Effects of peri-operative glucose levels on adverse outcomes in infants receiving open-heart surgery for congenital heart disease with cardiopulmonary bypass

Abstract

Studies designed to evaluate the association of hyperglycemia and adverse events in pediatric patients receiving open cardiac surgery have yielded inconsistent results. The aim of this retrospective, observational study was to evaluate the effects of peri-operative glucose levels on adverse events in infants receiving open-heart surgery with CPB. From Nov 2009 through Dec 2009, 100 infants undergoing open-heart surgery were enrolled. All glucose values during the operation and intensive care unit stay were documented. Metrics of glucose control, including mean, peak and minimum glucose levels were calculated. Hyperglycemia was defined as a mean glucose above 150 mg/dl. Hypoglycemia was defined as minimum glucose below 65 mg/dl. Multivariable regression analyses were used to determine relationships between these metrics of glucose control and a composite morbidity-mortality outcome after controlling for multiple variables known to influence early outcomes after congenital heart surgery. According to our definition, 43 patients (43%) developed hyperglycemia and 9 patients (9%) developed at least one episode of hypoglycemia. A total of 58 patients reached the overall composite morbidity-mortality end point at some point during the study period. After adjusting the effects of age, cross-clamp time and pre-operative percutaneous oxygen saturation by multivariable analysis, euglycemia, defined as mean glucose ≤150 mg/dl, was found to be a significant predictor for morbidity, with an odds ratio of 5.1(95% confidence interval 1.5-17.5). In contrast to adult critically ill patients, data from the present study did not prove that hyperglycemia was detrimental to infants receiving open-heart surgery with CPB. The existing literature and findings of our present study warranted future clinical studies of strict glycemic control in critically ill children, considering a more permissive glycemic range as a desirable target.