Remote Ischemic Preconditioning Fails to Benefit Pediatric Patients Undergoing Congenital Cardiac Surgery: A Meta-Analysis of Randomized Controlled Trials

Remote ischemic preconditioning (RIPC) has been proven to reduce the ischemia-reperfusion injury. However, its effect on children receiving congenital cardiac surgery (CCS) was inconsistent. We therefore performed the current meta-analysis of randomized controlled trials (RCTs) to comprehensively evaluate the effect of RIPC in pediatric patients undergoing CCS. PubMed, Embase, and Cochrane library were searched to identify RCTs assessing the effect of RIPC in pediatric patients undergoing CCS. The outcomes included the duration of mechanical ventilation (MV), intensive care unit (ICU) length of stay, postoperative cardiac troponin (cTnI) level, hospital length of stay (HLOS), postoperative inotropic score, and mortality. Subgroup and sensitivity analysis were also performed as predesigned. The meta-analysis was performed with random-effects model despite of heterogeneity. Sensitivity and subgroup analysis were predesigned to identify the robustness of the pooled estimate. Nine RCTs with 697 pediatric patients were included in the meta-analysis. Overall, RIPC failed to alter clinical outcomes of duration of MV (standard mean difference [SMD] −0.03, 95% confidence interval [CI] −0.23–0.17), ICU length of stay (SMD −0.22, 95% CI −0.47–0.04), or HLOS (SMD −0.14, 95% CI −0.55–0.26). Additionally, RIPC could not reduce postoperative cTnI (at 4–6 hours: SMD −0.25, 95% CI −0.73–0.23; P = 0.311; at 20–24 hours: SMD 0.09, 95% CI −0.51–0.68; P = 0.778) or postoperative inotropic score (at 4–6 hours: SMD −0.19, 95% CI −0.51–0.14; P = 0.264; at 24 hours: SMD −0.15, 95% CI −0.49–0.18; P = 0.365). RIPC may have no beneficial effects in children undergoing CCS. However, this finding should be interpreted with caution because of heterogeneity and large-scale RCTs are still needed.