Protective Effect Of Remifentanil Preconditioning On Myocardium Against Ischemia-reperfusion Injury During CPB And Remifentanil Used In Fast-track Cardiac Anesthesia

PARTâ… : Protective effect of remifentanil preconditioning on myocardium against ischemia-reperfusion injury during CPBObjective: To study the effect of remifentanil preconditioning on myocardium against ischemia-reperfusion injury during CPB in pediatric patients with congnitive heart disease. Methods Sixty children with ventricular septal defect were randomly divided into 4 groups (n=15 in each group). Control group were anesthetized with remifentanil 0.2～0.5μg·kg^-1·min^-1.R₁,R₂,R₃ group patients received 3 periods of 5 min remifentanil infusion at 1, 2, 4μg·kg^-1·min^-1 at 5 min interval before aortic occulsion.Vein blood sample were collected for the measurement of cTnI and CK-MB during perioperation.MAP and HR were recorded before aortic occulsion. Resurts After aortic unclamping 2 hours ,the concentrations of cTnI and CK-MB in group R₁,R₂,R₃ were lower than those in control group. Compared to R1 group, the concentrations of cTnI in R3 group were lower . There was no significant difference in MAP and HR before aortic occulsion among the 4 groups. Conclusion Remifentanil can protect myocardium against ischemia-reperfusion injury during CPB in congnitive heart disease by mimicing ischemia proconditioning. PARTâ…¡: Remifentanil used in fast-track cardiac anesthesia Objective To assess the hemodynamic stability and security of early extubation with remifentanil and propofol TCI in patients undergoing double cardiac valve replacement. Methods Twenty patients with rheumatic heart disease undergoing aortic and mitral valve replacement were randomly divided into remifentanil group (PR group, n =10) and fentanyl group(PF group n=10). Anesthesia was induced with midazolam 0.05mg/kg,etomidate0.3mg/kg, vecuronium 0.1mg/kg ,remifentanil 1.0ug/kg(group PR) or fentanyl 5ug/kg(group PF). Anesthesia was maintained with a continuous infusion of remifentanil 0.25⁰.5μg·kg^-1·min^-1 (group PR) or fentanyl intermittently injection 2～3μg/ kg (group PF), with propofol TCI at a target plasma concentration of 1.5～2.0μg /ml and vecuronium intermittently injection to keep muscle relaxant. Swan-Ganz catheter was placed in pulmonary artery via right internal jugular vein for mixed venous blood O2 saturation (SvO2) and hemodynanic monitoring before induction of anesthesia.The hemodynamic parameters were recorded before induction of anesthesia (T₀),postinduction (T₁), postintubation 2min (T₂), poststernotomy 2min(T₃),prebypass 10min (T₄), postbypass 10min (T₅) and poststernal closure (T₆).Extubation times,ICU and hospital lengths of stay ,dose of dopamine and nitroglycerin were also recorded. Results Compared with the baseline values (T₀), PR group induction caused a fall in HR, MAP ,SVRI andPVRI(P<0.01), whereas the stimulus of intubation was slightly. There was a reduction in MAP,MPAP,SVRI and PVRI in PF group after induction (P<0.01). There was no significant difference between the two groups in hemodynamic parameters. In both groups, SvO2 was more than 70%.Extubation times and ICU lengths of stay were significantly shorter in the PR group(P<0.01). Dose of dopamine and nitroglycerin in PR group were less than in PF group ( P<0.05 ) . Conclusion Remifentanil combined with propofol TCI anesthesia not only resulted in hemodynamic stability in double cardiac valve replacement surgery ,but also shortened extubation times and ICU lengths of stay.