Understand the Trauma Triad of Death

An EMS crew responds to a report of a fall from a roof. Upon arrival they find an elderly male patient lying on his right side. He is unconscious, with sonorous respirations. His skin is cool, moist and pale. Bystanders say he was cleaning his gutters when he appeared to slip and fall off the roof. He fell approximately 25 feet onto a hard surface and has not been responsive or moved since the fall.

The crew initiates cervical-spinal immobilization as they rapidly assess the patient and address his ABCs. The man appears to have a significant head injury as well as right chest wall injuries. Bystanders report he has a history of diabetes, congestive heart failure and high blood pressure, and is also a smoker. He has been noncompliant with his medications.

The crew continues to treat the patient while simultaneously preparing for transport to the local trauma center. They load him into the ambulance and start intravenous lines. The patient remains unconscious. En route to the hospital, his vital signs are heart rate 120, EKG showing sinus tachycardia; blood pressure 70/30; respiratory rate 10 and still sonorous.

At the hospital the patient is transferred to emergency department and admitted to the CCU in critical condition. Two weeks later he expires. It is noted that the patient experienced hypoxia, acidosis, hypothermia and disseminated intravascular coagulation (DIC). The emergency physician provides this follow-up to the crew and observes that the patient appears to have experienced the trauma triad of death.

Overview

Prehospital care providers respond to a variety of calls, ranging from relatively benign to life-threatening. Providers need to maintain a core working knowledge of anatomy and physiology, as well as confidence with the assessment and treatment of all patients, regardless of situation. This is especially important in situations where multiple diseases or injuries may be involved, such as the case of the multiple-trauma patient.

Trauma scenarios require providers to consider the immediate needs of the patient while simultaneously anticipating what treatment they may require in the future. A variety of tools and resources can be used to support the provider in providing optimal care. The Golden Hour suggests the critical trauma patient has 60 minutes from the time of injury to reach definitive care. This concept has influenced approaches to trauma resuscitation, such as the goal of reducing the time from injury to incision,^1–4 and in recent years the idea has been applied to settings beyond the field, including the emergency department, operating room and ICU.

In the ED and OR environments, the critical parameter is the time the patient spends there before certain clinical conditions develop. These conditions include hypothermia, acidosis and coagulopathy. Jointly they comprise the trauma triad of death (see Figure 1). While the prehospital treatment of hypothermia, acidosis and coagulopathy is predominantly supportive, it is important for prehospital providers to be familiar with the individual components of this condition; care given in the prehospital setting can help reduce the likelihood a patient succumbs to the trauma triad of death.^5–9

Hypothermia

Hypothermia occurs when the body’s mechanisms for temperature regulation are overwhelmed. The brain’s hypothalamus produces hormones that influence a variety of bodily functions, including body temperature. Core body temperature normally ranges between 36.5–37.5°C (see Table 1). Hypothalamic control of temperature occurs through several mechanisms, including heat conservation with peripheral vasoconstriction and heat production through shivering, influenced by epinephrine (Figure 2). Heat production increases with muscle contractions and shivering. Some consider shivering one of the last resorts by which the body attempts to maintain temperature.^{1–7,10–14}

Heat loss occurs through several mechanisms. The most significant in the trauma setting is often radiation, which can account for more than half of total heat loss. Conduction and convection, which involve the direct transfer of heat to another object or circulating air, are the most common causes of accidental hypothermia. Heat loss through conduction in water is significant, as the thermal conductivity of water can be over 25 times greater than that of air. Other sources of heat loss include respiration and evaporation.^10–14

Hypothermia can impact any organ or system. It can also contribute to the development of acidosis due to decreased tissue perfusion, shivering and a decrease in the removal of lactic acid from the body.^10–14 These events can lead to a decrease in oxygen utilization and an increase in carbon dioxide production.

