Study objectives: To evaluate the effectiveness and safety of maintaining a target blood glucose concentration of 91-130 mg/dl with a standardized, nurse-managed, intensive insulin infusion protocol outside a study setting, and to determine if a statistically significant favorable effect on morbidity and mortality was achieved.
Design: Retrospective, observational, chart review.
Setting: Medical and surgical intensive care units (ICUs) in a community teaching hospital.
Patients: One hundred forty-three adult patients who received insulin infusions managed at the discretion of the physician over a 1-year period before initiation of the protocol (control group), and 70 patients who received insulin infusions over a 6-month period with infusion dosages titrated by using the protocol (protocol group).
Measurements and main results: Episodes of hypoglycemia, time within target range, mean blood glucose concentration, frequency of measurement, length of ICU stay, duration of mechanical ventilation, and overall mortality were collected. Hypoglycemic episodes were not significantly different between the groups. Blood glucose concentrations were within target range in 34% of all measurements in the protocol group compared with 23% in the control group (p<0.001, relative risk [RR] 1.48, 95% confidence interval [CI] 1.38-1.58). Once target range was reached on one measurement, 43% of concentrations remained in target range in the protocol group compared with 29% in the control group (p<0.001, RR 1.47, 95% CI 1.38-1.56). Frequency of measurements was higher in the protocol group versus control group (p=0.01); however, clinical difference was minimal. Protocol group had lower overall mortality rate (27% [19/70] vs 32% [46/143], p=0.45), reduced mean ICU length of stay (16.7 +/- 10.6 vs 18.4 +/- 16.0 days, p=0.37), and less mechanical ventilation time (16.5 +/- 9.7 vs 17.0 +/- 15.0 days, p=0.79).
Conclusion: The nurse-managed insulin infusion protocol improved glycemic control with minimal hypoglycemic episodes compared with baseline practice. A trend toward decreased mortality, ICU length of stay, sand days of mechanical ventilation was observed. When compared with other published protocols, our insulin protocol displays comparable effectiveness with the use of less-frequent blood glucose measurements.