Mortality Associated With Emergency Department Boarding Exposure

Background: Emergency Department (ED) boarding threatens patient safety. It is unclear whether boarding differentially affects patients admitted to intensive care units (ICUs) versus non-ICU settings. Research Design and Subjects: We performed a 2-hospital, 18-month, cross-sectional, observational, descriptive study of adult patients admitted from the ED. We used Kaplan-Meier estimation and Cox Proportional Hazards regression to describe differences in boarding time among patients who died during hospitalization versus those who survived, controlling for covariates that could affect mortality risk or boarding exposure, and separately evaluating patients admitted to ICUs versus non-ICU settings. Measures: We extracted age, race, sex, time variables, admission unit, hospital disposition, and Elixhauser comorbidity measures and calculated boarding time for each admitted patient. Results: Among 39,781 admissions from the EDs (21.3% to ICUs), non-ICU patients who died in-hospital had a 1.2-fold risk (95% confidence interval, 1.03–1.36; P=0.016) of having experienced longer boarding times than survivors, accounting for covariates. We did not observe a difference among patients admitted to ICUs. Conclusions: Among non-ICU patients, those who died during hospitalization were more likely to have had incrementally longer boarding exposure than those who survived. This difference was not observed for ICU patients. Boarding risk mitigation strategies focused on ICU patients may have accounted for this difference, but we caution against interpreting that boarding can be safe. Segmentation by patients admitted to ICU versus non-ICU settings in boarding research may be valuable in ensuring that the safety of both groups is considered in hospital flow and boarding care improvements.