Neck Trauma Management

Structures at risk

The pathophysiology of neck injury depends on the mechanism of injury. The neck contains many critical organ systems adjacent to one another. For this reason,  even innocuous-appearing wounds have the potential to cause immediate or delayed life-threatening injuries or complications. A cervical injury without a neurologic deficit is rare in patients with penetrating neck trauma.[3]

With the neck protected by the spine posteriorly, the head superiorly, and the chest inferiorly, the anterior and lateral regions are most exposed to injury. The larynx and trachea are situated anteriorly and are therefore readily exposed to harm. The spinal cord lies posteriorly, cushioned by the vertebral bodies, muscles, and ligaments. The esophagus and the major blood vessels are between the airway and spine.

Two fascial layers invest the neck: the superficial fascia (enveloping the platysma muscle) and the deep cervical fascia. The deep cervical fascia envelops the sternocleidomastoid and trapezius muscles, as well as demarcates the pretracheal region (including the trachea, larynx, thyroid gland, and pericardium), the prevertebral area (containing the prevertebral muscles, phrenic nerve, brachial plexus, and axillary sheath), and the carotid sheath (enclosing the carotid artery, internal jugular vein, and vagus nerve).

Musculoskeletal structures at risk include the vertebral bodies; cervical muscles, tendons, and ligaments; clavicles; first and second ribs; and hyoid bone.

Neural structures at risk include the spinal cord, phrenic nerve, brachial plexus, recurrent laryngeal nerve, cranial nerves (specifically IX-XII), and stellate ganglion.

Vascular structures at risk include the carotid (common, internal, external) and vertebral arteries and the vertebral, brachiocephalic, and jugular (internal and external) veins.

Visceral structures at risk include the thoracic duct, esophagus and pharynx, and larynx and trachea.

Glandular structures at risk include the thyroid, parathyroid, submandibular, and parotid glands.

Associated structures at risk of intrathoracic injuries include the esophagus, tracheobronchial tree, lung, heart, and great vessels.

Anatomic zones

Dividing the neck into anatomic zones or regions assists in the evaluation of injury. Serving as the line of demarcation, the sternocleidomastoid separates the neck into anterior and posterior triangles. Most of the important vascular and visceral organs lie within the anterior triangle bounded by the sternocleidomastoid posteriorly, the midline anteriorly, and the mandible superiorly. Except for individual nerves to specific muscles, few vital structures cross the posterior triangle, which is delineated by the sternocleidomastoid, the trapezius, and the clavicle (with the exception of the region just superior to the clavicle).[2, 12]

For clinical purposes, the neck is partitioned into 3 zones (as shown in the image below).

Zone I (as illustrated in the image below), the base of the neck, is demarcated by the thoracic inlet inferiorly and the cricoid cartilage superiorly.

Structures at greatest risk in this zone are the great vessels (subclavian vessels, brachiocephalic veins, common carotid arteries, aortic arch, and jugular veins, trachea, esophagus, lung apices, cervical spine, spinal cord, and cervical nerve roots). Signs of a significant injury in the zone I region may be hidden from inspection of the chest or the mediastinum.

Zone II (as illustrated in the image below) encompasses the midportion of the neck and the region from the cricoid cartilage to the angle of the mandible.

Important structures in this region include the carotid and vertebral arteries, jugular veins, pharynx, larynx, trachea, esophagus, and cervical spine and spinal cord. Zone II injuries are likely to be the most apparent on inspection and tend not to be occult. Additionally, most carotid artery injuries are associated with zone II injuries.

Zone III (as seen in the image below) characterizes the superior aspect of the neck and is bounded by the angle of the mandible and the base of the skull.

Diverse structures, such as the salivary and parotid glands, esophagus, trachea, vertebral bodies, carotid arteries, jugular veins, and major nerves (including cranial nerves IX-XII), traverse this zone. Injuries in zone III can prove difficult to access surgically.

