Plasma vitamin E and A changes during cardiopulmonary bypass and in the postoperative course

Abstract

Background. Cardiopulmonary bypass induces a generalized inflammatory reaction accompanied by free radical generation. Depletion of antioxidants could result and is reported for vitamin E and C. We investigated the effect of cardiopulmonary bypass on plasma concentrations of α-tocopherol, retinol, and biochemical variables (e.g., triacylglycerol, cholesterol, and C-reactive protein).

Patients and methods. Plasma levels of all parameters were investigated by serial sampling in ten men undergoing elective coronary artery bypass grafting. Samples were taken before, during, and up to 48 h after bypass to obtain time profiles of the laboratory indices.

Results. α-Tocopherol and retinol decreased during cardiopulmonary bypass when not adjusted for confounders. After adjustment for hemodilution and lipids, no significant change was noted during bypass. However, a reduction in retinol was observed 48 h postoperatively.

Conclusions. These data indicate that vitamin E and A analysis to ascertain links to their consumption via the production of free radicals under conditions of cardiopulmonary bypass may be inappropriate. Specifically, during bypass a reduction in systemic vitamin E and A seems to be a response to changes in blood volume and liver function.