A trauma system is an integrated collaboration of agencies and institutions organized to control the disease of injury. Its mission extends from effective prevention and public education to efficient societal reintegration of injury survivors. At the system’s core is coordinated and comprehensive care of acutely injured patients within a defined geographic area.^1,2,3 Its services are multidisciplinary, comprehensive, and encompass a continuum that includes all phases of patient need.^2,3,4,5,6

Trauma System Goals

Because geographical coverage exceeds that of a single hospital or health system, trauma systems provide seamless regionalization of resources to facilitate efficient use of available and qualified health care facilities within a defined geographic area. Cost efficient and efficacious coordination of resources is a defining characteristic of an effective trauma system. Disaster preparedness is also an important function of trauma systems. The institutions and agencies that form the trauma system are, by default, the platforms from where the regional response to care for victims of natural or manmade disasters are coordinated. The US Department of Health and Human Services has compiled a set of guidelines and standards for Model Trauma System Planning and Evaluation.⁷ This comprehensive document is an excellent source of information for every aspect of trauma system design and planning.

Transforming From Exclusive to Inclusive Trauma Systems

Elimination of preventable death by ensuring expeditious access to the resources of a designated trauma center is predicated on the recruitment of institutions committed to providing these resources. The need for triage of acutely injured patients at risk of death or disability to these centers resulted in development of field triage systems to identify those patients. Trauma systems thus evolved as networks of high capacity centers available for all injury victims, especially those at greatest risk. As understanding of what is required for efficacious population based management of the disease of injury has progressed, it has become clear that effective control of this disease requires participation of the entire community. To achieve optimal control of the disease of injury, systems that had developed for the exclusive care of the most severely injured required transformation to an inclusive regional enterprise that address all phases of injury control. This included effective integration and collaboration of designated trauma centers with all regional health care facilities. As American health care system shifts from reaction to patient disease to preemptive management of population wellness all trauma systems must be configured as inclusive.

The Nature of the Disease of Injury

The disease of injury affects all age groups with devastating personal, psychological, and economic consequences. Analysis of regional, national, age, and gender specific mortality for 240 causes of death comparing 1990 to 2013 clearly defines the primacy of injury as a global threat, especially to the young.⁸ There are huge discrepancies among nations and within various parts of the world. Many developed countries with resources to support trauma systems have experienced a decrease in trauma mortality, in contrast to less developed regions where injury remains a major killer, especially for those trapped in continuing civil strife. A recent report to Congress estimated that more than 50 million Americans sustained an injury requiring medical care in 2000, resulting in estimated lifetime costs of $406 billion; $80 billion for medical treatment and $326 billion for lost productivity.⁹

The modern approach to trauma care is based on lessons learned during war. Combat casualty care has been, and remains a major stimulus to the evolution of surgical care.¹⁰ Advances in rapid transport, volume resuscitation, management of complex injuries, surgical critical care, early nutritional therapy, deep venous thrombosis prophylaxis, and most recently, damage control resuscitation have all derived from wartime military experience.^11,12

History of Trauma System Development

The modern timeline of development of comprehensive trauma care began in 1949 when the American College of Surgeons Committee on the Treatment of Fractures, which had been established in 1922, was expanded to become the American College of Surgeons Committee on Trauma (ACSCOT). In 1961, a dedicated trauma unit was opened under the leadership of R. Adams Cowley, MD FACS, at the University of Maryland. The National Academy of Sciences and the National Research Council published Accidental Death and Disability: The Neglected Disease of Modern Society in 1966.¹³ This redefinition of injury as a preventable and treatable disease was a major stimulus to the development and propagation of systems of trauma care.

By 1973, Dr Cowley’s initiative engendered the Maryland Institute of Emergency Medicine, which became the first completely organized, statewide, regionalized trauma system. A similar initiative which included designation of trauma centers by state law was begun in 1971 in Illinois.¹⁴ Virginia followed suit in 1981, and established a statewide trauma system based on volunteer participation and compliance with national standards as defined by the ACSCOT.

In 1973, the Emergency Medical Services Systems Act became law, providing guidelines and financial assistance for the development of regional EMS systems. State and local agencies instituted prehospital care systems to deliver patients to major hospitals where appropriate care could be provided. Prehospital provider programs were standardized, and training programs were established for paramedics and emergency medical technicians (EMTs).

