EMS Perils from Hospital Overcrowding
A 71-year-old man with a history of postoperative septic knee arthritis (status: post-intravenous antibiotics) presented to a hospital-based orthopedic surgery clinic for a follow-up evaluation of his knee. At this same appointment, the patient complained of pain and swelling in his right shoulder. His shoulder joint was found to be acutely inflamed; 10 cc of purulent fluid was aspirated from his shoulder during that appointment. The clinician suspected septic arthritis and sent the patient to the Emergency Department (ED) via ambulance for evaluation and treatment by the inpatient orthopedic surgery team. That inpatient team was made aware of this patient coming to the ED from the clinic and admission orders were entered into the electronic health record (EHR) before he arrived at the ED, following standard practice. However, the ED staff were not informed of the incoming patient or the orthopedic surgeon’s plan for immediate admission.
When the patient arrived at 19:40, the ED was severely impacted with a high volume of patients in the waiting room and multiple boarding patients awaiting inpatient beds. The patient stayed in the ED hallway on “wall time” under the care of the Emergency Medical Services (EMS) personnel despite being physically inside the ED. No ED physician or nurse was assigned to evaluate or care for the patient because the transfer of care from EMS had not occurred. Because the ED was not notified that this patient was being sent by ambulance from a medical office (a routine practice in most communities), it was assumed the patient should be “admitted” to the ED and have a medical screening exam. The patient was on wall time for at least 10 hours before any actions were taken by the ED.
The patient was admitted to the orthopedic inpatient service and taken to the operating room on hospital day #2 for incision and drainage of right shoulder pyogenic arthritis and periprosthetic joint infection. Fluid cultures were negative but presumed to be the same species (Methicillin Sensitive Staphylococcus Aureus) grown from his knee pyogenic arthritis a few weeks prior. He was started on intravenous Cefepime and discharged on hospital day #14 on intravenous Cefazolin and oral Rifampin.
By Samantha Brown, MD, John S. Rose, MD, and David K. Barnes, MD
This case highlights several related patient safety issues that can arise when a patient is transferred by Emergency Medical Services (EMS) from an outpatient clinic to a hospital’s Emergency Department (ED). It is the opinion of the authors that the most critical safety issues identified in this case include 1) the harmful effects of hospital and ED crowding on patient safety, 2) the necessity for a safe and effective EMS-to-ED transition of care (i.e., handoff), and 3) the importance of effective communication between an outpatient clinic and ED staff when patients are referred or transferred to the ED for evaluation or admission.
Hospital crowding is emerging as an important theme in relation to patient safety. Hospital crowding, commonly referred to as ED crowding even though the underlying cause is often the inability to find open inpatient beds for admitted patients, has led to a phenomenon known colloquially as EMS “wall time.” Officially termed Ambulance Patient Offload Time (APOT) by the California Health and Safety Code, wall time is defined as the “time (in minutes) from time ambulance arrives at the hospital until the patient is transferred to hospital emergency department care.”1, 2 Operationally, wall time occurs when patients have arrived at the destination ED yet they remain under the care of EMS providers because there are no available beds, staff, or both to receive them. A contributor to this problem is the fact that the number of visits to EDs in US hospitals over the past two decades continues to rise despite the number of ED beds remaining relatively stable or declining.3,4 The result is hospital crowding with more frequent occurrences and longer episodes of EMS wall time. While EMS wall time is not unique to California, herein the authors will describe the effects of wall time as experienced in their California ED, which is based at an urban, academic, level-1 trauma center, comprehensive stroke center, burn center, and comprehensive pediatric hospital.
Making matters worse, legal responsibility for patients on wall time —either the EMS providers who remain with the patient prior to a formal care transition, the ED staff, or the hospital upon whose physical property the patient is located—is poorly defined.5 Although both the EMS system and ED environments are highly regulated, patients on wall time comprise a novel and uncharted intersection between responsibility for patient care and physical location that is often interpreted extemporaneously, leading to interprofessional conflict, regulatory and malpractice risk, and poor patient outcomes.6-8
The ED Admission Process
What happens when a person or clinic calls 9-1-1 and a patient is transported to the Emergency Department?
