Cardioprotective effect of remote ischemic postconditioning on children undergoing cardiac surgery: a randomized controlled trial

Background Remote ischemic postconditioning (RPostC) is a noninvasive intervention that has demonstrated cardioprotection and neuroprotection in animal studies. Objective Our goal was to investigate the cardio-cerebral protective effects of RPostC on children undergoing open-heart surgery for repair of congenital heart defects (CHD). Methods Children undergoing open-heart repair of CHD were randomly assigned to a RPostC or control group. RPostC was induced by three 5-min cycles of lower limb ischemia and reperfusion using a blood pressure cuff (200mmHg) at the onset of aortic unclamping. Serum cardiac troponin I (cTnI), creatine kinase-MB (CK-MB), neuron-specific enolase (NSE), S100, cytokines, and clinical outcomes were assessed. Results There were 35 children in the control group and 34 in the RPostC group. The mean age (3.64 +/- 1.95years vs. 3.45 +/- 3.02years, P=0.80), weight (15.11 +/- 6.91kg vs. 13.40 +/- 6.33kg, P=0.37), surgical time (144.82 +/- 38.51min vs. 129.92 +/- 30.76min, P=0.15), and bypass time (78.01 +/- 27.22min vs. 72.52 +/- 26.05min, P=0.49) were not different. Compared with the control group, the postoperative levels of cTnI (P=0.037) and CK-MB (P=0.046) were significantly reduced in the RPostC group. Furthermore, the MAP was higher (P=0.008), and ICU stay (36.87 +/- 3.30h vs. 60.57 +/- 7.35h, P=0.006) and postoperative hospital stay (8.56 +/- 1.50days vs. 10.06 +/- 2.41days, P=0.048) were shorter in the RPostC group than in the control group. However, the postoperative CVP and the concentrations of NSE, S100, CRP, TNF-, IL-1, IL-6, and IL-10 were not significantly different. Conclusion RPostC significantly alleviates cardiac injury in children undergoing open-heart repair of CHD and may also reduce cerebral injury.