ABSTRACT
Objective To study the feasibility and safety of limb remote ischemic preconditioning (RIPC) in infants and explore the protective effect on myecardium ischemia reperfusion injury for infants undergoing cardiac operation under cardiopulmonary bypass. Methods 60 infants weight less than 7 kilograms with ventricular septal defect were enrolled into the study. 30 of them (RIPC group) were ischemic preconditioned two times (24 hours and 1 hour preoperatively) by three cycles of iscbemia (5 minutes for each) and reperfusion on the left upper arm using a blood pressure cuff. Serum lactate dehydrogenase (LDH), creatine kinase (CK) and its isoenzyme (CK-MB), and tro-ponin I (TnI) ; malondialdehyde (MDA) and superoxide dismutase (SOD) was preoperatively detected. The expression of heat shock pro-tein 70 (HSP 70) in cardiomyocytes was determined by western blot analysis. The surgical outcome including limb movement and sensory function was also recorded. Results No limb disability or sensory disturbance or no other surgical complications was found in all infants. LDH, CK, TnI at the beginning of operation in RIPC group was higher than those in control group. After operation, leakage of heart enzymes were attenuated in RIPC group, and the serum concentration of enzymes were lower than those in the control group. The RIPC group had low coronary sinus venous concentration of MDA but high SOD. The expression of HSP70 was upregulated in cardiomyocytes of RIPC group. Conclusion The limb RIPC can be done easily and safety in infants, and BIPC can reduce the leakage of myocardial enzymes and upregu-late the expression of HSP, which possess protective effect on myocardial IRI.