eP432 - Sugammadex or Cholinesterase Inhibitors with Standard or Low-Pressure Pneumoperitoneum for Preventing Complications in Minimally Invasive Colorectal Surgery: A Systematic Review

Purpose/Background: Sugammadex is a selective neuromuscular blockade (NMB) reversal agent that safely and rapidly reverses deep NMB following surgery. This rapid action enables deep NMB that allows for abdominal insufflation at low pressures without compromising the view of the surgical field or operability. Low-pressure pneumoperitoneum is also associated with improved perfusion to the parietal peritoneum and reduced risk of hypoxia-reperfusion injury during minimally invasive surgery. This study aims to determine which combination of NMB reversal agent and pneumoperitoneal pressure protocol leads to the most favourable outcomes in minimally invasive colorectal surgery.Methods/Interventions: A search was performed in five electronic databases. Patients from eligible studies, including adult individuals (≥ 18 years old) scheduled to undergo elective minimally invasive colorectal surgery with a primary colorectal anastomosis, were included in this review. Studies were eligible for inclusion if they compared the use of either acetylcholinesterase inhibitors (neostigmine or pyridostigmine), or sugammadex, in combination with either standard (SPP, defined as ≥ 12 mmHg intra-abdominal insufflation pressure) or low-pressure pneumoperitoneum (LPP, < 12 mmHg intra-abdominal insufflation pressure) during elective minimally invasive colorectal surgery, and reported on one of the pre-specified outcomes (Table). Identification of relevant citations proceeded in two phases: [1] title and abstract screening and [2] review of full-text publications. Screening of citations and risk of bias assessment was performed in duplicate by two reviewers independently. The main outcome measures for this systematic review were length of stay, operative time, time spent in the recovery room, and incidence of overall postoperative complications, pulmonary complications, and ileus. Risk of bias (RoB) was assessed using RoB 2.0 for randomized trials and ROBINS-I for observational studies.Results/Outcomes: The systematic search yielded 7963 citations, of which 57 underwent full-text review and eight were included for qualitative analysis. Of the included studies, six were randomized controlled trials (RCTs), and two were observational studies (retrospective cohort study design). There were three studies that compared LPP versus SPP using sugammadex reversal, two studies comparing LPP with sugammadex reversal versus SPP with acetylcholinesterase inhibitor reversal, and three studies comparing sugammadex versus acetylcholinesterase inhibitor in SPP (Table). Six studies quantitatively confirmed adequate NMB reversal. Risk of bias assessment reported low RoB for RCTs, and moderate RoB for observational studies. All studies had specific primary outcomes for their study, including the number of intra-operative abdominal pressure increases, quality of recovery scale scores, time to return of bowel function, and postoperative pain scores. Among the main clinical outcome measures for this review, there were no significant differences found in the included studies, and many were not reported (Table).Conclusion/

Discussion: This study summarizes the literature that has compared different combinations of NMB reversal agents with pneumoperitoneal pressures in minimally invasive colorectal surgery. There does not appear to be a significant benefit to SPP or LPP, or either reversal agent, likely because of adequate NMB monitoring. This work will inform subsequent network meta-analysis and cost-effectiveness studies of these interventions."Table. Completeness of Pre-Specified Clinical Outcomes Reported in Included Studies

ACHase = Acetylcholinesterase; LPP = Low Pressure Peritoneum; NS = Not Statistically Significant; NR = Not Reported;
PACU = Post-Anesthesia Care Unit; SPP = Standard Pressure Peritoneum
* = Retrospective study design
Figure 1. PRISMA Flow Diagram of Included Studies

Figure 2. Risk of Bias of Randomized Controlled Included Trials as per Cochrane RoB 2.0 Tool

Figure 3. Risk of Bias of Non-Randomized Studies as per ROBINS-I Tool
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