Skip to main content
Archives of Academic Emergency Medicine logoLink to Archives of Academic Emergency Medicine
. 2019 Aug 28;7(1):e52.

Outcomes of Crowding in Emergency Departments; a Systematic Review

Hamid Reza Rasouli 1, Ali Aliakbar Esfahani 2, Mohammad Nobakht 2, Mohsen Eskandari 2, Sardollah Mahmoodi 1, Hassan Goodarzi 1, Mohsen Abbasi Farajzadeh 2,*
PMCID: PMC6785211  PMID: 31602435

Abstract

Introduction:

Emergency Department (ED) crowding is a global public health phenomenon affecting access and quality of care. In this study, we seek to conduct a systematic review concerning the challenges and outcomes of ED crowding.

Methods:

This systematic review utilized original research articles published from 1st January 2007, to 1st January 2019. Relevant articles from the PubMed (MEDLINE), EMBASE, and Google scholar databases were extracted using predesigned keywords. Following the PRISMA guidelines, two reviewers independently evaluated the quality of the studies using Critical Appraisal Skills Programme for cohort studies and qualitative studies, and Joanna Briggs Institute Meta-Analysis of Statistics Assessment and Review Instrument for studies.

Results:

Out of the total of 73 articles in the final record, we excluded 15 of them because of poor quality. This systematic review synthesized the reports of 58 original articles. The outcomes of multiple individual patients and healthcare-related challenges are comprehensively assessed.

Conclusions:

ED crowding affects individual patients, healthcare systems and communities at large. The negative influences of crowding on healthcare service delivery result in delayed service delivery, poor quality care, and inefficiency; all negatively affecting the emergency patients' healthcare outcomes, in turn.

Key Words: Crowding, outcome assessment, emergency service, hospital, systematic review

Introduction

The requirement of emergency healthcare service is an ongoing issue (1). The emergency department (ED) is expected not only to provide emergency care to patients but also to fulfill the needs of the providers, and the communities at large. Besides, the emergency department might be the only source of healthcare services to people especially in rural communities (1, 2).

Evidence shows an increase in emergency healthcare service utilization because of the increased rates of accidental injuries. However, the capacity of the emergency healthcare systems has not been well developed to respond to such high demand because creating a balance between emergency services and the required resources is challenging, especially in under-resourced countries (3-5). This condition leads to crowding of the EDs, which in turn impose public health challenges related to quality of healthcare and outcomes. Crowding is a situation when an identified need for emergency healthcare services exceeds the available resources to provide emergency care to patients within an appropriate time frame (1, 3, 6).

Crowding of the ED leads to adverse outcomes for the patients, providers, the healthcare system and the community. Delay in service provision to patients not only can compromise the quality of the emergency services but can also worsen their consequences. Crowding of the ED might also lead to the violations of the norms and the service provision standards, which in turn might result in patients leaving the facilities without getting the required services. Thus, this systematic review aims to describe the consequences of ED crowding for emergency patients, emergency care providers, and healthcare systems. The findings are anticipated to provide inputs to decision-makers for a better understanding of the effects of ED crowding and to contextualize practical solutions to improve the quality of medical emergency services.

Methods

Search Strategy

In this review, we adopted the definition for “crowding” from the American College of Emergency Physicians which states “Crowding occurs when the identified need for emergency services exceeds available resources for patient care in the emergency department, hospital, or both.” Then, we searched for articles related to crowding in EDs and its major outcomes published in English between January 1, 2007, and January 1, 2019, in PubMed (MEDLINE) and Embase electronic databases. We applied search terms based on common keywords in the literature concerning the consequences of emergency department crowding (Table 1). We used suitable combinations of "OR" and "AND" in all databases. Also, we searched Google scholar and Google to find relevant papers.

Table 1.

Keywords used for searching published articles in databases

Emergency department related concepts
Crowding related concepts
Outcome related concepts
Controlled phrases Keywords Controlled term/phrase Keywords Keywords
PubMed emergency medicine, pediatric emergency medicine, hospital emergency service, emergency medical services emergency, emergency medicine, pediatric emergency medicine, emergency medical services, emergency room,
hospital emergency services,
emergency health services, emergency department, emergency ward, ER, ED
crowding crowding, overcrowded, crowded overcrowding, divert, diversion, congestion, surged, surging, capacity, crises, crisis, occupancy, hospital bed utilization, bed, utilization Left without being seen (LWBS), Length of stay (LOS), delayed treatment, satisfaction, adverse events mortality, morbidity, error, hospitalization, quality, performance, readmissions, overutilization, efficiency, cost
EMBASE emergency ward, emergency medicine crowding,
hospital bed utilization

Data collection and quality assessment

Two reviewers (HR.R. & A.AE.), independently screened the titles, abstracts and the methodological validity of the records using data extraction format before their inclusion in the final review. Discussions with the senior author (M.E) were used to resolve any disagreements among the reviewers during the assessment phase.

The inclusion criterion was: All studies evaluating the effects and consequences of ED crowding. However, a study was excluded if it only reported the outcomes of a case report or systematic review investigations.