The American College of Surgeons published the first edition of the Optimal Hospital Resources for the Care of the Seriously Injured in 1976, establishing a standard for comprehensive delivery of trauma care. This document was the first to define specific criteria for the categorization of hospitals as trauma centers. The document is periodically revised to reflect current thought, and is recognized nationally and internationally as the standard for hospitals aspiring to be trauma centers. The most recent 6th edition entitled Resources for Optimal Care of the Injured Patient: 2014 was published in 2014.⁴ In addition to establishing evidence based criteria for prehospital and trauma care personnel, the 6th edition emphasizes the importance of ongoing performance and quality improvement.

ACSCOT developed the Advanced Trauma Life Support (ATLS) course in 1980, motivated in part by the personal experience of a surgeon involved in the crash of his private airplane. His own experience and his observations of the care provided to members of his family made him realize that more education about resuscitation and care of the injured patient was critically needed. The resulting ATLS course has contributed to the uniformity of initial care, has developed a common language for all care providers, and has been successfully promulgated throughout the world.

In 1985, the National Research Council and the Institute of Medicine published Injury in America: A Continuing Health Care Problem. This document concluded that there had been little progress toward reducing the burden of injury despite considerable funding committed to develop trauma systems.¹⁵ It also recommended investment in epidemiological research and injury prevention. As a result the Centers for Disease Control and Prevention (CDC) was designated as the national research center, to coordinate efforts at the national level in injury control, injury prevention, and all other aspects of trauma care.

In 1987, the ACSCOT instituted the Verification/Consultation Program to provide resources for trauma center verification. More recently, the ACSCOT added additional focus on systems development with publication of Consultation for Trauma Systems to provide guidelines for trauma system evaluation and enhancement.¹⁶ Concomitant with these efforts, the American College of Emergency Physicians (ACEP) published Guidelines for Trauma Care Systems.¹⁷ This document also addressed the continuum of trauma care and identified essential criteria for trauma care systems.

In 1988, the National Highway Safety Administration (NTHSA) established the Statewide EMS Technical Assessment Program and the Development of the Trauma Systems Course, both important tools to assess the effectiveness of trauma system components as well as support for ongoing system development. NHTSA also developed standards for EMS quality assessment, including trauma care. These standards required that the trauma care system be fully integrated into the state’s EMS system and be supported by enabling legislation (Table 4-1). The trauma care component must include designated trauma centers, transfer and triage guidelines, trauma registries, and initiatives through public education and injury prevention. In 1990, the Trauma Systems Planning and Development Act created the Division of Trauma and EMS (DTEMS) within the Health Resources and Services Administration (HRSA) to improve EMS and trauma care. Unfortunately, the program was not funded between 1995 and 2000, as many states were in the process of developing trauma systems. Two initiatives from this legislation are noteworthy: (1) planning grants for statewide trauma system development were provided to states on a competitive basis and (2) the Model Trauma Care System Plan was published as a consensus document. The Model Trauma Care System Plan established an apolitical framework for measuring progress in trauma system development and set the standard for the promulgation of systems of trauma care. The program was again funded in fiscal year 2001 but lost funding in 2006. New legislation is currently under consideration by the 114th Congress. The newest document for trauma system planning uses the public health care model of assessment, policy development, and evaluation of outcomes. With appropriate federal funding, this approach should be very successful.⁷

Modern Challenges

The evolution of trauma systems reflects two very critical elements of modern health care. First is the obvious mandate to ensure that properly trained and experienced personnel with the right equipment are immediately available for every injured patient. Linked to this is the reality that this extensive and intensive investment in personnel and resources demands accountability defined in better outcomes, more cost effective, efficacious care, and good stewardship of expensive resources. The disease of injury is expensive to treat. Its impact in terms of ongoing chronic care costs and lost human productivity are enormous, and not completely measurable, especially when the factor of diminished quality of life for survivors and their families is considered.

