Crowding in the Emergency Department: Strategies to End It
- Dec 8th, 2015
- Justin Bright
Author: Abdullah Bakhsh, MBBS (EM Resident Physician, Emory Emergency Medicine) // Editor: Justin Bright, MD (@JBright2021)
The ACEP Crowding Resources Task Force adopted the following definition of ED crowding: “A situation in which the identified need for emergency services outstrips available resources in the ED. This situation occurs in hospital EDs when there are more patients than staffed ED treatment beds and wait times exceed a reasonable period . Crowding involves an inability to appropriately triage patients, with large numbers of patients accumulating in the ED waiting area of any triage assessment category.” This crowding causes patients to be evaluated and monitored in less than ideal settings – such as in the ED waiting room or hallways – as they await an ED treatment bed.
A 62 year-old male presents to the emergency department (ED) with low back pain after a mechanical fall as he slipped on a puddle of water. After a 14 hour wait, he finally gets moved to an exam room. Upon examination you notice lumbar spine tenderness with inability to flex his left thigh. A CT of his lumbar spine demonstrates a L2 vertebral body fracture with retropulsion. The patient has to be transferred to another hospital due to unavailability of neurosurgical services. Delays in care were mostly due to boarding patients and lack of staff.
Dangers of ED Crowding:
Emergency department crowding threatens quality and access to health care . Delays to analgesia, antibiotic therapy, thrombolysis, or percutaneous coronary intervention as a result of ED crowding are all well described [2-5]. Intensive Care Unit (ICU) patients boarding in the ED subjected to a delay of more than 6 hours in transfer to an ICU had increased hospital length of stay (7 versus 6 days), and higher mortality rates (10.7% versus 8.4%) . Crowding also impairs dignity, privacy, and completeness of care. Errors are increased with ED crowding. Many of these are errors of omission rather than errors of commission since the emergency staff must simultaneously care for inpatients and focus on the new emergencies coming in the door [7,8].
What Causes ED Crowding:
The number of patients in the emergency department at any given time is a function of three variables: input, throughput, and output. This can be explained by Asplin’s model of acute care (figure 1). Before interventions are instituted, it is critical to identify what the main causes of crowding are in an individual emergency department. Researchers initially focused on input factors such as use of the ED for non-emergent complaints. Their data ultimately showed that their reasons for doing so included insufficient or untimely access to primary care [23,24]. More recent research, however, strongly suggests that these input factors are not the root cause of the problem [25,26,27,28]. Inadequate staffing is a commonly studied throughput factor that may cause crowding. Lower staffing levels of physicians and triage nurses predisposed patients to wait longer for care . The use of ancillary services, including computed tomographic (CT) scanning and other procedures, prolonged the ED length of stay among surgical critical care patients . The most common cause of ED crowding is thought to be access block (output). Patients experiencing access block, defined by boarding time exceeding 8 hours, was associated with increased diversion, waiting times, and occupancy level in an Australian ED . Length of stay in one ED increased substantially when the hospital occupancy levels exceeded 90% .
EMERGENCY DEPARTMENT INTERVENTIONS
As crowding increased, the inflow of patients exceeded outflow for extended hours each day, resulting in the need to place patients somewhere . For a growing number of EDs the solution was to move both stable and semi-stable patients from licensed ED beds into adjacent ED hallways, thus freeing up the official ED bed for another patient . If the chief reason for overcrowding is “exit block,” then simply building a larger ED to increase capacitance may not solve the problem [11,12]. Emergency and inpatient physicians at the Stony Brook University Hospital in New York collaborated and developed a program whereby admitted hallway patients are transferred out of the ED to inpatient hallways . Patients receive more attention in a quieter and more private environment. This transfer of patient care has been shown to be safe, and patients prefer being boarded in inpatient hallways [14-16]. In some academic centers “door to floor” time exceeds 21 hours for 90% of admitted patients. It would make sense then to move admitted patients from ED hallways up to the hallways of the inpatient areas when the hospital is full. Such a proposal is not novel and, in fact, is used extensively on the East Coast .
INCREASING EMERGENCY DEPARTMENT PERSONNEL
One study concluded that the addition of a physician during a busy shift decreased the length of stay from 176 minutes to 141 minutes for patients discharged after evaluation in the emergency department . One hospital activated reserve personnel as needed during the viral epidemic season, reducing the waiting time by 15 minutes and the rate of patients leaving without being seen by 37%.. For each additional triage nurse per ED patient, waiting times for all other patients were reduced by an average of 28.8 minutes and for each additional physician per ED patient waiting, waiting times were reduced by 82 minutes .
