Role of Blood Lactate Levels in Predicting Morbidity and Mortality Outcomes Following Cardiac Surgeries

BACKGROUND lactate is a product of anaerobic metabolism. Tissue hypoxia because of hypo perfusion or impaired oxygen extraction rise in blood lactate levels. An elevated blood lactate level has been postulated as a marker for adverse outcomes and mortality risk in patients undergoing cardiac surgery under cardiopulmonary bypass (CPB). This study was carried out evaluate the association between blood lactate levels and mortality following cardiac surgery. retrospective record-based cross-sectional study was carried out among 503 patients who underwent cardiac surgery under . Apart from baseline lactate value, serum lactate was measured every thirty minutes during CPB (CPBL1, CPBL2, CPBL3 so on) and during post-operative period (POL1, POL2, POL3 and so on). Duration of the CPB, lowest temperature attained the CPB, duration of mechanical ventilation, IABP usage, maximum number of inotropes and vasopressors used and in the peri-operative period were noted. incidence of mortality in this study was 2.2%. Blood Lactate levels were high in the third measurement during CPB (CPBL3) for all the post-operative measurements among those who did not survive. There was a significant association between levels and intra operative lowest temperatures (p<0.05). levels during CPB and post-operative period can be used as a predictor of increased mortality and morbidity. Prolonged and deeper levels of hypothermia is associated with increased lactate levels.