The effect of hospital occupancy on emergency department length of stay and patient disposition.

Emergency department (ED) overcrowding is a common problem. Despite a widespread belief that low hospital bed availability contributes to ED overcrowding, there are few data demonstrating this effect. Objectives: To identify the effect of hospital occupancy on ED length of stay for admitted patients and patient disposition. Methods: This was an observational study design using administrative data at a 500-bed acute care teaching hospital. All patients presenting to the ED between April 1993 and June 1999 were included in the study. The predictor variable was daily hospital occupancy. Outcome measures included daily ED length of stay for admitted patients, daily consultation rate, and daily admission rate. The models controlled for the average daily age of ED patients and the average daily “arrival density” index, which adjusts for patient volume and clustering of patient arrivals. Results: The average hospital occupancy was 89.7%. On average 155 patients visited the ED daily; 21% were referred to hospital physicians and 19% were admitted. The median ED length of stay for admitted patients was 5 hours 54 minutes (interquartile range 5 hr 12 min to 6 hr 42 min). Daily ED length of stay for admitted patients increased 18 minutes (95% CI = 12 to 24) when there was an absolute increase in occupancy of 10%. The ED length of stay appeared to increase extensively when hospital occupancy exceeded a threshold of 90%. Consultation and admission rates were not influenced by hospital occupancy. Conclusions: Increased hospital occupancy is strongly associated with ED length of stay for admitted patients. Increasing hospital bed availability might reduce ED overcrowding.

[1]  Donald A Redelmeier,et al.  Urban emergency department overcrowding: defining the problem and eliminating misconceptions. , 2002, CJEM.

[2]  A. Kellermann,et al.  Emergency departments and crowding in United States teaching hospitals. , 1991, Annals of emergency medicine.

[3]  J K Cooper,et al.  Estimating bed needs by means of queuing theory. , 1974, The New England journal of medicine.

[4]  D. Kleinbaum,et al.  Applied regression analysis and other multivariable methods, 3rd ed. , 1998 .

[5]  J. Richards,et al.  Overcrowding in the nation's emergency departments: complex causes and disturbing effects. , 2000, Annals of emergency medicine.

[6]  N. Gibbs.  "Do you want to die?" The crisis in emergency care is taking its toll on doctors, nurses--and patients. , 1990, Time.

[7]  M. Henry,et al.  Overcrowding in America's emergency departments: inpatient wards replace emergency care. , 2001, Academic emergency medicine : official journal of the Society for Academic Emergency Medicine.

[8]  J. Posnett,et al.  Dynamics of bed use in accommodating emergency admissions: stochastic simulation model , 1999, BMJ.

[9]  Mcquarrie Dg,et al.  Hospitalization utilization levels. The application of queuing. Theory to a controversial medical economic problem. , 1983 .

[10]  Ò. Miró,et al.  Decreased health care quality associated with emergency department overcrowding. , 1999, European journal of emergency medicine : official journal of the European Society for Emergency Medicine.

[11]  M Tavakoli,et al.  Referral rates and waiting lists: some empirical evidence. , 1998, Health economics.

[12]  R. Kravitz,et al.  Frequent overcrowding in U.S. emergency departments. , 2001, Academic emergency medicine : official journal of the Society for Academic Emergency Medicine.

[13]  D A Redelmeier,et al.  Emergency department overcrowding following systematic hospital restructuring: trends at twenty hospitals over ten years. , 2001, Academic emergency medicine : official journal of the Society for Academic Emergency Medicine.

[14]  E J Orav,et al.  Determinants of patient satisfaction and willingness to return with emergency care. , 2000, Annals of emergency medicine.

[15]  A. Kellermann,et al.  Critical decision making: managing the emergency department in an overcrowded hospital. , 1991, Annals of emergency medicine.

[16]  G. Box,et al.  On a measure of lack of fit in time series models , 1978 .

[17]  E. Fisher,et al.  Hospital readmission rates for cohorts of Medicare beneficiaries in Boston and New Haven. , 1994, The New England journal of medicine.

[18]  N. Roos,et al.  Predicting Hospital Utilization by the Elderly: The Importance of Patient, Physician, and Hospital Characteristics , 1989, Medical care.

[19]  P. Krochmal,et al.  Increased health care costs associated with ED overcrowding. , 1994, The American journal of emergency medicine.

[20]  N. Roos,et al.  Hospitalization style of physicians in Manitoba: the disturbing lack of logic in medical practice. , 1992, Health services research.

[21]  J. Mccabe,et al.  Emergency department overcrowding: a national crisis. , 2001, Academic medicine : journal of the Association of American Medical Colleges.