Efficacy of transmuscular quadratus lumborum block on postoperative nausea and vomiting: A meta-analysis of randomized controlled trials

BACKGROUND: The use of transmuscular quadratus lumborum block (TQLB) offers potent pain relief in surgical interventions; nonetheless, the evidence is inadequate to prove its benefits in treating nausea and vomiting. This meta-analysis aimed to calculate the impact of TQLB on postoperative nausea and vomiting. METHODS: Two investigators carried out investigations for randomized controlled trials from Embase, PubMed, and the Cochrane Library, respectively. We used Review Manager software for the meta-analysis. RESULTS: Twelve trials with 725 patients were included. The incidences of postoperative nausea (risk ratio [RR]: 0.59, 95% confidence interval [CI]: 0.44-0.78) and postoperative vomiting (RR: 0.29, 95% CI: 0.09-0.88) in the TQLB group were notably less than those in the control group without publication bias as high-quality evidence evaluated by Grading of Recommendations Assessment, Development and Evaluation. TQLB could reduce the rest (standardized mean difference [SMD]: -0.53, 95% CI: -0.89 to -0.17) and activity (SMD: -0.48, 95% CI: -0.78 to -0.18). Numeric rating scale at the 6 hours after the operation, the rest and activity visual analogue scale (VAS) at both of the 6 hours (rest VAS: SMD: -1.01, 95% CI: -1.91 to -0.11; activity VAS: SMD: -0.89, 95% CI: -1.48 to -0.30) and 24 hours (rest VAS: SMD: -0.64, 95% CI: -1.15 to -0.12; activity VAS: SMD: -1.74, 95% CI: -2.39 to -1.10) after the surgery. TQLB could shorten the time to first ambulation (SMD: -0.54, 95% CI: -0.96 to -0.11), intestinal movement (SMD: -1.06, 95% CI: -1.43 to -0.69), and length of hospital stay (SMD: -0.89, 95% CI: -1.32 to -0.45). TQLB could notably decrease the incidence of rescue analgesia administration (RR: 0.49, 95% CI: 0.27-0.88) and increase the satisfaction degree (RR: 4.10, 95% CI: 2.41-6.99). The generalizability and interpretation of these results are constrained by the study's limited sample size, the exploratory analysis of secondary endpoints, and potential heterogeneity. CONCLUSION: TQLB may decrease the incidence of postoperative nausea and vomiting, enhance postoperative pain management, accelerate postoperative recovery, and increase the satisfaction degree of patients. These benefits highlight the potential efficacy of TQLB to ensure safer and faster recovery following surgical procedures as high-quality evidence.