Accuracy of a Risk Alert Threshold for ICU Hypoglycemia: Retrospective Analysis of Alert Performance and Association with Clinical Deterioration Events

AbstractObjectiveTo quantify the accuracy of and clinical events associated with a risk alert threshold for impending hypoglycemia during ICU admissions.DesignRetrospective electronic health record review of clinical events occurring ≥1 and ≤12 hours after the hypoglycemia risk alert threshold was met.SettingAdult ICU admissions from June 2020 through April 2021 at the University of Virginia Medical Center.Patients342 critically-ill adults that were 63.5% male with median age 60.8 years, median weight 79.1 kg, and median body mass index of 27.5 kg/m2.InterventionsReal-world testing of our validated predictive model as a clinical decision support tool for ICU hypoglycemia.Measurements and Main ResultsWe retrospectively reviewed 350 hypothetical alerts that met inclusion criteria for analysis. The alerts correctly predicted 48 cases of Level 1 hypoglycemia that occurred ≥1 and ≤12 hours after the alert threshold was met (positive predictive value= 13.7%). Twenty-one of these 48 cases (43.8%) involved Level 2 hypoglycemia. Notably, three myocardial infarctions, one medical emergency team call, two initiations of cardiopulmonary resuscitation, 6 unplanned surgeries, 19 deaths, 20 arrhythmias, and 38 blood or urine cultures were identified or obtained ≥1 and ≤12 hours after an alert threshold was met. Alerts identified 102 total events of hypoglycemia and/or clinical deterioration, yielding a positive predictive value for any event of 29.1%.ConclusionsAlerts generated by a validated ICU hypoglycemia prediction model had positive predictive value of 29.1% for hypoglycemia and other associated adverse clinical events.Key PointsQuestionWhat are the accuracy of and clinical events associated with a risk alert threshold for ICU hypoglycemia?FindingsWe retrospectively reviewed 350 hypothetical alerts that correctly predicted 48 cases of Level 1 hypoglycemia occurring ≥1 and ≤12 hours after the alert threshold was met (positive predictive value= 13.7%). Notably, three myocardial infarctions, one medical emergency team call, two initiations of cardiopulmonary resuscitation, 6 unplanned surgeries, 19 deaths, 20 arrhythmias, and 38 blood or urine cultures were identified or obtained ≥1 and ≤12 hours after an alert threshold was met.MeaningAlerts generated by a validated ICU hypoglycemia prediction model had positive predictive value of 29.1% for hypoglycemia and other associated adverse clinical events.