Perioperative Glycemic Control: An Evidence-based Review

Hyperglycemia in perioperative patients has been identified as a risk factor for morbidity and mortality. Intensive insulin therapy (IIT) has been shown to reduce morbidity and mortality among the critically ill, decrease infection rates and improve survival after cardiac surgery, and improve outcomes in acute neurologic injury and acute myocardial infarction. However, recent evidence of severe hypoglycemia and adverse events associated with IIT brings its safety and efficacy into question. In this article, we summarize the mechanisms and rationale of hyperglycemia and IIT, review the evidence behind the use of IIT in the perioperative period, and discuss the implications of including glycemic control in national quality benchmarks. We conclude that while avoidance of hyperglycemia is clearly beneficial, the appropriate glucose target and specific subpopulations who might benefit from IIT have yet to be identified. Given the potential for harm, inclusion of glucose targets in national quality benchmarks is premature.