A total of 73 articles were eligible for the review (Figure 1). We further assessed the records using the standardized Critical Appraisal Skills Programme (CASP) for the Cohort Studies, and Qualitative Studies. Besides, the Joanna Briggs Institute Meta-Analysis of Statistics Assessment and Review Instrument (JBI-MAStARI) for studies which employed other designs was used (7). We addressed PRISMA checklist requirements. Finally, after excluding 15 records with eligibility assessment scores below 0.33 points (<33%), the final review was done on 59 records. Throughout the processes, we attempted to maintain the original intentions of authors such as effects on patients, effects on healthcare delivery process, effects on quality care, and effects on efficiency in service delivery.

Figure 1.

Figure 1

Study selection flowchart

Ethics approval and consent: The research protocol was approved by the review committee of the Baqiyatallah University of Medical Sciences.

Results

Our search initially retrieved 158 studies. However, 132 papers were excluded by reviewing title and abstract and assessing full-text due to non-relevance. Then, 15 studies were excluded after final quality measurement and scoring for primary screening due to receiving below 0.33 points (<33%). Finally, 58 eligible peer-reviewed original articles were included in the final review (Figure 1 and Table 2).

Table 2.

Studies examining outcomes of emergency department (ED) crowding

Author
Year
Study Design Sample Quality Outcome variable
Cremonesi,2015 survey 54,254 patients High average per-patient cost; severity of health condition
Wang,2015 prospective pilot 3139 patients High average length of stay (LOS); patient Left without being seen (LWBS)
Shenoi,2009 cross-sectional 63,780 admissions High diversion
Fee,2007 cross-sectional 39,000 visits High ED volume at the time of arrival
Ben-Yakov,2015 cohort 9,759 patients High ED crowding; patient disposition (admission/discharge)
Cha,2011 regression 125,031 patients High mean patient volume over 8-hour; hospital mortality
Chang,2017 longitudinal 2,619 hospitals High LOS for admitted patients
Chiu,2017 cohort 70,222 visits High ED occupancy status; decision-making time; LOS; patient disposition
Depinet,2014 cross-sectional 9,976 patients High time to critically abnormal vital sign reassessment; patients waiting for admission, patients waiting in the lobby
Derose,2014 cohort 136,740 patients High inpatient mortality; ED LOS
Dubin,2013 retrospective 69 patients High emergency physician (EP) errors; number of patients boarding at the time of patient disposition
Epstein,2012 cohort 533 patients High occurrence of preventable medical errors; ED Occupancy
Fee,2011 cross-sectional 486 patients High arrival-to-antibiotic-administration times; number of ED patients requiring admission at the time of arrival
Gabayan,2015 cohort 625,096 visits High inpatient admission; death within 7 days
Gaieski,2017 cohort 2913 patients High ED occupancy; waiting patients; time to antibiotics; mortality
Hong,2013 cross-sectional 1296 patients High delayed resuscitation efforts; hospital mortality
Hsia,2013 cross-sectional 3,368,527 patients High ED crowding; bounceback admission
Hwang,2008 cross-sectional 1,068 patient High number of admitted patients; pain care measures
Jo,2012 cross-sectional 477 cases High 28-day mortality; timeliness of antibiotic therapy
Jo,2014 cross-sectional 54,410 patients High Emergency department occupancy ratio; ED LOS
Jo,2015 cross-sectional 1801 patients High ED occupancy ratio; inpatient mortality
Kennebeck,2011 cohort 190 patients High ED crowding; timeliness of antibiotic administration
Kulstad,2009 cross-sectional 17 patients High time to the first electrocardiogram (ECG); time to patient arrival in catheterization laboratory; occupancy rate
Kulstad,2010 observational NA High average daily occupancy rate and the emergency department work index (EDWIN) score; number of medication errors
Lee,2012 prospective review 11491 adults High ED crowding
McCarthy,2009 cohort 4 EDs High crowding at 30-minute intervals throughout each patient's ED stay; waiting room time; treatment time; and boarding time; occupancy rate
McCusker,2014 cohort 677,475 patients High 30-day outcomes: mortality, return ED visits, occupancy ratio separately for ED bed and waiting room patients
Medley,2010 prospective review 6,640 imaging studies High number of radiology studies ordered per patient; occupancy rate
Michelson,2012 cohort 198,778 visits High ED occupancy rate; return visits to the ED within 48 hours
Mills,2009 cross-sectional 976 patients High administration of and delays in time to analgesia
Mills,2010 prospective cohort 767 patients High ED crowding; time from triage to computed tomography (CT) read
Muller,2015 cross-sectional 40 ED bed High time to initial physician assessment; and daily nursing hours
Mullins,2014 ecological 4810 hospitals High LWBS; waiting times; boarding times; and LOS for admitted and discharged patients
O'Connor,2014 pilot 500 patients High triage time; date; treatment area; time to physician initial assessment; return ED visits within 14 days
Pines,2007 cohort 694 patients High delay (>4 hours from arrival)
Pines,2007 cross-sectional 741 patients High ED crowding
Pines,2008 cohort 1,469 patients High ED crowding (hallway placement, waiting times, and boarding times); patient satisfaction
Pines,2008 cohort 13,758 patients High Poor care; a delay (>1 hour) from triage to first pain medication; a delay (>1 hour) from room placement to first pain medication
Pines,2009 cross-sectional 4574 patients High inpatient adverse outcomes
Pines,2010 retrospective cohort 1,716 patients High ED crowding; ED occupancy, waiting patients, admitted patients, and patient-hours); overall LOS; time to treatment
Reznek,2017 retrospective 463 patients High Door-to-Imaging Time (DIT) within the 25-minute goal
Shenoi,2011 cross-sectional 161 patients High ED census; time to analgesic administration
Shin,2013 retrospective 770 patients High ED occupancy rate; compliance
Sikka,2010 correlation 334 patients High overall time to antibiotic administration
Sills,2011 cross-sectional 927 patients High ED occupancy; number waiting to see an attending-level physician
Sun,2013 cohort 995,379 ED visits, 187 hospitals High inpatient mortality; hospital length of stay; costs
Tekwani,2013 cross-sectional 1591 surveys High ED crowding; hospital diversion status; satisfaction
van der Linden,2014 cohort 169 patients High walkout from emergency
Van Der Linden,2016 retrospective 39110 patient High time to triage; time to treatment; age; 24-h mortality; 10-day mortality.
van der Linden,2016 cross-sectional 49539 patient High occupancy ratio; ED occupancy; LOS; time to triage
Verelst,2015 cohort 108,229 patients High in-hospital death; hospital; acquired morbidities; total hospital stay
Wang,2017 cohort 1345 participants High ED crowding; patient real-time satisfaction.
Ward,2015 cross-sectional 405 hospitals High admitted LOS; discharged LOS; boarding time; waiting time
Wiler,2013 cross-sectional 87,705 visits High patient LWBS
Wu,2015 cohort 852 patients High inpatient outcomes
Phillips, 2017 cohort 2,557 patients High ED LOS
Higginson, 2017 cross-sectional NA High bed occupancy
Geelhoed,2012 quasi-experimental NA High mortality rates; overcrowding rates