Types of trauma

Penetrating trauma

More than 95% of penetrating neck wounds result from guns and knives, with the remainder resulting from motor vehicle accidents, household injuries, industrial accidents, and sporting events. Generally, a gunshot wound (GSW) causes greater injury than a stab wound because of a bullet's proclivity to penetrate deeper and cause cavitation, thus damaging structures lying outside the tract of the missile.[2, 13, 14, 15, 16] ​[17]

High-velocity bullet wounds (>2000-2500 ft/s) tend to follow a direct and predictable pathway, while low-velocity bullets travel a more erratic pathway, often demonstrating no direct relationship to the entrance or exit wounds. Additionally, high-velocity bullet wounds produced by military-style weapons or hunting rifles generate shock waves that devitalize surrounding tissues. High-velocity missiles and their ensuing blast effects may suck debris into the wound tract or cause secondary injuries from bullet or bone fragmentation. Low-velocity injuries may be produced by .22-caliber and .38-caliber handguns that have a muzzle speed of 300 ft/s to 800 ft/s. Furthermore, lower-energy injuries (knife, handgun, long-range birdshot or buckshot) are associated with 50% less frequency of clinically significant injuries regardless of zone of injury.

A lateral transcervical GSW is more likely to cause a grave injury than a GSW involving injury to only one side of the neck. Close-range GSWs of the neck that produce massive destruction are usually fatal. After a GSW to the neck, surgery is indicated in 75% of cases, whereas only 50% of neck stab wounds require surgical exploration.

Vascular injuries arising from penetrating trauma may occur directly, causing a partial or complete transection of the vessel or inducing formation of an intimal flap, arteriovenous fistula, or pseudoaneurysm. Injury to the blood vessels can also result from external compression or mural contusion. Thrombosis is the most common complication of blood vessel injury, occurring in 25-40% of patients.

The internal jugular vein (9%) and carotid artery (7%) are the most common sites of vascular injuries. Injury to the pharynx or the esophagus occurs in 5-15% of cases. The larynx or the trachea is injured in 4-12% of cases. Major nerve injury occurs in 3-8% of patients sustaining penetrating neck trauma. Spinal cord injury occurs infrequently and almost always results from direct injury rather than secondary osseous instability.

Blunt trauma

Blunt trauma to the neck typically results from motor vehicle crashes but also occurs with sports-related injuries (eg, clothesline tackle), strangulation, blows from the fists or feet, and excessive manipulation (ie, any manual operation such as chiropractic treatment or physical realignment or repositioning of the spine).[7, 8]

In motor vehicle crashes in which the driver is not belted, the driver is in danger of thrusting forward with the head extended, forcing the anterior neck against the steering column. Shoulder harnesses appear to offer some, though incomplete, protection against blunt neck trauma; cerebral vessel and laryngeal injuries secondary to shoulder strap compression have occurred.

Nonpenetrating trauma can injure a blood vessel through a multitude of mechanisms.

Direct forces can shear the vasculature. Excessive rotation and/or hyperextension of the cervical spine causes distention and stretching of the arteries and veins, producing shearing damage and resultant thrombosis. Intraoral trauma may extend to the cerebral blood supply. Basilar skull fractures may disrupt the intrapetrous portion of the carotid artery.[10] Impact to the exposed anterior aspect of the neck may crush the larynx or the trachea, particularly at the cricoid ring, and compress the esophagus against the posterior spinal column. A sudden increase in intratracheal pressure against a closed glottis (eg, improper wearing of a seat belt), a crush bruise (eg, clothesline tackle), or a rapid acceleration-deceleration action may cause a tracheal injury.[18]

A multidisciplinary approach is required for management of blunt trauma. Airway control has the highest priority at the time of initial care. Management of airway, breathing, and circulation must be tailored to the patient. Decisions regarding airway management, ventilation strategies, monitoring, and fluid and blood administration should be based on the patient's condition, the clinical setting, and available personnel, expertise, and equipment.[19]

Near-hanging or strangulation

Strangulation may result from hanging (partial or complete suspension of the body from the neck), ligature suffocation, manual choking, and postural asphyxiation (eg, seen in children when the neck is placed over an object and the body weight produces compression). Significant cervical spine and spinal cord damage occurs in only those hangings that involve a fall from a distance greater than the body height. Simple asphyxiation is not the major cause of death in hanging injuries. Cervical spinal disruption subsequent to strangulation is almost uniformly fatal.

