Post-operative nausea and vomiting prophylaxis: A meta-review on systematic reviews and meta-analyses

Introduction: Postoperative nausea and vomiting (PONV) are common complications in surgical patients undergoing general anesthesia, and multiple strategies have been suggested to prevent them. Objective: To describe the available evidence on the effectiveness of pharmacological and non-pharmacological strategies for preventing PONV in adults undergoing surgery under general anesthesia, as reported in previous meta-analyses and systematic reviews. Methodology: An overview of systematic reviews and meta-analyses was conducted. Searches were performed in PubMed, EBSCO, EMBASE, Cochrane Database, Science Direct, and Scopus, without restrictions as to gender, clinical condition, or date of publication, including articles in Spanish, French, and English only. Two reviewers independently and in duplicate did the screening, data extraction, quality evaluation, and risk of bias assessment according to AMSTAR-2. The PRISMA and PRIOR statements were followed for reporting. PROSPERO registration number CRD42021251999. Results: Out of 80 candidate articles, three were viable for meta-analysis. 1.5 mg to 18 mg doses of Dexamethasone showed a significant reduction in the risk of PONV, with a RR of 0.48 (95 % CI 0.41-0.57; p<0.001), I2=63 % (p=0.07), and a NNTc of 5 and 7. Other effective strategies included the use of acoustic stimulation/acupuncture/acupressure, 5HT3 antagonists, NK1 antagonists, gabapentinoids, haloperidol, droperidol, metoclopramide, midazolam, mirtazapine, among others. The risk of publication bias was low. Conclusion: Different strategies are effective for PONV prophylaxis in surgeries under general anesthesia. Dexamethasone shows the best available evidence at the moment. The documented methodological quality suggests the need for better studies to establish the effectiveness of the strategies.