The consequences of patient crowding in hospitals are multifaceted involving effects related to patient health outcomes, healthcare delivery system and the community at large. Table 3 presents a summary of the commonly reported outcomes of ED crowding. ED crowding leads to delayed care for emergency patients and risk of not being visited by clinical care providers in a timely manner (8-14). The patients may react to prolonged stay to get services and to the crowding by frequent walkouts (15). The worsening of their illness (16) could result in frequent re-admissions (17, 18), prolonged hospitalizations (16, 19, 20), and related costs (21). Dissatisfaction of emergency patients (22-25), medication errors and adverse events (26-29), and patient death (16, 17, 19-21, 30-36) were also common consequences.

Table 3.

Effects of crowding in emergency departments

Effects on patients
  • Delayed assessment or treatment; not being seen; not given care (8-14)

  • Increased walkouts due to perceived ED length of stay (LOS) (15)

  • Morbidity (16)

  • Frequent readmissions (17, 18)

  • Prolonged hospitalization (16, 19, 20)

  • The high cost of treatment (21)

  • Low satisfaction (22-25)

  • Medication errors and adverse events (26-29)

  • Mortality (16, 17, 19-21, 30-36)

Healthcare delivery system process
  • High workload (41)

  • Delayed service provision/decision making and increased ED LOS (20, 21, 31, 35, 36, 40-54)

  • Discharging patients with high-risk clinical features (17)

  • Diverting patients to other facilities to reduce load (37)

  • High patient re-admission rate (22)

  • Decreased admission of patients due to crowding (38)

  • Decreased discharge rate of patients despite crowding (17)

  • High patient admission rate to general wards and ICU (40)

  • Overutilization of diagnostic imaging and laboratory tests (40)

  • Prolonged time to receive and transfer outpatients (39)

Effects on quality care
  • Shorter time to investigate patients’ conditions (49)

  • Poor infection prevention and control measures (63)

  • Low compliance with standards of care (19)

  • Compromised quality of care (12, 22, 41, 51, 57, 64-66)

  • High bed occupancy rate

Effects on efficiency in service delivery
  • Poor performance, low efficiency, and high cost of care/treatment (8, 14, 16, 36, 55, 56, 58)

The response to emergency and non-emergency patients influences the quality of services provided, patients’ outcomes and the healthcare system. Discharge of patients even with high-risk clinical features (17) and diverting the patients to other facilities (37) might have affected the health outcomes. These conditions not only decrease admission rates (38) and prolong the time to receive and transfer outpatients (39), but also compromise the patients' health outcomes and lead to high admission and re-admission rates (22, 36, 40) followed by a decrease in discharge rate of patients (17). In addition, the prolonged hospitalization of patients leads to overutilization of diagnostic and other laboratory facilities (40).

