Chapter 123. Co-Management of Patients in the Emergency Department

1. What strategies may improve emergency department (ED) throughput and minimize ED crowding?

2. How can hospitalists and Emergency Medicine (EM) physicians collaborate to improve the care of patients boarded in the ED?

3. How can hospitalists and EM physicians improve the quality and safety of hand-offs between their departments?

4. What basic principles underlie the operation of an observation unit?

Co-management of patients in the emergency department (ED) by Emergency Physicians and Hospital Medicine physicians has become necessary to alleviate ED crowding and optimize care of patients boarded in the ED while awaiting an inpatient bed. This chapter describes the challenge of ED crowding and how co-management strategies can improve patient flow from the ED into the hospital and improve the safety of patients who must be boarded. The chapter also examines two additional strategies for decreasing ED crowding: establishing a process for the triage of patients to appropriate services and locations within the hospital, and using ED based observation units.

Emergency Department Crowding

The Institute of Medicine in its 2006 report entitled Hospital-Based Emergency Care: At the Breaking Point1 concluded that EDs in the United States are in crisis, with hospital crowding being the single largest contributor to long wait times and adverse clinical outcomes. Investigators have found an association between ED crowding and a higher risk of adverse cardiovascular outcomes in patients with an initial diagnosis of chest pain. Others have found that, for patients with non-ST segment elevation myocardial infarction, long ED stays are associated with decreased adherence to clinical guidelines and an increased incidence of repeat myocardial infarction. An estimated 91% of the nation's EDs are overcrowded at any given time.

The causes of ED crowding are myriad and include increased utilization, demographic changes (most significantly the aging of the population), shortages of particular types of health care providers, and changing financial trends. Most significant amongst these were increased utilization and insufficient numbers of inpatient hospital beds. From 1996 to 2006 ED visits increased 32%, from 90.3 million to 119.2 million, equating to 325,000 visits per day. During that same time the number of ED visits per 100 persons rose 18%, from 34.2 to 40.5. In 2005 approximately one-fifth of the U.S. population had visited an ED within the previous 12 months. Ironically, the increase in ED utilization has been concurrent with a decrease in the total number of EDs. From 1996 to 2006 the number of EDs in the United States declined 4.6%, from 4019 to 3833 (Figure 123-1).

Although increased utilization and constrained inpatient capacity are the predominant causes of ED crowding, demographic changes have also pressured ED capacity. The uninsured and the elderly, two groups of patients who tend to present with a high degree of acuity, are an increasing proportion of the patients treated in EDs. In 2006 uninsured patients accounted for 17.4% of all ED visits. In the same year patients over 75 years old were the age group with the highest per capita visit rate.

Shortages of several types of health care providers have further exacerbated the problem of ED crowding. The shortage of hospital-based nurses, estimated in July 2007 at 116,000, has left many EDs struggling to find full staffing. The well-publicized shortage of primary care physicians has left many patients with no choice but to use EDs for the initial evaluation of their medical condition, regardless of acuity. Less well publicized than nursing and primary care physician shortages is the shortage of surgeons and medical subspecialists willing to be available for calls and provide consultative or admitting services to the ED. Such physicians typically cite poor compensation and the threat of increased legal liability among their reasons for avoiding covering the ED.

Staffing models have not completely accommodated the needs of EDs, now the primary portal of entry into the hospital. Most hospitals are staffed around a traditional 8 am –5 pm, Monday through Friday model, with lower staffing during other times. Yet in 2006, 62.9% of ED visits occur outside of these hours with peak ED occupancy occurring at 7 pm. Scheduling of elective surgeries has also not evolved to accommodate ED needs. Most elective surgeries are front loaded during the week so that ancillary services such as physical and occupational therapy are available in the immediate postoperative period. This constrains operating room capacity on precisely the days that are busiest for EDs.

Shortages of inpatient hospital beds have paralleled those seen in EDs; high hospital census conditions limit patient flow out of the ED and hence further exacerbate ED crowding. The most frequent shortage of inpatient beds occurs in the nation's intensive care units (ICUs). One of the most frequent causes of delays in getting patients admitted from the ED is lack of ICU capacity. Across the country ICU occupancy rates at any given time are extraordinarily high, between 84% and 93% in various studies, and demand for ICU beds continues to increase. Lack of inpatient beds leads to “boarding” of admitted patients in the ED, which further restricts already constrained capacity and adversely effects clinical outcomes. The Institute of Medicine has challenged hospitals, and by extension hospitalists, to improve the flow of patients through the ED in order to eliminate ED boarding completely. Boarding and crowding have several negative consequences, including impaired flow of patients through the ED, decreased patient and provider satisfaction, poor clinical outcomes, and ambulance diversion to other less crowded EDs.