In the United States, 9-1-1 calls are answered by a Public Service Answering Point (PSAP) which are nearly all managed through law enforcement dispatch centers. Depending on the size of the 9-1-1 jurisdiction, a PSAP operator will route the call to police, fire, or emergency medical dispatcher (EMD) who then assess the medical requirements, routes appropriate medical assets, and provides pre-arrival instructions to the caller.9 Not all ambulances on the road are equal. Some are staffed solely with Emergency Medical Technicians (EMTs) who have limited scope of practice and are typically transporting stable, low acuity patients to pre-scheduled appointments or the Emergency Department. Most ambulances responding to 911 calls are staffed with a Paramedic who possess a broader scope of practice and provides Advanced Life Support (ALS) interventions such as airway management and administration of intravenous fluids and medications in order to stabilize patients while transporting them to an ED.10
When an ambulance arrives on the scene of a 9-1-1 call, the EMS providers perform a preliminary assessment to determine if the patient requires transport to an ED and if that ED should be located at a specialized receiving center such as a trauma, cardiac, or stroke center. After that assessment, a patient can either decline transport against medical advice (AMA) or be transported to an ED. Existing California regulations do not allow ambulances to transport patients to lower acuity, non-ED facilities such as urgent care centers or outpatient clinics if the service was activated through the 9-1-1 system. However, many state legislatures are considering allowing ambulances to transport stable, low acuity patients to alternate destinations as a means to reduce hospital crowding.10 Studies of the use of such exceptions have been promising.11-18
What is required when a patient “comes to an Emergency Department”? Does it matter if a patient comes to an ED via EMS or by some other means?
What makes a facility an Emergency Department? While minor differences exist across various states and counties, EDs are generally required to offer emergency services 7 days a week, 24 hours per day; to have equipment, medication and personnel experienced in the provision of emergency medical services needed to treat life-, limb- or function-threatening conditions; to have diagnostic radiology and clinical laboratory services provided by persons on duty or on call when needed; to have at least one physician trained and experienced in the provision of emergency medical care who is on duty or immediately available to the facility; to have a roster of specialty physicians who are available for referral, consultation and specialty services; and to have transfer agreements in effect wherein patients requiring more definitive care will be expeditiously transferred and receive prompt hospital care.10,19
When a person presents to a qualifying ED by ambulance or private vehicle and requests examination or treatment for an emergency medical condition (EMC), that person becomes a patient, and their care is regulated by the federal Emergency Medical Treatment and Active Labor Act (EMTALA) of 1986.19 Pursuant to EMTALA, and with only a few specific exceptions (e.g., legally authorized phlebotomy for evidentiary blood alcohol determination), every ED in the United States is required to offer a patient a medical screening examination (MSE). The MSE must be performed by a qualified medical provider, such as a physician or advanced practice practitioner, as designated by each facility. The purpose of the MSE is to evaluate for the presence of an EMC which, if present, must be appropriately stabilized or, if the facility is unable to provide stabilizing treatment, the patient must be transferred to a facility that can. EMTALA was established as a remedy to blatant financial discrimination by preventing “dumping” of low-income patients on underfunded public hospitals.20
EMTALA defines an MSE as a “medical exam of sufficient scope as to be reasonably intended to determine whether an emergency medical condition exists and includes all necessary testing and on-call services within the capability of the hospital to reach a diagnosis that excludes the presence of legally defined Emergency Medical Conditions.”21Critically, there is no minimum number of diagnostic studies (e.g., labs or imaging) that determines the completeness of an MSE. Rather, the MSE is unique to each individual presentation, as is the testing necessary to reach a diagnosis. EMTALA further requires that appropriate treatment be initiated and the patient be stabilized prior to discharge. If a patient is diagnosed with an EMC, that condition must be stabilized, or the patient must be admitted or transferred to a facility with appropriate capabilities. An EMC is statutorily defined by EMTALA as:
(1) 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:
(i) 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.
(ii) serious impairment to bodily functions, or
(iii) serious dysfunction of any bodily organ or part; or
(2) With respect to a pregnant woman who is having contractions -
(i) there is inadequate time to affect a safe transfer to another hospital before delivery, or
(ii) transfer may pose a threat to the health or safety of the woman or the unborn child.19,21
This definition leaves a treating provider with a fair amount of uncertainty as to whether a patient’s presenting symptoms qualify as an EMC and what workup is necessary to appropriately stabilize their condition. Accordingly, EMTALA defines stabilization as “such medical treatment of the condition as may be necessary to assure, within reasonable medical probability, that no material deterioration of the condition is likely to result from or occur during the transfer of the individual from a facility.”21 The best approach is to follow all applicable standards of care most appropriate to that presenting condition.