The crowding of the EDs negatively influences both the healthcare delivery process and the outcomes. The high workload (41) results in delayed service provision, delayed clinical decision making, and increased length of stay (LOS) of patients (20, 21, 31, 35, 36, 40-54). These situations negatively influence the quality of services and efficiency (8, 14, 16, 36, 55-58). A properly managed medical emergency contributes to the prevention of the event in communities. For example, a successfully treated patient with community-acquired pneumonia will be less likely to transmit the disease to other community members (13).

Discussion

This systematic review synthesized the outcomes related to ED crowding in hospitals. Crowding of ED can result in consequences for emergency patients’ health outcomes, the healthcare delivery system, and the community at large.

The high inflow of emergency patients to ED leads to crowding of the ED, which can in turn negatively affect the healthcare delivery process and outcomes. Delayed emergency healthcare service provision and patients leaving without being seen (LWBS) (8-14) have been commonly identified as consequences of crowding. This condition could inevitably lead to increased walkout of patients due to the perceived high length of stay. As a result, the emergency patients' morbidity worsened, and subsequent mortalities increased (16, 17, 19-21, 30-36). The frequent readmissions and prolonged hospitalizations of emergency patients not only increase ED crowding, but also negatively affect the cost of treatment (21) and patient satisfaction (22-25). Hoot and Aronsky in their systematic review identified a direct relationship between ED crowding and emergency patient death, reduced quality of care, and increased treatment costs (59). Delayed patient assessment and care provision could result in increased mortality, medical error, and decreased patient satisfaction (60).

The increase in the workload of emergency healthcare staff due to the high patient flow results in delayed clinical decision making and emergency healthcare service provision and increased ED LOS of patients (20, 21, 31, 35, 36, 40-42, 44-54, 61, 62). This condition again leads to discharge of patients even with high-risk clinical features (17) and to the diversion of emergency patients to other health facilities (37). ED crowding can also be associated with decreased admission rates (38), delayed emergency healthcare provision, and delay in transfer of emergency patients to inpatient wards (39). In contrast, the high admission and re-admission rates of emergency patients (22, 36, 40) followed by a decreased patient discharge rates (17) and prolonged hospitalization can lead to overutilization of diagnostic imaging and laboratory tests (40). Thus, several emergency healthcare-related consequences seem to be overlooked in the Morley et al. synthesis as they mainly focused on inpatient LOS and ED LOS (60). Our review broadly highlighted the healthcare delivery system-related consequences of ED crowding under the categories of healthcare delivery process, quality care, and efficiency.

ED crowding can negatively affect the quality of emergency healthcare. The higher the number of emergency patients, the longer the time it takes to investigate their conditions and to take supportive actions (49). These conditions can lead to reduced emergency healthcare quality and poor healthcare outcomes, which may result in an increase in bed occupancy rate (63). Besides, these conditions may negatively affect performances and result in inefficiency due to an increase in treatment costs (8, 14, 16, 36, 55, 56, 58). Similarly, others also identified the negative influence of ED crowding on the cost of treatment (59) and non-adherence to best practice guidelines for emergency service provision (60).

Strengths and Limitation

This systematic review synthesized original articles related to outcomes of the emergency department crowding in hospitals globally. Several studies identified complex issues related to emergency department crowding. Our review identified several crowding-related challenges and consequences including patient and staff reactions. The relevant original articles on ED crowding were accessed from the PubMed, Embase, and google scholar databases using comprehensive search keywords. The qualities of the records have been assessed using relevant checklists and those with low quality have been excluded. Our review also adds to the comprehensiveness of the view about the issues. The more explicit schematization of our synthesis compared to other existing reviews can facilitate a better understanding of the complex phenomenon. However, this review has certain limitations. It used study reports published only in English retrieved from the two mentioned sources. Moreover, the reviewed studies did not have a shared definition of crowding.

Conclusion:

ED crowding affects individual patients, healthcare systems and communities at large. The negative influences of crowding on healthcare service delivery result in delayed service delivery, poor quality care, and inefficiency; all negatively affecting the emergency patients' healthcare outcomes, in turn. This review highlights the importance of response to emergencies and emergency-related crowding and preventing the consequences to better address the healthcare needs of emergency patients and increase the effectiveness of healthcare service delivery centers.

List of abbreviations

ED: Emergency Department

MeSH: Medical Subject Headings

CASP: Critical Appraisal Skills Programme

JBI-MAStARI: Joanna Briggs Institute Meta-Analysis of Statistics Assessment and Review Instrument

LWBS: Left Without Being Seen

LOS: Length of Stay

Availability of data and supporting materials:

The datasets used and analyzed during the current study are available from the corresponding author on request.

Conflicts of interests:

No conflicts of interest

Funding:

Not applicable

Authors' contributions:

All the authors have contributed to development of the concept and production of the final manuscript.

