Predicting the unpredictable: unveiling hidden patterns of emergency department unexpected deaths - a retrospective...

Unexpected deaths in the emergency department (ED) are rare but may indicate missed opportunities to detect clinical deterioration. This study aimed to identify risk factors associated with unexpected deaths and to better characterize patients at risk during their ED stay.

A retrospective study was conducted in the two EDs of CHU Liège between 2019 and 2023. All adult deaths (≥16 years) were extracted from the hospital's electronic health records and classified as expected or unexpected based on predefined criteria. Demographic data, triage levels, vital signs, Early Warning Scores (EWS), Glasgow Coma Scale (GCS), care location, and timing of death were analyzed using R software.

Among 461,958 ED admissions, 823 adult patients died. Of these, 42 (5.1%) were classified as unexpected. These cases were more frequently transported by non-medicalized ambulance (40.5% vs. 27.5%, p = 0.006), assigned lower triage levels (p < 0.001), and less often admitted to the resuscitation room (73.8% vs. 49.8%, p = 0.002). They also presented lower EWS (0-4: 77.4% vs. 48.5%, p = 0.006) and higher initial GCS scores (p = 0.002). In multivariate analysis, a high EWS (≥7) and an altered GCS were both associated with a lower likelihood of unexpected death (OR 0.10, p = 0.03, and OR 0.32, p = 0.05, respectively), indicating that these factors were more frequent among expected deaths.

Unexpected deaths represented 5.1% of ED fatalities and were often preceded by subtle signs such as behavioral changes or mildly abnormal vital signs. Many occurred after initial stabilization, particularly in short-stay areas, underscoring the need to reflect on the organization and role of these units within the hospital system.