Emergency Department Surge Capacity: Recommendations of the Australasian Surge Strategy Working Group

For more than a decade, emergency medicine (EM) organizations have produced guidelines, training, and leadership for disaster management. However, to date there have been limited guidelines for emergency physicians (EPs) needing to provide a rapid response to a surge in demand. The aim of this project was to identify strategies that may guide surge management in the emergency department (ED). A working group of individuals experienced in disaster medicine from the Australasian College for Emergency Medicine Disaster Medicine Subcommittee (the Australasian Surge Strategy Working Group) was established to undertake this work. The Working Group used a modified Delphi technique to examine response actions in surge situations and identified underlying assumptions from disaster epidemiology and clinical practice. The group then characterized surge strategies from their corpus of experience; examined them through available relevant published literature; and collated these within domains of space, staff, supplies, and system operations. These recommendations detail 22 potential actions available to an EP working in the context of surge, along with detailed guidance on surge recognition, triage, patient flow through the ED, and clinical goals and practices. The article also identifies areas that merit future research, including the measurement of surge capacity, constraints to strategy implementation, validation of surge strategies, and measurement of strategy impacts on throughput, cost, and quality of care.     

Research Priorities for Surge Capacity

The 2006 Academic Emergency Medicine Consensus Conference discussed key concepts within the field of surge capacity. Within the breakout session on research priorities, experts in disaster medicine and other related fields used a structured nominal-group process to delineate five critical areas of research. Of the 14 potential areas of discovery identified by the group, the top five were the following: 1) defining criteria and methods for decision making regarding allocation of scarce resources, 2) determining effective triage protocols, 3) determining key decision makers for surge-capacity planning and means to evaluate response efficacy (e.g., incident command), 4) developing effective communication and information-sharing strategies (situational awareness) for public-health decision support, and 5) developing methods and evaluations for meeting workforce needs. Five working groups were formed to consider the above areas and to devise sample research questions that were refined further by the entire group of participants.     

Understanding Surge Capacity: Essential Elements

As economic forces have reduced immediately available resources, the need to surge to meet patient care needs that exceed expectations has become an increasing challenge to the health care community. The potential patient care needs projected by pandemic influenza and bioterrorism catapulted medical surge to a critical capability in the list of national priorities, making it front-page news. Proposals to improve surge capacity are abundant; however, surge capacity is poorly defined and there is little evidence-based comprehensive planning. There are no validated measures of effectiveness to assess the efficacy of interventions. Before implementing programs and processes to manage surge capacity, it is imperative to validate assumptions and define the underlying components of surge. The functional components of health care and what is needed to rapidly increase capacity must be identified by all involved. Appropriate resources must be put into place to support planning factors. Using well-grounded scientific principles, the health care community can develop comprehensive programs to prioritize activities and link the necessary resources. Building seamless surge capacity will minimize loss and optimize outcomes regardless of the degree to which patient care needs exceed capability.     

Developing Models for Patient Flow and Daily Surge Capacity Research

Between 1993 and 2003, visits to U.S. emergency departments (EDs) increased by 26%, to a total of 114 million visits annually. At the same time, the number of U.S. EDs decreased by more than 400, and almost 200,000 inpatient hospital beds were taken out of service. In this context, the adequacy of daily surge capacity within the system is clearly an important issue. However, the research agenda on surge capacity thus far has focused primarily on large-scale disasters, such as pandemic influenza or a serious bioterrorism event. The concept of daily surge capacity and its relationship to the broader research agenda on patient flow is a relatively new area of investigation. In this article, the authors begin by describing the overlap between the research agendas on daily surge capacity and patient flow. Next, they propose two models that have potential applications for both daily surge capacity and hospitalwide patient-flow research. Finally, they identify potential research questions that are based on applications of the proposed research models.     

State of Research in High-consequence Hospital Surge Capacity

High‐consequence surge research involves a systems approach that includes elements such as healthcare facilities, out‐of‐hospital systems, mortuary services, public health, and sheltering. This article focuses on one aspect of this research, hospital surge capacity, and discusses a definition for such capacity, its components, and future considerations. While conceptual definitions of surge capacity exist, evidence‐based practical guidelines for hospitals require enhancement. The Health Resources and Services Administration's (HRSA) definition and benchmarks are extrapolated from those of other countries and rely mainly on trauma data. The most significant part of the HRSA target, the need to care for 500 victims stricken with an infectious disease per one million population in 24 hours, was not developed using a biological model. If HRSA's recommendation is applied to a sample metropolitan area such as Orange County, California, this translates to a goal of expanding hospital capacity by 20%–25% in the first 24 hours. Literature supporting this target is largely consensus based or anecdotal. There are no current objective measures defining hospital surge capacity. The literature identifying the components of surge capacity is fairly consistent and lists them as personnel, supplies and equipment, facilities, and a management system. Studies identifying strategies for hospitals to enhance these components and estimates of how long it will take are lacking. One system for augmenting hospital staff, the Emergency System for Advance Registration of Volunteer Health Professionals, is a consensus‐derived plan that has never been tested. Future challenges include developing strategies to handle the two different types of high‐consequence surge events: 1) a focal, time‐limited event (such as an earthquake) where outside resources exist and can be mobilized to assist those in need and 2) a widespread, prolonged event (such as pandemic influenza) where all resources will be in use and rationing or triage is needed.     

