Study objective: We measured the frequency of unanticipated death among patients discharged from the emergency department (ED) and reviewed these cases for patterns of potential preventable medical error.
Methods: This was a retrospective cohort of ED patients who were discharged to home from an urban tertiary-care facility after their evaluation, with subsequent case review. Subjects were aged 10 years and older, representing 387,334 visits among 186,859 individuals, February 1994 through November 2004. The main outcome was mortality. Deaths were assessed for relatedness to the last ED visit, whether the death was expected, and whether there was possible medical error. Deaths that were unexpected and related to the ED visit were analyzed using grounded theory to identify common themes among these cases. Error cases were identified as a subset of this group.
Results: We identified and reviewed 117 patients, or 30.2 deaths within 7 days of discharge per 100,000 ED discharges home (95% confidence interval [CI] 25.2 to 36.2 deaths). Of the 117 cases, 58 (50%) were unexpected but related to the ED visit and 35 (60%) of these had a possible error. For the unexpected, related group, there were 15.0 deaths within 7 days per 100,000 discharges home (95% CI 11.6 to 19.4 deaths); for the possible error group, there were 9.0 (95% CI 6.5 to 12.6 deaths). Four themes repeatedly emerged: atypical presentation of an unusual problem, chronic disease with decompensation, abnormal vital signs, and mental disability or psychiatric problem or substance abuse that may have made it less likely that the patient would return for worsening symptoms.
Conclusion: Monitoring of death records can identify unanticipated deaths after health care encounters. Further hypothesis-driven research is needed to identify, prevent, or mitigate problems in care and reduce the rate of death after ED visit.