Abstract
INTRODUCTION: Tight glycemic control is essential for optimal outcomes after coronary artery bypass graft (CABG) surgery, regardless of pre-operative diabetes status. The ideal timing for transitioning from intravenous (IV) to subcutaneous (SC) insulin remains unclear. This study addresses this knowledge gap by comparing the effects of early transition (postoperative day 1, POD1) versus delayed transition on glycemic control and patient outcomes after CABG surgery. METHODS: We analyzed data from a single tertiary medical center focusing on patients receiving insulin during their CABG hospitalization between 1 and 31 October 2022. We divided patients into two groups based on their transition timing: (1) Delayed Transition Group, patients transitioned from IV insulin infusion to SC insulin after POD1; and (2) Early Transition Group, patients transitioned on POD1. The primary outcome was the incidence of euglycemia on POD1. Secondary outcomes included rates of maintaining euglycemia from POD1 until POD10 or hospital discharge, hospital length of stay (LOS), ICU LOS, mean glucose levels, rates of hyperglycemia (blood glucose > 180 mg/dL) and hypoglycemia (blood glucose < 70 mg/dL), and rate of restarting IV insulin. Statistical analysis adjusted for BMI and diabetes diagnosis. RESULTS: A total of 394 patients were enrolled, with 68 patients (17.3%) in the delayed-transition group and 326 patients (82.7%) in the early-transition group. Majority of the patients were males (74%), with an average age of 67 ± 9 years. Mean HbA1C and creatinine levels were comparable between the two groups. Patients in the early-transition group experienced a shorter ICU and hospital length of stay compared to the delayed-transition group, without a higher risk of restarting IV insulin. CONCLUSIONS: Early transition from IV insulin drip to SC insulin on POD1 of CABG surgery reduces ICU and hospital LOS without increasing the risk of transitioning back to IV insulin.