External neck pressure causes cerebral hypoxia due to venous and arterial obstruction.

Penetrating trauma injuries include gunshot wounds and stab wounds.[2, 14, 15, 16]  Blunt trauma includes the following[6, 7, 8] :

• Motor vehicle crash injuries, such as padded dash syndrome, whereby an unrestrained front seat occupant sustains injury to the anterior neck structures striking the steering column or dashboard

• Sports-related injuries and clothesline injuries, where the rider of a motorcycle, snowmobile, all terrain vehicles (ATVs), horse, or bicycle runs into an unseen wire or tree limb[7]

• Strangulation

• Blows from fists or feet

• Excessive manipulation (eg, any force causing a realignment or repositioning of the spine, including iatrogenic carotid or vertebral injury resulting from chiropractic treatment)

Neck trauma accounts for 5-10% of all serious traumatic injuries and carries high rates of morbidity and mortality, as several vital structures can be damaged.[20]  The most common mechanism of injury worldwide is a stab wound from a violent assault (causes serious injury in 20-30%, with overall mortality of 5%), followed by gunshot wounds (up to 50% are accompanied by significant injuries, with mortality of 10-15%), self-harm, road traffic accidents, and injury by other high-velocity objects.[3, 21]  Approximately 3500 people die every year from neck trauma secondary to hanging, suicide, and accidents. The most common cause of death from penetrating neck trauma is vascular injury. The most common cause of delayed mortality is esophageal injury, which may not be apparent on initial presentation.[3]

Trauma is more common in males than females, and most people who experience neck trauma are adolescents and young adults. 

In a study by Stone et al of data in the National Trauma Data Bank (NTDB), 1,238 pediatric patients (defined as < 15 yr), or 0.28% of  children in the NTDB, received penetrating neck trauma over a 4-year period. Mean age was 7.9 years, and 70.6% of patients were male. The most common mechanisms of injury were stabbing (44%) and gunshot/firearm (24%). About 24% went directly to the operating room from the ED. Mortality was 5.6%, with vascular injury and hypotension on presentation being independently associated with mortality.[14]

 

As a general rule, zone I injuries have the worst prognosis in regard to imminent morbidity and mortality.

Zone II injuries are the most prevalent penetrating neck wounds.[22] Because of their accessibility, injuries in zone II have the best prognosis.

Zone III presents unique therapeutic and diagnostic challenges because of its secluded nature of the critical structures spanning this locale.

Complete disruption of the spinal cord above C4 is frequently fatal. Preservation of any neurologic function, including rectal tone, following a spinal cord injury improves the outlook.

Vascular injuries arising from blunt trauma are associated with a poor outcome.

The prognosis is poor when severe neurologic deficits (eg, hemiparesis, coma) occur subsequent to carotid artery damage. Early revascularization may improve the outlook.

Identification of pharyngeal or esophageal injuries is paramount because delayed diagnosis leads to significant morbidity.

Strangulation patients who present in cardiac arrest have a dismal prognosis, as do strangulation patients who are successfully resuscitated but who completely lack neurologic function. If the Glasgow score is greater than 8, the chances are good that the patient with a choking or strangulation injury will eventually be discharged neurologically intact.

During the Vietnam era, when mandatory exploration and vascular repair was the standard of care for penetrating neck wounds, the mortality rate for the civilian population was 4-7%. Today, the overall mortality rate has decreased to 2-6%. Studies from Operation Iraqi Freedom reveal the perioperative mortality rate and the positive exploration rate for high-velocity penetrating neck trauma by deployed surgeons are very comparable to those rates seen in civilian centers managing low-velocity penetrating neck trauma.[23]

Initially missed cervical injuries secondary to neck trauma result in a mortality rate of greater than 15%.  Exsanguination accounts for up to 50% of the mortality from penetrating neck injuries.[21] Ten percent of neck wounds lead to respiratory compromise. Loss of the airway patency may occur precipitously, resulting in mortality rates as high as 33%.

