Trauma system development
R. A. Lendrum
The word ‘trauma’ describes the disease entity resulting from physical injury. Trauma is one of the leading causes of death worldwide and deaths due to injury look set to increase. As early as the 1970s, it became evident that centralisation of resources and expertise could reduce the mortality rate from serious injury and that organisation of trauma care delivery into formal systems could improve outcome further. Internationally, trauma systems have evolved in various forms, with widespread reports of mortality and functional outcome benefits when major trauma management is delivered in this way. The management of major trauma in England is currently undergoing significant change. The London Trauma System began operating in April 2010 and others throughout England became operational this year. Similar systems exist internationally and continue to be developed. Anaesthetists have been and continue to be involved with all levels of trauma care delivery, from the provision of pre-hospital trauma and retrieval teams, through to chronic pain management and rehabilitation of patients back into society. This review examines the international development of major trauma care delivery and the components of a modern trauma system.
Trauma – the scale of the problem
Worldwide, trauma constitutes a massive public health problem. Approximately 5.8 million people die annually as a result of injury, representing 10% of the world’s deaths. This figure is 32% more than the number of deaths from the major diseases of malaria, tuberculosis and HIV/AIDS combined. Nearly one third of these deaths result from violence and almost one quarter from road traffic collisions, with considerable geographical variation in the causes of death . Those who die as a result of trauma represent only a fraction of those injured. Every year, approximately 50 million people suffer moderate or severe disability, resulting in the loss of 180 million disability–adjusted life years . Although trauma affects people of all ages, it primarily affects the young. Injuries sustained as a result of road traffic collisions are the leading cause of death worldwide in the 15–29 year old age group. Therefore, as a disease, trauma places a significant socioeconomic burden on society. Unfortunately, the burden of disease resulting from injuries is set to increase substantially with the leading global causes of death from trauma – road traffic collisions, homicide and suicide – predicted to become the 5th, 12th and 18th leading causes of death, respectively, by 2030 . In the UK, estimates of the incidence of major trauma (defined as an Injury Severity Score (ISS) > 15) vary. There are approximately 20 000 cases of major trauma resulting in around 5400 deaths in England per year, plus many more victims left with permanent disabilities demanding long-term rehabilitation. It is estimated that there are a further 28 000 cases of trauma that do not fulfil the definition for major trauma, but require similar management .
The management of the consequences of trauma consumes a significant proportion of public funds worldwide. In England, it is estimated that the acute care of major trauma costs the NHS between £0.3 and £0.4 billion per year, with the cost of ongoing hospital care, rehabilitation and long-term care remaining unknown. Annual lost economic output resulting from major trauma is estimated to be between £3.3 and £3.7 billion . In the US in 2009, the total cost of unintentional injuries (economic and healthcare costs) was estimated to be $693.5 billion .
Trauma systems–evolution and evidence
The huge economic and societal burden that trauma exerts worldwide has driven significant developments in the infrastructure required to manage these patients effectively over the past 45 years . There has been improved understanding of the pathophysiology of trauma-related disease as well as progress in pre-hospital and emergency department (ED) care, imaging, trauma surgery and critical care that has improved major trauma survival. However, the effectiveness of treatment may be reduced if interventions are not available promptly . This principle has been pivotal in the international drive to develop formal trauma systems.
