Injury is the number one cause of death for people aged 1 to 44. In the US, there were 177,154 trauma deaths in 2009, about two thirds being accidental. Of intentional injury deaths, about 60% were due to self-harm. In addition to deaths, injury results in about 45 million emergency department visits annually.
Patients whose injuries are serious but not immediately fatal benefit the most from treatment in designated trauma centers, hospitals that have special staffing and protocols to provide immediate care to critically injured patients. Criteria for such designation (and for the necessity of transport to them) vary by state but usually follow guidelines of the American College of Surgeons' Committee on Trauma.
Many traumatic injuries are discussed elsewhere in The Manual; for bone and joint injuries, see Overview of Musculoskeletal Injuries; for spinal cord injury, see Spinal Trauma; for head injury, see Traumatic Brain Injury; for facial injury, see Introduction to Facial Trauma; for eye injury, see Overview of Eye Trauma; for genitourinary injury, see Introduction to Genitourinary Tract Trauma; for lacerations, see Lacerations.
Of the myriad ways people are injured, most can be categorized as blunt or penetrating. Blunt injury involves a forceful impact (eg, blow, kick, strike with an object, fall, motor vehicle crash, blast). Penetrating injury involves breach of the skin by an object (eg, knife, broken glass) or projectile (eg, bullet, shrapnel from an explosion).
Other injury types include thermal and chemical burns, toxic inhalations or ingestions, and radiation injury.
All injuries, by definition, cause direct tissue damage, the nature and extent depending on the anatomic site, mechanism, and intensity of trauma. Severe direct tissue damage to critical organs (eg, to the heart, brain, spinal cord) is responsible for most immediate trauma deaths.
Additionally, patients surviving the initial insult may develop indirect injury effects. Disruption of blood vessels causes hemorrhage, which may be external (and hence visible) or internal, either confined within an organ as a contusion or hematoma, or as free hemorrhage into a body compartment (eg, peritoneal cavity, thorax). Small amounts of hemorrhage (ie, < 10% of blood volume) are tolerated well by most patients. Larger amounts cause progressive declines in BP and organ perfusion (shock—see Shock), leading to cellular dysfunction, organ failure, and eventually death. Hemorrhagic shock causes most short-term (ie, within hours) deaths, and multiple organ failure due to prolonged shock causes many of the near-term (ie, first 14 days) deaths. Additional near-term deaths result from infection because of disruption of normal anatomic barriers and immune system dysfunction.
Evaluation and Treatment
Care in the emergency department rather than emergency care delivered at the accident site is discussed here. Evaluation and treatment are done simultaneously, beginning with systems that pose the most immediate threat to life if damaged. Attending to dramatic but not deadly injuries (eg, open lower-extremity fracture, finger amputations) before evaluating immediate life threats can be a fatal mistake. A helpful mnemonic is A, B, C, D, E. Systems are rapidly examined for serious abnormalities (primary survey); a more detailed examination (secondary survey) is done after the patient is stable.
Airway patency is threatened by blood clots, teeth, or foreign bodies in the oropharynx; soft-tissue laxity and posterior retraction of the tongue caused by obtundation (eg, due to head injury, shock, intoxication); and edema or hematoma due to direct neck trauma. These obstructions are readily visible on direct inspection of the mouth or neck; having the patient speak can rapidly confirm that the airway is not likely in immediate danger.
Blood and foreign material are removed by suction or manually. Obtunded patients whose airway patency, airway protective mechanisms, oxygenation, or ventilation is in doubt and patients with significant oropharyngeal injury require endotracheal intubation; usually drugs are given for paralysis and sedation before intubation is done (see Tracheal Intubation). Multiple tools are available to assist with airway management including extraglottic devices, gum elastic bougie, and video laryngoscopy. A CO2 colorimetric device or, preferably, capnography can help confirm proper endotracheal tube placement. If patients require an artificial airway and endotracheal intubation is not possible (eg, due to edema of the airway caused by a thermal burn) or contraindicated (eg, due to severe maxillofacial injury), surgical or percutaneous cricothyrotomy is indicated (see Cricothyrotomy). Note: When evaluating or manipulating a patient's airway, cervical spine immobilization should be maintained (eg, by rigid collar, inline immobilization techniques) until cervical spine injury has been excluded by examination, imaging, or both.
