure on venous thromboembolism in laparoscopic colorectal cancer surgery: A randomized controlled study

INTRODUCTION

Venous thromboembolism (VTE) poses a significant risk in colorectal cancer surgeries due to hypercoagulability and the anatomical challenges of the pelvic cavity. With the advancement of minimally invasive techniques, intraoperative strategies for preventing VTE may prove to be effective. This study explores the effects of intraoperative pneumoperitoneum pressures on VTE incidence following colorectal cancer surgeries.

METHODS

This single center parallel randomized controlled double-blind, trial involved 302 patients undergoing elective laparoscopic or robotic colorectal surgery. Patients were randomized to either a standard pneumoperitoneum pressure group (SP: 15 mmHg) or a low-pressure group (LP: 10 mmHg). Primary outcomes measured were the incidence of VTE, including symptomatic and asymptomatic DVT and PE. Secondary outcomes included postoperative D-dimer levels, surgery duration, blood loss, surgeon satisfaction, and oncological quality.

RESULTS

Out of 302 randomized patients, 275 were evaluable post exclusions, with 138 in the SP group and 137 in the LP group. The incidence of VTE was 10.9 % in the SP and 13.9 % in the LP group, with no significant difference between the two (P = 0.450). Secondary outcomes such as D-dimer levels, surgery duration, and blood loss showed no significant differences between two groups. Surgeon satisfaction and oncological outcomes were similarly comparable.

CONCLUSIONS

The trial demonstrated no significant difference in the incidence of VTE between standard and low pneumoperitoneum pressures. This suggests that lower pressures may not necessarily provide a benefit in reducing postoperative VTE in colorectal cancer surgeries.

Low-pressure versus standard-pressure pneumoperitoneum in minimally invasive colorectal surgery: a systematic review, meta-analysis, and meta-regression analysis

BACKGROUND

We aimed to assess the efficacy and safety of low-pressure pneumoperitoneum (LPP) in minimally invasive colorectal surgery.

METHODS

A PRISMA-compliant systematic review/meta-analysis was conducted, searching PubMed, Scopus, Google Scholar, and clinicaltrials.gov for randomized-controlled trials assessing outcomes of LPP vs standard-pressure pneumoperitoneum (SPP) in colorectal surgery. Efficacy outcomes [pain score in post-anesthesia care unit (PACU), pain score postoperative day 1 (POD1), operative time, and hospital stay] and safety outcomes (blood loss and postoperative complications) were analyzed. Risk of bias2 tool assessed bias risk. The certainty of evidence was graded using GRADE.

RESULTS

Four studies included 537 patients (male 59.8%). LPP was undertaken in 280 (52.1%) patients and associated with lower pain scores in PACU [weighted mean difference: -1.06, 95% confidence interval (CI): -1.65 to -0.47, P = 0.004, I 2  = 0%] and POD1 (weighted mean difference: -0.49, 95% CI: -0.91 to -0.07, P = 0.024, I 2  = 0%). Meta-regression showed that age [standard error (SE): 0.036, P < 0.001], male sex (SE: 0.006, P < 0.001), and operative time (SE: 0.002, P = 0.027) were significantly associated with increased complications with LPP. In addition, 5.9%-14.5% of surgeons using LLP requested pressure increases to equal the SPP group. The grade of evidence was high for pain score in PACU and on POD1 postoperative complications and major complications, and blood loss, moderate for operative time, low for intraoperative complications, and very low for length of stay.

CONCLUSIONS

LPP was associated with lower pain scores in PACU and on POD1 with similar operative times, length of stay, and safety profile compared with SPP in colorectal surgery. Although LPP was not associated with increased complications, older patients, males, patients undergoing laparoscopic surgery, and those with longer operative times may be at risk of increased complications.

Comparison of low versus high (standard) intraabdominal pressure during laparoscopic colorectal surgery: systematic review and meta-analysis

BACKGROUND

To evaluate outcomes of low with high intraabdominal pressure during laparoscopic colorectal resection surgery.

METHODS

A systematic search of multiple electronic data sources was conducted, and all studies comparing low with high (standard) intraabdominal pressures were included. Our primary outcomes were post-operative ileus occurrence and return of bowel movement/flatus. The evaluated secondary outcomes included: total operative time, post-operative haemorrhage, anastomotic leak, pneumonia, surgical site infection, overall post-operative complications (categorised by Clavien-Dindo grading), and length of hospital stay. Revman 5.4 was used for data analysis.

RESULTS

Six randomised controlled trials (RCTs) and one observational study with a total of 771 patients (370 surgery at low intraabdominal pressure and 401 at high pressures) were included. There was no statistically significant difference in all the measured outcomes; post-operative ileus [OR 0.80; CI (0.42, 1.52), P = 0.50], time-to-pass flatus [OR -4.31; CI (-12.12, 3.50), P = 0.28], total operative time [OR 0.40; CI (-10.19, 11.00), P = 0.94], post-operative haemorrhage [OR 1.51; CI (0.41, 5.58, P = 0.53], anastomotic leak [OR 1.14; CI (0.26, 4.91), P = 0.86], pneumonia [OR 1.15; CI (0.22, 6.09), P = 0.87], SSI [OR 0.69; CI (0.19, 2.47), P = 0.57], overall post-operative complications [OR 0.82; CI (0.52, 1.30), P = 0.40], Clavien-Dindo grade ≥ 3 [OR 1.27; CI (0.59, 2.77), P = 0.54], and length of hospital stay [OR -0.68; CI (-1.61, 0.24), P = 0.15].

