TRAUMA CARE

Introduction to Trauma Care

I. Introduction

Trauma is mechanical damage to the body caused by an external force. The trauma patient has been defined as “an injured person who requires timely diagnosis and treatment of actual or potential injuries by a multidisciplinary team of health care professionals, supported by the appropriate resources, to diminish or eliminate the risk of death or permanent disability.” This chapter describes the current impact of injury on society, the structure of modern trauma systems, and finally the way injuries are measured and quantified.

II. Epidemiology

A.

Overall, trauma is the third leading cause of death in the United States and is the leading source of mortality for patients between 1 and 44 years of age. In 2003, 164,002 people died secondary to injury, representing 56 deaths per 100,000 population. Of these, 109,277 were unintentional in nature while 49,639 were caused by violence. A fatal injury occurs approximately every 5 minutes.

B.

Mortality after trauma can be characterized by a well-studied distribution that identifies three time periods during which the majority of deaths occur. Approximately 50% of deaths occur immediately and are usually secondary to > severe neurologic injuries or exsanguination from major blood vessel injuries (Fig. 1-1). These deaths can be avoided only through injury prevention. The second peak of approximately 30% of all deaths occurs during the initial hours postin-jury and preventing these deaths is the goal of modern trauma care, such as is taught through the Advanced Trauma Life Support (ATLS) course. Finally, 20% of deaths occur late (within 1–2 weeks) and are secondary to sepsis and multiple organ failure. It is believed that improved early management of injury and associated shock may prevent these late complications.

Figure 1-1. Distribution of death after injury. (Adapted from Trunkey DD. Trauma. Accidental and intentional injuries account for more years of life lost in the U.S. than cancer and heart disease. Among the prescribed remedies are improved preventive efforts, more expedient surgery and further research. Sci Am 1983; 249:28.)

C.

In 2003, more than 29 million medically attended, nonfatal injuries occurred in the United States. Data from 2002 reveal an estimated 37.8 million injury-related emergency department and 99.2 million office-based visits. There were approximately 1.8 million hospital discharges for injured patients. Injury represents the greatest cause of years of potential life lost (YPLL) before age 65 totaling over 3.4 million years or 29.3% of all YPLL. The total cost for injuries occurring in 2003 including medical expenses, lost wages, property damage, cost to employers, fire losses, and all other costs was estimated to be $607.7 billion.

D. Specific injury patterns and mechanism

• Age. While people 44 years old and younger account for the majority of fatal and non-fatal injuries, the impact of trauma on the elderly is far more severe. The death rate for injuries among patients 0 to 44 years old is approximately 45 per 100,000 population, whereas this rate is 113 per 100,000 for people over 65 years old and 169 per 100,000 for people over 75 years old.
• Gender. Sixty-nine percent of all injury-related deaths occur in males, twice the number of female deaths. The distribution of nonfatal injuries is more equivalent with males representing 55%.
• Mechanism
  • Motor vehicle crashes (MVCs) are the leading cause of injury-related death, accounting for 44,800 deaths in 2003 or 15.4 deaths per 100,000 population. Over 3.5 million people sustained nonfatal injuries secondary to MVC in 2003. Despite this, the death rate per vehicle miles traveled (VMT) has declined steadily throughout the century from 18 deaths per 100 million VMT in 1925 to approximately 5 per 100 million VMT in 1960 to as low as 1.56 per 100 million VMT in 2003. In the 2005 National Trauma Data Bank (NTDB), MVCs accounted for 43.1% of cases and 46% of the mortalities. MVC-related deaths occurred in 4.9% of NTDB cases.
  • Firearm-related injury resulted in 28,827 deaths in 2003 and was the second leading cause of injury-related mortality for all ages in that year. Fifty-nine percent were the result of suicide, while 41% were homicide related. Nonfatal gunshot wounds were identified in 65,834 patients in 2003. Predominately, fatal shootings involve young males, with the number of deaths in the 15-to-34-year-old age range being over seven times that of females. Handguns were involved in 80% of all homicides with a firearm in 2003. Six percent of the injuries in the NTDB were associated with firearms; 16% of cases resulted in death. Firearm-related injuries peaked at 19 years of age.
  • Falls are the leading cause of nonfatal injury resulting in approximately 8.1 million injuries and 17,229 deaths throughout all age groups. Falls are most common among the young and the elderly with both groups demonstrating injury rates of greater than 4,000 injuries per 100,000 population in 2003, twice that of people in the intermediate age groups. Despite this similarity, falls are the leading cause of death in patients 65 years or older while death in children is uncommon. The death rate due to falls in elderly patients is more than 170 times that of children less than 10 years old. Falls in the NTDB accounted for 26% of all cases, with an associated mortality of 3.5%. The peak incidence occurred at age 82.
  • Other common mechanisms contributing to trauma mortality include poisoning, suffocation, drowning, cutting/piercing, and burns. Common non-fatal injuries include struck by/against injury, overexertion, and bites/stings.

