Key points

The influence of military experience on the evolution of modern trauma systems of care

The established paradigms and future directions in the systems of care for patients with neurotrauma have been dependent on the evolution of care for injured patients in general. The path of a patient with trauma occurs along a continuum from prehospital care and transport to postacute services and community reintegration ( Fig. 1 ). The clinical science and logistical organization that occurs within this continuum has advanced rapidly since the late 1800s. Developments during armed conflicts spurred advances, which have later been applied to civilian trauma. The advances extend beyond clinical innovations garnered secondary to the experience of treating patients with unique wounds. Learned lessons include optimized logistics during the initial transport and field stabilization of individual patients to the organization of complex systems of care containing highly specialized components. The successful incorporation of these practices into the care of civilian patients with trauma was made possible through changes in the broader field of healthcare delivery, including the evolution of hospital-based emergency services in conjunction with the implementation of a number of legislative policies at the local, state, and national levels.

The path of an injured patient from time of injury to postacute care and community integration exists along a continuum of care. There are discrete decision points along this continuum that require coordination and integration. This holds true for all patients with trauma, including brain and spine injury.

( Reprinted with permission from Elsevier. The Lancet Neurology, December 2017, 16 (12), 987-1048.)

The field of trauma surgery evolved through several wars over the past 200 years. The Civil War, and specifically the Union Army, saw an improvement in case-fatality rates from 1861 to 1865 secondary to a number of factors including the dissemination of best practice materials in the care of patients with battlefield injury, notably Stephen Smith’s Handbook of Surgical Operations published in 1863. In the course of World War I, advances were made in the transport of patients from the battlefield through tiered stations and facilities, each with increasing resources and capabilities, a paradigm that became the basis for today’s trauma systems. In World War II the components of triage and resuscitation were importantly applied to patient evacuation. In the Korean and Vietnam wars, the model of tiered evacuation changed to that of transport of severely injured patients to facilities capable of definitive care, which was made possible by helicopters. The late twentieth and early twenty-first centuries experienced The Gulf War and Operation Enduring Freedom, respectively, which brought about a number of advancements from the clinical concepts of damage control surgery to battlefield-based research and expanded quality improvement efforts.

These innovations from military medicine, combined with related policy developments, drove the continued evolution of modern trauma centers.

The influence of policy on modern trauma systems of care

The nascent consolidation of specialized services into trauma units and centers occurred in the 1960s. There was an increasing awareness of the burden of unnecessary mortality in patients with traumatic injuries. In 1961, Dr R Adams Cowley opened the first trauma unit at the University of Maryland, followed by Chicago’s Cook County Hospital in 1966, and San Francisco General Hospital in 1969. Concurrently in 1966, the National Research Council through the National Academy of Sciences published the white paper entitled, Accidental Death and Disability: The neglected disease of modern society . This document spurred further development of trauma systems as it extensively detailed national gaps and needs within this realm, while outlining key recommendations. Areas of priority included increasing research funding, creating data registries to facilitate the evaluation of outcomes, and establishing a medical specialty dedicated to emergency care. The development of formal trauma systems was further potentiated by the availability of funds conferred through the Emergency Medical Services Act of 1973. These factors essentially served as the inception of emergency care as we know it today.

In 1976, the American College of Surgeons Committee on Trauma, published The Optimal Hospital Resources for Care of the Seriously Injured , now termed the Resources for Optimal Care of the Injured Patient. The report delineated the evaluation and designation of trauma centers according to resources and capabilities and served as the basis for modern trauma center classification. In the 1980s, the American College of Surgeons (ASC) Committee on Trauma (COT) started its official verification process accounting for trauma volume, resource availability, and presence of subspecialty expertise. The intention of this verification was to exceed those requirements for designation, which occurs on the regional and state levels.

In the late twentieth and early twenty-first centuries, several other studies, policies, reports, and legislation contributed to the proliferation of trauma centers and systems. Although it ended 5 years after its inception, The Trauma Care Systems Planning and Development Act, enacted in 1990, facilitated the expansion of trauma systems nationally. In 1992, Health Services and Resource Administration developed the Model Trauma Care Systems Plan emphasizing the need for inclusive trauma care system, which evolved in 2006 to a framework that approached trauma as a public health disease with a complex integration of various functions ( Fig. 2 ). These efforts ultimately culminated in calls for a national trauma system as described in the National Academies of Science, Engineering, and Medicine report.

Successful trauma systems of care require integration of several public health components from research, policies, appropriate governance, and community interfacing.

( From Model Trauma System Planning and Evaluation. In: Services USDoHaH, ed.: Health Resource Service Administration; 2006.)

Current work in neurotrauma systems of care

As learned from the military, to deliver optimal trauma care along the continuum of injury, trauma centers work best as a part of a system. Although these concepts have been well established in the care of patients with general trauma, the application to neurotrauma is in its infancy, and there are a limited number of well-conducted studies evaluating the benefits to patients with neurotrauma.

