Concept and development of a discharge alert filter for abnormal laboratory values coupled with computerized provider order entry: A tool for quality improvement and hospital risk management

Purpose: To develop a clinical decision support system activated at the time of discharge to reduce potentially inappropriate discharges from unidentified or unaddressed abnormal laboratory values. Methods: We identified 106 laboratory tests for possible inclusion in the discharge alert filter. We selected 7 labs as widely available, commonly obtained, and associated with high risk for potential morbidity or mortality within abnormal ranges. We identified trigger thresholds at levels that would capture significant laboratory abnormalities while avoiding excessive flag generation because of laboratory results that minimally deviate outside the normal reference range. Results: We selected sodium (>155 or <125 mmol/L), potassium (<2.5 or >6 mEq/dL) phosphorous (<1.6 mg/dL), magnesium (<1.2 mg/dL), creatinine greater than 1.1 with a rise of 20% or more between the 2 most recent results, white blood cell count (>11,000 cells/mm with a rise of 20% or more between the 2 most recent results), and international normalized ratio greater than 4. Conclusions: A discharge alert filter that reliably and effectively identifies patients that may be discharged in unsafe situations because of unaddressed critical laboratory values can improve patient safety at discharge and potentially reduce the incidence of costly litigation. Further research is needed to validate whether the proposed discharge alert filter is effective at improving patient safety at discharge.