Equipment,Supplies, and Pharmaceuticals: How Much Might It Cost to Achieve Basic Surge Capacity?

The ability to deliver optimal medical care in the setting of a disaster event, regardless of its cause, will in large part be contingent on an immediately available supply of key medical equipment, supplies, and pharmaceuticals. Although the Department of Health and Human Services Strategic National Stockpile program makes these available through its 12-hour "push packs" and vendor-managed inventory, every local community should be funded to create a local cache for these items. This report explores the funding requirements for this suggested approach. Furthermore, the response to a surge in demand for care will be contingent on keeping available staff close to the hospitals for a sustained period. A proposal for accomplishing this, with associated costs, is discussed as well.     

The Measurement of Daily Surge and Its Relevance to Disaster Preparedness

This article reviews what is known about daily emergency department (ED) surge and ED surge capacity and illustrates its potential relevance during a catastrophic event. Daily ED surge is a sudden increase in the demand for ED services. There is no well-accepted, objective measure of daily ED surge. The authors propose that daily and catastrophic ED surge can be measured by the magnitude of the surge, as well as by the nature and severity of the illnesses and injuries that patients present with during the surge. The magnitude of an ED surge can be measured by the patient arrival rate per hour. The nature and severity of the surge can be measured by the type (e.g., trauma vs. infection vs. biohazard) and acuity (e.g., triage level) of the surge. Surge capacity is defined as the extent to which a system can respond to a rapid and sizeable increase in the demand for resources. ED surge capacity includes multiple dimensions, such as systems, space, staffing, and supplies. A multidimensional measure is needed that reflects both the core components and their relative contribution to ED surge capacity. Although many types of factors may influence ED surge capacity, relatively little formal research has been conducted in this area. A better understanding of daily ED surge capacity and influencing factors will improve our ability to simulate the potential impact that different types of catastrophic events may have on the surge capacity of hospital EDs nationwide.     

Characteristics of Medical Surge Capacity Demand for Sudden-impact Disasters

Objectives
To describe the characteristics of the demand for medical care during sudden-impact disasters, focusing on local U.S. communities and the initial phases of sudden-impact disasters.
Methods
Established databases and published reports were used as data sources. Data were obtained to describe the baseline capacity of the U.S. medical system. Information for the initial phases of a sudden-impact disaster was sought to allow for characterization of the length of time before a U.S. community can expect arrival of outside assistance, the expected types of medical surge demands, the expected time for the peak in medical-care demand, and the expected health system access points.
Results
The earliest that outside assistance arrived for a community subject to a sudden-impact disaster was 24 hours, with a range from 24 to 96 hours. After sudden-impact disasters, 84% to 90% of health care demand was for conditions that were managed on an ambulatory basis. Emergency departments (EDs) were the access point for care, with peak demand time occurring within 24 hours. The U.S. emergency care system was functioning at relatively full capacity on the basis of data collected for the study that showed that annually, 90% of EDs were boarding admitted inpatients, and 75% were diverting ambulances.
Conclusions
As part of planning for sudden-impact disasters, communities should be expected to sustain medical services for 24 hours, and up to 96, before arrival of external resources. For effective medical surge-capacity response during sudden-impact disasters, there should be a priority for emergency medical care with a focus on ambulatory injuries and illnesses.     

Improving Surge Capacity for Biothreats: Experience from Taiwan

This article discusses Taiwan's experience in managing surge needs based on recent events, including the 1999 earthquake, severe acute respiratory syndrome in 2003, airliner crashes in 1998 and 2001, and yearly typhoons and floods. Management techniques are compared and contrasted with U.S. approaches. The authors discuss Taiwan's practices of sending doctors to the scene of an event and immediately recalling off-duty hospital personnel, managing volunteers, designating specialty hospitals, and use of incident management systems. The key differences in bioevents, including the mathematical myths regarding individual versus population care, division of stockpiles, the Maginot line, and multi-jurisdictional responses, are highlighted. Several recent initiatives aimed at mitigating biothreats have begun in Taiwan, but their efficacy has not yet been tested. These include the integration of the emergency medical services and health-facility medical systems with other response systems; the use of the hospital emergency incident command system; crisis risk-communications approaches; and the use of practical, hands-on training programs. Other countries may gain valuable insights for mitigating and managing biothreats by studying Taiwan's experiences in augmenting surge capacity.     

