PLASMA VITAMIN-E AND VITAMIN-C CONCENTRATIONS OF ADULT PATIENTS DURING CARDIOPULMONARY BYPASS

Objective: This study was designed with two aims: 1) to determine if t he coronary artery bypass graft (CABG) procedure alters plasma vitamin E and C concentrations of adult patients through repeated determinati ons of vitamin levels at time points before, during and following CABG , and 2) to assess whether plasma vitamin E concentrations reflect myo cardial tissue content. Methods: A consecutive sample of 38 patients u ndergoing CABG surgery at a Midwest tertiary care hospital was enrolle d. Patients receiving blood transfusions before or during surgery were excluded. Results: Plasma vitamin E/total lipid ratios rose with repe rfusion, remained elevated immediately following bypass, and fell to p reoperative concentrations by 24 hours. Plasma vitamin E/total cholest erol levels varied little throughout this time course. Both plasma uri c acid and ascorbate concentrations (corrected for hemodilution) also rose by the preischemic interval, and remained elevated until a return to preoperative levels by 24 hours. Corrected malondialdehyde (MDA) c oncentrations rose by pre-ischemia but returned more quickly to preope rative levels. Atrial appendage tissue vitamin E concentrations bore a significant relationship to those of plasma prior to surgery (r = +0. 49, p = 0.004). Reported supplement use, plasma concentrations and bod y mass index contributed to the variability in atrial tissue concentra tions of vitamin E. Conclusions: In short, when not confounded by tran sfusions or hemodilution, several peripheral indices of antioxidants i ncrease with the reperfusion segment of CABG procedure and return to b aseline levels within 24 hours of surgery. Parallel changes in MDA wer e observed. The observed changes are consistent with the hypothesis th at oxidative stress accompanies the ischemia-reperfusion components of the CABG procedure.