Changes inα-tocopherol and retinol levels during cardiopulmonary bypass correlate with maximal arterial partial pressure of oxygen

Abstract

Cardiopulmonary bypass (CPB) is associated with oxidative stress. This study examined antioxidant levels in adults undergoing CPB surgery and their correlation with clinical variables. Arterial blood samples were obtained from 27 patients undergoing CPB. The time-course variation of vitamin C (spectrofluorimetry), alpha-tocopherol and retinol (HPLC) levels were determined. Plasma vitamin C rose initially but gradually decayed during reperfusion until 60% reduction of baseline values post-surgery. alpha-Tocopherol and retinol were reduced along CPB with post-operative values approximately 25% lower than baseline. No significant changes were found for selenium and glutathione peroxidase. PaO(2) values rose steadily throughout CPB. A correlation existed for alpha-tocopherol and retinol depletion vs maximal PaO(2) throughout CPB but no correlation was found for antioxidant consumption vs duration of ischaemia and reperfusion and hypothermia level. In conclusion, consumption of arterial blood antioxidant vitamins occurs with CPB in relation with PaO(2) levels but not for other clinical variables measured in this study.

Preoperative and postoperative administration of vitamin C in cardiac surgery patients – settings, dosages, duration, and clinical outcomes: a narrative review

“…The pattern of plasma changes in all studies is surprisingly the same even after 2 weeks postoperatively. There is a reduction of plasma vitamin C following cardiopulmonary bypass (CPB), namely more than 50%, 6 h postoperatively, and the lower levels persist for up to 14 days 38 , 73 , 75 , 99 – 101 . Our search retrieved no study in the literature that examines vitamin C levels beyond the 2 weeks postoperatively in CS, neither has examined the effects of a longer-term supplementation in this group of patients.…”