Effects of depth of neuromuscular block on surgical operating conditions in women undergoing gynecologic laparoscopic surgery: a randomized clinical trial

Background: In recent years, the relationship between the advantages and disadvantages of a deep neuromuscular block (DNMB), compared to a moderate block (MNMB) in laparoscopic surgery, has been increasingly studied. Objective: Evaluate the effect of D-NMB compared to M-NMB in gynecological laparoscopic surgery. Methods: This was a parallel-group, double-blind, randomized clinical trial, conducted at a single center in Italy between February 2020 and July 2020. American Society of Anesthesiologist (ASA) I-II risk class patients scheduled for elective gynecological laparoscopic surgery were randomized into a 1:1 ratio to either experimental or control group. The first one included DNMB with a rocuronium bolus at the starting dose of 1.2 mg/kg and a maintenance dose (0.3-0.6 mg/kg/h). The second one included MNMB with a rocuronium bolus at the starting dose of 0.6 mg/kg, and a maintenance dose in boluses (0.15-0.25 mg/kg). The primary outcome was the intraoperative surgical condition assessed every 15 min by the surgeon as a 5-point scale. The secondary outcome was the time needed to discharge patients from post-anesthesia care unit (PACU). The tertiary outcome was the assessment of the intra-operative hemodynamic instability. A sample size of 50 patients was planned. Results: One hundred five patients were assessed for eligibility, 55 were excluded. Fifty patients met the inclusion criteria and were enrolled. The average score for the operative field was 4 for the D-NMB group and 3 for the M-NMB group (p value < 0.01). The length of stay in PACU was 13 min for the DNMB group and 22 min for the MNMB group (p value = 0.02). Conclusions: Deep neuromuscular block improves intraoperative surgical condition during gynecological laparoscopic surgery. Trial registration: clinicalTrials.gov NCT03441828.