The current transformation of the health care system in the United States is focused on increased patient coverage, improved quality of care, and lower cost. This is often defined in terms of the triple aims of better care, lower cost, and improved population health.¹⁸ From the perspective of trauma systems these goals demand careful and ongoing review of the overall performance and effectiveness of every component of the system. The critical factor that guides planning of a trauma system is the balance of injury risk versus total cost of disease control sustained by the specific population to be served. While the ideal concept might be a designated trauma center within 5 minutes of ground transport for every citizen, the cost of maintaining such a network and the dilution of skills in management of severe, multiorgan injury would increase societal cost with no guarantee of improved clinical outcomes. In fact, the likelihood of inexperience driving unnecessary or avoidable cost is significant. The converse is also problematic. Too few trauma centers will almost certainly lead to an increase in preventable mortality, especially if access requires long-distance transport. From a population-based perspective, trauma system performance must be measured in terms of efficacy in maintaining wellness (injury prevention), and efficiency in treatment of injury victims (outcome). The population of injury victims is skewed toward a majority with non–life-threatening injury for whom timely, appropriate care should produce optimal recovery and avoidance of unnecessary expense. To this is added a complex core of severely injured who demand multidisciplinary care from qualified providers whose experience can contribute to optimal outcome in a cost-effective manner. Thus, in the emerging, modern health care environment, an accountable trauma system must balance the competing mandates of immediate access to the care of qualified, experienced personnel in designated facilities against unnecessary cost to the entire population generated by inappropriate replication of expensive resources.¹⁹ In a statement released in February 2015, the ACS emphasized the importance of controlling allocation of trauma centers. It reiterated that designation of trauma centers based upon regional population need has been recognized as an essential component of trauma system design since the 1980s.²⁰ Nonetheless, few trauma systems are currently able to operationalize these concepts, especially when faced with real or potential challenges that stem from powerful health care institutions or providers.

Processes of Trauma System Development

The critical milestones necessary to support statewide EMS and trauma system development as initially defined by West et al are listed in Table 4-1. Attainment of these criteria is a stepwise progression that begins with definition of need.^1,4 Historically, this has been accomplished by reviewing the outcome of regional trauma cases with special focus on preventable deaths.^21,22 The first step is to establish legal authority for system development. This usually requires legislation at a state or local level that provides public agency authority. The legislation must authorize the agency to define criteria for participation, establish a trauma registry as a fundamental component for system quality assurance, and implement processes for verification and designation. The surgeon’s role in articulating need and in guidance of system planning is critical in both leadership and commitment to optimal care. Designation must include continuous reporting of objective metrics of accountability from designated centers. The other critical component of authorizing legislation is adequate appropriation of resources for ongoing system management, which must include periodic needs assessment, assurance of fiscal solvency, and continuous focus on clinical outcomes.

One of the most critical components to be assessed in the deployment of a trauma system is cost, both in implementation and in ongoing system maintenance (Table 4-2). While the major goal of an inclusive trauma system is complete control of the disease of injury along the entire spectrum of prevention to successful societal reintegration of injury victims, reality dictates that each component of this ideal system have an adequate financial base to support its mission. The ideal is that any injured patient obtains immediate access to an appropriately designated trauma center. Unfortunately the cost of the ideal must be balanced against what is financially sustainable. The determination of need for a trauma center must first reflect its contribution to the overall capability of the trauma system to manage the disease of injury in the population being served. Part of this assessment must include overall taxpayer cost. As previously stated, too few trauma centers do not adequately serve the population, resulting in a more profound effect of injury on human productivity and longitudinal cost of care. Too many trauma centers produce unnecessary overhead to population health care costs, avoidable duplication of services, and potential dilution of provider skills in management of complex cases.²³ Trauma system funding parallels the challenges of providing coverage for individual patients. A “free-market” approach that would enable any hospital to establish a trauma service verified by an appropriate national organization would place the burden of financial viability on the business cycle of the hospital. National verification would assure that acceptable quality of care is widely available but the fiscal solvency of any trauma service would be sensitive to payer mix, resulting in financial stress to those facilities that serve unfunded patients. Subsidizing these hospitals with public funds to cover gaps in reimbursement adds an additional financial burden to all taxpayers, since a portion of all tax dollars already pays for the medical coverage of the uninsured. Because hospitals try to cover reimbursement deficits by raising prices, the overall cost of care for all citizens increases, thereby creating a triple taxpayer burden of additional cost for health care, and additional taxation to support care of those without adequate health insurance, and special subsidies to many of the institutions that are the default providers of care to these patients. The provision of comprehensive trauma care is a noble cause, but must be supported by a financial margin that does not undermine the fiscal solvency of the entire American health care system.

The most significant improvement in the care of injured patients in the United States has occurred through the development of trauma systems.^{24,25,26,27,28} However, recent data show that only 60% of states in the United States have statewide trauma systems, and about 20% have no trauma system at all. The necessary elements of a trauma system are access to care, prehospital care, hospital care, rehabilitation, prevention, disaster medical planning, patient education, research, and accountable financial planning. Prehospital communications, transport system, trained personnel, and qualified trauma care personnel for all phases of care are essential for a system’s success (Fig. 4-1).