III. Trauma Systems

A. Overview

• As defined by the American Trauma Society's Trauma System Agenda for the Future, “A trauma system is an organized, coordinated effort in a defined

  
  

  
  geographic area that delivers the full range of care to all injured patients and is integrated with the local public health system.”
• Historical perspective. The systematic care of trauma changed significantly with the publication of the National Academy of Science/National Research Council's Accidental Death and Disability: The Neglected Disease of Modern Society in 1966. This document revealed the deficiencies in injury management and initiated the development of systems to improve trauma care. The Emergency Medical Services Systems Act was passed in 1973 to support the development of regionalized Emergency Medical Services (EMS) systems. In 1976, the American College of Surgeons (ACS) Committee on Trauma (COT) published Optimal Hospital Resources for the Care of the Seriously Injured which established criteria that identified hospitals as trauma centers. This document has been revised as knowledge about trauma systems has evolved. More recently, the Model Trauma Care System Plan created by the Health Resources Services Administration (HRSA) was published to further define and guide trauma system development.
• Function. Trauma systems have been designed to be inclusive in nature and therefore use all available resources to provide appropriate care to all injured patients and not only to the most severely injured.
• Designation and verification. Facilities within a trauma system require identification of injury management capabilities so that resource assessments can be achieved. A process for designating trauma centers is needed to provide consistent and inclusive care within the trauma system. A government group designates a hospital as a trauma center after evaluating the facility's resources and the ability to provide a specific level of care. The ACS COT performs the process of verification which reviews a facility and ensures that the trauma care provided is in accordance with the Resources for Optimal Care of the Injured Patient document. The criteria for designation and verification may be similar but only designation is the active process of becoming approved to provide a specific level of care.
• Systems consultation. The ACS COT as well as some private organizations provide consulting services that are valuable in evaluation of the status of trauma care either during the development or maintenance of a trauma system.

B. Fundamental components

• Injury prevention has become an essential focus for all trauma systems in order to proactively reduce the impact of injury. Many systems have developed formal injury prevention programs and dedicated centers to better address this need.
• Pre-hospital care includes community access and communication systems as well as EMS systems and triage protocols. Universal access to emergency care (i.e., 911) is essential to allow efficient activation of the system. A robust communication system provides for coordination of pre-hospital resources as well as proper transfer of information to receiving facilities. Standardized curricula for training EMS personnel provide a more consistent knowledge base and skills set. Developed trauma systems have ensured more efficient emergency response through improved geographical placement of EMS providers versus only facility-based responders.
• Acute care facilities provide a range of injury management from initial stabilization and transfer to all-inclusive definitive care. Based on available resources, facilities are characterized by injury management capabilities and many are designated as trauma centers using a scale of 1 to 4, with Level 1 centers providing the most comprehensive level of care. Successful trauma systems benefit from the contributions of all available facilities to become more inclusive and to provide consistent care to all people within the system.
• Post-hospital care is an important part of reducing disability and improving an injured patient's long-term outcome. Efficient transfer from the acute

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  care setting to rehabilitation is a necessary attribute of a well-developed trauma system.

C. Trauma system infrastructure elements

• Leadership. A lead agency should be established to coordinate trauma system development and provide necessary administration.
• Professional resources. Successful trauma systems rely on competent and energetic health care providers to ensure optimal injury care. Recruiting methods to identify and employ the highest quality health care professionals is a necessity.
• Education/Advocacy. Trauma systems must improve public awareness about trauma as a disease state and the ability of injury prevention to reduce the societal impact of trauma.
• Information management. Trauma data registries at the local and national levels provide an invaluable resource for performance improvement, research, and trauma system management. Ideally, trauma data should be consistently captured and incorporated into regional and national databases to provide the most accurate depiction of the status of injury care.
• Finances. Adequate financial support is essential for both trauma system development and the continued provision of trauma care. Increased public and political awareness of the magnitude of the problem is required to improve governmental funding.
• Research. To continue improving the care of the injured, research endeavors must be encouraged and efforts to increase financial support for trauma research is crucial.
• Technology. The potential of novel and developing technologies must be adopted and applied to the field of trauma care. For example, technological advancements have decreased EMS response times and improved crash investigations.
• Disaster preparedness and response. Trauma systems are charged with the task of being prepared to respond to potential disasters by developing a systematic and organized approach that can be implemented if the need arises.

