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.