The evolution of modern trauma systems began during the US military deployments in Korea and Vietnam . Difficult terrain, the availability of helicopters and increasing experience of the benefits of rapid evacuation to definitive care resulted in mean transfer times dropping from 4 h in World War II, to 85 min in Korea and 27 min in Vietnam. Correspondingly, mortality dropped from 4.5% in World War II to 1.9% in Vietnam [7, 8]. Although many other factors such as better resourced forward hospitals and the availability of blood undoubtedly contributed to this drop in mortality, improved organisation of the delivery of trauma care, with rapid evacuation to a designated receiving hospital, was fundamental. The National Research Council and the US National Academy of Science published a report in 1966 titled Accidental Death and Disability – The Neglected Disease of Modern Society , that provided the stimulus for the development of civilian trauma systems. It clearly described the anomalous situation where the quality of civilian trauma care in the US was far inferior to that provided to deployed military personnel in Vietnam. In 1976, the American College of Surgeons established criteria for the designation of trauma centres and the construction of trauma systems, paving the way for the current systems in place in the US . The first civilian evidence of the potential benefits of trauma centre care came from a retrospective analysis of 100 consecutive road traffic collisions during 1974 in San Francisco (urban environment, patients taken to single trauma centre) and Orange County (rural environment, patients taken to nearest receiving facility), that examined preventable deaths. Approximately one third of the deaths related primarily to central nervous system (CNS) injury and two thirds of deaths not related to CNS injury in Orange County were considered preventable, with almost none of the deaths occurring at the trauma centre deemed so . Although this was a retrospective, subjective, panel review study, it provided the first indication that centralised and aggressive intervention by experienced personnel could potentially reduce the mortality rate resulting from injury. It also recognised that a single major trauma centre in Orange County, with a large, dispersed, rural population, would not be best served by a single major trauma centre and that an organised ‘system’ of trauma care would be required . Hypoxia, uncontrolled haemorrhage, missed injuries and delayed/absent surgical intervention were key causes of preventable death , which would go on to become common themes over the following years in the US, the UK and elsewhere . Six years later, a regionalised trauma system was established in Orange County and significant reductions in the preventable death rate were demonstrated . Further evidence from the US has reinforced the message that centralisation of services into major trauma centres and the development of trauma systems or networks for managing injured patients can significantly reduce the in-hospital mortality of major trauma [14–17]. This reduction in mortality rates was largely confined to those patients with more severe injuries (single Abbreviated Injury Score of ≥ 4) and maintained in the first year after discharge from hospital . It may also be the case that trauma system/trauma centre care can reduce long-term morbidity of survivors  and improve functional outcomes [19, 20]. The evidence of the ability of trauma centres and systems to reduce mortality after injury is largely based on population-based studies, classed as strong grade-3 evidence . However, there is still compelling evidence from the US that centralisation of resource and expertise as part of a managed clinical system for the provision of trauma care reduces mortality after serious injury by between 15% and 25% [16, 21, 22]. This improvement does not appear immediately after trauma system implementation and the mortality and morbidity benefits can continue to improve for more than 10 years . This gradual improvement in quality is likely to occur as pre-hospital and trauma triage protocols mature, inter-hospital transfer protocols evolve and the trauma centres themselves become more organised, experienced and better resourced . Trauma centre care within the envelope of a mature trauma system appears to be cost-effective , with evidence of a 5- to 15-fold return of investment for each patient returned to work . In terms of cost per life year saved, regionalised trauma centre care costs significantly less than the provision of renal dialysis, breast cancer treatment or the percutaneous or surgical management of coronary artery disease  and is cost-effective when compared with the provision of other medical interventions [25, 26]. Intuitively, it is logical that an appropriately resourced centre managing large numbers of severely injured patients will develop and retain the systems and expertise to enable enhanced care of this patient group. This appears to be the case, with a strong relationship existing between trauma centre case volume and outcome in the most severely injured patients. Significant improvements in mortality and hospital length of stay are evident when annual patient throughput (ISS > 15) exceeds 650 patients per year .
In 1988, it was evident that trauma care in England and Wales was far from ideal. A retrospective, subjective, panel review of coroners reports from eleven regions in England and Wales concluded that nearly one third of all fatalities and two thirds of non-CNS-related deaths were possibly preventable . The preventable rate of non-CNS-related deaths and the key reasons for this (hypoxia, inadequate haemorrhage control, delayed surgery and missed injuries) are remarkably similar to those detected in Orange County almost 10 years previously . A major trauma report in 1988 from the Royal College of Surgeons of England (RCSE) highlighted these deficiencies in UK trauma care  and proposed improvements in the delivery of pre-hospital care, Advanced Trauma Life Support (ATLS) training for hospital doctors receiving trauma patients, improved audit programmes to monitor progress and the formation of a major trauma outcome study (MTOS). However, by the mid ‘nineties, major deficiencies were still very much evident. The first UK MTOS report in 1992 found that junior doctors were responsible for the resuscitation of 57% of severely injured patients and only 46% of those deemed to require urgent surgery were operated on within 2 h. The mortality rate was significantly higher than in a comparable North American dataset, with large inter-hospital variation in mortality . In the north of England in 1995, 35% of major trauma victims died before arrival at the ED, with only 58% of those arriving at hospital alive surviving to hospital discharge . Overall