Predictably, flow of patients through the ED decreases as patient volume approaches and exceeds capacity. Under such conditions wait times for initial evaluation by a health care provider increase and the overall ED length of stay (ED LOS) increases. Although there has been significant attention to this problem over the last few years, a 2009 report by the General Accounting Office (GAO) entitled Hospital Emergency Departments: Crowding Continues to Occur and Some Patients Wait Longer than Recommended Time Frames illustrates that ED crowding continues as a significant issue. In 2006 patients needing immediate care waited an average of 28 minutes while those needing emergent care waited an average of 37 minutes, both exceeding time frames recommended by the National Center for Health Statistics (Table 123-1). In the same year the average ED LOS was 199 minutes, an increase of 12% from 178 minutes in 2001.

ED crowding also impacts overall hospital outcomes, including increased LOS and adverse events. A large, multicenter, cross-sectional study demonstrated that patients admitted to the ICU with a greater than six-hour delay in transfer from the ED had a significantly longer hospital length of stay and higher in-hospital mortality. In a second study increased ED LOS beyond eight hours added approximately 24 hours of total time in the hospital. Other studies have shown that patients boarded in the ED during times of crowding experience an increased number of adverse events.

EDs often resort to “diversion,” the practice of alerting local emergency medical services (EMSs) that they can no longer accept patients. Several studies demonstrate that patient diversion is associated with increased mortality. Diversion also costs individual hospitals approximately $1086 per hour in lost revenue. A recent study estimates that, on average, an ambulance is diverted once every minute in the United States, roughly half a million times per year.

Regulatory and Professional Pressures

Various regulatory and professional pressures on EM physicians may affect their clinical practice and also contribute to ED crowding, affecting patient flow within hospitals. Regulatory pressures include the Emergency Medical Treatment and Active Labor Act (EMTALA). EMTALA requires EDs, EM physicians, and on-call physicians covering EDs to provide a screening examination to any individual who presents to an ED and requests examination or treatment. A patient found to have an emergent condition must be treated until stabilized or transferred to another facility to receive treatment. According to EMTALA an emergency medical condition means a medical condition manifesting itself by acute symptoms of sufficient severity (including severe pain) such that the absence of immediate medical attention could reasonably be expected to result in placing the health of the individual (or, with respect to a pregnant woman, the health of the woman or her unborn child) in serious jeopardy, serious impairment to bodily functions, or serious dysfunction of any bodily organ or part.

Professional pressures affecting ED physicians include professional organization expectations, public expectations, and legal risks. The American College of Emergency Physicians (ACEP) Emergency Medicine Physician Performance Measure Set holds EM physicians accountable to consensus guidelines for a number of disease states. They address quality measures, such as aspirin on arrival for acute myocardial infarction, electrocardiogram (ECG) for syncope, and oxygen saturation (SpO2) evaluation and empiric antibiotics for community-acquired pneumonia (CAP). The Prudent Layperson Standard (advocated by ACEP) suggests that health care coverage in EDs should be based not on diagnosis but on symptoms since the public cannot be expected to self-diagnose. High legal liability occurs in the United States compared with other English-speaking nations. Compared with the United Kingdom and Australia, the United States has 50% more medical liability claims and 350% more than Canada. Unlike Australia the United States lacks federal policies that protect physicians from litigation, even for those patients covered under EMTALA.

In order to identify strategies for minimizing ED crowding patient flow can be categorized into three stages: input, throughput, and output (Table 123-2). Hospitalists should lead collaborative efforts to improve flow through the ED and can impact various aspects of the input-throughput-output model. Since they are increasingly tasked with admitting from outpatient clinics, hospitalists can diminish ED input by selecting appropriate patients for direct admission, bypassing the ED entirely. When asked to admit from the ED, hospitalists can improve throughput by assisting EM physicians with selection of specific diagnostic tests needed to determine disposition and with triage to the most appropriate level of care. Even when they are not asked to admit, hospitalists can offer their services as consultants to assist EM physicians in developing a care plan, including initiating directed treatment or specifying optimal follow-up for patients who may not require admission. At the output stage hospitalists can standardize and streamline their admission processes and policies. They should be well versed with national as well as institution-specific admission guidelines. Hospitalist and EM leaders should partner to provide ongoing education for physicians within their departments regarding accepted guidelines and clinical care practices.

