Examination of Implementation of Intravenous and Subcutaneous Insulin Protocols and Glycemic Control in Heart Transplant Patients

Abstract

Perioperative glycemic management is particularly challenging in heart transplant (HT) patients who are on high-dose steroids and subject to surgical stress. The objective of the study was to examine the efficacy and safety of perioperative insulin administration in HT patients with and without diabetes. Medical records of 71 HT patients from June 1, 2005 to July 31, 2009 whose hyperglycemia was managed by our Glucose Management Service (GMS) were analyzed for up to 1 year after HT. Their daily blood glucose (BG) averages on intravenous (i.v.) insulin drips and subcutaneous (s.q.) insulin, hypoglycemia rates, reasons for hypoglycemia, and deviations from insulin protocols were analyzed. Daily BG averages between diabetic (DM) and nondiabetic (nonDM) patients were not significantly different while on the drip but were significantly different for first 5 days on s.q. (P<.05). The daily insulin glargine doses were similar. No patients developed severe hypoglycemia (BG ≤40 mg/dL) while on drip, and only 2.8% experienced hypoglycemia on s.q. Among 40 episodes of moderate hypoglycemia while on drip, 15 had nurse deviations from protocol prior to the episode. Posttransition day fasting glucose was at goal (mean 124.7 ± 35.4 mg/dL); however 39.4% (28/71) of patients received a transition insulin glargine dose that was different from the amount indicated by protocol. The likelihood of developing moderate hypoglycemia on s.q. was associated with the glargine dose used at the time of transition (odds ratio [OR] 1.03, P = .034). Inpatient insulin protocols implemented by a GMS are successful in obtaining glycemic control with minimal side effects in patients with and without diabetes, even when they are on a high-dose steroid regimen.