Adverse Events Related to Emergency Department Care: A Systematic Review

Objective
To systematically review the literature regarding the prevalence, preventability, severity and types of adverse events (AE) in the Emergency Department (ED).
Methods
We systematically searched major bibliographic databases, relevant journals and conference proceedings, and completed reference reviews of primary articles. Observational studies (cohort and case-control), quasi-experimental (e.g. before/after) studies and randomized controlled trials, were considered for inclusion if they examined a broad demographic group reflecting a significant proportion of ED patients and described the proportion of AE. Studies conducted outside of the ED setting, those examining only a subpopulation of patients (e.g. a specific entrance complaint or receiving a specific intervention), or examining only adverse drug events, were excluded. Two independent reviewers assessed study eligibility, completed data extraction, and assessed study quality with the Newcastle Ottawa Scale.
Results
Our search identified 11,624 citations. Ten articles, representing eight observational studies, were included. Methodological quality was low to moderate with weaknesses in study group comparability, follow-up, and outcome ascertainment and reporting. There was substantial variation in the proportion of patients with AE related to ED care, ranging from 0.16% (n = 9308) to 6.0% (n = 399). Similarly, the reported preventability of AE ranged from 36% (n = 250) to 71% (n = 24). The most common types of events were related to management (3 studies), diagnosis (2 studies) and medication (2 studies).
Conclusions
The variability in findings and lack of high quality studies on AE in the high risk ED setting highlights the need for research in this area. Further studies with rigorous, standardized outcome assessment and reporting are required.