Effect of Neuromuscular Blockade on Intraoperative Respiratory Mechanics and Surgical Space Conditions during Robot-Assisted Radical Prostatectomy: A Prospective Randomized Controlled Trial

The aim of this study was to investigate whether deep neuromuscular blockade (NMB) may affect intraoperative respiratory mechanics, surgical condition, and recovery profiles in patients undergoing robot-assisted radical prostatectomy (RARP). Patients were randomly assigned to the moderate or deep NMB groups. Pneumoperitoneum was maintained with carbon dioxide (CO(2)) insufflation at 15 mmHg during surgery. The primary outcome was peak inspiratory pressure (PIP) after CO(2) insufflation. Mean airway pressure (P(mean)) and dynamic lung compliance (C(dyn)) were also recorded. The surgeon rated the surgical condition and surgical difficulty on a five-point scale (1 = extremely poor; 2 = poor; 3 = acceptable; 4 = good; 5 = optimal). Recovery profiles, such as pulmonary complications, pain scores, and recovery time, were recorded. We included 58 patients in this study. No significant differences were observed regarding intraoperative respiratory mechanics including PIP, P(mean) and C(dyn), between the two groups. The number of patients with optimal surgical conditions was significantly higher in the deep than in the moderate NMB group (29 vs. 20, p = 0.014). We found no differences in recovery profiles. In conclusion, deep NMB had no significant effect on the intraoperative respiratory mechanics but resulted in optimal endoscopic surgical conditions during RARP compared with moderate NMB.