Insulin Therapy in Hospitalized Patients

Background: Hyperglycemia is prevalent and is associated with an increase in morbidity and mortality in hospitalized patients. Insulin therapy is the most appropriate method for controlling glycemia in hospital, but is associated with increased risk of hypoglycemia, which is a barrier to achieving glycemic goals.

Areas Of Uncertainty: Optimal glycemic targets have not been established in the critical and noncritical hospitalized patients, and there are different modalities of insulin therapy. The primary purpose of this review is to discuss controversy regarding appropriate glycemic targets and summarize the evidence about the safety and efficacy of insulin therapy in critical and noncritical care settings.

Data Sources: A literature search was conducted through PubMed with the following key words (inpatient hyperglycemia, inpatient diabetes, glycemic control AND critically or non-critically ill patient, Insulin therapy in hospital).

Results: In critically ill patient, blood glucose levels >180 mg/dL may increase the risk of hospital complications, and blood glucose levels <110 mg/dL have been associated with an increased risk of hypoglycemia. Continuous intravenous insulin infusion is the best method for achieving glycemic targets in the critically ill patient. The ideal glucose goals for noncritically ill patients remain undefined and must be individualized according to the characteristics of the patients. A basal-bolus insulin strategy resulted in better glycemic control than sliding scale insulin and lower risk of hypoglycemia than premixed insulin regimen.

Conclusions: Extremes of blood glucose lead to poor outcomes, and target glucose range of 110-180 mg/dL may be appropriate for most critically ill patients and noncritically ill patients. Insulin is the most appropriate pharmacologic agent for effectively controlling glycemia in hospital. A continuous intravenous insulin infusion and scheduled basal-bolus-correction insulin are the preferred modalities for glycemic control in critically and noncritically ill hospitalized patients, respectively.