Hospitalist-Based Studies

Interventions directed at the ED output stage—facilitation of transfer to the appropriate inpatient level of care and proper service—have shown compelling results. In one intervention known as active bed management, a bed manager role (staffed by a hospitalist) was created to allow broad authority to assign admissions to the Department of Medicine. The bed manager conducted twice daily “prediversion rounds” in the ICU to identify bed shortages, made regular visits to the ED to assess congestion, and in consultation with EM physicians helped coordinate transfer to the appropriate hospital location. EM physicians were asked to write holding orders for patients accepted but not yet admitted. In addition, a senior hospitalist (bed director) worked to adjust hospitalist physician staffing and coordinate acceptance of patients by specialty services when the ED either began to experience excessive patient time in the department or when it went on diversion. Using these strategies, throughput for admitted patients improved on average by 98 minutes per patient, and diversion due to lack of ICU beds decreased by 27%. Institution-specific needs and current models of care and flow would affect the value of such a model at other institutions, but some organizations may benefit from a bed manager role to improve ED flow.

Emergency Medicine–Based Studies

EM-led interventions targeting the throughput stage have met with mixed results. The utilization of a triage liaison an EM physician hired to evaluate patients in the triage area, traditionally the domain of triage nurses—decreased ED LOS by an average of 36 minutes. Left-without-being-seen (LWOBS) dropped from 6.6% to 5.4% (a 20% reduction). However, time spent on ambulance diversion did not change. The duties of the triage liaison included answering incoming calls from physicians, assisting the triage nurse, assessing ambulance patients, ordering diagnostic tests, and occasionally starting directed treatment.

Another EM-led initiative entitled the Rapid Admission Policy eliminates two constraints on output: the need for patients to be seen by accepting physicians in the ED and the requirement that all diagnostic tests be completed before admission. Under this protocol once EM physicians determined that admission was necessary, a consensus inpatient location was decided upon in collaboration with the admitting physician, and the ED physician was tasked with writing brief holding orders. Once holding orders were complete, admission could not be delayed assuming a bed was available. As a result ED LOS dropped by 10.1 minutes, which, although seemingly a small improvement, actually decreased weekly minutes on diversion by 169 minutes (65%) and increased facility charges by 3.2%.

At a busy Canadian hospital a full-capacity protocol (“surge plan”) was implemented to admit low-acuity patients boarded in the ED to inpatient hallways, thereby spreading the burden of boarding among different services and locations within the hospital. EM physicians coordinated with the admitting physician (usually a hospitalist) the decision about which patients to admit to floor hallway spots. Using this protocol ED LOS was reduced by five hours per patient. Inpatient hallway boarders had a hospital LOS one day less than their counterparts boarded in the ED; and ICU transfers and mortality were higher for patients admitted to traditional beds (hospital rooms) than for those boarded in hallway spots. However, these latter findings likely reflect selection bias rather than a clinical benefit of hallway boarding.

Based on these studies and others ACEP in 2008 identified several hospital-based solutions for ED crowding, which are likely to involve hospitalists. They have categorized these solutions into those that they consider highly effective, those that may have some efficacy, and those that have been proven ineffective (Table 123-3).

Other Potential Solutions

Another valuable opportunity to improve coordination of care between the ED physicians and hospitalists arises from the Emergency Severity Index (ESI).2 The ESI is a validated triage algorithm championed by the Agency for Health Research and Quality (AHRQ) that provides stratification of patients into five groups from 1 (most urgent) to 5 (least urgent) on the basis of acuity. It was designed specifically to improve reliability and validity of triage decision making in the ED, has high interrater reliability, and has been correlated to resource utilization and mortality. This tool has been shown to be an excellent predictor of both hospital admission and ICU admission (Table 123-4).

Admitting hospitalists and hospitalist bed managers can use this ESI acuity scale to anticipate floor bed and ICU bed needs. Many EDs report the ESI score on ED electronic patient boards. EM physicians can likewise alert hospitalist leadership when a large number of patients with ESI levels 1 through 3 patients are pending evaluation.

Recently, medical informatics companies have turned their attention to the issue of active bed management. Some products provide real-time assessment of bed availability and allow for more efficient patient flow and increased patient safety. Such systems typically use enterprise-wide electronic bed boards, similar to what is seen in many EDs, and simple color coding to indicate which rooms are available, occupied, or need to be cleaned. Such systems may improve overall inpatient flow of patients, and in turn ED flow.

