Author: Amaan Siddiqi, MD (Senior EM Resident, Brooklyn Hospital Center) // Edited by: Alex Koyfman, MD (@EMHighAK) and Justin Bright, MD

Basics of Neck Trauma

The neck is a particularly tricky area of assessment and management in the trauma patient, as it is the location for many vital structures. Concern for vascular, neurologic, digestive tract, and airway injury are of paramount importance in the evaluation of these patients, as all can be life-threatening. Oftentimes, the neck trauma patient may appear stable, only to have delayed injury found later, causing increased morbidity and mortality. Neck trauma can be split into penetrating injury and blunt injury.

The neck is divided into 3 Zones, which become important in evaluating and managing these patients, especially with regard to the structures lying within each division.

Zone I (base of neck) – below the cricoid cartilage (to the sternal notch): mediastinal structures, thoracic duct, proximal carotid artery, vertebral/subclavian artery, trachea, lung, esophagus

Zone II (mid-neck) – from the cricoid cartilage to the angle of the mandible: carotid/vertebral artery, larynx, trachea, esophagus, jugular vein, vagus and recurrent laryngeal nerves

Zone III (upper neck) – above the angle of the mandible: distal carotid artery, vertebral artery, distal jugular vein, salivary/parotid glands, CNs 9-12

The struggle with neck trauma lies in the different zones of the neck. Zones I and III are difficult to access and to manage in the operating room, with Zone I injuries at the highest risk. Zone II is the most exposed zone, and is consequently the most likely to be injured. However, Zone II injuries also have the best prognosis because there’s a larger areas of exposure, allowing for easier proximal and distal control.

The incidence of penetrating neck trauma is 0.55-5% of all traumatic injuries. The major mechanisms are GSW, stab wounds, and shrapnel. Stab wounds and lower-velocity GSW cause a 50% lower incidence of clinically significant lesions.

Blunt neck trauma is even more uncommon than penetrating neck trauma. The majority of blunt neck trauma is from MVCs, as well as assault and strangulation. The major issue with blunt trauma of the neck is in missed or delayed diagnosis.

Stable patients should be evaluated for “hard” and “soft” signs. “Hard” signs indicate the need for emergent management, i.e. surgical consult and operative intervention. “Soft” signs indicate close observation and reevaluation, though not necessarily surgical intervention. Per Rosen’s, hard and soft signs are as follows:

Soft Signs

Hemoptysis or hematemesis

Oropharyngeal blood

Dyspnea

Dysphonia or dysphagia

Subcutaneous air or mediastinal air

Chest tube air leak

Nonexpanding hematoma

Focal neurologic deficits

Hard Signs

Expanding hematoma

Severe active bleeding

Shock not responding to fluids

Decreased or absent radial pulse

Vascular bruit or thrill

Cerebral ischemia

Airway obstruction

Management

Start with your ABCs while following ATLS guidelines, as in any trauma situation, with surgical consult at the bedside. We will concentrate on the specific injuries seen in neck trauma that are often encountered, including those easily missed.

Airway + Breathing

Physical signs that warrant immediate airway management include stridor, respiratory distress, shock, or rapidly expanding hematoma. In near-hanging or strangulation victims, you should maintain a very low threshold for intubation. Furthermore, these patients have a propensity to develop pulmonary edema and ARDS.

If in doubt, intubate early – and consider the prophylactic intubation if you anticipate decompensation. A skilled operator should be intubating these patients, as the airway will only become more difficult to secure with time (and with repeat attempts). Direct laryngoscopy is optimal, with orotracheal intubation the method of choice. RSI has been shown to be quite successful in these patients.

Fiberoptic intubation can be considered if a skilled operator is present and the equipment is readily available. Avoid traditional nasotracheal intubation, as it is a “blind” procedure. However, fiberoptic nasotracheal intubation is acceptable if the airway physician is proficient in that technique. If orotracheal or fiberoptic intubation is unsuccessful, be prepared to move quickly to the surgical airway. Time is of the essence, especially if there is an expanding hematoma in the neck that will soon obstruct your anatomy.

Once the airway is secured, other injuries to the larynx or trachea are usually treated surgically in the OR. Concerning signs for emergent surgical intervention include progressive subcutaneous or mediastinal emphysema, pneumothorax, severe dyspnea, or associated esophageal trauma.

Circulation

With any open wound, use caution in spreading the wound. Try not to disrupt any clots, and do not probe through the platysma. If there is concern for internal jugular vein injury, place the patient in Trendelenburg (to avoid an air embolism). If any active bleeding is present, use direct pressure. Do not attempt to blindly clamp vessels, as you do not want to inadvertently cause further injury.