survival from major trauma was only 38% and it was encountered uncommonly in most EDs, accounting for only 0.82% of departmental workload . By 1997, there was evidence of some improvement of the situation in England, Wales and Northern Ireland. From 1989 to 1997, the mortality from trauma reduced by almost 40%. This corresponded with an increase in the involvement of more senior doctors at presentation to the ED . However, during the later half of the ‘nineties no further mortality reductions occurred. This appeared to correlate with no further increase in consultant involvement at presentation and no reduction in pre-hospital times . In 2000, the RCSE recommended the ‘concentration of trauma services and skills’, plus the formation of trauma systems, as well as the formation of trauma teams and the use of ambulance pre-alerts, to try and improve trauma care . In 2003, only 21% of hospitals in England, Wales and Northern Ireland met the recommended standards considered essential to good trauma care by the RCSE . The 2007 National Confidential Enquiry into Patient Outcome and Death (NCEPOD) Trauma: Who cares? provided further evidence of the ongoing deficiencies in trauma care, with 60% of the patients in the study considered by an expert group to have received sub-optimal care . The report predictably found that the study population consisted mainly of young men (75%), including a high proportion of road traffic collisions (55%). More than 60% had head injuries and more than half presented ‘out of hours’. Major trauma accounted for a small percentage of most hospitals’ acute workload, with 91.5% of the hospitals in the study managing fewer than one major trauma patient per week and 14% encountering no major trauma patients during the 12-week study period . These findings were similar to previous UK trauma studies . The report again identified deficiencies in pre-hospital care management and organisation, the trauma team response, initial involvement of consultants and other aspects of in-hospital care. It highlighted the lack of senior staff presence ‘out of hours’ and the resulting lack of appreciation of severity of illness, as well as incorrect and delayed clinical decision making . The report made recommendations to address these issues including the provision of major trauma centres, with centralisation of expertise and resources as part of an inclusive trauma system. The 2010 National Audit Office report Major Trauma Care in England highlighted the same deficiencies and raised others, such as the ‘uncoordinated’ delivery of trauma care, incomplete Trauma Audit and Research Network (TARN) data submission and an absence of any link between or sharing of pre-hospital and in-hospital data. It also stated that major trauma care did not represent good value for money because of the inefficient way in which it was delivered . Given that major trauma makes up such a small proportion of UK hospitals’ workload [29, 33], the principle of concentration of experience as is seen in other specialised areas of medicine [34–37] is a logical step to improve outcome [6, 38–40]. Despite the number of studies reporting poor trauma care in England, Wales and Northern Ireland since 1988 [12, 27–29, 31, 33, 41, 42] and the international evidence of a 15–40% reduction in mortality [16, 21, 22, 40] with the implementation of trauma systems, only modest progress occurred until recently. This lack of development may have been due to concerns over the deskilling of bypassed hospitals , cost , the transferability of mortality data from the US  and failure to establish trauma as a political health priority, combined with a reluctance to embark upon the reorganisation of healthcare systems required to implement effective change . Also, the first study examining trauma system care in England, following the establishment of the experimental trauma system in Staffordshire during the 1990s, found no mortality benefit . However, the trauma system described was basic, the trauma centre would not have met the minimum requirements for a major trauma centre, the population of the study’s catchment area was small and there were many methodological issues with this study. Recent development of formal trauma systems has had to take account of medical and nursing employment changes including the challenges associated with providing trauma services at multiple sites and out of hours while complying with working hour restrictions imposed by the European Working Time Regulations, limited trainee numbers and increased scrutiny of consultant working patterns .
Following the publication of Lord Darzi’s NHS Next Stage Review in 2008, which stated that there are ‘compelling arguments for saving lives by creating specialised centres for major trauma’  and the appointment of the first National Clinical Director for Trauma care to lead the development of regional trauma networks , the political drive for change materialised. Guidance for implementing trauma systems in England was published [3, 46] and 20 years after this need was identified, the London trauma system began operating in 2010, followed by the majority of regional systems in England in April 2012 . Internationally, outside the US and UK, other regionalised systems of trauma care delivery have been adopted [48–53], with reported falls in mortality [40, 42].
In Scotland, Wales and Northern Ireland, formal trauma systems have yet to be implemented. Improvements have been documented and in 2011, for the first time since 2002, the Scottish Trauma Audit Group started collecting data . The 2011 data showed an improvement in survival from major trauma (ISS > 15) from 75% in 2002 to 83% in 2011. The W-statistic also shows an improving trend: there were 1.75 unexpected survivors per hundred trauma patients during 2011 . However, only 60% of victims of major trauma were attended in the ED by a consultant, only 25% of Scottish major trauma-receiving hospitals have trauma teams and 29% of major trauma patients were not triaged to the resuscitation room by the Scottish Ambulance Service [54, 55]. The secondary transfer rate remains high (37%), which is considered detrimental in certain patient groups [56–58] and patients are often triaged to a facility incapable of fully meeting their needs [54, 59]. Change is occurring, with improved ambulance service links, the use of pre-hospital medical trauma teams and the adoption of quality indicators for trauma . The Royal College of Surgeons of Edinburgh’s 2012 report Major Trauma Care in Scotland has clearly stated the case for change, recognising the need for an inclusive trauma system in Scotland, while acknowledging that the most appropriate configuration of such a system requires further investigation . The definitive strategy for the management of trauma patients in Scotland has yet to be defined .
