[Change in plasma free 15 - F2t - isoprostane concentrations in smoking patients undergoing coronary artery bypass grafting and its clinical significance]

To investigate the change in plasma free 15-F2t-isoprostane fn(15-F(2t)-IsoP) concentration and its relationship with postoperative cardiac function of smoking patients who underwent coronary artery bypass grafting (CABG).Sixty patients with coronary artery heart disease were divided into smoking group [n=30, age 54-69 years old, American Heart Association (AHA)II-III] and non-smoking group(n=30, age 58-70 years old, ASA II-III). All the patients were scheduled for CABG under combination anesthesia with isoflurane and fentanyl and conventional cardiopulmonary bypass. Blood samples were drawn from the central vein to measure 15-F(2t)-IsoP at the following time points: before operation (T0); 30 minutes after aortic clamping for cardiopulmonary bypass(T1); 10 and 30 minutes after aortic declamping(T2,T3).There was no statistical difference in 15-F(2t)-IsoP between two groups at T0, but contents of 15-F(2t)-IsoP in the two groups was increased markedly at T1, compared to those at T0 (P0.05 and P0.01 for smoking and non-smoking groups, respectively), and the degree of increase of 15-F(2t)-IsoP in smoking group was significantly higher than that in non-smoking group(P0.05). During reperfusion period (at T2,T3), the rate of lowering of 15-F(2t)-IsoP in smoking group was slower than that in non-smoking group(P0.05), and moreover, these patients needed more inotropic support than those in non-smoking group.Smoking patients have weaker anti-oxidation capability during CABG, therefore they have higher incidence of low cardiac function.