However, the field of neurotrauma has made significant advancements regarding the cohesion of scientific study with attempts at the standardization of clinical care. There have been various efforts in data collection and integration with care delivery. There are a number of important research collaboratives and consortiums from which research has inevitably evolved. The gains in these research partnerships are perhaps the most robust components of the established systems of care in neurotrauma.

The United States Department of Health and Human Services National Institute on Disability, Independent Living, and Rehabilitation Research has 2 national funding endeavors with the goal of formulating knowledge to improve the multidisciplinary care specifically with regard to rehabilitation of patients with traumatic brain injury and traumatic spinal cord injury. One of the main goals is to standardized data collection across multiple sites that comprise institutional leaders in the field. Each respective site contributes deidentified patient data to a national database while both conducting primary site and collaborative studies. The endeavor pertaining to traumatic brain injury is the Traumatic Brain Injury Model System (TBIMS), which consists of 16 centers across the United States and has been in inception since 1988. The corollary for spinal cord injury, the Spinal Cord Injury Model System was conceived in 1973 and currently consists of 18 centers across the country.

A clinical extension of this component of care delivery exists within the Veteran Affairs Polytrauma/Traumatic Brain Injury System of Care, a tiered network of centers from regional referral centers (Polytrauma Rehabilitation Centers) down to local Polytrauma Support Clinic Teams. This paradigm allows for the delivery of specialized rehabilitation and coordination services across the country. ^, In addition to the clinical services provided, the collaborative research mechanisms were established in 2010 through a strategic partnership with the TBIMS.

There are several important research collaboratives that exist outside of rehabilitation. The exhaustive discussion of all efforts is beyond the scope of this study but demonstrate the expansive work in this regard. The Transforming Research and Clinical Knowledge in TBI (TRACK-TBI) Study funded by the National Institute of Neurological Disorders and Stroke consisted of a multi-institutional effort composed of 18 Level-1 Trauma Centers across the United States that collected detailed observational and longitudinal data on 3000 individuals with traumatic brain injury. This eventually evolved into the TRACK-TBI Network, a phase 2 TBI clinical trial network. Although this review focuses on efforts within the United States, it is important to mention the European counterpart to TRACK-TBI, named Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (Center-TBI) – a prospective, longitudinal effort consisting of 68 centers across 20 countries as well as the Canadian Traumatic Brain Injury Consortium.

With regard to clinical guidelines, similarly a number of efforts have been advanced. The Brain Trauma Foundation (BTF) was founded in 1986 as an effort to further research in TBI. Since its inception, the BTF has produced a number of guidelines addressing points along the continuum of care. For example, the severe traumatic brain injury guidelines (the fourth edition of which was published in 2016) and prehospital guidelines (published in 2023) attempt to provide consistency of clinical care.

Recently, the National Academies of Sciences, Engineering, and Medicine, similar in facilitating previous efforts, released a report in 2022 entitled Traumatic Brain Injury: A Roadmap for Accelerating Progress. The report conveyed significant gaps within the field, and a subsequent action collaborative was developed to address several of the recommendations outlined in this report. The most salient of these recommendations included the following: improve the quality and consistency of care, foster systems of care delivery on a geographic basis, and develop learning health systems by amalgamating research and clinical care. A new emphasis was the postacute component along the continuum of care in patients sustaining TBI with the focus on effective and well-established models of multidisciplinary postacute care.

The future: opportunities and challenges

Despite the previously mentioned efforts, there still exists significant regional, institutional, and surgeon-dependent variability in care delivery to the patient with neurotrauma. This affords opportunities and the potential to borrow from other fields and disciplines, especially trauma surgery.

The reason to this variability is multifactorial. Traumatic brain and spinal cord injury is an inherently heterogeneous and complex disease process. Currently utilized outcome and process measures such as rates of intracranial pressure monitoring and time until monitor placement may not be the most nuanced or encompassing to provide effective evaluation of care delivery. Further, the minimum standards to determine adequate neurosurgical coverage may need to be further refined as well. Thus, the goal should be to establish in-depth and comprehensive criteria specific to patients with neurotrauma during the designation process.

For this to occur effectively, in addition to delineating the most valuable clinical outcomes and process measures, there is a necessity to understand the basis to the observed differences in care. This includes determining key differences in the organizational components of various neurotrauma centers while aligning language and further building upon the sharing of scientific data described earlier.

Indeed, in the field of trauma surgery, there are efforts to do just this. One of these studies entitled Comparative Assessment Framework for Environments of Trauma Care seeks to develop the framework and electronic infrastructure to better acquire data and compare the differences in organizational structures among trauma institution through web-based tools.

The improved understanding of the logistical and organizational components of centers that provide exceptional neurotrauma care must be accompanied by the advancement of how care is delivered to these patients. This may appear as an evolution of a new specialty dedicated specifically to acute care neurosurgery from operative to nonoperative conditions. The paradigm for this evolution can be emulated in the relatively recent development of the field of acute care surgery.

