Inpatient insulin therapy

Background: Many diabetic, as well as nondiabetic, hospitalized patients develop hyperglycemia. Numerous studies have demonstrated that critically ill, as well as noncritically ill, hospitalized patients who develop hyperglycemia are at increased risk for morbidity and mortality.

Objective: The objective of this article was to review the risks associated with hyperglycemia in hospitalized patients, the biologic rationale for using insulin to prevent increases in glucose levels, and strategies for managing hyperglycemia in the hospital setting.

Methods: We conducted a computerized search of biomedical journal literature from MEDLINE, PubMed, and Ovid published from 1994 to March 2008. We reviewed English-language original and review articles found under the subject headings “hospitalization and insulin therapy,” “inpatient diabetes and complications,” and “insulin and inflammation.”

Results: More than 200 references were found during the literature search. According to the literature, the adverse outcomes that are associated with hyperglycemia may be attributed to the inflammatory and pro-oxidant effects of elevated glucose levels. The use of insulin, which has anti-inflammatory, vasodilatory, and antioxidant properties as well as the ability to inhibit lipolysis and platelet aggregation, can prevent many of these adverse outcomes.

Conclusions: Hospitals should have protocols in place for using insulin to treat and prevent hyperglycemia. Subcutaneous insulin may be used for both purposes in most noncritically ill patients, whereas intravenous infusion of insulin is preferred in critically ill patients.