Effects of quadratus lumborum block on perioperative multimodal analgesia and postoperative outcomes in patients undergoing radical prostatectomy

Background: This study aimed to investigate the effects of ultrasound- guided quadratus lumborum block (QLB) on perioperative multimodal analgesia and postoperative outcomes in patients undergoing radical prostatectomy. Methods: A total of 80 patients undergoing radical prostatectomy were randomly divided into two groups: general anaesthesia with QLB (QLB group; n = 40) and general anaesthesia with sham QLB (normal saline [NS] group; n = 40). QLB or sham QLB was performed before the induction of anaesthesia. Sufentanil was intravenously administered for postoperative analgesia. The primary outcome was the pain score (measured using a numerical rating scale [NRS]) at different time points within 48 h postoperatively. Secondary outcomes included the cumulative dose of sufentanil within 48 h postoperatively, subjective comfort, grip strength, first time of exhaustion, first fluid intake time, time to get out of bed, length of postoperative hospital stay and overall satisfaction. The SPSS software, version 17.0, was used for all statistical analyses. Results: Postoperative NRS at rest was significantly lower at 2 h (1.7 +/- 1.1 versus 3.0 +/- 2.1), 4 h (1.8 +/- 1.2 versus 4.1 +/- 2.3), 6 h (1.9 +/- 2 versus 4.4 +/- 2) and 12 h (3.5 +/- 2.3 versus 5 +/- 3.3) and was also lower when coughing at 2 h (2.3 +/- 1.1 versus 4 +/- 2.1), 4 h (2.3 +/- 1. 1 versus 4.3 +/- 2) and 6 h (2.4 +/- 1.1 versus 5.9 +/- 2.3) in the QLB than that in the NS group. The cumulative dose of sufentanil was significantly lower in the QLB than that in the NS group at 4 h, 6 h, 12 h, 24 h and 48 h. The nausea score was significantly lower in the QLB group at 24 h postoperatively, and the first time of exhaustion and time to get out of bed were significantly shorter (P < 0.05). The overall satisfaction score was significantly higher in the QLB than in the NS group (4 +/- 0.7 versus 2.6 +/- 0.9). Conclusion: Ultrasound-guided bilateral QLB can provide effective postoperative analgesia for patients undergoing radical prostatectomy, reduce the need for sufentanil, facilitate comfort and improve postoperative outcomes. QLB can be a good component of multimodal analgesia.