Overall, the mortality rate for civilian wounds secondary to penetrating neck trauma is 2-6%. However, injury to a major blood vessel results in fatality almost 65% of the time, including prehospital deaths.

Soft tissue cervical strains and sprains, commonly known as whiplash injuries, initially may be associated with minimal pain. Subsequent edema and medicolegal considerations may cause worsening of symptoms over the ensuing 24-48 hours. Instruct the patient that complete resolution of symptoms may require 2-12 weeks. Stress the importance of follow-up care.

Recommendations regarding the use of alternativee modalities (eg, cold, heat, manipulation, massage) depend on what works best for the patient. Discourage the prolonged use of soft collars.

Patients who sustain superficial lacerations and are discharged should be supplied with adequate instructions for caring for wounds.

Because many critical organs and structures are at risk from neck trauma, clinical manifestations can vary greatly. The presence or absence of symptoms can be misleading, serving as a poor predictor of underlying damage. For example, only 10% of patients with blunt vascular damage develop symptoms in the first hour.

Use all available sources when trying to establish the mechanism of injury. Question the patient, involved bystanders, and prehospital personnel. Clarify events surrounding the traumatic event, establish the amount of time that elapsed since the injury, and confirm the patient's baseline condition. Determine the amount of blood that was lost at the scene, whether the patient lost consciousness, and if there is any evidence of recent drug or alcohol ingestion.

When neck trauma results from a motor vehicle crash, inquire about seat belt use, location of the patient in the car (driver or front or back seat passenger), deployment of an air bag, and magnitude of car damage (eg, intrusion, steering column and windshield intact or broken).

In the event of a penetrating trauma, try to verify details about the weapon used, such as type and size of knife or type and caliber of gun. For patients with injuries due to hanging, try to determine the suspension time (when the patient was last seen), drop height, ligature used, history of alcohol or drug abuse, and history of suicide attempts.

Characterize pain (eg, location, nature, intensity, onset, radiation), and document the nature and location of all stated injuries. Cardiovascular manifestations range from bleeding to symptoms normally associated with a cerebrovascular accident. Symptoms relating to the aerodigestive tract include dyspnea, hoarseness, dysphonia, and dysphagia. CNS problems include paresthesias, weakness, plegia, and paresis.

A standard approach to the patient with neck trauma is advised. The primary survey should consist of determination of airway patency, breathing, and adequacy of circulation. Keep in mind that loss of patency of the airway may occur precipitously. The patient should be fully exposed and any disabilities noted.

On secondary survey, the neck should be methodically examined, searching for clues that indicate damage to vital contents. The sensitivity of the physical examination to identify all significant neck damage remains controversial. Some experts in the field of trauma assert that physical examination alone is sufficient to assess zone II for injury, while others believe that diagnostic testing is mandatory.

A single examination is not sufficient, because the onset of signs of injury may be delayed and progressive with neck trauma. Carefully inspect the neck for a breach of the platysma. Invested by the most superficial fascia, violation of the platysma serves as a marker for possible serious penetrating neck wounds. Any violation of the platysmal muscle should be an alert to the potential for grave damage to the contents of the neck. If the platysma is violated, determine whether the wound lies anterior (anterior triangle) or posterior (posterior triangle) to the sternocleidomastoid muscle, and determine in what zone the injury is found. Try to specify the direction of the wound tract (eg, toward or away from the midline or clavicle). About 50% of cases of penetrating neck trauma in which the platysma is violated have no further injury. If the platysma is clearly not violated by a penetrating injury, the patient can be safely cleared of a significant underlying injury.

Consider an arterial injury of the neck in patients manifesting any degree of gross bleeding or presence of a hematoma. Hard signs of an arterial injury include a large expanding hematoma, severe active or pulsatile bleeding, shock unresponsive to fluids, signs of cerebral infarction, presence of a bruit or thrill, and diminished distal pulses. Virtually all patients with hard signs of an arterial injury require operative repair.

Soft signs, such as a nonexpanding hematoma and paresthesias, do not improve the predictive value of an arterial injury more than indicating the proximity of the wound to a major vessel.

