[A Meta-analysis of high-dose epinephrine in children with cardiopulmonary arrest]

Epinephrine has a place in the treatment of pediatric cardiopulmonary arrest but has been controversy concerning its optimal dose. This meta-analysis aimed to seek for evidences of the effectiveness of different doses of epinephrine in children with cardiac arrest and to evaluate the effectiveness of high-dose versus standard-dose epinephrine in children with cardiac arrest.

Published papers on randomized controlled trials (RCTs) and prospective clinical controlled trials (CCTs) were electronically searched from MEDLINE (1966 to September 2006), EMBASE (1974 to June 2006), the Cochrane Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 3, 2006), CBM (1998 to 2006) and CNKI (1994 to 2006). We also had searched the related references and manual retrieval 10 professional academic journals about epinephrine treatment of pediatric cardiopulmonary arrest (1998 to 2006). The search strategy was made according to the collaborative review group search strategy. At first, we found 546 articles. Second, we excluded 474 of them through reading the title, abstract, excluding non-randomized, non-controlled trials and non-clinical studies. Finally, we identified 4 papers through searching for original articles and telephone contact with some of the authors after excluding 68 papers. Then we performed the meta-analysis by RevMan 4.2.7. For homogenous dichotomous data (P > or = 0.1, I(2) < or = 50%) we calculated fixed effects model, relative risk (RR), 95% confidence intervals (CI), For heterogeneity Dichotomous data (P < 0.1, I(2)>50%) we calculated random effects model, relative risk (RR) and 95% confidence intervals (CI).

Four trials involving 360 cases were included. The results of meta-analysis indicated that there were no statistical difference in recovery of spontaneous circulation [RR = 1.28, 95% CI (0.93, 1.77)]. Perondi, Patterson and Cheng xiuyong's study compared the rate of survival at 24 hours and showed statistical heterogeneity (P = 0.01, I(2) = 0.77). The random effects model indicated that there were no significant difference [RR = 1.40, 95% CI (0.43, 4.55)]. The sensitivity analysis showed that after deleting Perondi's group there were no statistical heterogeneity. Fixed effects model indicated that there were significant difference [RR = 2.50, 95% CI (1.52, 4.11)]. T When the rates of survival to hospital discharge were compared among the 4 studies, there was statistical heterogeneity (P = 0.07, I(2) = 0.58), the random effects model indicated that there were no statistical difference [RR = 1.78, 95% CI (0.42, 7.50)], There were no heterogeneity after Cheng Xiu-yong group was deleted.

Higher doses of epinephrine in children with cardiopulmonary arrest may not increase the rate of recovery of spontaneous circulation, the rate of survival at 24 hours, the rate of survival to hospital discharge and worsen the neurological outcomes. Adverse reactions is difficult to monitor and evaluate because of the current restrictions on medical technology.