Adequate ventilation is threatened by decreased central respiratory drive (usually due to head injury, intoxication, or nearly fatal shock) or by chest injury (eg, hemothorax or pneumothorax, multiple rib fractures, pulmonary contusion).
The chest wall is fully exposed to look for ample chest wall expansion, external signs of trauma, and paradoxical wall motion (ie, retraction of the chest wall on inspiration), which indicates a flail chest. The chest wall is palpated for rib fractures and the presence of subcutaneous air (sometimes the only finding in pneumothorax).
Adequacy of air exchange is usually apparent on auscultation. Tension pneumothorax (see Pathophysiology) may cause decreased breath sounds on the affected side and distended neck veins; deviation of the trachea to the side opposite the injury is a late finding.
Pneumothorax is decompressed by chest tube see Procedure and must be excluded before initiating positive-pressure ventilation (which may markedly enlarge a pneumothorax and convert it to a tension pneumothorax). Suspected tension pneumothorax can be decompressed with needle thoracostomy (eg, a 14-gauge needle inserted in the midclavicular line, 2nd intercostal space—see Treatment) to stabilize the patient if a chest tube cannot be inserted immediately. Inadequate ventilation is treated with endotracheal intubation and mechanical ventilation. A flail chest is stabilized by applying gentle pressure over the flail segment. An open pneumothorax is covered with an occlusive dressing attached on 3 sides; the 4th side is left untaped to release pressure that might build up and cause a tension pneumothorax.
Significant external hemorrhage can occur from any major vessel but is always apparent. Life-threatening internal hemorrhage is often less obvious. However, this volume of hemorrhage can occur in only a few body compartments: the chest, abdomen, and soft tissues of the pelvis or thigh (eg, from a pelvic or femoral fracture).
Pulse and BP are assessed, and signs of shock are noted (eg, tachypnea, dusky color, diaphoresis, altered mental status). Abdominal distention and tenderness, pelvis instability, and thigh deformity and instability are often present when internal hemorrhage in those areas is large enough to be life threatening.
External hemorrhage is controlled by direct pressure. Two large-bore (eg, 14- or 16-gauge) IVs are started with 0.9% saline or lactated Ringer solution; rapid infusion of 1 to 2 L (20 mL/kg for children) is given for signs of shock and hypovolemia. Subsequently, additional fluids and, if necessary, blood component therapy is given as indicated (see Prognosis and Treatment). Protocols have been developed for patients requiring large volumes of blood products (massive transfusion protocols). When there is strong clinical suspicion of serious intra-abdominal hemorrhage, patients may require immediate laparotomy. Patients with massive intrathoracic hemorrhage may require immediate thoracotomy and possibly autotransfusion of blood recovered via tube thoracostomy.
Neurologic function is evaluated for serious deficits involving the brain and spinal cord. The Glasgow Coma Scale (GCS—see Table 2: Glasgow Coma Scale* and, for infants and children, see Table 3: Modified Glasgow Coma Scale for Infants and Children) and pupillary response to light are used to screen for serious intracranial injury. Gross motor movement and sensation in each extremity are used to screen for serious spinal cord injury. The cervical spine is palpated for tenderness and deformity and stabilized in a rigid collar until cervical spine injury is excluded. With careful manual stabilization of the head and neck, the patient is logrolled onto a side to allow palpation of the thoracic and lumbar spine, inspection of the back, and rectal examination to check tone (decreased tone indicates possible spinal cord injury), the prostate (a high-riding prostate suggests urethral or pelvic injury), and presence of blood. In the US, most patients arriving by ambulance are immobilized on a long, rigid board for ease of transport and to stabilize possible spinal fractures. Patients should be taken off the board as soon as possible because it is quite uncomfortable and pressure ulcers may occur within a few hours.
Patients with severe traumatic brain injury (GCS < 9) require endotracheal intubation for airway protection, brain imaging, neurosurgical evaluation, and therapy to prevent secondary brain injury (eg, optimization of BP and oxygenation, seizure prophylaxis, osmotic diuresis for elevated intracranial pressure, sometimes hyperventilation for patients with signs of impending brain herniation—Fig. 1: Brain herniation.).
To ensure injuries are not missed, patients are completely undressed (by cutting off garments) and the entire body surface is examined for signs of occult trauma. The patient is kept warm (eg, with heated blankets and by using only warmed IV fluids) to prevent hypothermia.
