Serum lactates correlate with mortality after operations for complex congenital heart disease

Background. The objective of this study was to determine whether serum lactate levels predict mortality in children less than 1 year of age who have undergone cardiopulmonary bypass and operations for complex congenital heart disease. Methods. The initial lactate, maximum lactate, and lactate levels at 4 to 6 hours after operation were analyzed for each of 48 children less than 12 months of age who underwent cardiopulmonary bypass. Results. Data were analyzed for the 6 patients who died and the 42 patients who survived. For the patients who died, the initial postoperative serum lactate, maximum lactate, and 4- to 6-hour lactate levels were significantly higher than those in the patients who survived. All patients with an initial lactate less than 7 mmol/L, a maximum lactate less than 9 mmol/L, or a 4- to 6-hour lactate level less than 4 mmol/L survived to hospital discharge. Conclusions. Serum lactate levels may be a useful predictor of mortality in children less than 1 year of age who have undergone cardiopulmonary bypass. An elevation in serum lactate level after a complex operation for congenital heart disease should be taken as a serious indicator of potential mortality. (C) 1997 by The Society of Thoracic Surgeons.