Acknowledgments:

Not applicable

References

  • 1.Higginson I. Emergency department crowding. Emerg Med J. 2012;29(6):437–43. doi: 10.1136/emermed-2011-200532. [DOI] [PubMed] [Google Scholar]
  • 2.Derlet RW, Richards JR. Ten solutions for emergency department crowding. Western Journal of Emergency Medicine. 2008;9(1) [PMC free article] [PubMed] [Google Scholar]
  • 3.Makama JG, Iribhogbe P, Ameh EA. Overcrowding of accident & emergency units: is it a growing concern in Nigeria? African health sciences. 2015;15(2):457–65. doi: 10.4314/ahs.v15i2.20. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 4.Rathlev NK, Chessare J, Olshaker J, Obendorfer D, Mehta SD, Rothenhaus T, et al. Time series analysis of variables associated with daily mean emergency department length of stay. Annals of emergency medicine. 2007;49(3):265–71. doi: 10.1016/j.annemergmed.2006.11.007. [DOI] [PubMed] [Google Scholar]
  • 5.Yarmohammadian MH, Rezaei F, Haghshenas A, Tavakoli N. Overcrowding in emergency departments: a review of strategies to decrease future challenges. Journal of research in medical sciences: the official journal of Isfahan University of Medical Sciences. 2017:22. doi: 10.4103/1735-1995.200277. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 6.Iraqi IJ, Mahmoudi H. Causes and Consequences of Emergency Department Overcrowding; Methods for Resolving it. Health Research. 2016;1(4):239–44. [Google Scholar]
  • 7.Erren M, Reinecke H, Junker R, Fobker M, Schulte H, Schurek JO, et al. Systemic inflammatory parameters in patients with atherosclerosis of the coronary and peripheral arteries. Arteriosclerosis, thrombosis, and vascular biology. 1999;19(10):2355–63. doi: 10.1161/01.atv.19.10.2355. [DOI] [PubMed] [Google Scholar]
  • 8.Depinet HE, Iyer SB, Hornung R, Timm NL, Byczkowski TL. The effect of emergency department crowding on reassessment of children with critically abnormal vital signs. Academic Emergency Medicine. 2014;21(10):1116–20. doi: 10.1111/acem.12478. [DOI] [PubMed] [Google Scholar]
  • 9.Gaieski DF, Agarwal AK, Mikkelsen ME, Drumheller B, Sante SC, Shofer FS, et al. The impact of ED crowding on early interventions and mortality in patients with severe sepsis. The American journal of emergency medicine. 2017;35(7):953–60. doi: 10.1016/j.ajem.2017.01.061. [DOI] [PubMed] [Google Scholar]
  • 10.Wang H, Robinson RD, Cowden CD, Gorman VA, Cook CD, Gicheru EK, et al. Use of the SONET score to evaluate Urgent Care Center overcrowding: a prospective pilot study. BMJ open. 2015;5(4):e006860. doi: 10.1136/bmjopen-2014-006860. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 11.Wiler JL, Bolandifar E, Griffey RT, Poirier RF, Olsen T. An emergency department patient flow model based on queueing theory principles. Academic Emergency Medicine. 2013;20(9):939–46. doi: 10.1111/acem.12215. [DOI] [PubMed] [Google Scholar]
  • 12.Pines JM, Hollander JE. Emergency department crowding is associated with poor care for patients with severe pain. Annals of emergency medicine. 2008;51(1):1–5. doi: 10.1016/j.annemergmed.2007.07.008. [DOI] [PubMed] [Google Scholar]
  • 13.Fee C, Weber EJ, Maak CA, Bacchetti P. Effect of emergency department crowding on time to antibiotics in patients admitted with community-acquired pneumonia. Annals of emergency medicine. 2007;50(5):501–9. doi: 10.1016/j.annemergmed.2007.08.003. [DOI] [PubMed] [Google Scholar]
  • 14.Reznek MA, Murray E, Youngren MN, Durham NT, Michael SS. Door-to-imaging time for acute stroke patients is adversely affected by emergency department crowding. Stroke. 2017;48(1):49–54. doi: 10.1161/STROKEAHA.116.015131. [DOI] [PubMed] [Google Scholar]
  • 15.van der Linden MC, Lindeboom R, van der Linden N, van den Brand CL, Lam RC, Lucas C, et al. Walkouts from the emergency department: characteristics, reasons and medical care needs. European Journal of Emergency Medicine. 2014;21(5):354–9. doi: 10.1097/MEJ.0000000000000086. [DOI] [PubMed] [Google Scholar]
  • 16.Verelst S, Wouters P, Gillet J-B, Van den Berghe G. Emergency department crowding in relation to in-hospital adverse medical events: a large prospective observational cohort study. The Journal of emergency medicine. 2015;49(6):949–61. doi: 10.1016/j.jemermed.2015.05.034. [DOI] [PubMed] [Google Scholar]
  • 17.Ben‐Yakov M, Kapral MK, Fang J, Li S, Vermeulen MJ, Schull MJ. The association between emergency department crowding and the disposition of patients with transient ischemic attack or minor stroke. Academic Emergency Medicine. 2015;22(10):1145–54. doi: 10.1111/acem.12766. [DOI] [PubMed] [Google Scholar]