TRIAGE BASED CARE PROTOCOL AND NURSE INITIATED WORKUPS
In the literature, advanced triage protocols have been reported to decrease patient length of stay,[38,39] decrease the time to pain treatment,[40,41] increase patient comfort,[40,42] decrease time to antibiotics in patients admitted with pneumonia, decrease delays in performing ECGs and administering thrombolytic agents for myocardial infarction, and decrease costs associated with patients requiring one-to-one monitoring. It has also been shown to improve throughput and employee satisfaction, and decrease medical errors. Training nursing staff to order X-rays at triage is helpful and cuts the patient’s stay by around 20 minutes . In another study, triage nurse initiated radiography using OAR leads to a statistically significant decrease of 20 minutes in the median ED LOS at a tertiary care center .
IMPLEMENTING ED FAST TRACK
Establishment of an effective fast track service line decreased patient wait times,[47-51] increased throughput of lower-acuity patients,[47-49,52-54] and reduced LWBS rates[47-49]. It also decreased hospital admissions, decreased testing and costs, and increased available provider time for higher- acuity patients . Overall ED length of stay was shortened,[47-49, 51-52, 54] patient satisfaction was improved, [55,56] and did not negatively affect clinical outcomes (unscheduled ED return visits or mortality rate) [49,53,56]. The success of fast-track systems is dependent on the availability of dedicated medical and nursing staff while adhering to rigid protocols of what patients can appropriately be placed in that treatment area [58,59]. Failure to staff fast-track areas with appropriate medical staff results in interruptions to fast-track programs . This usually arises when fast-track staff offers their attention to patients in other more acute ED treatment areas .
A compilation of fast-track guidelines can be found here:
Traditionally, patients who require care beyond the first hours in the emergency department (ED) have been admitted to the hospital. Economic pressures for efficiency in health care have led to the need for new strategies for those with difficult to rapidly diagnose ED presentations. Thus, observation units are increasingly becoming an important component of the modern ED. The average ED length of stay for an admitted ED patient is 5.5 hours while the average length of stay of an inpatient is 5 days . Hospitals are increasingly being scrutinized for inpatients whose length of stay is one day or less . This length of stay defines a subset of patients whose clinical needs exceed what can realistically be achieved within the 6 hours of an ED visit, but if managed actively will require less than 24 hours of hospitalization. These “6-24 hour” patients are often eligible for a dedicated observation unit. An ED-managed observation care unit decreased ambulance diversion by 40% and halved the rate of patients leaving without being seen . Specific conditions appropriate for observation are:
Studies have indicated that roughly 4% of patients with acute coronary syndromes are inadvertently discharged from the ED, often due to diagnostic uncertainty. Four prospective randomized studies have shown that relative to inpatient admission, chest pain protocols are associated with lower cost, shorter length of stays, and improved resource utilization[63-66].
In a study by McDermott acute asthmatics were randomized to either aggressive emergency department observation unit (EDOU) care for an additional 9 hours or to routine inpatient care following standard ED treatment. They found that 59% of EDOU asthmatics were discharged home compared with control groups where all were admitted. There were no differences in the two groups during the follow-up period in terms of relapse rates or subsequent morbidities. However there were significant differences in their length of stays (8.8 hr vs 59 hr), costs ($1202 vs $2247), and quality of life .
Diercks reported that heart failure patients with a systolic blood pressure under 160 mm Hg on ED presentation and a normal initial cardiac Troponin I were significantly more likely to be discharged from the EDOU and not experience a 30-day adverse events (death, readmission, myocardial infarction, arrhythmias) .
In a small retrospective observational study the diagnosis of dehydration was identified as the highest risk for early return visit to the ED and subsequent admission to the hospital on early return . Hence, these patients are ideal for further management in the EDOU after initial resuscitation in the ED.
Transient Ischemic Attack
Ross reported a prospective study of 149 patients with transient ischemic attack who were randomized to either inpatient admission (control group) or ED observation unit admission for management using an accelerated diagnostic protocol . All patients with transient ischemic attack had normal findings on computed tomography (CT) of the head, electrocardiography, laboratory studies and no known embolic source. Both groups had orders for serial clinical examinations, a neurology consultation, carotid duplex ultrasonography, echocardiography, and cardiac monitoring. Accelerated diagnostic protocol patients with positive testing results were admitted. Compared with the inpatient control group, patients in the accelerated diagnostic protocol group had total lengths of stay that were half as long (26 versus 61 hours), lower 90-day total direct costs ($890 versus $1,547), and comparable 90-day clinical outcomes. Accelerated diagnostic protocol patients were more likely to undergo carotid imaging (97% versus 90%) and echocardiography (97% versus 73%). Both groups had comparable rates of related return visits, subsequent strokes, and major clinical events.
