Effect of stellate ganglion block on postoperative nausea and vomiting after general anesthesia: A meta-analysis, meta-regression and trial sequential analysis of randomized controlled trials

Abstract

Objective Stellate ganglion block (SGB) accelerates the return of gastrointestinal transit and improves gastrointestinal function after surgery. However, it is unclear whether such benefits translate into less postoperative nausea and vomiting (PONV). The aim of this meta-analysis was to identify the effect of SGB on the incidence of PONV after general anesthesia. Methods We systematically searched electronic databases for published randomized controlled trials (RCTs) comparing SGB with placebo or no SGB for reducing PONV after general anesthesia. The primary outcome was the incidence of PONV after general anesthesia. The effect size was estimated by calculating the risk ratio (RR), with 95% confidence interval (CI). Trial sequential analysis (TSA) was also carried out to calculate the required information size. Results 16 RCTs including 1385 patients were included in the study. SGB significantly reduced the incidence of PONV (RR, 0.59, 95% CI, 0.49–0.70, P < 0.0001). In addition, TSA indicated that the Z curve for SGB not only crossed the conventional boundary, but also the TSA boundary for benefit. Meta-regression analyses found no significant impact of age, female proportion, type of surgery, type of anesthesia, sample size and prophylactic administration of antiemetic on the correlation between SGB and the risk of PONV. Conclusion This meta-analysis suggested an association of SGB with a decreased incidence of PONV after general anesthesia. TSA suggested that further studies are unlikely to alter the conclusions regarding the incidence of PONV.