Context: Myocardial oxidative stress plays an essential role in the pathogenesis of ischaemia-reperfusion injury associated with coronary artery bypass grafting (CABG). Both propofol and volatile anaesthetics have been shown to reduce reactive oxygen species in experimental and clinical studies.
Main objective: To compare the influence of sevoflurane and propofol on myocardial oxidative stress markers (F2-isoprostanes and nitrates/nitrites) in coronary sinus blood samples from patients undergoing off-pump CABG.
Design and setting: Randomised controlled clinical study of patients scheduled for off-pump CABG in a tertiary academic university hospital from June 2007 to August 2009. Forty patients consented to enrolment and were assigned to receive either propofol or sevoflurane.
Interventions: Upon completion of the proximal anastomosis, a retroplegia cannula was inserted in the coronary sinus to obtain blood samples, according to the study protocol.
Main outcome measures: Markers of lipoperoxidation (F2-isoprostanes) and nitrosative stress (nitrates/nitrites) were measured in coronary sinus blood samples at three time points: after the end of the proximal anastomosis (T1), after completion of all grafts (T2) and 15 min after revascularisation (T3).
Results: Of the 40 recruited patients, 38 fully completed the study. In the sevoflurane group (n = 20), concentrations of oxidative stress markers in the coronary sinus remained almost constant and were significantly lower than those in the propofol group (n = 18) at all time points. F2-isoprostanes concentrations were as follows at T1: sevoflurane group 37.2 ± 27.5 pg ml vs. propofol group 170.7 ± 30.9 pg ml [95% confidence interval (CI) 112.16-155.08, P < 0.0001); at T2: sevoflurane group 31.94 ± 24.6 pg ml vs. propofol group 171.6 ± 29.7 pg ml (95% CI 119.78-159.63, P < 0.0001); and at T3: sevoflurane group 23.8 ± 13.0 pg ml vs. propofol group 43.6 ± 31 pg ml (95% CI 2.87-36.63, P = 0.023).
Conclusion: In patients undergoing off-pump CABG, sevoflurane showed better antioxidative properties than propofol.