Does Tight Blood Glucose Control during Cardiac Surgery Improve Patient Outcome?

Intensive insulin therapy to maintain normal levels ofblood glucose (4.4 to 6.1mmol/L [80 to 110 mg/dL]) during intensive care improves survival and reduces mor-bidity of critically ill patients after complicated, high-risk, or extensive surgery or trauma (1). Clear benefit from this intervention requires maintenance of tight blood glucose control for at least a few days (2). The mechanism by which maintaining normoglycemia prevents adverse out-comes is not fully understood. One possibility is that avoiding sustained cellular glucose overload and toxicity in certain cell types reduces the likelihood for vital organ dys-function (3). Avoiding glucose toxicity seems to prevent damage to the mitochondrion, the organelle that generates energy for cellular functions (4). The first observation of this clinical effect took place in a randomized trial performed in Belgium (1) in which