Outcomes and adverse effects of extremely high dose insulin infusions in ICU patients

Describe the characteristics, hospital course, and outcomes of adult ICU patients receiving extremely high dose insulin infusions compared to those with lower insulin requirements.

Retrospective observational study of 128 adult ICU patients receiving IV insulin infusions at a large academic medical center. Extremely high dose insulin infusions were defined as maximum rate ≥ 35 units/h. The primary endpoint was rate of hypoglycemia (BG < 70 mg/dL) and time to glucose control. A post-hoc matching analysis was performed for baseline imbalances.

Analysis included 32 patents with extremely high dose insulin infusions and 96 patients without, and most had a goal BG 100-150 mg/dL. Patients in the extreme group were more likely to have type 2 diabetes, a higher median hemoglobin A1c, preadmission insulin, be admitted for a medical reason, and receive inpatient steroids. The extreme group were more likely to experience hypoglycemia (<70 mg/dL, 63% v. 34%, p = 0.005), longer time to glucose control (19.8 h v. 5.7 h, p < 0.001) and higher mortality (34% v. 15%, p = 0.014).

ICU patients with extremely high dose insulin infusions had more hypoglycemia and took longer to achieve glucose targets compared to those with lower requirements. An individualized approach may be required for appropriate management.