1 Which trauma patients need to be admitted to the intensive care unit (ICU)?

Patients who are receiving mechanical ventilation or require vasopressor support will obviously be admitted to the ICU. As care has shifted to nonoperative management of many injuries, the ability to closely monitor patients is critical. For example, a patient with a grade 4 splenic laceration who undergoes splenectomy may be able to be managed after surgery on a regular ward, whereas that same patient, if managed without surgery, would likely require closer observation in an ICU.

Examples of trauma patients who may not meet clear-cut “critical care” criteria but who demand close serial observation that is often best carried out in an ICU include those with potential extremity compartment syndrome, nonoperative high-grade solid-organ injuries, significant closed-head injuries, and nonoperative penetrating abdominal trauma. Depending on local capacity a highly monitored observation or “step-down” unit may also be appropriate for these types of patients. If in doubt, admit them to a more-monitored rather than less-monitored setting.

2 What is the top priority when a trauma patient first presents?

Airway evaluation and management are the critical starting point for the evaluation of any trauma patient. Airway compromise is the most important cause of early preventable death in trauma patients. The airway must be secured before further evaluation or treatment is undertaken.

3 How is the airway managed in trauma patients?

Airway management is discussed thoroughly in Chapter 14, but trauma patients can pose a unique set of airway management challenges. Maxillofacial, laryngotracheal, and neck injury; intracranial hypertension; hemodynamic instability; thermal injury to the airway; and the need for maintaining in-line cervical spine stabilization are common conditions that can complicate airway management in trauma.

All trauma care providers should have experience with airway evaluation and management from manual airway maneuvers (e.g., jaw thrust, chin lift), to the use of mechanical airway devices (oropharyngeal and nasopharyngeal airways), to bag-mask ventilation, to rapid-sequence endotracheal intubation, to the use of airway adjuncts such as the bougie or laryngeal mask airway, to establishing a surgical airway. A general algorithm for trauma airway management is shown in Figure 2-1.

Figure 2-1 Algorithm for airway management in trauma. O₂sat, Oxygen saturation.

4 What are the most important causes of hypotension in the trauma patient?

Hemorrhagic shock—bleeding—is the most common cause of hypotension in the trauma patient. A vigorous search for bleeding is the key to the initial evaluation of any trauma patient with hypotension. Even a single episode of hypotension (systolic blood pressure [SBP] < 100-110 mm Hg) should be considered a potential harbinger of serious injury requiring interventional hemorrhage control. Methods for rapid localization of hemorrhage are discussed in Question 5.

Obstructive shock is that caused by tension pneumothorax or pericardial tamponade. Pericardial tamponade is usually diagnosed with the help of ultrasound examination. Tension pneumothorax is usually diagnosed clinically by mechanism and physical examination. Occasionally ultrasound or chest radiographic examination may be of assistance, but one should never wait to obtain these studies when the diagnosis is suspected.

Spinal shock is a form of neurogenic shock that occurs because of the loss of sympathetic tone and peripheral vasodilation that occurs with high (typically T4 level or above) spinal cord injuries. It should be suspected when the patient has had a compatible mechanism of injury, the hypotension is accompanied by bradycardia, and results of the neurologic examination are consistent (lower extremity paralysis, loss of rectal tone, and a compatible sensory level).

Cardiogenic shock may result from traumatic cardiac contusion or occasionally from preexisting cardiac pathologic condition (coronary disease, valvular lesions, congestive heart failure) in patients with other, noncardiac trauma.

5 How can I rapidly identify the source of bleeding in hemorrhagic shock?

Delayed control of bleeding ranks with airway compromise as a major preventable cause of trauma death. To be controlled, the source of bleeding must be rapidly identified. Hypotension due to hemorrhage typically does not occur until a trauma patient has lost 30% to 40% of his or her blood volume. This quantity of blood can be lost only into a limited number of places. The most important of these places are, externally, the chest, the abdomen, the retroperitoneum, and occasionally the thighs. Patients with hypotension should not undergo prolonged imaging such as computed tomography (CT), and all these potential areas of bleeding must usually be evaluated in the emergency department in a matter of minutes. This is possible with reasonable sensitivity for major hemorrhage with use of a combination of physical examination, ultrasound scan, and plain radiography, all modalities that are widely and quickly available.

Physical examination is the most important tool for identifying external sources of bleeding. External bleeding is often missed or underappreciated when it is due to scalp wounds (which can result in significant blood loss); wounds in the back or axillae, which may be missed by a cursory examination; or mangled extremities, which may be diffusely oozing.

Physical examination and chest radiographic examination are the keys to identifying thoracic bleeding. Both can be done quickly. Ultrasound may be a useful adjunct (see extended focused abdominal sonography for trauma [E-FAST] later). If reasonable suspicion exists for intrathoracic bleeding, tube thoracostomy may be both diagnostic and therapeutic.

The abdomen is usually evaluated by FAST. If it cannot be performed, or is technically limited, diagnostic peritoneal aspiration or lavage is an alternative.

The retroperitoneum cannot be directly evaluated without CT, but most hemodynamically significant retroperitoneal bleeding is the result of pelvic fractures, which can be detected on a plain radiograph of the pelvis. Although retroperitoneal bleeding due to pelvic fractures generally correlates with the severity of the fracture, even relatively minor fractures may occasionally produce major hemorrhage. Similarly, femur fractures, especially if bilateral, suggest the possibility of significant hemorrhage into the thighs.

6 What is the role of the FAST examination in evaluating the trauma patient with hemodynamic instability?

The FAST examination has become a standard part of the evaluation of the trauma patient. It involves an ultrasound examination of four locations: the right and left upper quadrants of the abdomen, the pelvis, and the pericardium. The primary role of FAST is to evaluate for hemoperitoneum in patients with blunt trauma who are hemodynamically unstable. In these patients, when no other explanation for hypotension exists, positive FAST examination results can quickly identify the need for laparotomy, saving the time that might otherwise be spent obtaining more involved imaging such as CT. Patients with blunt trauma who are hemodynamically stable but have intraabdominal fluid identified on FAST should not be rushed to the operating room but should undergo CT imaging. Many common injuries, such as splenic and liver lacerations, which can result in positive FAST examination results, do not require surgical exploration and can be better defined on CT, which is safe to perform if the patient is hemodynamically stable. FAST can also identify pericardial tamponade. E-FAST includes sonography of the thorax to assess for hemothorax or pneumothorax. In many centers, FAST is routinely performed even in stable patients to establish a baseline for comparison if the patient’s condition later deteriorates.