Patients who require admission but have not left the ED due to hospital space constraints or bed availability limitations are considered “boarded” in the ED. The number of boarded patients within the ED typically increases with a higher ED census when ED staff members have to prioritize their attention to the most acute patients and to those without a care plan. Because boarded patients are physically distant from their provider of record (admitting physician), and because the “ownership” or responsibility for caring for the boarded patients is generally poorly delineated, boarded patients may receive less than optimal care. Boarders may negatively impact the care of other patients by consuming limited physical and personnel resources. Since the majority of admissions through EDs are for medical conditions, the majority of boarded patients are typically admitted to hospitalists who thus have a vested interest in addressing the problems of ED crowding and boarding.

Improving Communication

While hospitals strive to eliminate the practice of ED boarding, hospitalists can take steps to minimize boarding and improve the care of these patients. In collaboration with the ED staff, hospitalists can develop protocols that improve their care and standardize communication during a critical transition or hand-off of care from the ED to the inpatient setting. According to The Joint Commission, problematic communication is the root cause of most medical errors, adverse events, near misses, and sentinel events.

Researchers have identified several factors that can degrade the quality of the emergency physician-hospitalist hand off process:

1. Physicians from both disciplines tend to allocate inadequate time for hand-off.

2. Based on their differing needs, EM physicians and hospitalists have very different expectations for hand-off communication.

3. Hand-off occurs in a chaotic, crowded setting that is full of distractions (eg, consultant phone calls, ambulance deliveries, codes).

4. Hand-off may occur several times on a single patient when hospitalists and EM physicians change shifts or when house-staff are involved.

5. Group affiliation, which leads physicians to conform to the opinion and behavior of others within their own specialty, causes communication between specialties to require extra effort.

6. In-group and out-group biases engender mistrust.

7. Hierarchical relational issues exist between attending physicians and house staff and between senior and junior staff.

This and other research has led to several potential strategies for improving communication between hospitalist and EM providers (Table 123-5).

The term triage originates from the French verb trier, meaning to sort. Its medical usage dates from the Napoleanic Wars when a Hôpital de Triage was employed as a sorting station for injured soldiers. In modern hospitals triage is the process of determining the most appropriate disposition for a patient based on the nature and severity of their illness and on hospital resources. Triage typically includes a decision about whether to admit a patient to the hospital and if so, to which clinical area and service (eg, Hospital Medicine, Surgery).

Triage complexity increases with increasing illness severity; thus patients being considered for ICU admission can present a particular challenge. Nationally accepted guidelines for ICU admission do not exist, and mortality prediction models such as the Acute Physiology and Chronic Health Evaluation IV (APACHE IV), Mortality Probability Models II (MPM II), and Simplified Acute Physiology Score (SAPS II) unfortunately have poor utility in predicting which patients should be admitted to an ICU, since all of these prognostic models were developed based on patients already in the ICU.

The most widely used framework for determining the appropriateness of ICU admission is based on the Society of Critical Care Medicine's (SCCM) Guidelines for intensive care unit admission, discharge, and triage, published in 1999. These guidelines implicitly acknowledge the difficulties in triaging critically ill patients by proposing three different models based on patient prioritization, diagnosis, or objective parameters. The prioritization model divides patients into four categories: those who need intensive monitoring and treatment (most often those requiring vasoactive drugs or mechanical ventilation), those who need intensive monitoring and may need immediate intervention, patients who are unstable but have a reduced likelihood of recovery, and those who are too well or too sick to benefit from intensive interventions.

Whatever model or combination thereof is used, explicit written institutional policies must exist in order to avoid confusion and to encourage consistency of practice. These policies should be made public and discussed with critically ill patients or their surrogates. Administration, nurses, support staff, and physicians should collaborate on institution-specific policies regarding ICU use. Overflow policies must also be clearly defined and readily available. The hospital should assign triage responsibilities to a single individual, with performance overseen by a multidisciplinary critical care committee. This committee should have oversight of all of the hospital's ICUs and their directors and should regularly review ICU denials and ICU rapid return or rapid readmission patients.

