Tight Glucose Control in Critically Ill Adults
Wiener RS, Wiener DC, Larson RJ
JAMA. 2008;300:933-944

Over the past 5 years, an increasing number of healthcare groups, such as the American Diabetes Association and the Surviving Sepsis Campaign, have promulgated the implementation of tight glycemic control (serum glucose 80-110 mg/dL) in critically ill adult patients. These recommendations are primarily based on 1 large trial in surgical patients, whereas other studies have shown lesser or no efficacy. The authors of this study sought to determine the efficacy and safety of tight glycemic control in critically ill adult patients, with a focus on adverse event, particularly hypoglycemia. They analyzed 29 published trials that included 8432 critically ill adult patients and found no difference in rate of mortality or renal failure. There was an approximate 25% reduction in hospital-acquired sepsis, but there was a 5-fold increased risk for hypoglycemia. On the basis of these results, the authors concluded that tight glycemic control does not confer benefit for broad populations of critically ill adults and is associated with a greater risk for hypoglycemia.

Viewpoint

The first significant publication of improved clinical outcomes with tight glycemic control sparked an international movement toward tight glucose control in many groups of critically ill patients (ie, adults in medical and surgical units, children, and neonates). Since that seminal publication, other studies, including another by the same authors, failed to show similar benefits. More important, many of those studies questioned the efficacy of tight glycemic control based on the risk:benefit ratio, particularly the adverse consequences of hypoglycemia. This meta-analysis supports the contention of a growing number of physicians that tight glycemic control is not an appropriate strategy in critically ill adults. Surgical patients may derive benefit from such a strategy, although this may be due to "glucose clamping" with combined infusion of glucose and insulin to achieve safe and effective glycemic control in a tight range. The same benefit almost certainly does not exist for nonsurgical patients; in fact, tight glycemic control may cause more harm than benefit. In addition, we do not fully understand all of the consequences of hypoglycemia, aside from the immediate effects on neurologic function. Until better evidence emerges for the safety and efficacy of tight glucose control in critically ill adults, glucose control strategies should be applied primarily to prevent severe hyperglycemia.

Abstract