During the past 20 years, hospital admissions for atrial fibrillation have increased by 66% . A subset of patients, those with uncomplicated acute onset (<48 hours) atrial fibrillation, may be eligible for treatment in an EDOU based on prospective studies as well as current American Heart Association practice guideline.
Deep Venous Thrombosis
Recommendations for treatment of DVT by ACP and ACCP state that outpatient treatment should be provided whenever possible [72,73]. This approach has been found to be cost effective, reducing both healthcare costs and hospital length of stay [74-76]. Compared with inpatients, those treated for DVT at home have greater levels of physical activity and social functioning, and demonstrate a more rapid return to pre-morbid levels of activity [77-79]. Integrating the many necessary steps that contribute to successful outpatient DVT management often requires the coordination of multiple therapies and services.
Shen performed a prospective randomized control study of intermediate risk syncope patients who were randomized to a designated syncope unit or an inpatient admission following initial ED management which included an ECG and cardiac monitoring . The syncope unit protocol included serial vital signs, continuous cardiac monitoring for up to 6 hours. The results of this study showed that at the time of dismissal from the ED, the presumptive cause of syncope was established for 67% of patients in the syncope unit group compared to 10% in the standard care group. The total hospital bed days were reduced by 54% for patients in the syncope unit group and 2-year clinical outcomes, including all-cause mortality and recurrent syncope, were similar between EDOU and admitted control groups .
IMAGING IN THE ED
The use of IV-contrast only for the evaluation of patients presenting to the ED with abdominal pain has been shown to have a high sensitivity and specificity for the diagnosis of common causes of acute abdominal pain, such as acute appendicitis, diverticulitis, and SBO [29,30]. The impact of limiting PO contrast in such patients not only decreased ED LOS, but also allowed for earlier consultation and definitive treatment for patients with identified pathology, with over 2 hours in time saved for patients requiring operative interventions. The time test ordered to time test completed was a median of 72 minutes shorter for patients undergoing the IV-contrast only protocol. It would be expected that the decrease in ED LOS would approximate the time saved by not using oral contrast . The immediate use of whole body CT scans in trauma patients reduces median time in the ED by 8-35 minutes and time to the operating room but does not reduce mortality compared with selective imaging .
CARING FOR HALLWAY PATIENTS
For a growing number of EDs the solution had been to move both stable and semi-stable patients from licensed ED beds into adjacent ED hallways, thus freeing up the official ED bed for another patient . In these circumstances ED physicians face a difficult challenge. They must provide care to patients in the hallway with suboptimal nursing support and lack of privacy, which precludes a full history and physical examination. Patients may not be able to be appropriately monitored. Returning newly triaged patients back to the waiting room until a licensed ED bed becomes available poses a similar risk, as there is no way to directly observe or monitor patients. The type of patient that is placed on a gurney in the ED hallway varies by institution and may vary within the same institution depending on who is in charge during times of crowding. Groups placed in hallways include (1) patients awaiting care but considered too unstable or ill to remain in the waiting room, (2) patients undergoing active medical and trauma care, but no vacant ED bed is available, (3) patients who are being “boarded” while awaiting transfer to an inpatient bed or transfer to another institution, (4) patients who arrive by ambulance but do not require immediate emergency care, and (5) patients awaiting transfer to a psychiatric facility .
The concept originated in 2001 in the overcrowded emergency department at Stony Brook University Medical Center in Long Island, where patients piled up in the ED due to no available beds upstairs. This led to boarding patients, which in turn made the ED even more crowded and less efficient. Dr. Peter Vicellio, a practicing emergency physician and the clinical director of the emergency department at Stony Brook on Long Island, recognized that placing certain patients in inpatient hallways, would make beds available more quickly. Grant Innes and his group did a fantastic study on the overcapacity protocol, a true “before and after” study, at his institution . “The protocol reduced the length of stay for admitted patients in the emergency department by about 5 hours, and with more than 8,000 admissions annually, this frees up about 41,000 hours of ED stretcher time,” said Dr. Grant Innes, chairman of the emergency department at St. Paul’s Hospital.  Mean ED length of stay for all admitted patients fell from 19 to 14 hours, a statistically significant decline. ED length of stay fell by 9 hours, 1.6 hours, and 9.2 hours for admitted medical, surgical, and mental health patients, respectively, changes that also were statistically significant. And hospital length of stay dropped by about 1 day for typical medical, surgical, and mental health patients, Dr. Innes said . After OCP, arriving patients who were rated 1-3 (emergent-urgent) on the Canadian Triage and Acuity Scale rarely were left in ED waiting areas, and ambulance off-load delays dropped by 26%, he said.
The overcapacity protocol at Stony Brook can be found at: http://www.hospitalovercrowding.com/fullcapacity.htm
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