Effect of remifentanil postconditioning on myocardial ischemia-reperfusion injury in patients undergoing open heart surgery under CPB

Abstract

Objective To evaluate the effect of remffentanil postconditioning on myocardial ischemiareperfusion (I/R) injury in patients undergoing open heart surgery under CPB.Methods Thirty patients (ASA grade Ⅱ or Ⅲ, NYHA class Ⅰ or Ⅱ ) of both sexes aged 18-45 yr undergoing repair: of ventricular septal defect and/or atrial septal defect under CPB were randomly divided into 2 groups ( n = 15 each): control group (group C)and remifentanil postconditioning group (group R). Anesthesia was induced with midazolam, sufcntanil, propofol and rocuronium. The patients received 5 min infusion of remifentanil at 4 μg · kg- 1 · min - 1 8 min before aortic unclamping in group R, while the patients received equal volume of normal saline in group C. Blood samples were obtained from the right internal jugular vein for determination of plasma concentrations of cardiac troponin-I (cTnI)and MDA and activities of CK-MB and SOD before induction of anesthesia (baseline) and at4, 8, 24 and48 h after aortic unclamping. Results The plasma concentrations of cTnI and MDA and activity of CK-MB were significantly lower, while the plasma SOD activity was significantly higher at 4 and 8 h after aortic unclmping, and the plasma concentration of MDA was significantly lower at 24 h after aortic unclamping in group R than in group C ( P ＜ 0.05 ). Conclusion Remifentanil postconditioning can attenuate myocardial I/R injury in patients undergoing open heart surgery under CPB through inhibiting lipid peroxidation. Key words: Piperidines; Myocardial reperfusion injury; Cardiopulmonary bypass; Ischemic postconditioning