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

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 alpha-tocopherol, retinol, and biochemical variables (e.g., triacylglycerol, cholesterol, and C-reactive protein).

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.

alpha-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.

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.