Postoperative management of diabetes mellitus: steady-state glucose control with bedside algorithm for insulin adjustment

Abstract

An algorithm was developed to determine whether an individualized insulin infusion could maintain plasma glucose in a desirable steady state after surgery. In 24 patients, insulin was provided according to a "glucose-feedback" formula to maintain plasma glucose between 120 and 180 mg/dl (6.7-10.0 mM). Initial plasma glucose was elevated, 218 +/- 16 mg/dl (mean +/- SE 12.1 +/- 0.9 mM), but reached the target range after 8 h and remained steady for the rest of the study period. Insulin requirements varied considerably, 0.5-5.0 U/h. Infusion rates were correlated with initial plasma glucose but not with previous insulin dose, HbA1c, or percent ideal body weight. Although insulin needs cannot be predicted, plasma glucose can be maintained in a desirable range after surgery via a simple formula suitable for implementation by general ward nurses.