Incidence of postoperative residual neuromuscular blockade after general anesthesia: a prospective, multicenter, anesthetist-blind, observational study

Abstract

Objective: Evidences demonstrate that postoperative residual neuromuscular blockade (rNMB) is a primary and frequent anesthetic risk factor for postoperative complications. This study was designed to mitigate the paucity of data regarding the occurrence and degree of rNMB in a real-life setting.

Methods: This prospective, multicenter, anesthetist-blind, observational study enrolled 1571 Chinese adults undergoing elective open or laparoscopic abdominal surgery lasting ≤4 hours from 32 hospitals across China. The patients received anesthesia in accordance with routine practice at the study site. Neuromuscular blockade (NMB) was monitored using acceleromyography, with rNMB defined as a train-of-four (TOF) ratio <0.9.

Results: The patients' mean age was 46 years and 71% were female. The procedures included laparoscopic (67%), open abdominal (31%), and laparoscopic to open abdominal (2%). NMB was reversed with neostigmine in 78% of patients. The overall incidence of rNMB at extubation was 57.8%, and the proportions of participant with TOF ratios <0.6, 0.6-0.7, 0.7-0.8, 0.8-0.9 were 22.9%, 6.9%, 11.1% and 16.9%, respectively, immediately prior to endotracheal extubation. Age <45 years (OR = 0.630, 95% CI = 0.496-0.801, p = 0.002), use of one neuromuscular blocking agent (NMBA) (OR = 0.387, 95% CI = 0.243-0.618, p < 0.0001), time from neostigmine administration to endotracheal extubation ≥10 min (OR = 0.513, 95% CI = 0.400-0.658, p < 0.0001) and time from last NMBA administration to endotracheal extubation ≥60 min (OR = 0.902, 95% CI = 0.801-0.989, p = 0411) were correlated with non-rNMB at the time of extubation.

Conclusions: This observational study demonstrated that the overall incidence of rNMB at the time of endotracheal extubation was high in Chinese patients undergoing abdominal procedures, which necessitates appropriate management in current real-life practice.

Clinical trial registry number: NCT01871064.

Keywords: General anesthesia; Observational study; Residual neuromuscular blockade; Train-of-four monitoring.