The 4-hour target in the emergency department, in-hospital mortality, and length of hospitalization: A single center-retrospective study.

Abstract

The four-hour (4 h') rule in the emergency department (ED) is a performance-based measure introduced with the objective to improve the quality of care. We evaluated the association between time in the ED with in-hospital mortality and hospital length of stay (LOS). This was a retrospective study performed in one public hospital with over 100,000 ED referrals per year. Hospitalizations from the ED during 2017 were analyzed. We defined time in the ED as either: until a decision was made (DED); or total time in the ED (TED). In-hospital mortality and LOS were evaluated for patients with DED or TED within and beyond 4 h'. Compared to patients with TED or DED within 4 h', in-hospital mortality did not increase in patients with TED beyond 4 h' (2.8% vs. 3.1%, non-significant), or DED beyond 4 h' (2.1% vs. 3.2%, p < 0.001). LOS did increase in patients with either DED or TED beyond 4 h' (p < 0.001). In-hospital mortality increased with increasing DED-TED intervals for patients hospitalized in the internal medicine departments: 3.7% (0-1 h'), 5.1% (1-2 h'), 5.7% (2-3 h'), and 7.1% (>3 h') (p < 0.001). In-hospital mortality was not associated with time in the ED beyond 4 h'. LOS, however, was increased in this group of patients. Decreased LOS observed in patients with time in the ED within 4 h', does not support patients' risk as a contributing factor leading to higher trends in mortality observed in this patient group. In-hospital mortality was associated with an increase in DED-TED intervals in patients hospitalized in the internal medicine departments.