Administration of Emergency Medicine
Boarding Inpatients in the Emergency Department Increases Discharged Patient Length of Stay

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Abstract

Background

Boarding of inpatients in the Emergency Department (ED) has been widely recognized as a major contributor to ED crowding and a cause of adverse outcomes. We hypothesize that these deleterious effects extend to those patients who are discharged from the ED by increasing their length of stay (LOS).

Study Objectives

This study investigates the impact of boarding inpatients on the ED LOS of discharged patients.

Methods

This retrospective, observational, cohort study investigated the association between ED boarder burden and discharged patient LOS over a 3-year period in an urban, academic tertiary care ED. Median ED LOS of 179,840 discharged patients was calculated for each quartile of the boarder burden at time of arrival, and Spearman correlation coefficients were used to summarize the relationship. Subgroup analyses were conducted, stratified by patient acuity defined by triage designation, and hour of arrival.

Results

Overall median discharged patient ED LOS increased by boarder burden quartile (205 [95% confidence interval (CI) 203–207], 215 [95% CI 214–217], 221 [95% CI 219–223], and 221 [95% CI 219–223] min, respectively), with a Spearman correlation of 0.25 between daily total boarder burden hours and median LOS. When stratified by patient acuity and hour of arrival (11:00 a.m.–11:00 p.m.), LOS of medium-acuity patients increased significantly by boarder burden quartile (252 [95% CI 247–255], 271 [95% CI 267–275], 285 [95% CI 95% CI 278–289], and 309 [95% CI 305–315] min, respectively) with a Spearman correlation of 0.18.

Conclusion

In this retrospective study, increasing boarder burden was associated with increasing LOS of patients discharged from the ED, with the greatest effect between 11:00 a.m. and 11:00 p.m. on medium-acuity patients. This relationship between LOS and ED capacity limitation by inpatient boarders has important implications, as ED and hospital leadership increasingly focus on ED LOS as a measure of efficiency and throughput.

Introduction

Emergency Department (ED) crowding has been recognized as a national crisis for more than 15 years, and mounting evidence indicates that its myriad negative downstream effects impact the entire process of patient care 1, 2. These include deleterious effects on patient care outcomes and metrics of ED efficiency 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23. In addition, it is now widely accepted that the practice of boarding inpatients in the ED is a significant contributor to ED crowding and the resulting adverse outcomes 24, 25, 26, 27, 28, 29, 30. However, the relationship between boarding inpatients and specific downstream metrics has been less clearly defined to date 26, 30, 31. Further, although ED crowding has been conceptualized in an input/throughput/output model, comprehensive application of operations research and systems science to study the problem has remained somewhat limited, despite the 2006 call for the same from the Institute of Medicine 27, 28.

In this era of worsening ED crowding, the emphasis on ED efficiency metrics is also increasing as ED and hospital administrators seek to improve ED throughput and patient care. One popular measure of ED throughput is the length of stay (LOS) of patients discharged from the ED, in part due to the fact that this measure is not thought to be affected by the same confounders as are present with admitted patients. Yet systems science, including the theory of constraints, would suggest that any bottleneck within the system has an effect on the entire system, and each component part individually. The implications of these relationships are of paramount importance for directing improvement efforts, given the potential upstream and downstream effects of a bottleneck on operational and process flow metrics. Put simply, if the bottleneck of boarding inpatients in the ED (an output process) affects the entire ED system of care, then it should affect the throughput of even those patients who are never admitted.

In this study, we aimed to investigate the effect of boarding hospital inpatients on a specific measure of ED throughput efficiency, namely discharged patient LOS. Drawing on the theory of constraints, we hypothesized that as the number of patients boarding in the ED (boarder burden) increased, the LOS of discharged patients would also increase. We considered a 15-min decrease in median LOS important, and wished to study a sufficient time period such that we could be 95% certain that our result was within 5 min of the true value. We also sought to stratify this relationship by patient acuity and by hour of arrival to better define the relationships and their generalizability to other institutions.

Section snippets

Study Design

This retrospective, observational, cohort study investigated the association between ED boarder burden and discharged patient LOS over a 3-year period (October 2007–September 2010). The period of 3 years was chosen to provide adequate sample size for subgroup analysis and to avoid any seasonal effect. The ED staff and all participants were unaware of the data collection or analysis, as this was a retrospective study. As a quality assurance project examining internal operations and

Results

The total ED census during the study period was 266,934; 179,840 (67.4%) of the patients were treated and released from the ED (Table 1). Among discharged patients, boarder burden at the time of patient arrival was divided into quartiles of 0–4.9 patients, 5.0–8.0 patients, 8.1–11.9 patients, and 12.0–36.0 patients. The median discharged patient ED LOS increased by boarder burden quartile (205 [95% CI 203–207], 215 [95% CI 214–217], 221 [95% CI 219–223], and 221 [95% CI 219–223] min,

Discussion

In this retrospective observational cohort study, the overall LOS of patients discharged from the ED increased by approximately 10% as the boarder burden increased. In subgroup analysis, medium-acuity patients arriving between 11:00 a.m. and 11:00 p.m. (at times of highest boarder burden) could expect a 57-min (23%) longer LOS before discharge. The implications of these findings are significant, and both highlight the overall effect of capacity limitation on an ED and provide guidance with

Conclusions

In this retrospective, single-center study, increasing boarder burden was associated with increasing LOS of patients discharged from the ED, with the greatest effect between 11:00 a.m. and 11:00 p.m. on medium-acuity patients, resulting in a 57-min increase in LOS at times of high boarder burden. This relationship between LOS and ED capacity limitation by inpatient boarders has important implications as ED and hospital leadership increasingly focus on ED LOS as a measure of efficiency and

References (31)

  • B.R. Asplin et al.

    A conceptual model of emergency department crowding

    Ann Emerg Med

    (2003)
  • Hospital-based emergency care: at the breaking point

    (2006)
  • C. Fee et al.

    Effect of emergency department crowding on pneumonia admission care components

    Am J Manag Care

    (2011)
  • P. Chatterjee et al.

    Emergency department crowding and time to care in patients with acute stroke

    Stroke

    (2011)
  • M.R. Sills et al.

    Emergency department crowding is associated with decreased quality of care for children with acute asthma

    Ann Emerg Med

    (2011)
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