Background: α2 adrenoceptor agonists have been proposed as adjuncts to prolong analgesia in pediatric caudal block. The aim of this meta-analysis was to compare the analgesic efficacy of caudal vs intravenous α2 adrenoceptor agonists during pediatric caudal block.
Methods: A systematic search, data extraction, bias risk assessment, and pooled data analysis were performed following the PRISMA guidelines. All randomized controlled trials comparing caudal with intravenous α2 adrenoceptor agonists in pediatric caudal block were included. Relative risk and weighted mean differences (the corresponding 95% confidence intervals) were calculated for dichotomous and continuous data, respectively. Trial sequential analyses were performed to evaluate the credibility of the meta-analysis.
Results: A total of 244 patients in five trials were identified. Compared with the intravenous group (9.56 ± 4.23 hours), the time to the first rescue analgesia was prolonged in the caudal α2 adrenoceptor agonists group (12.72 ± 5.99 hours) by a weighted mean difference of 2.98 hours [95% confidence interval: 0.59-5.36 hours; P = .01]. The number of children requiring rescue analgesia in the caudal group (64, 66.67%) was lower than that in the intravenous group (80, 81.63%) [relative risk = 0.82; 95% confidence interval: 0.69-0.97; P = .02]. These findings were also verified by trial sequential analysis. There were no significant differences in the side effects.
Conclusion: Caudal α2 adrenoceptor agonists as adjuncts to local anesthetic during pediatric caudal block are more effective than intravenous injection. However, the results were affected by small sample size and significant heterogeneity.
Keywords: analgesia; caudal block; meta-analysis; postoperative pain; α2 adrenoceptor agonists.
© 2020 John Wiley & Sons Ltd.