Regardless of a patient’s mode of arrival, once a patient is physically on hospital property—defined as the area within 250 yards of the principal building facility or within a hospital-owned ambulance or air ambulance, regardless of location—EMTALA applies and the responsibility for the patient’s care transitions to the hospital.22 This legally defined transition of patient care upon arrival to hospital property makes the concept of “wall time” problematic and controversial given that patients on wall time are still operationally under the care of EMS providers.
What defines the transfer of care from EMS to the ED/hospital?
Various jurisdictions define transfer of care from EMS to the ED or hospital differently. In 2016, the California EMS Authority (EMSA) released an Interim Guidance Memo related to APOT wherein the transfer of care was defined as “an event that includes BOTH the completion of triage at the hospital emergency department AND acceptance of the patient by the ED staff from the EMS ambulance staff,” which is generally regarded as the “time the patient is physically moved from the ambulance gurney onto hospital equipment.”23 Given this definition, many EMS agencies require their personnel to obtain the signature of an accepting hospital or ED representative to indicate a formal transition of care.24 Although a hospital legally assumes responsibility for patients once across the 250-yard perimeter of the main facility building, safe patient care requires a formal transition of care when EMS personnel are able to transfer the patient to a hospital gurney.22 However, this usual and customary practice has been adversely affected by hospital crowding, leading to frequent delays in ambulance offload times.
Transitioning patient care from the pre-hospital environment to the ED environment is an important event in the patient’s medical journey. Critical information from bystanders, family, or sending facilities (among others) may determine the course of a patient’s EMC and the eventual outcome for a patient. Curiously, statutory requirements detailing the components of an EMS-to-ED transfer of care do not exist in many jurisdictions. As a result, there is substantial variance in the quality of information passed from EMS to the ED. In our opinion, this represents an important opportunity for process improvement.
What happens if the ED is busy and doesn’t have a bed for the ambulance to transfer the patient?
Over the last two decades, hospital crowding has emerged as a public health crisis.4 This problem was first described in the 2003 US General Accounting Office Report citing an increase in ED visits from 95 million in 1997 to 108 million in 2000.6 When hospitals are operating near full capacity, EDs are unable to move admitted patients to inpatient beds. In turn, EDs then reach their full capacity and are unable to accommodate ambulance patients brought by EMS. More recently, another study found that 90% of EDs across the nation reported ED crowding to be an issue in their facility.15 This crisis has proven to have negative effects on patient care. ED crowding has led to a dose-response increase in all-cause 30-day mortality and one preventable death for every delay of greater than eight hours in physically moving a patient out of the ED.25 The burden of ED crowding necessarily spills over to EMS providers as longer wall times leave them feeling that they are “held hostage” at hospitals waiting for the transition of their patients’ care to the ED.26 EMS response time to new 9-1-1 calls may even be adversely affected.27
Interestingly, there is no federal statutory or regulatory requirement for EMS providers to hand off a patient to a hospital or ED provider. Rather, EMS providers are regulated by the policies and procedures of their state government and specific local EMS agencies (LEMSAs), which often operate at the county level. LEMSAs, under the authority of local EMS Medical Directors, establish policies, protocols, and procedures that EMS providers follow while working within their jurisdiction.10 Many LEMSAs in California expect their EMS providers to wait with an ambulance patient and provide ongoing care until an appropriate transition of care to the ED occurs. While there is no legal requirement for EMS providers to do so, they do have an ethical obligation to continue providing care until an appropriate handoff occurs. Moreover, the threat of an abandonment or negligence lawsuit dissuades many EMS providers from leaving before a formal EMS-to-ED transition.24 This issue is increasingly relevant as hospital and ED crowding have caused longer wait times for EMS providers. Delaying ambulance offload and “refusing to release EMS equipment or personnel jeopardizes patient health and impacts the ability of EMS personnel to provide emergency services to the rest of the community."3 Whether delaying ambulance offload and care transition violates EMTALA remains uncertain.3
This problem is not unique to California, and other states and countries have attempted to address it legislatively. In 2005, Nevada established a 30-minute maximum standard for the transfer of care of an ambulance patient to the hospital.3 Similarly, the British National Health Service (NHS) Confederation recommended “zero tolerance” for ambulance transfer delays and established a national standard of 15 minutes or less for ambulance transitions.3 The NHS took the extra step of levying financial penalties on hospitals that do not meet the 15-minute standard 85% of the time and a separate 30-minute standard 95% of the time.3