External peer review generally is used to verify specific hospital’s capabilities and its ability to deliver the appropriate level of care. The verification process can be accomplished through the ACSCOT or by inviting experts in the field of trauma as outside reviewers. Quality assessment and quality improvement is a vital component of the system, as it provides directions for improvement as well as constant evaluation of the system’s performance and needs.^29,30,31,32

The Model Trauma Care System Plan introduced the concept of the “inclusive system” (Fig. 4-2). Based on this model, trauma centers are identified by their ability to provide definitive care to the most critically injured, and the trauma system assessed by its ability to manage all injuries.^33,34,35 Approximately 15% of all trauma patients will benefit from the resources of a level I or II trauma center. Therefore, it is appropriate to plan and expect an inclusive system to encourage participation and to enhance capabilities of the smaller hospitals. Surgical leadership is of fundamental importance in the development of trauma systems. Trauma systems cannot develop without the commitment of the surgeons of a hospital or community.

Public Information, Education, and Injury Prevention

Death following trauma occurs in a trimodel distribution defined in minutes, hours, and days after injury. Effective trauma programs must also focus on injury prevention, since more than half of the deaths occur within minutes of injury, and will never be addressed by acute care. Because trauma is not considered an important public health problem by the general population, efforts to increase awareness of the public as well as to instruct the public about how the system operates and how to access the system are important and mandatory. A recent Harris Poll conducted by the ATS showed that most citizens value existence of a trauma system with the same importance as fire and police services. Continuous epidemiological surveillance to define interventions that will likely reduce both injury occurrence and severity requires trauma systems to focus on injury prevention. Identification of risk factors and high-risk groups, development of strategies to alter personal behavior through education or legislation, and other preventive measures have the greatest impact on trauma in the community, and, over time, will have the greatest effect on all trauma victims.^18,19,20

Human Resources

Because the system cannot function optimally without qualified personnel, a high quality system provides comprehensive and continuing education to its providers. This includes all personnel along the trauma care continuum: physicians, nurses, EMTs, and others who impact the patient and/or the patient’s family.

Prehospital

Trauma care prior to hospital arrival has a direct effect on survival. The system must ensure prompt access and dispatch of qualified personnel, appropriate care at the scene, and safe and rapid transport of the patient to the closest, most appropriate facility. The primary focus is on education of paramedical personnel to provide initial resuscitation, triage, and treatment of trauma patients. Effective prehospital care requires coordination between various public safety agencies and hospitals to maximize efficiency, minimize duplication of services, and provide care at a reasonable cost. There are many comprehensive and standardized courses covering virtually every aspect of prehospital care. Most are the products of national and international organizations dedicated to emergency medical care, and should be considered as the preferred alternative to “home grown” courses or periodic symposia that provide inconsistent educational impact.

Communications System

A reliable communications system is essential for providing optimal trauma care. Although many urban centers have used modern electronic technology to establish emergency systems, most rural communities have not. A communications system must include universal access to emergency telephone numbers (eg, 911), trained dispatch personnel who can efficiently match EMS expertise with the patient’s needs, and the capability of EMS personnel at the trauma incident to communicate with prehospital dispatch, the trauma hospital, and other units. Access also requires that all users know how to access and actually use the system. This can be achieved through public safety information and school educational programs designed to inform health care providers and the public about emergency medical access.

Medical Direction

Medical direction provides the operational matrix for care provided in the field. It grants freedom of action and limitations to EMTs who must rescue injured patients. The medical director is responsible for the design and implementation of field treatment guidelines, their timely revision, and their quality control. Medical direction can be “off-line” in the form of protocols for training, triage, treatment, transport, and technical skill operations or “online,” given directly to the field provider.

