936

Abstract

Introduction: Hyperglycemia has been associated with worse outcomes in critically ill patients. The effectiveness of insulin infusions in maintaining glycemic control is well established; however, little is known about glycemic control when insulin is transitioned from the intravenous (IV) to the subcutaneous (SC) route. Hypothesis: Transition from IV to SC insulin is associated with worsening of glycemic control. Methods: A cohort of ICU patients from 2006-2010 was defined as those requiring? 2 days of IV insulin, excluding patients with type I diabetes, parenteral nutrition, readmission within 28 days or oral intake. “IV phase” and “SC phase” were defined as the 48 hours before and after discontinuation of IV insulin. The following variables were collected: mean blood glucose (GlucIV and GlucSC), daily mean IV and SC insulin dose (InsulinIV and InsulinSC), daily mean carbohydrate intake (CHOIV and CHOSC), vasopressor use (VasoIV and VasoSC), steroid use (SteroidIV and SteroidSC), age, gender and BMI. Univariate and multivariate regression were used to test the association between GlucSC and the variables. Results: 462 patients met criteria. Median time on IV insulin was 7 (4-10) days; median age was 64 (51-74) years; mean BMI was 29.4 (±14.5). 29.8% of patients were diabetic. Mean InsulinIV was 41.0 (±24.6) units; mean InsulinSC was 5.0 (±14.2) units. Compared to the “SC phase”, more patients in the “IV phase” were on vasopressors (41.8% vs. 29.4%, p < 0.001) and steroids (24.2% vs. 18.4%, p < 0.001). Carbohydrate intake was higher in the “SC phase” (101.8 [±64.8] vs 109.4 [±62.9] grams, p < 0.01). Mean serum glucose in the SC phase was significantly higher than the IV phase (144.4 [±32.4] vs 120.8 [±19.8], p < 0.001). On multiple linear regression analysis, age, diabetes, InsulinIV, GlucIV, CHOSC and VasoSC were significantly associated with glycemic control in the subcutaneous phase. Conclusions: IV to SC insulin transitioning is associated with worsening in glycemic control. Our study identifies variables associated with this worsening. These findings hold the promise of identifying those who are poor candidates for transition and guidance in designing tailored insulin scales with optimal subcutaneous dosing.