Hospitals, EMS agencies, and EMS providers have scrambled to find solutions to the growing burden of wall time.28,29 Some pre-hospital organizations have established a Medical Duty Officer position, a senior paramedic who works in conjunction with dispatch centers to collect ED traffic information in real time and then appropriately triage and disperse patients to hospitals with capacity to receive them.12 At the hospital level, direct admissions allow patients to bypass the ED altogether, but this process may also contribute to hospital crowding and may negatively affect quality of care. For example, patients who are directly admitted for treatment of sepsis were found to have increased mortality compared to those admitted through the ED.14 Another approach has been to move ED patients who are admitted to inpatient hallways. Implementation of this initiative, originally referred to as the “Stony Brook” model, has been shown to increase patient satisfaction and reduce discharge completion times.6
California law requires that EMS providers transport all 9-1-1 patients to an ED unless the patient refuses care at the scene.10 Although most ambulance patients require ED services, others could be treated at urgent care centers or primary care clinics, or do not require care at all. Consequently, it has been proposed that EMS providers be allowed to transport low acuity patients to one of these “alternate destinations” to decrease ED volumes.30 These proposed solutions have shown promise but have not been studied rigorously enough or implemented at scale.17 As ED volumes and EMS wall times worsen, it has become apparent that an urgent solution is necessary.
When a patient is transported by EMS to a hospital, does care have to transition to the ED or can transfer to any hospital staff suffice?
There is a lack of clarity as to precisely how and when care transitions from EMS to the hospital and ED. Under EMTALA, when a patient arrives to an ED, a qualified medical provider is obligated to perform an MSE. According to the Centers for Medicare & Medicaid Services (CMS), each hospital formally determines who is qualified to perform an MSE.7 The MSE has traditionally been performed by an emergency medicine physician, but some institutions now include Advanced Practice Providers (APPs) as qualified providers. CMS has specified that non-physicians assigned to this role must be listed in documentation approved by the governing body of the hospital, not by “informal personnel appointments that could frequently change.”7 This regulation would allow for inpatient providers to perform the MSE when a patient arrives for direct admission, assuming those providers were listed in appropriately approved documentation. In the present case, inpatient orders were submitted for a patient who was intended for direct admission but, rather than bypassing the ED for an inpatient bed, the patient remained on EMS wall time in the ED. The admission orders created the potential for a violation of EMTALA had the patient been taken to an inpatient bed prior to having an MSE.
Approach to Improving Patient Safety
How can communication between outpatient clinics and the ED be improved to smooth transitions of patient care?
Although processes for improving communication between outpatient clinics and EDs exist, and it is customary at some clinics to alert the ED when a patient is referred for evaluation, there is no legal requirement for outpatient clinics to communicate directly with an ED about a patient referred for treatment. However, it is common knowledge that good communication between providers improves patient care, especially in the ED environment where patients are often unable to provide their own important medical history and ED providers have to make rapid decisions. Interestingly, having an EMS provider as an intermediary communicator can be beneficial, by providing a conduit for information between the clinic and the ED, or detrimental, as some studies have shown that information can be lost when a patient is transferred from a clinic provider to ED staff via EMS.29
Centralized communication systems can eliminate the need for an intermediary and reduce the chances that important clinical information is lost. In our health system, we developed an ED referral protocol for outpatient providers using our electronic health record (EHR) platform. Previously, outpatient providers would call the ED and provide information that was written down on paper and handed to the charge physician by the unit assistant. However, the charge physician would not necessarily evaluate and treat that patient, and the treating provider often never received the hand-written referral. Our new referral order allows the referring clinic provider to enter critical information (including copying and pasting previous history from the EHR) and share recommendations or requests for specific treatment plans in a narrative that is viewable by any ED provider who cares for the patient. An automatic pop-up banner alerts every provider who accesses the chart about the referral from the clinic. Not only has this process reduced the administrative burden on the unit’s staff—none of whom have a clinical background—but it has also improved efficiency and reduced loss of clinical information from referring providers.