The impact of hypothermia in the clinical setting will vary by situation. For example, in a medical or post-medical cardiac arrest, hypothermia can have therapeutic benefits. In contrast, hypothermia in trauma cases has been shown to worsen overall condition. A mainstay in trauma care is to avoid it.^15–17

There are numerous signs and symptoms associated with hypothermia, including confusion, dizziness, chills, dyspnea, mood change and irritability. In situations of more severe hypothermia, the patient may demonstrate paradoxical undressing—removal of clothing in response to prolonged cold stress. Slurred speech and/or ataxia may mimic a stroke or alcohol intoxication (see Table 2).^{2–4,10–14}

The prehospital treatment of hypothermia should be focused on maintaining the patient’s core body temperature and preventing any further heat loss. This can be challenging in the prehospital setting. Studies have shown that patients with severe injuries and warmer body temperatures tend to experience less hemorrhage than patients with cooler temperatures. This highlights the importance of avoiding the combination of trauma and hypothermia.^13,14

When treating trauma patients, providers are encouraged to avoid unnecessarily or excessively exposing them to cooler environments, such as cold air, rain or snow, and provide a warmer environment if possible. Remove cold, wet clothing and replace it with dry blankets. These are simple yet important steps to support the patient’s body temperature. If possible, avoid infusing cold or cool intravenous fluids, as this can contribute to reducing body temperature. If allowed, active warming in the field may be initiated with caution. Overly aggressive rewarming can lead to pulmonary edema, reduced cough reflex and excessive bronchial secretions.^{2–4,10–14}

Acidosis

Acidosis is the result of excessive acid accumulation in body fluids. Causes include excessive acid in the blood, decreased clearance of acidic byproducts, loss of bicarbonate from the blood, buildup of carbon dioxide in the blood resulting from poor lung function, and slow breathing.^10,18–23

A normally healthy body maintains a balance of hydrogen ions (acids) through buffers. This involves the interaction of acids, bases and the proper pH level. The pH level is a measure of acidity rated on a scale of 0–14. Values less than 7.0 are considered acidic; those above 7.0 are basic (alkalotic; see Figure 3). Normal pH of the blood is between 7.35–7.45.

Recall that the buffer system includes plasma proteins, hemoglobin in red blood cells, sodium bicarbonate (NaHCO₃) and carbonic acid (H₂CO₃). The renal (kidneys) and pulmonary (lungs) systems are also important in maintaining homeostasis (Figure 4). A change in one component can influence any other.^10,18–23

There are different forms of acidosis. Diabetic ketoacidosis, or DKA, develops when ketone bodies (acids) accumulate during uncontrolled diabetes. Lactic acidosis develops when metabolism occurs in the setting of low oxygen, resulting in the accumulation of lactic acid. Respiratory acidosis develops when there’s excessive carbon dioxide, which can be caused by a decreased ability to remove carbon dioxide through effective breathing (Table 3).^18–23

Metabolic acidosis can be caused by several different pathways.^18–23 In metabolic acidosis, the lungs and kidneys try to compensate. If the acidosis continues, the body’s pH buffering system can be overwhelmed. This can result in lowered blood pH, triggering stimulation of the central nervous system, resulting in tachypnea. Tachypnea can increase the amount of carbon dioxide exhaled. The renal system may compensate by excreting more acid in the urine. Both mechanisms can be overwhelmed if the body continues to produce too much acid, leading to severe acidosis and eventually, if not reversed, death.^18–23

Many symptoms of acidosis can be similar to those of underlying diseases or medical conditions. Symptoms can include tachypnea, tachycardia, bradycardia, dysrhythmias, vasodilation and hypotension, altered mental status, nausea, vomiting and fatigue. While it’s not always possible to differentiate the symptoms of respiratory and metabolic acidosis in the field, respiratory acidosis may include headaches, confusion and bradypnea. Metabolic acidosis can include tinnitus (ringing in the ears), vertigo, blindness, blurred vision, visual changes, photophobia (fear of light), tachycardia, palpitations, chest pains, hyperventilation, dyspnea, headache, altered mentation, nausea, vomiting, abdominal pain, diarrhea, polyphagia and generalized muscle weakness.^{2–4,18–23}

Prehospital treatment of acidosis should focus on managing the suspected cause (e.g., the injury) and contributing underlying diseases. In the setting of multisystem trauma, management of hypoxia and hypoperfusion is important. Providers should ensure that the patient’s airway is patent and oxygen is administered. Recalling that hypovolemia and hypoperfusion can lead or contribute to acidosis, give intravenous fluids per local protocol. In the prehospital setting, administering medications such as sodium bicarbonate to overcome acidosis is rarely indicated.^{2–4,18–23}

Coagulopathies

Coagulopathies, or bleeding disorders, can result from a number of different events, including excessive fluid dilution, metabolic events (e.g., acidosis), hypothermia and disseminated intravascular coagulation (DIC).

