Efficacy and safety of three insulin protocols in medical critically ill patients

INTRODUCTION: Strict glycemic control has been recommended for critically ill patients. However, its implementation may face difficulties with increased nursing workload, inadequate blood glucose control and higher risk of hypoglycemia. OBJECTIVES: To evaluate the efficacy and safety of three insulin protocols in medical ICU patients (MICU). METHODS: MICU patients with at least one blood glucose of at least 150 mg/dL and one or more of the following characteristics were included: mechanical ventilation; at least three criteria for systemic inflammatory response syndrome; admitted because of trauma or burn. Patients were randomized to one of the following treatments: protocol A - continuous insulin infusion with adjustments guided by handheld device or desktop software targeting blood glucose levels between 100mg/dL-130mg/dL; protocol B continuous insulin aiming blood glucose levels between 80mg/dl-110mg/dl; protocol C conventional treatment intermittent subcutaneous administration of insulin if blood glucose levels exceeded 150mg/dL. Efficacy was measured by the mean of patients median blood glucose and safety was measured by the incidence of hypoglycemia (40 mg/dL). RESULTS: 167 patients were included. Mean and standard deviation of patients median blood glucose was 125.0±17.7 mg/dl, 127.1±32.2mg/dl and 158.5±49.6 mg/dl for protocols A, B and C, respectively (P<0.001 for all protocol comparison; P=0.34 for protocol A versus B). 12 patients (21,4%) evolved with at least one episode of hypoglycemia in protocol A, 24 (41.4%) in protocol B, and 2(3.8%) in protocol C (P<0.001 for all protocol comparison; P=0.02 for protocol A versus B). There were no differences regarding mortality or other clinical outcome, except for a marginal difference on the number of days on norepinephrine (C < A < B). CONCLUSIONS: A computer guided insulin infusion protocol protocol A causes less episodes of hypoglycemia than and is as efficacious as the standard strict glycemic control...