After immediate life threats are assessed and the patient is stable, a more thorough evaluation is done, and a focused history is obtained. If only limited conversation is possible, an “AMPLE” history covers essential information:
After the patient is completely undressed, the examination generally proceeds from head to toe; it typically includes all orifices and a more detailed look at areas examined in the initial survey. All soft tissues are inspected for lesions and swelling, all bones are palpated for tenderness, and range of motion is assessed in joints (unless there is obvious fracture or deformity).
A urinary catheter is usually placed in seriously injured and obtunded patients provided there is no evidence of urethral injury (eg, blood at the meatus, ecchymosis of the perineum, high-riding prostate). Seriously injured patients often also have a nasogastric tube placed, provided there is no serious midface trauma (rare reports exist of intracranial tube insertion through a cribriform plate fracture).
Open wounds are covered with sterile dressings, but cleansing and repair are deferred until completion of evaluation and treatment of more serious injuries. Serious clinically apparent dislocations with marked deformity or neurovascular compromise are imaged and reduced as soon as immediate life threats have been addressed. Obvious or suspected fractures are splinted pending full assessment of serious injuries and appropriate imaging studies. A clinically apparent unstable pelvic fracture is stabilized with a sheet or commercial stabilizing device to help close the pelvic space and decrease bleeding; severe bleeding may require urgent angiographic embolization, surgical fixation, or direct surgical control.
In pregnant trauma patients, initial priority is stabilization of the woman, which is the best way to ensure fetal stability. Fetal monitoring is done if the fetus is > 20 wk gestation and continued for at least 4 to 6 h. An obstetrician should be consulted early for patients with serious trauma or signs of pregnancy complications (eg, abnormal fetal heart rate, vaginal bleeding, contractions). Rh0(D) immune globulin is given to all Rh-negative women following even minor trauma. If the woman has cardiac arrest and cannot be resuscitated, a perimortem cesarean delivery is done if the fetus is > 24 wk gestation.
Imaging tests are the cornerstone; laboratory tests are generally ancillary. Patients with penetrating trauma typically have focal injuries that can limit imaging to the obviously involved region or regions. Blunt trauma, particularly when significant deceleration is involved (eg, serious fall, motor vehicle crash), can affect any part of the body, and imaging is used more liberally. Previously, x-rays or CT of the neck, chest, and pelvis were routinely done on most patients with blunt trauma. However, most trauma centers are now doing only imaging studies that are indicated by the mechanism of injury and findings on examination.
Cervical spine x-rays can be deferred in patients who are not intoxicated, do not have focal neurologic findings, have no midline cervical spine tenderness or distracting injuries (eg, femur fracture), and are awake and alert. All others should have cervical spine imaging, preferably using CT.
Chest x-ray can identify airway disruption, lung injury, and pneumothorax and can suggest thoracic aorta tears (eg, by mediastinal widening). However, chest CT is more sensitive for most intrathoracic injuries and is often preferred.
CT of the chest, abdomen, pelvis, spine, or head or, particularly, combinations of these studies are frequently used for patients who require imaging after severe multiple blunt trauma.
Identification of intra-abdominal injury is essential. Historically, diagnostic peritoneal lavage (DPL) was used to assess for intraperitoneal blood. In DPL, a peritoneal dialysis catheter is inserted through the abdominal wall into the peritoneal cavity. If > 10 mL of blood is aspirated, immediate laparotomy is indicated. If blood is not aspirated, 1 L of 0.9% saline is infused through the catheter and drained out; analysis of the returned fluid is used to guide management. However, DPL has largely been replaced by bedside ultrasonography (FAST examination: focused assessment with sonography in trauma), particularly for unstable patients; it is sensitive for significant volumes of intraperitoneal blood and thus the need for immediate laparotomy. If patients are stable, CT is the preferred study; it is very accurate, allows imaging of the retroperitoneal structures and bones, and shows the volume and sometimes the origin of hemorrhage.
If pelvic fracture is suspected, CT of the pelvis is done; it is more accurate than plain x-rays.
Head CT is typically done in patients with altered mental status or focal neurologic abnormalities and in patients who sustained loss of consciousness. Some evidence suggests that CT is not necessary in patients with brief loss of consciousness (ie, < 5 sec) or transient amnesia or disorientation but who are alert with a GCS of 15 during examination. Imaging is done more liberally in patients with persistent headache, vomiting, amnesia, seizures, age > 60 yr, and drug or alcohol intoxication and in patients taking anticoagulant or antiplatelet drugs.