A Single Ventilator for Multiple Simulated Patients to Meet Disaster Surge

Objectives
To determine if a ventilator available in an emergency department could quickly be modified to provide ventilation for four adults simultaneously.
Methods
Using lung simulators, readily available plastic tubing, and ventilators (840 Series Ventilator; Puritan-Bennett), human lung simulators were added in parallel until the ventilator was ventilating the equivalent of four adults. Data collected included peak pressure, positive end-expiratory pressure, total tidal volume, and total minute ventilation. Any obvious asymmetry in the delivery of gas to the lung simulators was also documented. The ventilator was run for almost 12 consecutive hours (5.5 hours of pressure control and more than six hours of volume control).
Results
Using readily available plastic tubing set up to minimize dead space volume, the four lung simulators were easily ventilated for 12 hours using one ventilator. In pressure control (set at 25 mm H₂O), the mean tidal volume was 1,884 mL (approximately 471 mL/lung simulator) with an average minute ventilation of 30.2 L/min (or 7.5 L/min/lung simulator). In volume control (set at 2 L), the mean peak pressure was 28 cm H₂O and the minute ventilation was 32.5 L/min total (8.1 L/min/lung simulator).
Conclusions
A single ventilator may be quickly modified to ventilate four simulated adults for a limited time. The volumes delivered in this simulation should be able to sustain four 70-kg individuals. While further study is necessary, this pilot study suggests significant potential for the expanded use of a single ventilator during cases of disaster surge involving multiple casualties with respiratory failure.     

The Science of Surge: Detection and Situational Awareness

As part of the broader "science of surge" consensus initiative sponsored by Academic Emergency Medicine , this report addresses the issues of detection and situational awareness as they relate to surge in the practice of emergency medicine. The purpose of this report, and the breakout group that contributed to its content, was to provide emergency physicians and other stakeholders in the emergency medicine community a sense of direction as they plan, prepare for, and respond to surge in their practice.     

Advanced Statistics: Developing a Formal Model of Emergency Department Census and Defining Operational Efficiency

Background: Emergency department (ED) crowding has been a frequent topic of investigation, but it is a concept without an objective definition. This has limited the scope of research and progress toward the development of consistent and meaningful operational responses.
Objectives: To develop a straightforward model of ED census that incorporates concepts of ED crowding, daily patient surge, throughput time, and operational efficiency.
Methods: Using 2005–2006 patient encounter data at a Level 1 urban trauma center, a set of three stylized facts describing daily patterns of ED census was observed. These facts guided the development of a formal, mathematical model of ED census. Using this model, a metric of ED operational efficiency and a forecast of ED census were developed.
Results: The three stylized facts of daily ED census were 1) ED census is cyclical, 2) ED census exhibits an input-output relationship, and 3) unexpected shocks have long-lasting effects. These were represented by a three-equation system. This system was solved for the following expression, Censust = A(·) + B(·) cos(vT +ε) + a(et), that captured the time path of ED census. Using nonlinear estimation, the parameters of this expression were estimated and a forecasting tool was developed.
Conclusions: The basic pattern of ED census can be represented by a straightforward expression. This expression can be quickly adapted to a variety of inquiries regarding ED crowding, daily surge, and operational efficiency.     

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

Background

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

Study Objectives

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

Methods

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

Results

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

Conclusion

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

Surge Capacity Associated with Restrictions on Nonurgent Hospital Utilization and Expected Admissions during an Influenza Pandemic: Lessons from the Toronto Severe Acute Respiratory Syndrome Outbreak

Background Current influenza pandemic models predict a surge in influenza‐related hospitalizations in affected jurisdictions. One proposed strategy to increase hospital surge capacity is to restrict elective hospitalizations, yet the degree to which this measure would meet the anticipated is unknown. Objectives To compare the reduction in hospitalizations resulting from widespread nonurgent hospital admission restrictions during the Toronto severe acute respiratory syndrome (SARS) outbreak with the expected increase in admissions resulting from an influenza pandemic in Toronto. Methods The authors compared the expected influenza‐related hospitalizations in the first eight weeks of a mild, moderate, or severe pandemic with the actual reduction in the number of hospital admissions in Toronto, Ontario, during the first eight weeks of the SARS‐related restrictions. Results Influenza modeling for Toronto predicts that there will be 4,819, 8,032, or 11,245 influenza‐related admissions in the first eight weeks of a mild, moderate, or severe pandemic, respectively. In the first eight weeks of SARS‐related hospital admission restrictions, there were 3,654 fewer hospitalizations than expected in Toronto, representing a modest 12% decrease in the overall admission rate (a reduction of 1.40 admissions per 1,000 population). Therefore, influenza‐related admissions could exceed the reduction in admissions resulting from restricted hospital utilization by 1,165 to 7,591 patient admissions, depending on pandemic severity, which corresponds to an excess of 0.44 to 2.91 influenza‐related admissions per 1,000 population per eight weeks, and an increase of 4% to 25% in the overall number of admissions, when compared with nonpandemic conditions. Conclusions Pandemic modeling for Toronto suggests that influenza‐related admissions would exceed the reduction in hospitalizations seen during SARS‐related nonurgent hospital admission restrictions, even in a mild pandemic. Sufficient surge capacity in a pandemic will likely require the implementation of other measures, including possibly stricter implementation of hospital utilization restrictions.     