The Ethics Committee of SCCM in their Consensus Statement on the Triage of Critically Ill Patients states that providers of critical care must use some moral framework for distributing limited resources efficiently and equitably, since demand will frequently exceed supply. By necessity, in an equitable system ICU care must be restricted. Decisions should be based on the concept of medical justice, such that limited resources are allocated to those most likely to benefit from their use. Such patients should have a reasonable expectation of substantial recovery, as recommend by the Consensus Statement. Patients who are not expected to benefit should be excluded. That includes both the too-well-to-benefit and too-sick-to-benefit categories. The too-sick-to-benefit category includes not only those with end-stage chronic disease but those with irreversible conditions such as metastatic cancer unresponsive to chemotherapy, severe ischemic or anoxic brain damage, and irreversible multiorgan failure. When a patient has become critically ill with a chronic disease the desirability of ICU care should be discussed with the ICU director, the EM physician, and the patient's family at the time of initial presentation. This discussion should include specific reference to triage policies.

The role of the ICU director, often a critical care trained intensivist, should be separated from that of the triage clinician as much as possible to avoid conflicts of interest. SCCM also recommends that the ICU director have no other clinical responsibilities.

Triage of Surgical Patients

For the sake of expediency hospitalists are sometimes asked to fill the gaps when providers in certain specialties are not immediately available or responsive to ED needs. Particularly common is the request by EM physicians to hospitalists to admit patients with surgical problems. Despite the increasing trend for such admissions, hospitalists often fear legal liability when managing patients with a primary surgical diagnosis. Hence, triage decisions for patients potentially needing surgery should follow the simple principle of placing the patient on the service where the patient will receive the most appropriate care. Oftentimes, this determination can only be made once both surgeons and hospitalists have made an in-person evaluation of the patient. In addition, the role of nursing should not be overlooked. Patients with a primary surgical diagnosis may benefit more from the care provided by surgical nurses, irrespective of who is the attending of record. Likewise, patients with a primary medical diagnosis driving admission may benefit more from the care provided by medical nurses, even if it is anticipated that they will eventually require surgery.

When the decision is made for a patient to be co-managed by surgery and Hospital Medicine, roles and responsibilities of each service must be agreed upon at the outset of care. Are the patients going to be truly co-managed where each service has the authority to write orders? or is one service or the other going to act strictly as a consultant making recommendations only? Hospital policies for the delineation of responsibilities for such patients are essential. A case-by-case approach burdens the EM physician with multiple phone calls and slows throughput. One solution that may permit more immediate evaluation and management by surgeons involves use of acute care surgeons (surgeons who spend their time caring for hospitalized patients, sometimes called surgical hospitalists or surgicalists).

Disease-Specific Considerations

Disease-specific prediction models are more accurate than general guidelines in predicting need for ICU admission. Specific criteria exist only for a few medical conditions, such as gastrointestinal hemorrhage (the BLEED criteria) and pneumonia (CURB-65, Pneumonia Severity Index, SCAP score). A hospitalist should incorporate these prognostic criteria or guidelines into practice when applicable. Sepsis remains a common and life-threatening reason for presentation to the ED. Extremely common, simple sepsis is associated with low to moderate mortality risk (˜16%), and may require ICU admission at presentation, but in many cases may be safely managed in the non–critical care setting. On the other hand, severe sepsis (sepsis associated with end-organ damage or hypotension) and septic shock (severe sepsis with hypotension and tissue hypoperfusion unresponsive to significant volume challenges) have an associated mortality of approximately 30% and 50%, respectively. These latter two groups of patients have unstable physiologic or hemodynamic parameters and should be admitted to the ICU, barring unusual circumstances.

Observation Units

The Institute of Medicine's 2007 report, The Future of Emergency Care: Hospital Based Emergency Care at the Breaking Point, offers several suggestions to improve the efficiency of hospital-based emergency care. The use of “Observation Units” or “Clinical Decision Units” to manage patients following their initial ED evaluation allows additional time to perform diagnostic studies or discreet time-limited management according to specific entry criteria. Such additional time can help determine the need for inpatient admission or early discharge.

Observation patients are defined by the Centers for Medicare and Medicaid Services (CMS) as those patients needing further evaluation “to determine the need for inpatient admission.” CMS explicitly states that most patients will require less than 24 hours to reach this goal. Alternatively, admission review guidelines such as those published by InterQual define inpatient or observation status. By design InterQual guidelines review patient criteria for admission on a retrospective basis, whereas the CMS policy evaluates patient admission criteria prospectively. Observation patients may be best understood when considering patient lengths of stay. The Centers for Disease Control and Prevention (CDC) has reported that admitted ED patients will spend roughly five hours in the ED. Hospitals are often scrutinized for inpatient admission of one day or less, as many of those patients should have been classified as “observation” status, even though they occupy an inpatient bed.