CONCLUSION

Low intraabdominal pressure is safe and feasible approach to laparoscopic colorectal resection surgery with non-inferior outcomes to standard or high pressures. More robust and well-powered RCTs are needed to consolidate the potential benefits of low over high pressure intra-abdominal surgery.

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.

Low-impact laparoscopy in colorectal resection-A multicentric randomised trial comparing low-pressure pneumoperitoneum plus microsurgery versus low-pressure pneumoperitoneum alone: The PAROS II trial

INTRODUCTION

Low-pressure pneumoperitoneum (LLP) in laparoscopy colorectal surgery (CS) has resulted in reduced hospital stay and lower analgesic consumption. Microsurgery (MS) in CS is a technique that has a significant impact with respect to postoperative pain. The combination of MS plus LLP, known as low-impact laparoscopy (LIL), has never been applied in CS. Therefore, this trial will assess the efficacy of LLP plus MS versus LLP alone in terms of decreasing postoperative pain 24 h after surgery, without taking opioids.

METHOD

PAROS II will be a prospective, multicentre, outcome assessor-blinded, randomised controlled phase III clinical trial that compares LLP plus MS versus LLP alone in patients undergoing laparoscopic surgery for colonic or upper rectal cancer or benign pathology. The primary outcome will be the number of patients with postoperative pain 24 h after the surgery, as defined by a visual analogue scale rating ≤3 and without taking opioids. Overall, PAROS II aims to recruit 148 patients for 50% of patients to reach the primary outcome in the LLP plus MS arm, with 80% power and an 5% alpha risk.

CONCLUSION

The PAROS II trial will be the first phase III trial to investigate the impact of LIL, including LLP plus MS, in laparoscopic CS. The results may improve the postoperative recovery experience and decrease opioid consumption after laparoscopic CS.

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.

An Individualized Low-Pneumoperitoneum-Pressure Strategy May Prevent a Reduction in Liver Perfusion during Colorectal Laparoscopic Surgery

High intra-abdominal pressure (IAP) during laparoscopic surgery is associated with reduced splanchnic blood flow. It is uncertain whether a low IAP prevents this reduction. We assessed the effect of an individualized low-pneumoperitoneum-pressure strategy on liver perfusion. This was a single-center substudy of the multicenter 'Individualized Pneumoperitoneum Pressure in Colorectal Laparoscopic Surgery versus Standard Therapy II study' (IPPCollapse-II), a randomized clinical trial in which patients received an individualized low-pneumoperitoneum strategy (IPP) or a standard pneumoperitoneum strategy (SPP). Liver perfusion was indirectly assessed by the indocyanine green plasma disappearance rate (ICG-PDR) and the secondary endpoint was ICG retention rate after 15 min (R15) using pulse spectrophotometry. Multivariable beta regression was used to assess the association between group assignment and ICG-PDR and ICG-R15. All 29 patients from the participating center were included. Median IAP was 8 (25th-75th percentile: 8-10) versus 12 (12,12) mmHg, in IPP and SPP patients, respectively (p < 0.001). ICG-PDR was higher (OR 1.42, 95%-CI 1.10-1.82; p = 0.006) and PDR-R15 was lower in IPP patients compared with SPP patients (OR 0.46, 95%-CI 0.29-0.73; p = 0.001). During laparoscopic colorectal surgery, an individualized low pneumoperitoneum may prevent a reduction in liver perfusion.

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.

A novel method for monitoring abdominal compliance to optimize insufflation pressure during laparoscopy

BACKGROUND

Abdominal compliance describes the ease of expansion of the abdominal cavity. Several studies highlighted the importance of monitoring abdominal compliance (Cab) during the creation of laparoscopic workspace to individualize the insufflation pressure. The lack of validated clinical monitoring tools for abdominal compliance prevents accurate tailoring of insufflation pressure. Oscillometry, also known as the forced oscillation technique (FOT), is currently used to measure respiratory mechanics and has the potential to be adapted for monitoring abdominal compliance. This study aimed to define, develop and evaluate a novel approach which can monitor abdominal compliance during laparoscopy using endoscopic oscillometry.

MATERIALS AND METHODS

Endoscopic oscillometry was evaluated in a porcine model for laparoscopy. A custom-built insufflator was developed for applying an oscillatory pressure signal superimposed onto a mean intra-abdominal pressure. This insufflator was used to measure the abdominal compliance at insufflation pressures ranging from 5 to 20 hPa (3.75 to 15 mmHg). The measurements were compared to the static abdominal compliance, which was measured simultaneously with computed tomography imaging.

