Hyperglycemia and nutrition support: theory and practice.

Hyperglycemia has long been known to portend a worse short-term prognosis than euglycemia in hospitalized patients. Hyperglycemia reflects illness severity and results in deleterious consequences for certain patient groups. In a surgical intensive care unit population, normalization of morning glucose values using insulin infusions improved mortality vs controls. Until additional studies in other patient groups are reported, practitioners of nutrition support must prevent excessive iatrogenic hyperglycemia, in particular when using parenteral feeding, and should choose aggressive glycemic goals that also avoid hypoglycemia.