The effect of desflurane and propofol protocols on preconditioning

Abstract

Background. Preconditioning is one of the most powerful mechanisms preventing the myocardial ischemic damage that occurs during coronary artery bypass grafting. Objectives. We aimed to investigate the effects of different propofol and/or desflurane administration protocols in terms of the prevention of ischaemia-reperfusion damage. Material and methods. Ninety patients, aged > 18 years, American Society of Anesthesiologists (ASA) category III, scheduled to undergo primary elective coronary artery bypass grafting (CABG), were included in the study. During maintenance, the patients in group 1 (n = 30) received a propofol infusion (5-6 mg/kg/h) combined with a fentanyl infusion (3-5 mcg/kg/h); the patients in group 2 (n = 30) also received a propofol infusion (5-6 mg/kg/h) combined with a fentanyl infusion (3-5 mcg/kg/h), but they were also given 6% desflurane inhalation for 15 min both before cross-clamping of the aorta and after removal of the clamp; the patients in group 3 (n = 30) received a propofol infusion (2-3 mg/kg/h) combined with a fentanyl infusion (3-5 mcg/kg/h) and received the continuous 6% desflurane inhalation. Blood samples were drawn in the preoperative period (S1), during cardiopulmonary bypass, before cross-clamping the aorta (S2), after removal of the cross-clamp (S3) and 24 h after the operation (S4). Results. All groups were similar in terms of age and BMI (p > 0.05). TNF-á levels were higher at S3 compared to S1, S2 and S4 (p > 0.001). The TNF-á levels at S4 were lower in group 3 than those in group 1 and group 2 (p < 0.05). In all groups, h-FABP levels showed an increase in S3 but were significantly lower at S4 (p < 0.05). In group 3, h-FABP levels at S2 and S3 were significantly lower than those in group 1 (p < 0.05). There was a moderate correlation between h-FABP and TNF-á levels (Spearman's rho = 0.472, p < 0.001). Conclusions. On the basis of the measurement of h-FABP and TNF-á, low-dose propofol and continuous desflurane inhalation provide more effective preconditioning than propofol alone or a short course of desflurane in patients undergoing CABG.