Comparative efficacy of intravenous treatments for perioperative shivering in patients undergoing caesarean delivery under neuraxial anaesthesia: A systematic review and Bayesian network meta-analysis of randomised-controlled trials

Introduction: Shivering affects 52 % of patients undergoing caesarean delivery under neuraxial anaesthesia. Despite extensive research focused on its prevention, there is still no consensus regarding optimal pharmacological treatment. This systematic review and network meta-analysis aims to compare available intravenous treatments of perioperative shivering in patients undergoing caesarean delivery under neuraxial anaesthesia. Methods: We searched seven databases (PubMed MEDLINE, Scopus, Web of Science, Embase, LILACS, Cochrane CRCT and clinicaltrials.gov) for randomised controlled trials comparing intravenous treatments of perioperative shivering during caesarean delivery and performed a Bayesian model network meta-analysis. We assessed study quality using the Cochrane risk of bias assessment tool. The primary outcome evaluated in this meta-analysis was shivering control (cessation or significant reduction in intensity), and secondary outcomes included time to shivering control, shivering recurrence, and incidence of maternal nausea. Results: Twenty randomised controlled trials, with a total of 1983 patients, were included in this analysis. Network estimates of odds ratios (OR [95 % Credible Interval]) of effective treatment of shivering compared with saline were: dexmedetomidine (38.1 [14.2 to 111.5]), tramadol (33.6 [15.1 to 81.8]), nalbuphine (26.2 [10.8 to 80.2]), meperidine (20.9 [6.2 to 73.1]), ondansetron (6.6 [2.2 to 23.2]), and clonidine (3.2 [0.6 to 14.9]). The rank order of interventions by surface area under the cumulative ranking curve scores (in parenthesis) for shivering control was dexmedetomidine (0.87) > tramadol (0.85) > nalbuphine (0.74) > meperidine (0.66) > ondansetron (0.41) > clonidine (0.3) > amitriptyline (0.03). Dexmedetomidine was also the top-ranked intervention for time to shivering control, shivering recurrence and maternal nausea. We judged the certainty in the evidence to be moderate for dexmedetomidine and nalbuphine, and low for all other interventions. Conclusion: This network meta-analysis identified four effective intravenous treatments for shivering in patients undergoing caesarean delivery under neuraxial anaesthesia: dexmedetomidine, tramadol, nalbuphine and meperidine. Dexmedetomidine was the top-ranked intervention for all outcomes.