When a healthy person is injured, proteins in the blood become activated and travel to the site of injury to assist with clotting. In normal situations the clotting factors are replaced as they are consumed. In DIC widespread thrombus formation occurs, along with depletion of platelets and clotting factors. This leads to clotting complications, clot breakdowns and an inflammatory response by the body. As a result, small blood clots begin to form in the blood vessels; these can occlude vessels and cut off blood supply to organs. As this cycle continues, clotting factors are consumed, and simultaneous hemorrhage and thrombosis can occur. The systemic activation of the coagulation process leads to depletion of coagulation factors as clots are formed and broken down.^6–8,24,25

Symptoms associated with DIC include hemorrhage, renal complications, hepatic dysfunction, respiratory compromise, hypotension, tachycardia, CNS dysfunction, epistaxis, gingival bleeding, mucosal bleeding and fever. Skin abnormalities can include petechiae (small red or purple spots on the body), jaundice (yellowish pigmentation of the skin indicating liver dysfunction) and purpura (red or purple discolorations on the skin that do not blanch when pressure is applied). Acral cyanosis (persistent blue or cyanotic discoloration of the extremities), skin necrosis on the lower limbs, gangrene, wound bleeding and deep subcutaneous hematomas may occur.^{2–4,24–25}

Prehospital treatment options for coagulopathies are limited and tend to be supportive. Providers should focus on securing the patient’s ABCs, administering supplemental oxygen, managing external hemorrhage with direct pressure, wound care, maintaining the patient’s temperature, and providing overall support.^2–4,24,25

Prehospital Care Considerations

As with any situation, providers should ensure that the basics of patient assessment and treatment take priority. Prehospital treatment is likely to be the foundation for continued treatment in the hospital.

Assessment—The patient assessment should begin with an overview of the patient’s overall appearance. When possible, obtain a detailed physical assessment, review of systems and detailed medical history. Questions to consider include: What is the patient’s level of consciousness? Do they have a chief complaint? Do they appear to be in obvious distress? Are there clues on scene that reveal a possible cause of their symptoms, such as obvious signs of trauma?^{2–4,26–29}

When assessing a trauma victim, a rapid assessment to identify life-threatening injuries is essential. Critical interventions may include airway management, thoracic decompression, application of direct pressure for external hemorrhage, and avoiding on-scene delays before beginning rapid transport to the closest appropriate facility.^{2–4,26–29}

A rapid patient assessment can be completed in less than 60 seconds. Providers can perform this using the acronym ABCDE (for airway, breathing, circulation, disability and exposure).^2–4 These components can often be performed simultaneously. For example, after opening the patient’s airway, it is not necessary to pause for 30 or 45 seconds to assess the patient’s breathing before determining what intervention to consider. Rather, once the patient’s airway is opened, their respiratory quality, effort and effectiveness can be quickly assessed. After exposing the patient, apply covers or blankets to help maintain their body temperature. Providers can also simultaneously begin to determine the next sequence of steps for both assessment and treatment. A variety of tools can be used to assist with the rapid assessment, including capillary refill time, the AVPU mnemonic (alert, verbal, painful, unresponsive) and Glasgow Coma Scale score.^{2–4,26–29}