There remains a distinct group of ED patients who clearly need more than 5 hours, but less than 24 hours, to address their clinical needs. These are the “6- to 24-hour” patients. Several prospective, randomized, controlled trials have shown that the length of stay and costs of these patients will double or triple if they are admitted to a traditional inpatient ward rather than an observation unit. Such patients will exacerbate ED overcrowding if they complete their evaluation in the ED, and they cannot be discharged without potential risks. A dedicated observation unit for appropriately selected patients can improve patient satisfaction, lower rates of missed myocardial infarction, lower diagnostic uncertainty, decrease ED and hospital overcrowding, improve diagnostic test completion rates, and maintain clinical outcomes comparable to those for patients admitted to the hospital.

While observation units have been around nearly as long as EDs, it is only in the last two decades that protocol-driven units have been described. Initially units were primarily focused on patients with chest pain, subsequently giving rise to “chest pain centers.” Based on clinical studies, observation units have expanded into protocols for asthma, syncope, heart failure, atrial fibrillation, and transient ischemic attacks. By design observation units are also well equipped to manage patients with dehydration, abdominal pain, renal colic, and a variety of infections. Nationally, 31% of U.S. hospitals either utilize or plan to implement an observation unit. The observation unit truly represents an interface between EM and Hospital Medicine. Fifty-three percent of observation units are geographically located within or adjacent to the ED, with the remainder either in the hospital or in both locations. Admission privileges to the unit may be “open” to any hospital physician, or “closed” and limited to only one specialty group. That group may be the EM group or Hospital Medicine group, depending on local practices. Regardless of the model, Hospital Medicine and EM need to collaborate to optimize clinical care and patient flow. Some units operate as a “hybrid” unit, caring for observation patients as well as scheduling outpatient procedure patients. This model offers the advantage of a more robust unit census, with observation patients filling the unit during the evening hours, and scheduled procedure patients filling the unit during daytime hours. This model has also been shown to improve nurse utilization for a smaller unit (3.7 vs 2.5 patients/nurse/hour).

Basic principles for the operation of an observation unit have been described by ACEP. Because the unit is designed for this specific patient population, its use should ideally be limited to patients with a well-defined reason for observation, or a working diagnosis or condition. That condition may involve a diagnostic evaluation for a potentially serious diagnosis, therapy of an acute medical condition, or management of acute psychosocial needs. Diagnostic conditions should represent a balance between the potential morbidity and mortality of the condition and the probability that the condition will be confirmed. For example, evaluation of patients with chest pain for possible acute coronary syndrome (ACS), which (if diagnosed) bears a 25% short-term adverse outcome likelihood, is often limited to patients with lower probability of disease (7% or less).

The patient's severity of illness and intensity of service requirements should be low enough to match the resources available in the observation unit. Patients actively managed in observation units have an average length of stay of 15 hours. Units are often located within or adjacent to the ED since most patients arrive from the ED. When units are remote from the ED, it becomes logistically difficult for ED physicians to participate in the care of the patient. On average, observation units are staffed with one nurse per four patients, and 20% of such units employ nurse practitioners or physician assistants. Care is best facilitated through the use of guidelines for both unit operations and the management of specific conditions developed through background research and collaboration with other relevant departments. Condition guidelines often include inclusion and exclusion criteria, interventions permitted in the observation unit, and criteria for discharge or hospital admission. From these guidelines, protocol orders may be developed. Since the observation unit functions as a limited resource within the facility and may be used as an alternative to admission, its use, processes, and outcomes require intensive and frequent review for utilization and quality. Utilization may include census, case mix, length of stay, and admission rate. Quality audits may include protocol use rates, patient satisfaction, ED or hospital return visits, hospital admission rates, ICU admission rates, and mortality. Finally the observation unit should remain cost effective and efficient for the hospital, providers, and patients.

ED crowding has become a challenging feature of the landscape of U.S. health care. The need to improve patient flow through the ED in order to alleviate crowding and minimize the practices of boarding and diversion has led EM physicians and hospitalists alike to search for solutions. This search has brought increased awareness of the need for improved communication and greater coordination of care. Several strategies to improve ED throughput include development and use of transparent and readily available guidelines for the triage of surgical and critically ill patients and the use of ED based observation units. In the event that patients do become boarded in the ED, this chapter provides suggestions for how to effectively co-manage patients until they can be placed in inpatient beds.