Intravenous dexmedetomidine versus intravenous clonidine for post spinal anesthesia shivering: a meta-analysis of randomized controlled trials

Background Dexmedetomidine and clonidine are the most extensively studied drugs for shivering treatment, because alpha(2)-adrenergic agonists can reduce the shivering threshold. The objective of this meta-analysis was to compare the efficacy and complications of dexmedetomidine with those of clonidine, when used for control of post spinal anesthesia shivering. Methods Electronic databases were searched for randomized controlled trials (RCT) comparing the effect of dexmedetomidine versus clonidine for control of post spinal anesthesia shivering. The endpoints were effective rate of shivering treatment, time to cease shivering, recurrent rate of shivering and complications. Results Six studies comprising 340 adult patients were included in this meta-analysis. Dexmedetomidine had higher effective rate of shivering treatment (odds ratio [OR]: 4.11, 95% confidence interval (CI): [1.53, 11.07],P = 0.005), shorter time to cease shivering (Mean differences (MD)=-1.91; 95% CI [-3.66, -0.15],P = 0.03), lower recurrent rate of shivering (OR = 0.30; 95% CI [0.12, 0.75],P = 0.01), compared to clonidine. Dexmedetomidine had a lower rate of hypotension and higher incidence of sedation than clonidine. Conclusions Dexmedetomidine is superior to clonidine when used for shivering treatment after spinal anesthesia, because of higher incidence of effective rate and sedation, faster control of shivering, lower incidence of recurrent rate and hypotention.