Role of intravenous dexmedetomidine in the prevention and treatment of shivering in pregnant patients undergoing cesarean section under central neuraxial blockade: A systematic review and meta-analysis

Background and Aims: Dexmedetomidine has been used as an anti-shivering agent in the perioperative period in pregnant patients undergoing caesarean section (CS), but its effectiveness remains inconclusive. This systematic review and meta-analysis aimed to assess the efficacy of intravenous Dexmedetomidine in the management of shivering. Methods: PubMed, MEDLINE, Embase, Scopus, Web of Science, CENTRAL, and Google Scholar were explored for the randomised controlled trials (RCTs), which compared intravenous administration of Dexmedetomidine with normal saline (placebo) or other anti-shivering agents for the prevention or treatment of shivering in pregnant patients undergoing CS under central neuraxial blockade. The primary outcome was either incidence and/or severity (for prevention) and duration and/or success rate (for treatment) of shivering between the two groups. The secondary outcome measures were adverse effects (bradycardia, hypotension, sedation, nausea and vomiting, and effect on the APGAR scores of the baby) if observed. Data were synthesised using a random effect model. We calculated the odds ratio (95% CI) for presenting the categorical outcome and standardized mean difference (95% CI) for continuous outcomes. Heterogeneity was assessed using I2 statistics and was investigated using sensitivity analysis. Results: A total of 15 RCTs were included in the present systematic review and data from 10 RCTs comparing Dexmedetomidine with normal saline were pooled into the meta-analysis for primary outcome measure. The incidence and severity of shivering at 30 and 60 minutes weresignificantly less in the Dexmedetomidine group compared to the normal saline group [OR = 0.30, 95% CI: 0.19 to 0.47, P < 0.0001; MD = -0.54, 95% CI: -0.81 to -0.26, Z = 3.78, P = 0.0002 and MD = -1.06, 95% CI: -1.46 to -0.66, Z = 5.23, P < 0.0001 respectively]. Similarly, the time to reduce shivering was significantly lower and the success rate of treatment was higher in the Dexmedetomidine group compared to the normal saline group [MD = -13.55, 95% CI: −17.78 to -9.12, Z = 6.0, P < 0.0001 and OR = 0.03, 95% CI: 0.02 to 0.07, P < 0.0001 respectively]. There was no heterogeneity among the studies for incidence, severity at 60 minutes, and success rate of treatment outcome, while the severity of shivering at 30 minutes and time to reduce shivering demonstrated moderate heterogeneity. The side effect profile was comparable between the Dexmedetomidine and control (active and passive) group. Conclusion: This meta-analysis shows that intravenous administration of Dexmedetomidine for both prophylaxis and treatment is superior to normal saline in the management of perioperative shivering during CS, but is comparable to other most commonly used anti-shivering agents. There is no statistically significant difference in the incidence of side effects between the two groups.