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  • Publication # 13-RA006

Overcrowding in emergency departments increases the risk of preventable medical errors

Emergency Care

A crowded emergency department (ED) can foster an environment where preventable medical errors (PMEs) can occur, suggests a new study. It found that patients seen during the highest crowding periods had more than twofold higher occurrences of PMEs. The researchers used data from the National ED Safety Study to look at the impact of ED crowding on development of PMEs in patients with a heart attack, asthma exacerbation, or dislocated joint that required procedural sedation. A random sample of 533 patients was selected who had visited one of four EDs and were diagnosed with one of the three above conditions. Chart reviews revealed the presence of any PMEs. Each patient was also assigned an ED crowding score based on 10-minute crowding calculations.

At least 1 PME occurred in 46 of the 533 patient visits. Patients with the highest average crowding exposure had more than twofold odds of having a PME compared to patients in the lowest quartile of crowding exposure. Those with a heart attack or joint dislocation had a greater risk of experiencing a PME compared to asthma patients. Most of the medical errors occurred in patients with dislocations requiring procedural sedation. The study was supported in part by the Agency for Healthcare Research and Quality (HS13099).

See "Emergency department crowding and risk of preventable medical errors," by Stephen K. Epstein, M.D., David S. Huckins, M.D., Shan W. Liu, M.D., and others in Internal and Emergency Medicine 7, pp. 173-180, 2012.


Page last reviewed March 2013
Internet Citation: Overcrowding in emergency departments increases the risk of preventable medical errors: Emergency Care. March 2013. Agency for Healthcare Research and Quality, Rockville, MD.


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