For children with head injury, the Pediatric Emergency Care Applied Research Network (PECARN) has developed an algorithm that may help limit radiation exposure from head CT (see Fig. 1: Evaluation of Children < 2 yr With a Head Injury); clinical observation is used in children who may otherwise have received CT.
|Evaluation of Children < 2 yr With a Head Injury
||*Include agitation, somnolence, repetitive questioning, and slow response to verbal communication.†Include motor vehicle crash involving ejection of patient, death of another passenger, or rollover; collision of a motor vehicle with a pedestrian or bicyclist not wearing a helmet; and a fall of > 0.9 m for children < 2 yr; and a blow to the head by a high-impact object.‡No other findings suggesting traumatic brain injury, such as only LOC, headache, vomiting, and certain scalp hematomas in children > 3 mo.ED = emergency department; GCS = Glasgow Coma Scale; LOC = loss of consciousness.Adapted from Kupperman N, Holmes JF, Dayton PS, et al for the Pediatric Emergency Care Applied Research Network: Identification of children at very low risk of clinically-important brain injuries after head trauma: a prospective cohort study. Lancet 374: 1160-1170, 2009.|
|Evaluation of Children ≥ 2 yr With a Head Injury
||*Include agitation, somnolence, repetitive questioning, and slow response to verbal communication.†Include motor vehicle crash involving ejection of patient, death of another passenger, or rollover; collision of a motor vehicle with a pedestrian or bicyclist not wearing a helmet; and a fall of > 1.5 m for children ≥ 2 yr; and a blow to the head by a high-impact object.‡No other findings suggesting traumatic brain injury, such as only LOC, headache, vomiting, and certain scalp hematomas in children > 3 mo.ED = emergency department; GCS = Glasgow Coma Scale; LOC = loss of consciousness.Adapted from Kupperman N, Holmes JF, Dayton PS, et al for the Pediatric Emergency Care Applied Research Network: Identification of children at very low risk of clinically-important brain injuries after head trauma: a prospective cohort study. Lancet 374: 1160-1170, 2009. |
Aortic injury should be considered in patients with severe deceleration chest injury or suggestive signs (eg, pulse deficits or asymmetric BP measurements, end-organ ischemia, suggestive findings on chest x-ray); these patients may require CT angiography or other aortic imaging. All patients suspected of having significant blunt chest injury should be placed on a cardiac monitor and have an ECG to detect myocardial injury and arrhythmias. Patients with abnormalities on ECG usually have blood levels of cardiac markers measured and sometimes echocardiography (see Echocardiography).
Vascular injury to the carotid and vertebral vessels should be considered in patients with trauma to the head and neck, particularly those with unilateral neurologic findings, a neck seat belt sign (linear ecchymosis due to the shoulder strap), or a predisposing injury (eg, fracture of C1, C2, or C3, other C-spine fracture with subluxation, hanging mechanism). Such patients typically should have CT angiography.
Plain x-rays are obtained of any suspected fractures and dislocations. Other imaging tests are obtained for specific indications (eg, angiography to diagnose and sometimes embolize vascular injury; CT to better delineate spinal, pelvic, or complex joint fractures).
Laboratory tests that may be useful include serial Hb levels to assess for bleeding, ABGs for Po2, Pco2, and base deficit; urine examination for blood; CBC to establish a baseline to monitor ongoing hemorrhage; glucose to evaluate for hypoglycemia; and type and crossmatch for possible blood transfusion. Measures of perfusion (serum lactate, base deficit on ABG measurement, and, in patients with a catheterized central vein, central venous O2 saturation) are indicated to help identify early or partially treated shock. Other reflexively obtained tests (eg, electrolytes and other chemistries, coagulation studies) are unlikely to be helpful unless suggested by relevant medical history (eg, renal insufficiency, diuretic use). Toxicology screening (eg, blood alcohol, urine drug screen) is often done; results of this testing rarely change immediate management but can help identify substance abuse causative of injury, allowing intervention to prevent subsequent trauma. d-Dimer, fibrinogen, and fibrin degradation products may be measured in pregnant trauma patients. Test results may be abnormal in patients with placental abruption; however, these tests are neither sensitive nor specific and cannot definitively confirm or exclude the diagnosis.
Last full review/revision February 2013 by Jaime Jordan
Content last modified October 2013