D. State and regional trauma systems

• Each hospital and prehospital agency within a state is encompassed by a state COT that coordinates the fundamental components of the trauma system and implements the infrastructural programs.
• State COTs are grouped geographically into 14 regions that are overseen by a regional committee.
• All state and regional trauma systems are represented by the ACS COT that develops necessary policies to improve trauma care at the national level.

IV. Injury Scoring

A. Principles

• Purpose. Injury scoring systems have been developed to accurately and consistently quantify the magnitude of injury from an anatomic, physiologic, or a combined standpoint. Scoring systems are used in triage decision making, quality improvement and benchmarking initiatives, prevention program analyses, and research endeavors.
• Database use. Scoring systems are commonly included in trauma databases to provide a quantifiable means of patient comparison. Based on the purpose of the database, certain scoring systems may be more appropriate and relevant than others. For example, administrative databases would more appropriately contain International Classification of Diseases (ICD-9) based scoring systems (e.g., ICD-based Injury Severity Score [ICISS]) while trauma registry databases may contain Abbreviated Injury Score (AIS) based scoring systems. Identification of the specific needs of the database often reveals the type of scoring system that would be most applicable.
• Correct use of scoring. While there are many available scoring systems, the use of some of these systems may be limited. Systems used for triage decision

  
  

  
  making must be easy to calculate from rapidly available information. Scoring is commonly used in the research setting and in this case should be able to identify patients with comparable injuries. Evaluation of responses to therapy may benefit from applying a physiologic scoring system. The combined scores are valuable when assessing outcome after injury.
• Limitations. Since every injured patient is unique, there is no single scoring system that can provide a perfect description. Care must be taken when interpreting the results of injury severity scoring to recognize that there will always be aspects of the patient's condition that were not captured.

B. Scoring systems

• Anatomic scores
  • Abbreviated Injury Score (AIS). First proposed in 1969 and updated last in 1990, the AIS assigns a severity level to the worst injury in each of six separate body regions: head/neck, face, thorax, abdomen/pelvic contents, bony pelvis/extremities, and external structures. Level of severity ranges from 1 (minimally injured) to 6 (fatal). The AIS does not account for multiple injuries in the same patient.
  • Injury Severity Score (ISS). ISS was first introduced in 1974 to more accurately characterize severity when multiple injuries were present. ISS is calculated by squaring the AIS scores from the three most severely injured body regions and adding the results. If any AIS is 6, the ISS is automatically 75 and considered to be a fatal injury. ISS is commonly used for injury quantification, although it is limited in that its accuracy requires that all injuries be identified before calculation and it is unable to account for multiple injuries within the same body region.
    • The 2005 NTDB categorized injuries based on ISS as minor (ISS 1–9), moderate (ISS 10–15), severe (ISS 16–24), and very severe (ISS >24). Minor injuries constituted about two thirds (68%) of the injuries with the remainder being nearly equal among the other groups. The average hospital length of stay increased by approximately 3 days for each severity grouping while intensive care unit (ICU) days also increased (moderate = 1.7 days, severe = 3.9 days, very severe = 7.7 days).
  • New Injury Severity Score (NISS). In an attempt to improve on the shortcomings of ISS, NISS was developed in 1997. NISS is calculated similarly to ISS, but the three most severe injuries, regardless of body region, are used in the equation. As a result, NISS is more straightforward to calculate and has been shown to be more predictive of survival than ISS.
  • American Association for the Surgery of Trauma (AAST) Organ Injury Scale (OIS). In 1987 the AAST organized the OIS committee to create an injury scoring system that accurately quantifies the severity of individual organ injuries for clinical investigation and outcomes research purposes. Scales were created from critical review of available literature as well as expert trauma surgeon consensus. Injuries to organs are graded from 1 to 5 to reflect severity and anticipated impact on outcome. Injury scales for abdominal organs—spleen, liver, kidney, pancreas, duodenum, small bowel, colon, and rectum—have been provided (Appendix A).
  • Survival Risk Ratios (SRR)/ICD-based Injury Severity Score (ICISS). Recently, ICD-9 diagnostic codes have been employed to quantify injury severity. Using large trauma databases, SRRs are calculated by determining the mortality observed for each injury-related ICD-9 code. All SRRs for a given patient are then combined to yield ICISS. Because reimbursement depends on ICD-9 codes, the information needed to calculate ICISS is readily available in any hospital data repository. Despite its simplicity, ICISS has been found to be a better predictor of mortality than either ISS or the Trauma and Injury Severity Score (TRISS).
  • Anatomic Profile (AP). The AP incorporates injuries from three body regions: head/spine, anterior neck and chest, and all other injuries. Scores

    • • for these regions are modified and used in an equation derived from logistic regression. The AP has recently been shown to demonstrate good injury model predictiveness compared to other scoring systems.
         