Definitive Care Facilities

Acute care hospitals are the foundation of the regional trauma system. An inclusive trauma system integrates acute care facilities of all levels to provide the full spectrum of injury care within its region. Central to trauma system planning is the designation of definitive trauma care facilities to meet community need. The number and levels of trauma centers should match the population distribution in the region. Trauma centers concentrate rare and high value resources required to optimize care of the injured patient. Concentration of injured patients in trauma centers enhances clinical experience and promotes expertise, education, and research. In principle, the designating authority is responsible for determining the number and level of trauma centers needed to provide optimal care in its region. In practice, trauma centers and acute care hospitals should coexist within a region and cooperate to ensure appropriate distribution of patients based on resource needs, contribute data to trauma system registries, and participate in system performance improvement. A trauma center is an acute care hospital that organizes its available resources around the care of the injured patient. This effort requires the commitment hospital administration and the medical staff to allocate human and material resources and develop performance improvement programs to optimize care of the injured patient. Common to all trauma centers is the trauma program lead by a trauma medical director and a trauma program manager, a trauma registry managed by trained registrars, a comprehensive trauma performance improvement system, and an effective patient safety program. The clinical capabilities and the depth and complexity of resources committed to the trauma program differentiate trauma centers into mission related levels.

Trauma Center Facilities and Leadership

Hospital care of the injured patient requires commitment from specific facilities to provide administrative support, medical staff, nursing staff, and other support personnel. The trauma center integrates into the trauma care system by providing local or regional leadership. Trauma centers are categorized by level, as described below.

Level IV Trauma Center

In principle the level IV center serves as an initial access point to the regional trauma system and usually serves rural communities. The level IV trauma center must have 24-hour emergency coverage and provide initial evaluation and stabilization of injured patients most of whom will be transferred for definitive treatment. Thus the level IV trauma center must have an organized trauma resuscitation team that follows standardized protocols and predefined transfer plans for patients needing a higher level of care.

Level III Trauma Center

The level III center is also an entry point to the regional trauma system usually in communities that are remote from major trauma centers. The presence of general surgery capability differentiates the level III from the level IV center and it is expected that a general surgeon will be present in the emergency department to lead the trauma resuscitation team upon arrival of the major trauma patient. The role of the level III center is to provide definitive care to the mild and moderately injured and initial stabilization for the major trauma patient, which may include operative hemorrhage control to ensure safe transfer to a major trauma center. As with the level IV center, predefined plans for transfer of patients to the major trauma centers are essential.

Level II Trauma Center

The level II provides definitive care to the injured patient, and functions in two distinct roles recognized by the ACS COT. The first is as a facility in a population dense area in which a level II center may supplement the clinical activity and expertise of the regional level I center. In this context, the level I and II centers cooperate to ensure optimal resource utilization. The second is in less populated areas distant from the regional level I center. In this context the level II center may serve as the lead hospital for its region and provide support to local minor trauma centers in the same service area. The level II centers include the specialty services needed to provide definitive care to the severely injured but the clinical capabilities may not be as comprehensive as the level I centers. Although the clinical capabilities are similar to LI, the level II centers may not treat a volume of severely injured patients similar to LI centers. Although graduate education and research are not required functions of level II trauma centers the mandate for similar clinical capabilities requires that LII centers provide effective access to continuing medical education (CME).

Level I Trauma Center

The level I trauma center is a regional resource and tertiary care facility capable of providing immediate definitive and comprehensive care to all injured patients regardless of severity or complexity. It is the cornerstone of the regional trauma system. In addition to comprehensive acute care responsibilities, the level I trauma center has a major responsibility for providing leadership in system planning, research, education, and training of trauma care providers. Level I trauma centers are generally located in large, population dense areas and are typically affiliated with university teaching hospitals. Colocation with a large population and a high volume of severely injured patients is necessary to provide sufficient experience to develop clinical expertise, train new providers, and fulfill the level I research and education missions.

The Trauma Resuscitation Team

In all trauma centers there must be a defined trauma resuscitation team consisting of predesignated personnel and specific assignments. The team’s main purpose is rapid patient assessment, provision of immediately lifesaving interventions, initiation of comprehensive resuscitation, expeditious diagnostic workup, and provision of definitive care. Critical to the resuscitation team’s function is linkage to EMS and timely prehospital notification. For major trauma patients identified in the field, the resuscitation team must be preassembled and immediately available upon patient arrival. The constituents, role, and capabilities of the resuscitation team depend on the level of trauma centers.

