关键词: 心肌再灌注损伤, 七氟醚, 缺血预处理, 心肌

Abstract: OcjectiVe To interpret the perioperative myocardial protection of sevoflurane preconditioning during myocardial ischemia/reperfuison injury( MI/RI)caused by open-heart surgery in congenital heart disease children. Methods Forty patients of scheduled for repair to ventricular septal defect(VSD)and to atrial septal defect(ASD)were randomly divided into two groups,control group (group C,n =20)and sevoflurane preconditioning group(group S,n =20). In group S,2MAC of sevoflurane was continuously inhaled from the beginning of operation to the beginning of cardiopulmonary bypass( CPB),and no anesthetic used sevoflurane in group C. Patients of anesthesia were injected with intravenous midazolam(0. 08-0. 12mg/kg),fentanyl(5-10μg/kg)and vecuronium(0. 1mg/kg)and anesthesia was maintained with midazolam,fentanyl and vecuronium in intermittent iv boluses was induced. The time of clamping aorta,cardiopulmonary bypass and operating,the rate of spontaneously rebeating of heart and the situation of electrocution defibrillation were recorded. The plasma levels of creatine phosphokinase isoenzyme( CK-MB),cardiac troponin I( cTnI),malondialdehyde( MDA)and the activity of superoXide dismutase(SOD)were measured after induction of anesthesia(T0),10minutes after aorta unclamping(T1),immediately after CPB(T2),6h(T3)and 24h(T4)after CPB. Results All patients were similar with regard to demographic data between two groups(p >0. 05). cTnI,CK-MB, MDA in both group increased at T1 ,reached peak at T3 and declined at T4 . The cTnI,MDA level at T1-4 were higher than that at T0( p <0 . 01 ). There were no significant difference at T0 between two groups (p>0. 05),the cTnI,MDA level at T1-4 in group S was lower than that in group C(p<0. 01). The CK-MB level at T1-4 was higher than that at T0( p <0. 01 ). There was no significant difference at T0-3 between two groups( p>0. 05 ),the CK-MB level at T4 in group S was lower than that in group C( p<0. 01). The SOD activity at T1-3 was higher than that at T0( p <0. 01 ). In group S,there was no significant difference at T1-4 when compared with T0 . There was no significant difference at T0 between two groups( p>0 . 05 ),the SOD activity at T1-3 in group S was higher than that in group C( p<0 . 01 ). Conclusion Sevoflurane preconditioning will be a novel therapeutic strategy to reduce the risk of myocardial MI/RI during open-heart surgery with CPB in children.

Key words: myocardial reperfusion injury, sevoflurane, ischemic preconditioning, myocardial