Australian private emergency departments can assist ambulance services by taking public emergency patients during surge and disasters

We describe a novel ambulance diversion programme, piloted in Victoria. This article discusses creating increased emergency capacity during surge or disasters by utilising private EDs, tested during a recent thunderstorm asthma disaster and an influenza epidemic. Public hospitals and EDs often run at or over capacity during normal operations. This leaves limited ability to manage surges in demand, resulting in suboptimal outcomes for patients, public ED staff and ambulance services. It is feasible to create surge capacity in private EDs for public ambulance patients. Other states could consider this option to help manage health disasters.     

Nursing Chronotherapeutics: A Conceptual Framework

Nurses frequently make decisions about when treatments and actions are performed. The nursing concern driving this review is the timing of nursing activities to optimize desired and minimize untoward effects. A nursing conceptual framework is proposed that highlights individual andenvironmental factors, as they relate to rhythmic responses, as well as places within the framework for nursing actions based on customary and usual temporal patterns.     

The Art and Science of Surge: Experience from Israel and the U.S. Military

In a disaster or mass casualty incident, health care resources may be exceeded and systems may be challenged by unusual requirements. These resources may include pharmaceuticals, supplies, and equipment as well as certain types of academic and administrative expertise. New agencies and decision makers may need to work together in an unfamiliar environment. Furthermore, large numbers of casualties needing treatment, newer therapies required to care for these casualties, and increased workforce and space available for these casualties all contribute to what is often referred to as "surge." Surge capacity in emergency care can be described in technical, scientific terms that are measured by numbers and benchmarks (e.g., beds, patients, and medications) or can take on a more conceptual and abstract form (e.g., decisions, authority, and responsibility). The former may be referred to as the "science" of surge, whereas the latter, an equal if not more important component of surge systems that is more conceptual and abstract, can be considered the "art" of surge. The experiences from Israel and the U.S. military may serve to educate colleagues who may be required to respond or react to an event that taxes the current health care system. This report presents concrete examples of surge capacity strategies used by both Israel and the U.S. military and provides solutions that may be applied to other health care systems when faced with similar situations.     

Surge Capacity for Health Care Systems: Early Detection, Methodologies, and Process

Excessive demand on hospital services from large‐scale emergencies is something that every emergency department health care provider and hospital administrator knows could happen at any time. Nowhere in this country have we recently faced a disaster of the magnitude of concern we now face involving agents of mass destruction or social disruption, especially those in the area of infectious diseases and radiological materials. The war on terrorism is not a conventional war, and terrorists may use any means of convenience to carry out their objectives in an unpredictable time line. Have we adequately prepared for the potentially excessive surge in demand for medical services that a large‐scale event could bring to our medical care system? Are our emergency departments ready for such events? Surveillance systems, such as BioWatch, BioSense, the National Biosurveillance Integration System, and the countermeasure program BioShield, offer hope that we will be able to meet these new challenges.     

Population-based Triage Management in Response to Surge-capacity Requirements during a Large-scale Bioevent Disaster

Both the naturally occurring and deliberate release of a biological agent in a population can bring catastrophic consequences. Although these bioevents have similarities with other disasters, there also are major differences, especially in the approach to triage management of surge capacity resources. Conventional mass-casualty events use uniform methods for triage on the basis of severity of presentation and do not consider exposure, duration, or infectiousness, thereby impeding control of transmission and delaying recognition of victims requiring immediate care. Bioevent triage management must be population based, with the goal of preventing secondary transmission, beginning at the point of contact, to control the epidemic outbreak. Whatever triage system is used, it must first recognize the requirements of those S usceptible but not exposed, those E xposed but not yet infectious, those I nfectious, those R emoved by death or recovery, and those protected by V accination or prophylactic medication ( SEIRV methodology). Everyone in the population falls into one of these five categories. This article addresses a population approach to SEIRV-based triage in which decision making falls under a two-phase system with specific measures of effectiveness to increase likelihood of medical success, epidemic control, and conservation of scarce resources.