Focused assessment—Following the initial rapid assessment, the provider should perform a more detailed, or focused, head-to-toe assessment when time and patient condition allow. This should begin with visual inspection, followed by hands-on assessment. This includes noting the presence of DCAP-BTLS: deformity, contusion/crepitus, abrasions, penetrations/paradoxical movement, burns, tenderness, lacerations and swelling. Life-threatening situations, such as tension pneumothorax, should be managed immediately in accordance with local protocol. Examine the patient’s head, neck, chest, abdomen and extremities. Any abnormal findings should be suspected as indicative of traumatic injury.^{2–4,26–31}

If time permits, obtain a detailed medical history. This can be accomplished using the SAMPLE approach: signs and symptoms, allergies, medications, past medical history, last meal eaten and events leading up to this episode. Additional questions may include: What (if any) events occurred prior to this episode? Has this episode remained consistent since onset, or has it varied? Has anything relieved the symptoms? Has the patient taken any medications? Is there a report of alcohol or substance abuse? If the patient is female, is pregnancy possible?^{2–4,26–31}

Obtain a complete set of vital signs, including heart rate, EKG, blood pressure, skin temperature and respiratory rate, as early as possible. Rapidly assess and monitor breath sounds and respiratory effort. Reassess vital every 10 minutes, or more frequently as needed.^{2–4,26–31}

Treatment

Treatment will be influenced by a number of factors, including the severity of the patient’s condition, mechanism of injury, level of services available in the field and local protocols. Recall that the management of immediately life-threatening traumatic injuries (e.g., uncontrolled bleeding) should take priority over management of non-life-threatening conditions (e.g., extremity fractures). The presence or suspicion of injuries must also be considered when determining destination. If multisystem trauma is involved, the patient may initially be transported to a trauma center for resuscitation, then transferred later if needed. Spinal immobilization may be indicated. Providers should consult their local protocols regarding indications and technique.^{2–4,26–33}

Treatment should always start with securing the patient’s ABCs and managing any life threats. Manage the airway, using manual support as needed. This can range from the simple jaw thrust to endotracheal intubation. Airway management and administration of supplemental oxygen are mainstays of resuscitation efforts. Consider administering oxygen whenever hypoxia and/or acidosis is anticipated or suspected.^2–4

After securing the patient’s ABCs and managing any life-threatening injuries, subsequent treatment can begin. This may include wound care, establishing IV access and fluid resuscitation. When an intravenous line is started, blood work may be obtained according to local protocols.^2–4

Take care to proactively maintain the patient’s body temperature. This is especially important in scenarios where IV fluid administration is involved. To avoid hypothermia, consider basic measures such as warming the patient compartment, ensuring the patient is covered and administrating warm IV fluids.^2–4,27,31

Administering intravenous fluids is often indicated in trauma patients. One goal of fluid resuscitation is to allow for the perfusion of vital organs without overhydrating the patient, which may worsen bleeding. Normal saline and lactated Ringer’s are appropriate crystalloid solutions for initial resuscitation in the prehospital setting. IV flow rates and volumes will vary depending on factors including patient age, symptoms and/or injuries, as well as local protocols. When infusing intravenous fluids, monitor the patient’s temperature. Cooler fluids may have a significant impact on core body temperature.^2–4,27,32

Depending on the patient’s condition, it may not be possible to obtain traditional peripheral intravenous access. Intraosseous access and infusion is an option that can be used in the prehospital setting. Consult local protocols regarding the use of this procedure.^2–4

Additional prehospital treatment will be influenced by a variety of factors, including the patient’s chief complaint and overall condition, and provider judgment. Pain management may be indicated. While medications and specific routes of administration may vary, fentanyl, morphine and Dilaudid are effective in managing pain. If the patient has an altered mental status, focus treatment on the underlying cause, such as hypoxia, hypoglycemia or narcotic ingestion. Potential cardiac findings, such as an irregular heartbeat, palpitations or chest pain, may warrant continuous cardiac monitoring.^5–7 Factors such as the patient’s age, injuries, vital signs and overall condition will need to be considered.^2–4

The specific management of injuries will vary and depend on factors such as the nature of the injury, provider judgment and local protocols. Manage external hemorrhage through the application of direct pressure, use of pressure points and a tourniquet if indicated. Manage suspected fractures using appropriate techniques, including immobilization when indicated.^2–4,34

The following are some key reminders to keep in mind when managing a trauma patient and trying to avoid the trauma triad of death.