  • 18.Hsia RY, Asch SM, Weiss RE, Zingmond D, Gabayan G, Liang L-J, et al. Is emergency department crowding associated with increased “bounceback” admissions? Medical care. 2013;51:11. doi: 10.1097/MLR.0b013e3182a98310. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 19.Shin TG, Jo IJ, Choi DJ, Kang MJ, Jeon K, Suh GY, et al. The adverse effect of emergency department crowding on compliance with the resuscitation bundle in the management of severe sepsis and septic shock. Critical Care. 2013;17(5):R224. doi: 10.1186/cc13047. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 20.Cha WC, Do Shin S, Cho JS, Song KJ, Singer AJ, Kwak YH. The association between crowding and mortality in admitted pediatric patients from mixed adult-pediatric emergency departments in Korea. Pediatric emergency care. 2011;27(12):1136–41. doi: 10.1097/PEC.0b013e31823ab90b. [DOI] [PubMed] [Google Scholar]
  • 21.Sun BC, Hsia RY, Weiss RE, Zingmond D, Liang L-J, Han W, et al. Effect of emergency department crowding on outcomes of admitted patients. Annals of emergency medicine. 2013;61(6):605–11. doi: 10.1016/j.annemergmed.2012.10.026. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 22.Mullins PM, Pines JM. National ED crowding and hospital quality: results from the 2013 Hospital Compare data. The American journal of emergency medicine. 2014;32(6):634–9. doi: 10.1016/j.ajem.2014.02.008. [DOI] [PubMed] [Google Scholar]
  • 23.Pines JM, Iyer S, Disbot M, Hollander JE, Shofer FS, Datner EM. The effect of emergency department crowding on patient satisfaction for admitted patients. Academic Emergency Medicine. 2008;15(9):825–31. doi: 10.1111/j.1553-2712.2008.00200.x. [DOI] [PubMed] [Google Scholar]
  • 24.Tekwani KL, Kerem Y, Mistry CD, Sayger BM, Kulstad EB. Emergency department crowding is associated with reduced satisfaction scores in patients discharged from the emergency department. Western Journal of Emergency Medicine. 2013;14(1) doi: 10.5811/westjem.2011.11.11456. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 25.Wang H, Ojha RP, Robinson RD, Jackson BE, Shaikh SA, Cowden CD, et al. Optimal measurement interval for emergency department crowding estimation tools. Annals of emergency medicine. 2017;70(5):632–9. doi: 10.1016/j.annemergmed.2017.04.012. [DOI] [PubMed] [Google Scholar]
  • 26.Dubin J, Blumenthal J, Milzman D. 127 Emergency Department Crowding and Physician Inexperience are Synergistically Associated With Increased Physician Errors. Annals of Emergency Medicine. 2013;62:4. [Google Scholar]
  • 27.Epstein SK, Huckins DS, Liu SW, Pallin DJ, Sullivan AF, Lipton RI, et al. Emergency department crowding and risk of preventable medical errors. Internal and emergency medicine. 2012;7(2):173–80. doi: 10.1007/s11739-011-0702-8. [DOI] [PubMed] [Google Scholar]
  • 28.Kulstad EB, Sikka R, Sweis RT, Kelley KM, Rzechula KH. ED overcrowding is associated with an increased frequency of medication errors. The American journal of emergency medicine. 2010;28(3):304–9. doi: 10.1016/j.ajem.2008.12.014. [DOI] [PubMed] [Google Scholar]
  • 29.Pines JM, Pollack Jr CV, Diercks DB, Chang AM, Shofer FS, Hollander JE. The association between emergency department crowding and adverse cardiovascular outcomes in patients with chest pain. Academic Emergency Medicine. 2009;16(7):617–25. doi: 10.1111/j.1553-2712.2009.00456.x. [DOI] [PubMed] [Google Scholar]
  • 30.Derose SF, Gabayan GZ, Chiu VY, Yiu SC, Sun BC. Emergency department crowding predicts admission length-of-stay but not mortality in a large health system. Medical care. 2014;52(7):602. doi: 10.1097/MLR.0000000000000141. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 31.Hong KJ, Do Shin S, Song KJ, Cha WC, Cho JS. Association between ED crowding and delay in resuscitation effort. The American journal of emergency medicine. 2013;31(3):509–15. doi: 10.1016/j.ajem.2012.09.029. [DOI] [PubMed] [Google Scholar]
  • 32.Jo S, Jeong T, Jin YH, Lee JB, Yoon J, Park B. ED crowding is associated with inpatient mortality among critically ill patients admitted via the ED: post hoc analysis from a retrospective study. The American journal of emergency medicine. 2015;33(12):1725–31. doi: 10.1016/j.ajem.2015.08.004. [DOI] [PubMed] [Google Scholar]
  • 33.Jo S, Jin YH, Lee JB, Jeong T, Yoon J, Park B. Emergency department occupancy ratio is associated with increased early mortality. The Journal of emergency medicine. 2014;46(2):241–9. doi: 10.1016/j.jemermed.2013.05.026. [DOI] [PubMed] [Google Scholar]