         

        TABLE 1-1 Glasgow Coma Scale
        Eye opening Spontaneous To voice To pain None 4 3 2 1 Verbal response Oriented Confused Inappropriate Incomprehensible None 5 4 3 2 1 Motor response Obeys commands Localizes pain Withdraws to pain Flexion Extension None 6 5 4 3 2 1 Total Glasgow Coma Score 3–15

      • Penetrating Abdominal Trauma Index (PATI). PATI is a scoring system designed to quantify the effects of penetrating abdominal injury. Each organ has a pre-determined risk factor score (1 to 5) and injured organs are assigned a severity score (1 to 5) based on published criteria. The severity score is multiplied by the risk factor score and the sum of all of these results is the PATI.

    • Physiologic scores

      • Glasgow Coma Score (GCS). The GCS is the most widely used scoring system for the characterization of neurologic injury. A patient's status in terms of eye opening, verbal response, and motor activity is determined and summed to calculate the GCS (Table 1-1). A patient's GCS can be rapidly calculated in the field or in the emergency department and is commonly used for patient care decision-making and triage.
        • A GCS of 8 or less is usually indicative of severe brain injury and suggestive of required intervention (e.g., intubation).
        • The motor component of the GCS has been found to correlate well with the entire GCS and be the most predictive of outcome.
      • Trauma Score (TS). The TS was developed in 1981 to incorporate physiologic parameters in severity scoring. Quantification of respiratory effort, systolic blood pressure, capillary refill, and GCS are included in the determination of the TS. Use of the TS has been limited by the subjective nature of respiratory effort and capillary refill assessments.
      • Revised Trauma Score (RTS). The RTS addressed the deficiencies of the TS by removing the ambiguous respiratory and perfusion components. As Table 1-2 demonstrates, coded values are assigned to quantify the GCS, systolic blood pressure, and respiratory rate parameters. The result is a score of 0 to 12 with 12 demonstrating normal physiology. Therefore, the RTS is simple to calculate and is used in making triage decisions and predicting hospital outcomes.
      • Systemic Inflammatory Response Syndrome Score (SIRS Score). The SIRS score incorporates patient temperature, heart rate, respiratory rate, and white blood cell count to physiologically characterize injured patients

        • • (Table 1-3). The SIRS score can be calculated easily and has been demonstrated to be predictive of outcome on admission and further into a patient's hospital course.

          TABLE 1-2 Revised Trauma Score
          A Glasgow Coma Score B Systolic blood pressure (mmHg) C Respiratory rate (breaths/min) Coded value (CV) 13–15 >89 10–29 4 9–12 76–89 >29 3 6–8 50–75 6–9 2 4–5 1–49 1–5 1 3 0 0 0 mmHg, millimeters of mercury.

        • Combined scores

          • Trauma and Injury Severity Score (TRISS). Introduced in 1983, TRISS combines anatomic and physiologic parameters to arrive at a calculated probability of survival. TRISS incorporates the ISS, RTS, patient age, and injury mechanism into an equation that uses established coefficients determined using large trauma databases. TRISS is valuable in outcomes analyses and research but has no value in the patient care setting.
          • A Severity Characterization of Trauma (ASCOT). ASCOT uses a methodology similar to TRISS but has been adapted to better characterize situations where the predictive ability of TRISS is deficient (e.g., penetrating torso injury). ASCOT uses the RTS, patient age, and an anatomic description similar to the AP. ASCOT also employs a logistic regression model to determine survival probabilities. The results of ASCOT assessments have been minimally more predictive than TRISS methodology.
          • Harborview Assessment for Risk of Mortality (HARM). First published in 2000, HARM combines 80 variables such as ICD-9 codes, age, injury mechanism, comorbidities, and injury associations to predict survival probabilities.

        C. Validation of scoring systems

        • After the development of a scoring system, a process of validation is required to confirm its accuracy and predictive nature. This can often be accomplished by challenging the scoring system against a large, well-constructed trauma database such as a state trauma registry, governmental database, or the NTDB.

        TABLE 1-3 Systemic Inflammatory Response Syndrome Score
        Variable Positive result Points Temperature >38°C (100.4°F) or <36°C (96.8°F) 1 Heart rate >90 beats/min 1 Respiratory rate >20 breaths/min, PaCO2 <32 mmHg 1 White blood cell count >12,000/mm3, <4,000/mm3, or ~10% bands 1 Total SIRS Score SIRS defined as ~2 0–4 PaCO2, alveolar carbon dioxide. mm3, cubic millimeters.

        Axioms

        • The impact of trauma on individuals and society as a whole is significant.
        • Organized trauma systems provide the greatest means of combating the substantial effects of injury.
        • Injury severity scoring is an important component of trauma care and careful selection of the most appropriate scoring system will provide the most accurate information.