Suggested Electroacupuncture for Postoperative Nausea and Vomiting: A Comprehensive Meta-Analysis and Systematic Review of Randomized Controlled Trials

BACKGROUND The purpose of this meta-analysis was to evaluate the effectiveness of electroacupuncture in preventing and treating postoperative nausea and vomiting (PONV) after general anesthesia. MATERIAL AND METHODS We searched for papers on randomized controlled trials on electroacupuncture for PONV prevention after general anesthesia published in PubMed, Web of Science, and China National Knowledge Infrastructure (CNKI) since October 1, 2016. Primary outcome was incidence of PONV; secondary outcomes were incidence of postoperative nausea (PON) at 6 h, postoperative vomiting (POV) at 6 h, and postoperative antiemetic requirement. Data were combined and analyzed using RevMan 5.4.1 software. RESULTS Eight randomized controlled trials, with 899 total participants, were included. Findings showed (1) there was no significant difference in occurrence rate of PONV between electroacupuncture and control groups (OR=0.31, 95% CI [0.06, 1.49], P=0.14, I²=82%); (2) electroacupuncture reduced incidence of PON at 6 h postoperatively, compared with controls (OR=0.43, 95% CI [0.27, 0.67], P=0.0002, I²=0%); (3) compared with control group, electroacupuncture reduced POV incidence 0-6 h postoperatively (OR=0.38, 95% CI [0.23, 0.63], P=0.0001, I²=0%); (4) electroacupuncture group demonstrated a significant reduction in postoperative requirement for antiemetic medications (OR=0.44, 95% CI [0.25, 0.78], P=0.005, I²=61%); (5) one study reported adverse reactions during observation, with 3 patients experiencing pain and itching at acupuncture site and 2 patients refusing a second acupuncture treatment; all symptoms lasted less than 2 h. CONCLUSIONS Based on current evidence, electroacupuncture significantly reduces the occurrence rate of PON and POV at 6 h after surgery and the use of antiemetic medication postoperatively. However, more high-quality, large-sample randomized controlled trials are needed to further validate its efficacy.