Clarifying roles and responsibilities
While the ultimate responsibility for any patient on hospital property lies with the hospital, EMS wall time has become an area of significant controversy. Pursuant to EMTALA, when a patient arrives within 250 yards of the principal facility seeking evaluation or treatment for a medical condition, the hospital is responsible for performing the MSE and all necessary stabilizing treatment.5 However, as a consequence of hospital crowding and as described in the current case, EMS providers now find themselves providing extended care of transported patients while they are within the walls of the ED.
In this situation, EMS providers follow standardized treatment protocols approved by their LEMSA’s Medical Director. The EMS provider must communicate with the designated base hospital within their area of operation and discuss the case with the medical control base physician if they wish to deviate from a protocol or if other medical advice is requested. This presents a safety issue as the base hospital may be miles away from the one at which the patient is physically located and thus the base hospital physician is unable to see or examine the patient. While it seems obvious that an ED provider where the patient is physically located would be best positioned to provide the requested medical direction under these circumstances, consistent with EMTALA, this scenario is not currently codified in California law and EMS personnel cannot be expected to take medical direction from ED personnel who are not yet willing to assume responsibility for the patient. To ensure patient safety, these roles and responsibilities must be clarified within each jurisdiction.
In the current case, the patient was evaluated by an admitting inpatient provider and the patient received prompt admission orders; therefore, it does not appear that any financial discrimination or “dumping” occurred. Yet, while the patient was on wall time, he had not yet transitioned formally from the EMS provider to an ED and/or hospital provider, so inpatient orders and interventions could not be implemented even though the orders had been entered. Although the patient did not suffer any clear complications from this delay, the outcome could have been worse.
Most importantly, interventions addressing hospital and ED crowding, as described above, are urgently needed in many communities. When hospitals and EDs have the capacity to receive ambulance patients without delay, safe transitions of care can occur and there is no uncertainty regarding who is responsible for the patient’s care.
- EMTALA mandates that every patient who comes to an ED be evaluated by ED/hospital staff for an emergency medical condition and receive stabilizing treatment. If a patient cannot be stabilized, they must be admitted or transferred.
- EMS providers often encounter busy EDs, and “wall time” is the inevitable result of a supply-demand mismatch of healthcare resources that negatively affects patient safety, patient experience, and the morale of hospital staff.
- There is no statutory or regulatory requirement that EMS providers formally transition care when they arrive with a patient to an ED. However, EMS agencies may have local policies that require this, and formal transfer of care should be viewed as “best practice.”
- Potential system-level solutions to the “wall time” problem have shown promise in local studies, but have not been evaluated rigorously and at scale:
- Pre-hospital organizations may establish a Medical Duty Officer position, a senior paramedic who works in conjunction with dispatch centers to collect ED traffic information in real time and then appropriately triage and disperse patients to hospitals with capacity to receive them.
- Direct admissions allow patients to bypass the ED altogether, and appear to be permissible under EMTALA, but may contribute to hospital crowding, may lead to population-level health inequities, and may negatively affect quality of care.
- ED patients may be admitted to inpatient hallways when an inpatient bed is available, although this practice may place undue burden on inpatient staff.
- EMS providers may be allowed to transport low acuity patients to “alternate destinations,” such as urgent care centers, to decrease ED volumes.
- For patients who are sent to the ED from an outpatient clinic, centralized communication through the EHR may eliminate the need for EMS providers to serve as a conduit for information, freeing them up to leave the ED more quickly, and improving patient outcomes by providing a more direct patient handoff from the transferring provider.
- It is imperative that all stakeholders develop closed loop communication systems to minimize impact on patient care. Lack of communication can result in severe care delays such as the one in this case presentation. Loss of clear communication is a common theme when a system is overloaded.
Samantha Brown, MD
Emergency Medical Services (EMS) Fellow
Department of Emergency Medicine
UC Davis Health
John S. Rose, MD, FACEP, FAEMS
Prehospital Medical Director
EMS Fellowship Director
Department of Emergency Medicine
UC Davis Health
David K. Barnes, MD, FACEP
Health Sciences Clinical Professor
Department of Emergency Medicine
UC Davis Health
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