Specialty Trauma Centers

Regional specialty facilities concentrate expertise in a specific discipline and serve as a valuable resource for patients with critical specialty-oriented injuries. Examples include replantation, pediatric trauma, bums, spinal cord injuries, and hand trauma. Where present, these facilities provide a valuable resource to the community and should be included in the design of the system. Most importantly, the unique capabilities of each must be seamlessly woven into the process of care so that the required specialty care is available at the appropriate time in the continuum of management of the patient. A pediatric trauma center is expected to have the same resuscitative capabilities as any center receiving acutely injured patients from the field. A replantation or burn center, on the other hand, is usually reliant on comprehensive initial evaluation of the patient by a referring center with whom it must have established transfer guidelines and protocols.

Acute Care Facilities Within the Trauma System

Many general hospitals exist within a trauma care system but are not officially designated as trauma centers. Circumstances often exist in which less severely injured patients reach these hospitals and appropriate care is provided. The trauma system should develop and manage protocols for inter facility transfer of patients whenever a major trauma patient is inappropriately triaged to an undesignated facility. Moreover, the trauma system’s registry must be able to identify and track these injured patients managed at non designated facilities.

All acute care facilities play important roles in the regional trauma system. Most patients have minor injuries and can receive effective and definitive care in acute care hospitals (Fig 4-3). Community hospitals and minor trauma are critical to the care of mild and moderately injured by providing effective treatment to patients in their home communities. This helps minimize the burden on the patient and preserves major trauma center resources for the care of the more seriously injured. However, major trauma centers, especially level I centers are typically large tertiary referral centers located in population dense areas and serve as the primary hospital for their communities. As such, major trauma centers tend to attract a many mild and moderately injured patients simply because of proximity to the population and large market share.³⁵ Effective trauma system planning must recognize this phenomenon to ensure the proper balance of trauma center numbers and levels within a region. Sufficient minor trauma resources should be available to care for the minor and moderately injured and sufficient major trauma center resources to not only ensure access to definitive care for the severely injured, but also concentrate severe injury volume in a limited number of major trauma centers to optimize clinical competency through experience and maximize efficiency through conservation of scarce, high value human and material resources.

Rehabilitation

The disease of injury is described as a continuum of care that begins with failure of prevention and ends with complete societal reintegration of a recovered patient. In reality, injury is a disease that never really ends. The issues of long-term neurocognitive dysfunction and early onset of degenerative disorders is well defined in current literature. Less well understood are the impacts of chronic musculoskeletal disorders, chronic pain affliction, and numerous other impairments that undermine quality of daily living and social function. Rehabilitation is as important as prehospital and acute hospital care. Early and aggressive rehabilitation has been shown both to accelerate and enhance recovery, yet it is often least considered and incompletely available. Many insurance policies do not even cover rehabilitation, leading to a major additional burden for the “insured” patient who discovers that coverage ends with hospital discharge. Although it is critically important to reintegrating the patient into society, only 1 of 10 trauma patients in the United States has access to an adequate rehabilitation program. Rehabilitation is often the longest and most difficult phase of care for both patient and family. It can be provided in a designated area within the trauma center or by agreement with a freestanding rehabilitation center, but it must be provided! While it is not the purpose of this chapter to address all of the deficiencies of the health care system, it is important that trauma system planners understand this deficiency and establish processes that provide immediate involvement of rehabilitation experts as well as case managers to optimize timing and effect of patient rehabilitation, and, from the other side of the coin, limit unnecessary acute care hospitalization necessary because of lack of rehabilitation access. This latter phenomenon is detrimental to optimal recovery, adds additional financial burden to the trauma center, and denies acute care beds to other injury victims.

Emergency Response and Trauma System Access

A critical function of the regional trauma system is to ensure that all injured patients within its geographic boundaries have access to definitive care to meet their injury needs. Access to the trauma system is dependent on the availability of prehospital transport services, the proximity and availability of definitive care resources, and the processes that direct the injured patient to definitive care. Ideally, the geographic distribution of trauma centers matches the population distribution and prehospital resources are organized such that timely access to the trauma center is ensured independent of distance. In 2005, it was estimated that 69.2% of US residents could access a major trauma center within 45 minutes and 84.1% could access one within 60 minutes of injury.³⁶ The remainder lived primarily in rural areas and states with the most urban populations had the highest proportions that could access a trauma center within an hour. More current data estimates that 63.1% of the US population can reach a major trauma center within an hour by ambulance and the inclusion of helicopter services increased this proportion to 90.4%. The University of Pennsylvania, in consort with the American Trauma Society and with support of the US Department of Health and Human Services manages a comprehensive website (http://www.TraumaMaps.org) which is periodically updated and provides a continuous overview of trauma system coverage in the United States.