Components of a modern trauma system
A regional trauma system or network consists of a public health model, designed to reduce morbidity and mortality resulting from injury in a specified population . The system is responsible for the entire patient pathway from point of injury and pre-hospital care management, through ED resuscitation and specialist emergency surgical intervention, to reconstruction of injuries and rehabilitation, before reintegration into society . The majority of the published data relating to the benefits of trauma systems relate to victims of major trauma, defined as an ISS > 15. As stated previously, this cohort of patients can gain the most benefit from care in a facility with the expertise and resource to manage the severely injured patient . The ISS is calculated retrospectively, following identification of all injuries, and provides important data for quality assurance and research . However, it is of little use in the pre-hospital environment for triaging patients to the appropriate hospital. Therefore, for trauma system design and operation, major trauma is better defined as any injury that could lead to permanent disability or death, or that is beyond the expertise and capability of the local receiving unit to manage [46, 61].
Pre-hospital emergency medical services, whether paramedic or physician led, need to be closely integrated into the trauma systems governance structure [33, 46, 54]. To provide the full range of time-critical interventions required regularly in victims of major trauma, a physician staffed pre-hospital service is required [33, 61]. This is the model of care seen in many other European countries [62–65]. The doctors staffing these pre-hospital trauma teams should be competent to secure the airway following rapid sequence induction of anaesthesia [33, 66]. Major trauma patients should be identified on scene, with time-critical interventions performed to save life and allow safe transport, followed by rapid transfer to the most appropriate facility for ongoing management. Accurate triage and bypass protocols (whereby patients with major trauma are taken directly to a major trauma centre, potentially bypassing closer EDs) are therefore essential [3, 46, 67, 68]. Helicopter transfer to definitive care has recently been demonstrated to reduce mortality from major trauma , but this is in addition to evidence that physicians bring survival benefits to the pre-hospital phase of trauma care [70, 71].
In the US, trauma centres are designated level I–IV, depending on their capabilities . In the UK, the term major trauma centre (MTC) is used to describe a central hospital that forms the hub of a trauma network and has responsibility for coordinating the management of victims of major trauma in a particular healthcare region . The MTC’s responsibility exists throughout the clinical course, from point of injury until rehabilitation is complete . It is ideal that in the polytrauma patient where multiple clinical specialties may be involved in inpatient management, a consultant-led trauma service team co-ordinates effective care . Dedicated trauma service care provided in an MTC or equivalent has been reported to improve outcome in the US [72–74], Canada , Australia  and England . A clear relationship exists between trauma centre volume and outcome  and current UK guidelines suggest that systems should be organised so that the MTC manages at least 400 cases of major trauma per year and should therefore serve a minimum population of at least 2–3 million people . This may not be possible in some geographical areas. The MTC should provide overall leadership to the whole trauma system . It also has a commitment to providing injury prevention initiatives, education, training and research [46, 67]. Trauma units (TU) should manage less severely injured patients (ISS ≤ 15). The outcome of these patients may not be improved by triage to an MTC and they may even do worse if they are de-prioritised due to the management of more severely injured patients . Trauma units and other local hospitals may still receive major trauma patients due to under-triage errors, self presentation to ED and in managing those patients who require life-saving interventions before the transfer to the MTC for ongoing care [46, 61]. They should be closely linked with and supported by the MTC, via the trauma network. Immediate transfer protocols between the TU and MTC should be in place for the transfer and ongoing management of major trauma patients presenting to the TU [46, 61]. Rehabilitation services in local and specialised facilities should be integrated into the trauma system, with agreed protocols in place to facilitate transfer once treatment at the MTC is completed . Good data on the benefits of rehabilitation after major trauma is scarce , but early, intensive rehabilitation may improve outcome [3, 79, 80]. A robust quality improvement and clinical governance programme, using key performance indicators, should monitor the standard of care provided by the trauma system, implement new strategies and submit data to national trauma registries such as TARN [46, 67].