  • 34.McCusker J, Vadeboncoeur A, Lévesque JF, Ciampi A, Belzile E. Increases in emergency department occupancy are associated with adverse 30‐day outcomes. Academic Emergency Medicine. 2014;21(10):1092–100. doi: 10.1111/acem.12480. [DOI] [PubMed] [Google Scholar]
  • 35.Van Der Linden N, Van Der Linden MC, Richards JR, Derlet RW, Grootendorst DC, Van Den Brand CL. Effects of emergency department crowding on the delivery of timely care in an inner-city hospital in the Netherlands. European Journal of Emergency Medicine. 2016;23(5):337–43. doi: 10.1097/MEJ.0000000000000268. [DOI] [PubMed] [Google Scholar]
  • 36.Wu D, Zhou X, Ye L, Gan J, Zhang M. Emergency department crowding and the performance of damage control resuscitation in major trauma patients with hemorrhagic shock. Academic Emergency Medicine. 2015;22(8):915–21. doi: 10.1111/acem.12726. [DOI] [PubMed] [Google Scholar]
  • 37.Shenoi RP, Ma L, Jones J, Frost M, Seo M, Begley CE. Ambulance diversion as a proxy for emergency department crowding: the effect on pediatric mortality in a metropolitan area. Academic emergency medicine. 2009;16(2):116–23. doi: 10.1111/j.1553-2712.2008.00317.x. [DOI] [PubMed] [Google Scholar]
  • 38.Michelson KA, Monuteaux MC, Stack AM, Bachur RG. Pediatric emergency department crowding is associated with a lower likelihood of hospital admission. Academic Emergency Medicine. 2012;19(7):816–20. doi: 10.1111/j.1553-2712.2012.01390.x. [DOI] [PubMed] [Google Scholar]
  • 39.Ward MJ, Baker O, Schuur JD. Association of emergency department length of stay and crowding for patients with ST-elevation myocardial infarction. Western Journal of Emergency Medicine. 2015;16(7):1067. doi: 10.5811/westjem.2015.8.27908. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 40.Chiu I-M, Lin Y-R, Syue Y-J, Kung C-T, Wu K-H, Li C-J. The influence of crowding on clinical practice in the emergency department. The American journal of emergency medicine. 2018;36(1):56–60. doi: 10.1016/j.ajem.2017.07.011. [DOI] [PubMed] [Google Scholar]
  • 41.Fee C, Weber EJ, Bacchetti P, Maak CA. Effect of emergency department crowding on pneumonia admission care components. The American journal of managed care. 2011;17(4):269–78. [PubMed] [Google Scholar]
  • 42.Gabayan GZ, Derose SF, Chiu VY, Yiu SC, Sarkisian CA, Jones JP, et al. Emergency department crowding and outcomes after emergency department discharge. Annals of emergency medicine. 2015;66(5):483–92. doi: 10.1016/j.annemergmed.2015.04.009. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 43.Huang EP-C, Liu SS-H, Fang C-C, Chou H-C, Wang C-H, Yen Z-S, et al. The impact of adding clinical assistants on patient waiting time in a crowded emergency department. Emerg Med J. 2013;30(12):1017–9. doi: 10.1136/emermed-2012-201611. [DOI] [PubMed] [Google Scholar]
  • 44.Kennebeck SS, Timm NL, Kurowski EM, Byczkowski TL, Reeves SD. The association of emergency department crowding and time to antibiotics in febrile neonates. Academic Emergency Medicine. 2011;18(12):1380–5. doi: 10.1111/j.1553-2712.2011.01221.x. [DOI] [PubMed] [Google Scholar]
  • 45.Kulstad EB, Kelley KM. Overcrowding is associated with delays in percutaneous coronary intervention for acute myocardial infarction. International journal of emergency medicine. 2009;2(3):149. doi: 10.1007/s12245-009-0107-x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 46.McCarthy ML, Zeger SL, Ding R, Levin SR, Desmond JS, Lee J, et al. Crowding delays treatment and lengthens emergency department length of stay, even among high-acuity patients. Annals of emergency medicine. 2009;54(4):492–503. doi: 10.1016/j.annemergmed.2009.03.006. [DOI] [PubMed] [Google Scholar]
  • 47.Mills AM, Baumann BM, Chen EH, Zhang K-Y, Glaspey LJ, Hollander JE, et al. The impact of crowding on time until abdominal CT interpretation in emergency department patients with acute abdominal pain. Postgraduate medicine. 2010;122(1):75–81. doi: 10.3810/pgm.2010.01.2101. [DOI] [PubMed] [Google Scholar]
  • 48.Mills AM, Shofer FS, Chen EH, Hollander JE, Pines JM. The association between emergency department crowding and analgesia administration in acute abdominal pain patients. Academic Emergency Medicine. 2009;16(7):603–8. doi: 10.1111/j.1553-2712.2009.00441.x. [DOI] [PubMed] [Google Scholar]
