Author:

Keywords:

blood glucose, critical illness polyneuropathy, glycemic control, insulin, intensive insulin therapy, morbidity, mortality, Endocrinology & Metabolism, 1103 Clinical Sciences, 1117 Public Health and Health Services, 1302 Curriculum and Pedagogy

Abstract:

There is a high risk of mortality or significant morbidity among patients who require intensive hospital care for >5 days due to sepsis, critical illness polyneuropathy and multiple organ failure. Many patients in the intensive care unit (ICU) are hyperglycemic, which, until recently, was presumed to reflect the adaptive development of insulin resistance. However, in a recent study of a large group of patients (n=1548) receiving mechanical ventilation in the ICU after surgery, the author and colleagues demonstrated that the occurrence of hyperglycemia in the ICU was not a beneficial adaptation to severe illness but instead predisposed patients to many of the typical complications in the ICU, prolonged ICU stay and death. They further demonstrated that intensive insulin therapy (IIT) using continuous insulin infusion tailored to achieve and maintain blood glucose (BG) levels in the range of 4.4 mmol/L to 6.1 mmol/L during critical illness improved patient outcomes. The use of IIT resulted in a 43% reduction in the risk of mortality in the ICU and a 34% reduction in the risk of in-hospital mortality compared to conventional therapy. A reduced risk of severe infection in those treated with IIT vs. those who received conventional therapy was reflected by a 46% reduction in bacteremia and a 35% reduction in the need for prolonged antibiotic therapy. Excessive inflammation was also reduced by IIT, independent of its effect on severe infections. Glycemic control, rather than insulin administration, appears to explain the clinical benefits observed, as shown through multivariate logistic regression analysis. An algorithm used to achieve and maintain normoglycemia in patients in the ICU who have undergone surgery is proposed for implementation into clinical practice in patient populations similar to those included in the Leuven study. Further data are required to determine if this strategy is applicable to other groups of patients in the ICU and in the general hospital setting.