Formally formed in 2005, acute care surgery was conceived to address the cultural, economic, and logistical forces leading to changes in the field encompassing trauma, emergency general surgery, and surgical critical care. The evolution of this specialty has demonstrable benefits including improved overall outcomes for acute care patients, and more expeditious care while simultaneously being financially favorable for hospitals. ^, To advance the systems and delivery of care pertaining to patients with neurotrauma, a similar effort to develop a field specific to neurosurgical emergencies may be explored especially given the above conveyed benefits.

Despite a number of opportunities and avenues to advance systems of care around patients with neurotrauma, there are a number of a challenges both within the field and larger forces. In the United States, there has been an increase in the number of trauma centers with the apparent goal of addressing demonstrable gaps in access. The benefits of formal trauma centers on a number of clinical outcomes in the civilian population have been studied since the 1970s. West and colleagues first demonstrated in 1979 the significant difference in preventable deaths between Orange County, CA, which lacked a trauma center and San Francisco, CA, with its established San Francisco General Hospital Trauma Center, as previously mentioned. A study by MacKenzie and colleagues in 2006 demonstrated a significantly lower in-hospital mortality when care was provided in a trauma center compared to not, and a study in 2007 by Newgard and colleagues reaffirmed lower in-hospital mortality when patients were transferred from nontertiary centers to major trauma centers. ^, In patients with traumatic brain injury specifically, there is a derived benefit of trauma centers providing the initial care compared to nontrauma centers with established neurosurgical capabilities. This is especially true for the elderly population. The opening of trauma centers in areas of need improves outcomes. Despite this, most of the institutional proliferation has occurred in areas that are already served by pre-existing centers.

Overall the vast majority of counties in the country have, not experienced an increase in access to either level I or level II trauma centers. The skewed proliferation of trauma centers can lead to several unintended consequences, including the reduction in patient volumes per center. There is a discernible and established relationship between trauma-center volume and in-hospital outcomes elucidated in the general trauma population. This association also holds true when evaluating the subgroup of a TBI populations.

The lack of expanding access as well as the diluting of patient volume may explain why the increase in the number of trauma centers has not contributed to an improvement in clinical outcomes. For example, there has not been a derived positive impact on trauma-related deaths. Although not directly correlated with volume, there is evidence that patients with severe traumatic brain injury have improved outcomes when obtaining surgical care at level I trauma centers. This is related as higher mortality and lower functional measures when patients undergo craniotomy or craniectomy in a level II compared to level I centers.

The evolution of trends in trauma center proliferation uncover a larger question as it pertains to the care of the patient with neurotrauma; how to identify institutions that have the resources, expertise, and capabilities to deliver the highest level of care with the best outcomes.

Furthermore, reimbursing healthcare services purely on a volume basis presents significant limitations when applied to trauma care. Unlike elective medical procedures, trauma volume is inherently unpredictable, and much of the cost in trauma centers arises from maintaining expensive resources and specialized staff in continuous readiness. Consequently, while a volume-based reimbursement model may effectively compensate elective medical care, ensuring adequate access for patients, it inadequately addresses the unique economic realities of trauma care. To illustrate, fire departments are not funded by the number of fires extinguished, but by their readiness to respond at any moment. Similarly, trauma centers require reimbursement mechanisms that account for the essential but irregular demand for their services, ensuring sustainability independent of case volume alone. There are many mechanisms in place that can be modified to do this, such as Medicaid directed payments, critical access hospital designation, or other federal/state granting mechanisms. Policymakers should consider realigning financial incentives in the area of trauma care.

The terminology used to categorize trauma centers and levels currently exists in 2 forms. Trauma center “designation” is assigned according to applicable criteria determined by individual state and local governments. There is thus expected variability in these criteria among states and regions. Trauma center “verification” conversely is a voluntary evaluation process by which American College of Surgeons evaluates whether an institution possesses the policies, personnel, and overall capabilities to meet the criteria set forth in the RESOURCES FOR THE OPTIMAL CARE OF THE INJURED PATIENT. While comprehensive in overall assessment, the current benchmarks may not provide optimum measures with which to evaluate the care of patients with neurotrauma in detail.

With regard to the difference in outcomes of verified versus designated centers, the present body of literature is limited by effective controls, although there may be evidence on the association with lower mortality in centers that receive formal ACS verification. The appropriate comparison is understandably confounded by state-to-state differences in designation, but still uncovers the current challenges for the best way to formally recognize the provision of appropriate care.

Summary

There has been the rapid evolution of trauma centers and systems of care over the past 200 years. The comprehensive and wholistic systems specific to patients with neurotrauma, however, are in their relative infancy when accounting for the entire continuum of patient course from preinjury prevention to longitudinal postacute care. Although there are a number of opportunities for development and growth, there are existing challenges within the field that must be overcome, especially ascertaining optimal process and outcomes measure to identify institutions best able to care for the patient with neurotrauma.