In comparison with the adult population, the number of paediatric cases of major trauma is small. In England approximately 300 children per annum sustain major trauma , but it remains the leading cause of death in children greater than one year of age . Children are often taken to the nearest ED. There are approximately 180 emergency departments in England , so the presentation of a severely injured child is a rare occurrence in most departments and the risk of poor outcomes related to infrequent practice is significant . There is insufficient paediatric trauma to justify separate trauma networks for children . The question of whether seriously injured children are better served in the initial phase of care in specialist stand-alone paediatric facilities or in higher-throughput adult MTCs with paediatric support is not answered by published data. Treatment of severely injured children at a dedicated paediatric facility has been shown to improve outcome , but does not appear to confer additional benefits over treatment at an adult MTC with onsite paediatric expertise [81, 84]. Paediatric trauma care should be incorporated into evolving adult systems, with agreed mechanisms for the provision of specialist paediatric expertise and integrated functioning with existing paediatric intensive care networks . The MTC should remain the hub of a supported network of smaller units with agreed triage, transfer and bypass protocols .
Inclusive trauma systems
An inclusive trauma system encompasses all trauma-receiving hospitals in a defined area, providing different levels of service provision according to capability. In contrast, exclusive systems focus trauma care solely on the MTC [8, 86]. Inclusive trauma systems have been associated with improved outcomes for victims of major trauma [40, 86]. Concerns of under-triage in inclusive systems seem unfounded, with victims of major trauma no less likely to be triaged to an MTC/Level I trauma centre .
Trauma systems – international differences
Internationally, trauma systems have developed differently, particularly in the provision of pre-hospital care. In Vietnam, military paramedic personnel were tasked with initiating resuscitation under the remote supervision of a doctor , keeping physicians in the receiving hospital. This was largely due to the difficulties and risks of more advanced medical care in the battlefield and the relative scarcity of physicians. As a result, this paramedic-delivered system of pre-hospital care became the model for the civilian system in the US throughout the following decades . In 1950s France, in response to the requirement to transport poliomyelitis patients receiving controlled ventilation to tertiary care, Intensive Care Medicine (ICM) evolved. Suitably resourced mobile critical care units staffed by ICM physicians enabled large reductions in mortality from poliomyelitis to occur. This model expanded to include other clinical situations, becoming the Service d’Aide Médicale Urgente, which has continued to evolve into the current physician-delivered pre-hospital care system attending medical and traumatic emergencies, evident today . Similar systems are present throughout Europe [62–65]. The UK has had a predominantly paramedic-delivered system of pre-hospital care for many years, although differences in training and skill levels exist between paramedics in the UK, the US and elsewhere. Physician-delivered pre-hospital care in the UK is on the increase [87, 88] and is set to continue to do so [33, 43]. The recent approval of pre-hospital emergency medicine as a subspecialty of anaesthesia and emergency medicine in the UK is a key development .
“Mass casualties following disasters and major incidents are often characterised by a quantity, severity and diversity of injuries and other patients that can rapidly overwhelm the ability of local medical resources to deliver comprehensive and definitive medical care”
World Health Organization 2011 .
While major incidents can produce a wide spectrum of disease, the majority are traumatic in origin [90, 91]. There has been increasing concern in recent times of the threat of chemical, biological, radiological and nuclear terrorist attack or accidental release of such agents [92, 93] and evidence exists that this threat is real [94, 95]. However, many recent terrorist major incidents including those in Norway , India , England , and Spain  have resulted in multiple serious injuries and fatalities secondary to bomb and ballistic-related traumatic injuries. Recent worldwide natural disasters have resulted in the majority of casualties’ suffering blunt trauma, crush injury and drowning . Similar patterns of injury are seen in the many hundreds of major incidents that are not reported in the medical literature. An operational trauma system, combined with integrated major incident planning, should enable an enhanced healthcare response to such incidents [46, 61]. Regional major incident planning must take account of local resource and likely local threats . In the event of a non-traumatic mass casualty incident, the integrated pre-hospital and hospital trauma plan can often be adapted and provide an infrastructure for other incident types .
Planning for major trauma has evolved significantly over the past 30 years and continues to do so. A regionalised network of trauma care, with the features of an inclusive trauma system, can reduce the mortality resulting from major trauma. In developed countries with mature trauma systems, further improvements in mortality rates are likely to be small. Therefore, efforts to establish the effect of trauma system care on quality of functional outcome is of key importance. Anaesthetists are involved with all levels of the patient journey from point of injury through to reintegration into society. As trauma systems continue to evolve, anaesthetists in the UK and elsewhere will have a major role to play in the provision of care and quality assurance of trauma care.
Conflicts of interests
No external funding or competing interests declared.