Disequilibrium Between Admitted and Discharged Hospitalized Patients Affects Emergency Department Length of Stay
Received 8 January 2009; received in revised form 18 March 2009; accepted 15 April 2009. published online 26 June 2009.
Study objective
Most patients are admitted to the hospital through the emergency department (ED), and ED waiting times partly reflect the availability of inpatient beds. We test whether the balance between daily hospital admissions and discharges affects next-day ED length of stay.
Methods
We conducted a cross-sectional study of hospitals in metropolitan Toronto, served by a single emergency medical services provider in a publicly funded system. During a 3-year period, we evaluated the daily ratio of admissions to discharges at each hospital and the next-day median ED length of stay in the same hospital by using linear regression.
Results
Across hospitals, the daily mean (SD) 50th percentile ED length of stay averaged 218 (51) minutes. As the inpatient admission-discharge ratio increased or decreased, next-day ED length of stay changed accordingly. Compared with ratios of 1.0, those less than 0.6 were associated with an 11-minute (95% confidence interval [CI] 5 to 16 minutes) shorter next-day median ED length of stay; at admission-discharge ratios of 1.3 to 1.4, ED length of stay was significantly prolonged by 5 minutes (95% CI 3 to 6 minutes). Admission-discharge ratios on weekends and among medical inpatients had a stronger influence on next-day ED length of stay; effects were also greater among higher-acuity and admitted ED patients.
Conclusion
Disequilibrium between the number of admitted and discharged inpatients significantly affects next-day ED length of stay. Better matching of daily hospital discharges and admissions could reduce ED waiting times and may be more amenable to intervention than reducing admissions alone. The admission-discharge ratio may also provide a simple way of tracking and enhancing hospital system performance.
aInstitute for Clinical Evaluative Sciences, Toronto, Ontario, Canada
bDepartment of Health Policy, Management and Evaluation, University of Toronto, Toronto, Ontario, Canada
cDepartment of Medicine, University of Toronto, Toronto, Ontario, Canada
dScholarship in Surgery Program, University of Toronto, Toronto, Ontario, Canada
eDepartment of Emergency Services, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
fClinical Epidemiology Unit, Sunnybrook Health Sciences Centre, Toronto, Ontario, Canada
Funding and support: By Annals policy, all authors are required to disclose any and all commercial, financial, and other relationships in any way related to the subject of this article that might create any potential conflict of interest. See the Manuscript Submission Agreement in this issue for examples of specific conflicts covered by this statement. Supported by a grant from the Peter Lougheed Medical Research Foundation. Drs. Ray and Bell are supported by Canadian Institutes for Health Research New Investigator Awards.
Supervising editor: Donald M. Yealy, MD
Author contributions: MJV, JGR, CB, BC, and MJS participated in the design of the study. TAS took primary responsibility for the design of the analysis. All authors contributed to the article and take responsibility for the content. MJV and MJS take responsibility for the paper as a whole.
ABSTRACT