RESULTS

Endoscopic oscillometry recordings and CT images were obtained in 10 subjects, resulting in 76 measurement pairs for analysis. The measured dynamic Cab ranged between 0.0216 and 0.261 L/hPa while the static Cab based on the CT imaging ranged between 0.0318 and 0.364 L/hPa. The correlation showed a polynomial relation and the adjusted R-squared was 97.1%.

CONCLUSIONS

Endoscopic oscillometry can be used to monitor changes in abdominal compliance during laparoscopic surgery, which was demonstrated in this study with a comparison with CT imaging in a porcine laparoscopy model. Use of this technology to personalize the insufflation pressure could reduce the risk of applying excessive pressure and limit the drawbacks of insufflation.

Comparison of the outcomes of hemorrhoidectomy and PPH in the treatment of grades III and IV hemorrhoids

ABSTRACT

To investigate the clinical effect and outcome of traditional hemorrhoidectomy and procedures for prolapse and hemorrhoid (PPH) for the treatment of grades III and IV hemorrhoids.We retrospectively reviewed 1003 grades III and IV hemorrhoid patients who presented to our hospital. A total of 585 patients underwent PPH, and 418 patients underwent hemorrhoidectomy. The outcomes were 1-year recurrence, postoperative complications, surgery-related complications, and indicators.No significant difference between the 2 treatment groups regarding patient demographics. All patients underwent more than 12months of postoperative follow-up. No significant difference between the 2 treatment groups in 1-year recurrence. PPH can markedly improve anal pain, postoperative bleeding, difficult urination, and postoperative resting anal pressure. The operative blood loss, operative time, wound healing time, and wound infection rates were decreased significantly in the PPH group compared with the traditional hemorrhoidectomy group.Our data suggest that PPH is useful and safe for grades III and IV hemorrhoids. It can reduce postoperative and surgery-related complications. However, this was a single-hospital retrospective study. Therefore, well-designed, multicenter, randomized controlled trials are needed to evaluate the value of PPH for grades III and IV hemorrhoids.

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.

Deep Neuromuscular Blockade Combined with Low Pneumoperitoneum Pressure for Nociceptive Recovery After Major Laparoscopic Gastrointestinal Surgery: Study Protocol for a Randomized Controlled Trial

Purpose

Patients undergoing major laparoscopic surgery often experience significant pain and postoperative nausea and vomiting (PONV). Deep neuromuscular block (NMB) improves surgical conditions and facilitates the application of low intra-abdominal pressure (IAP), which may be beneficial for these patients. This study is designed to determine the effects of deep NMB combined with low IAP, as compared to moderate NMB combined with standard IAP, on patients' nociceptive recovery after major laparoscopic gastrointestinal surgery.

Study Design and Methods

This single-center randomized controlled trial will include 220 patients scheduled for major laparoscopic gastrointestinal surgery (lasts for ≥ 90 minutes). Patients will be randomly assigned, with a 1:1 ratio, into a deep NMB + low IAP group (train of four = 0, post-tetanic count = 1-3, IAP = 8 mmHg) and a moderate NMB + standard IAP group (train of four = 1-3, IAP = 12 mmHg). If the surgical workspace is inadequate, the surgeons can request a step increase of 1 mmHg in IAP during 3-min intervals. The upper limit of IAP will be set at 15 mmHg. Postoperative recovery will be assessed using the postoperative quality recovery scale (PQRS). The primary outcome of this trial is the PQRS nociceptive recovery (including pain and PONV) at postoperative day (POD) 1. The secondary outcomes include recovery in other PQRS domains at POD 1, and recovery in all PQRS domains in a post-anesthesia care unit, at POD 3 in the surgical wards, at hospital discharge, and at postoperative 30 days. For the sample size estimation, 110 patients in each group (220 in total) would be needed to detect an absolute increase rate of 20% in the PQRS nociceptive domain in the deep NMB + low IAP group at POD 1.

Discussion

This study investigates the effects of deep NMB combined with low IAP on postoperative PQRS nociceptive recovery in patients undergoing major laparoscopic gastrointestinal surgery. We expect that this deep NMB + low IAP strategy would improve postoperative pain and PONV following major laparoscopic gastrointestinal surgery.

The "Dark Side" of Pneumoperitoneum and Laparoscopy

Laparoscopic surgery has been one of the most common procedures for abdominal surgery at pediatric age during the last few decades as it has several advantages compared to laparotomy, such as shorter hospital stays, less pain, and better cosmetic results. However, it is associated with both local and systemic modifications. Recent evidence demonstrated that carbon dioxide pneumoperitoneum might be modulated in terms of pressure, duration, temperature, and humidity to mitigate and modulate these changes. The aim of this study is to review the current knowledge about animal and human models investigating pneumoperitoneum-related biological and histological impairment. In particular, pneumoperitoneum is associated with local and systemic inflammation, acidosis, oxidative stress, mesothelium lining abnormalities, and adhesion development. Animal studies reported that an increase in pressure and time and a decrease in humidity and temperature might enhance the rate of comorbidities. However, to date, few studies were conducted on humans; therefore, this research field should be further investigated to confirm in experimental models and humans how to improve laparoscopic procedures in the spirit of minimally invasive surgeries.

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.