If the patient is unstable (hemorrhagic shock, expanding hematoma, air bubbling through wound, evolving neurologic deficit), he/she should be going right to the OR. The leading cause of immediate death is exsanguination.

Disability

There has been a shift towards removing the C-collar in many of these patients. The thought is that if there is no neurologic deficit and you can evaluate the spine (i.e. patient is not unconscious), then the C-collar can be removed by NEXUS criteria. Though there are no RCTs, there is a great amount of literature supporting this action. Unstable spine fractures are almost always associated with neurologic deficits or AMS.

So if you can remove the C-collar using NEXUS criteria, then remove it. You want to be able to manage any serious airway or vascular injuries without restriction. If unable to clear the cervical spine, then the collar can be partially removed, using in-line stabilization while securing the airway.

Injuries to the spinal cord, brain, and peripheral nerves are rare. Also of note, corticosteroids have no role in spinal cord injury by penetrating trauma.

Esophageal injuries are often missed, and a delay in diagnosis is associated with increased morbidity and mortality, mainly due to the potential for mediastinitis. When surgery is performed within 24 hours post-injury, the survival rate is over 90%. When surgery is performed more than 24 hours post-injury, the survival rate is only 65%. Keep in mind that the leading cause of delayed death in neck trauma is esophageal injury.

Diagnostic Testing

If the patient is unstable, your only goal is getting the patient to the OR as quickly as possible. If stable, a portable chest x-ray, as well as AP/lateral views of the neck should be obtained – to look for any bullet fragments, soft tissue swelling, or air outside the trachea.

Next, we need to determine which of the three zones of the neck are involved. Zones I and III are worrisome areas, and these patients will all be getting vascular imaging. Zone II recommendations have changed over the years, to the point where now CTA is obtained in all three zones of the neck.

The “gold standard” of assessing the vasculature in neck trauma has been conventional angiography, as sensitivities are greater than 99%. Since the advent of multi-slice CT angiography, CTA has overtaken angiography as the first test ordered, as it is faster, less expensive, and non-invasive (and does not require IR). Sensitivity of multi-detector CT angiography is 90-100%, when compared to conventional angiography and surgical exploration. Sensitivity is even better with 64-slice CT.

Duplex ultrasound has been used as well, with a comparable sensitivity to CTA, though it is very operator-dependent, and so is less frequently used emergently.

Angiography is only used if the CTA or duplex sonography is inconclusive or positive (and endovascular intervention is the next step). Multi-slice CT angiography has now supplanted angiography as the test of choice – in all three zones of the neck. It took some time, but Zone II recommendations are now similar to management of the other two zones.

Vascular assessment using CTA should be obtained even in blunt trauma, as there is a high miss rate of vascular injuries in blunt neck trauma – with delayed neurologic sequelae as a result.

Esophageal injuries are often clinically silent, so they ought to be investigated and ruled out. If the patient is stabilized, the EP may not be ordering these further tests, but they will be mentioned briefly. Plain x-rays do not exclude injury to the esophagus. Contrast-enhanced esophagraphy has a sensitivity of 89%, with rigid endoscopy having a similar sensitivity. Flexible endoscopy has a lower diagnostic yield than rigid endoscopy, but has a lower complication rate (i.e. less iatrogenic perforation). When both contrast-enhanced imaging and endoscopy are used, sensitivity approaches 100%.

Disposition

The debate continues between the ideal methods of handling patients with neck trauma – mandatory surgical exploration vs. selective exploration?

The old-school way of thinking was that violation of the platysma and/or Zone II neck injuries necessitated surgical exploration. More recently, however, literature has shown similar diagnostic accuracy in selective exploration. With the advent of high-resolution CTA, we can better assess vascular injury and whether the patient needs to go to the OR.

Even if CTA is negative and the patient is stable, strongly consider admitting these patients for observation. With the multitude of structures in the neck and the potential for delayed identification of injury, decompensation is very possible. Don’t forget that it is very easy to miss esophageal injuries in these patients, as they are often not on the top of differential.

Key Pearls

-Zone I and III injuries and bleeds are particularly difficult to assess control

-The neck houses many vital structures

-Esophageal injury is often missed, and is a cause of delayed mortality

-If in doubt, intubate early or prophylactically

-Get that surgical consult early and often

-CT angiography is the test of choice to assess vasculature

-Clear the C-collar by NEXUS criteria

-Be diligent and watch these patients closely

References

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