Abstract: AIM: To observe the cardioprotective effects of propofol, isoflurane and their combination by comparing changes of plasma concentrations of cTnI, CKMB, SOD and MDA during open heart surgery.METHODS: Sixty patients, scheduled for elective coronary artery bypass graft, were randomly divided into control, propofol, isoflurane and their combined use groups, respectively.In Group propofol, isoflurane or combined use groups, propofol, isoflurane or propofol combined with isoflurane were given respectively.The venous blood samples were taken to measure plasma concentrations of cTnI, CK-MB, SOD andMDA before CPB beginning (T₀), and 30 min after release of aortic cross-clamp (T₁), 4 h(T₂), 24 h(T₃), and 48 h (T₄) after CPB stop.RESULTS: The plasma concentrations of cTnI, CK-MB and MDA in all patients after T1 increased in different extent, the plasma concentrations of cTnI and MDA in group propofol, isoflurane and combined use groups at T₂ and T₃ were much lower than those of group control, the plasma concentration of cTnI in group M at T₃ was much lower than that in group propofol (P<0.05), and the rate of heart automatic beating after release of aortic cross-clamp in combined use groups was much higher than those in the other groups (P<0.05).CONCLUSION: Anesthetic uses of propofol and isoflurane, specially combined use,can reduce myocardial ischemia-reperfusion injury induced by oxygen free radical in patients undergoing coronary artery bypass graft.

Key words: propofol, isoflurane, oxygen free radical, troponin I, coronary artery bypass graft