  • 49.O’Connor E, Gatien M, Weir C, Calder L. Evaluating the effect of emergency department crowding on triage destination. International journal of emergency medicine. 2014;7(1):16. doi: 10.1186/1865-1380-7-16. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 50.Phillips JL, Jackson BE, Fagan EL, Arze SE, Major B, Zenarosa NR, et al. Overcrowding and its association with patient outcomes in a median-low volume emergency department. Journal of clinical medicine research. 2017;9(11) doi: 10.14740/jocmr3165w. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 51.Pines JM, Localio AR, Hollander JE, Baxt WG, Lee H, Phillips C, et al. The impact of emergency department crowding measures on time to antibiotics for patients with community-acquired pneumonia. Annals of emergency medicine. 2007;50(5):510–6. doi: 10.1016/j.annemergmed.2007.07.021. [DOI] [PubMed] [Google Scholar]
  • 52.Pines JM, Prabhu A, Hilton JA, Hollander JE, Datner EM. The effect of emergency department crowding on length of stay and medication treatment times in discharged patients with acute asthma. Academic Emergency Medicine. 2010;17(8):834–9. doi: 10.1111/j.1553-2712.2010.00780.x. [DOI] [PubMed] [Google Scholar]
  • 53.Sikka R, Mehta S, Kaucky C, Kulstad EB. ED crowding is associated with an increased time to pneumonia treatment. The American journal of emergency medicine. 2010;28(7):809–12. doi: 10.1016/j.ajem.2009.06.023. [DOI] [PubMed] [Google Scholar]
  • 54.van der Linden MC, Meester BE, van der Linden N. Emergency department crowding affects triage processes. International emergency nursing. 2016;29:27–31. doi: 10.1016/j.ienj.2016.02.003. [DOI] [PubMed] [Google Scholar]
  • 55.Shenoi R, Ma L, Syblik D, Yusuf S. Emergency department crowding and analgesic delay in pediatric sickle cell pain crises. Pediatric emergency care. 2011;27(10):911–7. doi: 10.1097/PEC.0b013e3182302871. [DOI] [PubMed] [Google Scholar]
  • 56.Cremonesi P, di Bella E, Montefiori M, Persico L. The robustness and effectiveness of the triage system at times of overcrowding and the extra costs due to inappropriate use of emergency departments. Applied health economics and health policy. 2015;13(5):507–14. doi: 10.1007/s40258-015-0166-5. [DOI] [PubMed] [Google Scholar]
  • 57.Chang AM, Lin A, Fu R, McConnell KJ, Sun B. Associations of Emergency Department Length of Stay With Publicly Reported Quality‐of‐care Measures. Academic Emergency Medicine. 2017;24(2):246–50. doi: 10.1111/acem.13102. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 58.Medley D, Morris J, Stone C, PCC CC, FFP FFP. CROWDING AND PHYSICIAN PRACTICE: AN ASSOCIATION BETWEEN EMERGENCY DEPARTMENT CROWDING AND RATES OF IMAGING STUDIES ORDERED BY PHYSICIANS [Google Scholar]
  • 59.Hoot NR, Aronsky D. Systematic review of emergency department crowding: causes, effects, and solutions. Annals of emergency medicine. 2008;52(2):126–36. doi: 10.1016/j.annemergmed.2008.03.014. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 60.Morley C, Unwin M, Peterson GM, Stankovich J, Kinsman L. Emergency department crowding: A systematic review of causes, consequences and solutions. PloS one. 2018;13(8):e0203316. doi: 10.1371/journal.pone.0203316. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 61.Graham J, Aitken ME, Shirm S. Correlation of measures of patient acuity with measures of crowding in a pediatric emergency department. Pediatric emergency care. 2011;27(8):706–9. doi: 10.1097/PEC.0b013e318226c7dd. [DOI] [PubMed] [Google Scholar]
  • 62.Hwang U, Richardson L, Livote E, Harris B, Spencer N, Sean Morrison R. Emergency department crowding and decreased quality of pain care. Academic Emergency Medicine. 2008;15(12):1248–55. doi: 10.1111/j.1553-2712.2008.00267.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  • 63.Muller MP, Carter E, Siddiqui N, Larson E. Hand hygiene compliance in an emergency department: the effect of crowding. Academic Emergency Medicine. 2015;22(10):1218–21. doi: 10.1111/acem.12754. [DOI] [PubMed] [Google Scholar]
  • 64.Lee C-C, Lee N-Y, Chuang M-C, Chen P-L, Chang C-M, Ko W-C. The impact of overcrowding on the bacterial contamination of blood cultures in the ED. The American journal of emergency medicine. 2012;30(6):839–45. doi: 10.1016/j.ajem.2011.05.026. [DOI] [PubMed] [Google Scholar]
  • 65.Sills MR, Fairclough D, Ranade D, Kahn MG. Emergency department crowding is associated with decreased quality of care for children with acute asthma. Annals of emergency medicine. 2011;57(3):191–200. doi: 10.1016/j.annemergmed.2010.08.027. [DOI] [PubMed] [Google Scholar]
  • 66.Higginson I, Kehoe A, Whyatt J, Smith JE. The 4-hour standard is a meaningful quality indicator: correlation of performance with emergency department crowding. European Journal of Emergency Medicine. 2017;24(1):25–8. doi: 10.1097/MEJ.0000000000000417. [DOI] [PubMed] [Google Scholar]

Articles from Archives of Academic Emergency Medicine are provided here courtesy of Shahid Beheshti University of Medical Sciences

RESOURCES