Head injuries—A priority is to ensure that the patient has an open airway and supplemental oxygen is administered. These steps, which can often be completed simultaneously, are critical when treating for, or attempting to avoid, hypoxia or anoxia. An open airway and oxygen administration also can help avoid the cascade of events involved in the trauma triad of death.

Neck trauma—Manage this in accordance with local protocols. Remain aware of potential airway compromise. The presence of internal or external neck injury or hemorrhage must always trigger consideration of airway implications, to avoid hypoxia and ensure the patient has an open airway. Manage external hemorrhage with direct pressure. Consider IV fluid administration.

Chest injury—This requires the provider to consider numerous factors involved in the trauma triad of death, including hypoxia, hemorrhage and perfusion. The presence of a tension pneumothorax may require needle decompression. Treating an open chest injury may include use of an occlusive dressing. A flail section or asymmetrical chest may require applying a bulky dressing. Penetrating chest trauma considerations should include internal bleeding/injury and management of hypoxia. Airway management, including assisting and/or supporting the patient’s ventilations, and administration of oxygen are key interventions. Intravenous fluids, fluid selection, volume and rate of administration should be in accordance with local protocols. Take care during fluid administration to avoid overload.

Abdominal trauma—Scenarios can encompass open and closed wounds, internal and external hemorrhage, penetrating injuries and evisceration. Airway management and supplemental oxygen will be important in avoiding hypoxia. Manage hemorrhage in accordance with local protocols. Impaled objects may require the use of a bulky dressing in addition to direct pressure. Evisceration may be managed with an occlusive dressing. Administer fluid in accordance with protocols. Focus treatment on the optimal delivery of oxygen and supporting circulation in an effort to avoid the development (or progression) of hypoxia and acidosis.

Pelvic injuries—Manage these in accordance with local protocol. This may include managing the patient’s ABCs, giving oxygen, fluid resuscitation as indicated, and immobilization and/or splinting of the pelvic area. A possible pelvic injury should cause suspicion for abdominal injuries. Due to the vasculature and organs present in the pelvic region, consider internal hemorrhage.

Extremity injuries—Manage these also by protocol. This may include applying direct pressure to external hemorrhage, splinting deformities and limiting the extremity’s movement. Movement of an injured extremity may produce or worsen injury to blood vessels, muscle and bone. This can result in distal tissue ischemia, hypoxia and potentially necrosis (death). These factors can lead to systemic implications that include hypoxia and acidosis.          

Patient destination—In addition to treatment, providers must also consider patient destination. Recall that trauma treatment takes priority over other conditions. If the patient has trauma as well as coexisting medical problems, the most appropriate facility will often be the local trauma center, if one is available. The trauma center can transfer the patient to another specialty center when indicated. In areas where trauma centers are not immediately available, providers may need to transport to the local hospital for initial resuscitation efforts. Once resources such as air transport are available, the patient may be transferred to a higher level of care.^2–4,31

Conclusion

Trauma scenarios require providers to be able to identify obvious injuries as well as suspect internal injuries while simultaneously understanding how field management may prevent complications that directly affect patient outcomes. The trauma triad of death is one example of this. The provider who can assess, identify and treat a patient while simultaneously appreciating and preventing the trauma triad of death will be effective in reducing trauma-related morbidity and mortality. This approach to trauma care is essential, as once the patient develops hypothermia, acidosis and DIC, it is most often not reversible, and mortality greatly increases despite resources available in the trauma center setting.

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Paul Murphy, MSHA, MA, is a regional sales manager with InTouch Health. He has administrative and clinical experience in healthcare organizations.

Chris Colwell, MD, is medical director for Denver Paramedics and the Denver Fire Department, as well as director of emergency medicine at the Denver Health Medical Center.

Gilbert Pineda, MD, FACEP, is medical director for the Aurora Fire Department and Rural/Metro Ambulance of Aurora, CO, as well as an attending physician in the emergency department at The Medical Center of Aurora and Denver Health Medical Center.