The presence of a pulse does not exclude a vascular injury, and absence of a pulse is not diagnostic of vascular damage. Clinical findings are lacking initially in almost one third of patients with an arterial injury of the neck. Nearly one third of carotid artery injuries are associated with a central neurologic deficit.

Unnecessary probing or manipulation of the wound or performing any action that may cause the patient to gag, choke, or cough is discouraged. Any of these reactions may dislodge a clot and provoke a life-threatening hemorrhage.

Perforation of the pharynx or the esophagus following blunt neck trauma occurs infrequently (present in approximately 10% of trauma admissions). Initially, the patient may have no complaints, with the physical examination often failing to reveal any injury. Indirect signs of aerodigestive injuries include hematemesis, odynophagia, subcutaneous emphysema, and blood in the saliva or in the aspirate of a nasogastric tube. Because the esophagus lacks a serosa layer, it is more susceptible to iatrogenic injury such as following endoscopy, passage of a nasogastric tube, or inadvertent esophageal intubation. Esophageal perforation is the most serious and rapidly fatal trauma-induced perforation of the GI tract.

Examine the patient who has been strangulated. Note location and depth of marks, petechial hemorrhages of the skin and subconjunctival tissue (Tardieu spots), noisy or impaired respiration or phonation (eg, stridor, hoarseness, poor air movement), and palpable crepitus or tenderness over the larynx and trachea. Check for neurological deficits.

Signs of spinal cord or brachial plexus injury

Brachial plexus injuries sustained from blunt trauma tend to involve the upper nerve roots (C5-C7), diminishing the capacity of the upper arm while sparing strength and sensation of the lower arm.[24]  A radical avulsion of the brachial plexus results in a flaccid, numb extremity.

Quadriplegia occurring with complete transection of the spinal cord manifests as an absence of all motor, sensory, and reflex function below the level of injury. Bilateral neurologic findings imply a spinal cord injury until proven differently.

Pathologic reflexes, such as the Babinski reflex (extension of big toe) and Hoffmann sign (overactive muscle-stretch reflex), may be present.

Brown-Séquard syndrome results from hemisection of the spinal cord, causing ipsilateral motor paralysis with contralateral sensory deficits.

Priapism and loss of the bulbocavernous reflex may occur, and rectal tone may be poor.

Urinary retention, fecal incontinence, and paralytic ileus can occur from spinal cord damage.

Horner syndrome (ipsilateral miosis, enophthalmos, anhidrosis) results from disturbances of the stellate ganglion.

Neurogenic shock is a diagnosis of exclusion and is characterized by persistent bradycardia despite hypotension.

Hypoxia and hypoventilation can follow disruption of phrenic innervation to the diaphragm.

Signs of larynx or trachea injury

Signs of a laryngeal or tracheal injury include the following[7] :

• Voice alteration

• Hemoptysis

• Stridor

• Drooling

• Sucking, hissing, or air frothing or bubbling through the neck wound (It may be provoked by coughing.)

• Subcutaneous emphysema and/or crepitus

• Hoarseness

• Dyspnea

• Distortion of the normal anatomic appearance (eg, loss of normal landmarks, asymmetry, flattened thyroid prominence, tracheal deviation)

• Pain on palpation or with coughing or swallowing

• Pain with tongue movement implies injury to the epiglottis, hyoid bone, or laryngeal cartilage

• Crepitus (this hallmark sign of disruption to aerodigestive tract is noteworthy in only one third of cases)

Signs of penetrating injuries of the heart, aorta, and great vessels

Signs of penetrating injuries include the following:

• Hemorrhage, usually associated with large wounds (eg, gunshot wounds [GSWs])

• Massive hemothorax

• Hypotension

• Tamponade (if intrapericardial portion of aorta is injured)

• Weak or absent carotid or brachial pulse

• Paradoxical pulse (decrease in systolic BP with inspiration)

• Bruit

• Cervical or supraclavicular hematoma

• Bleeding from the entrance wound

• Upper extremity ischemia

• Coma

• Hemiparesis

• Respiratory distress secondary to tracheal compression

Signs of tracheobronchial or lung injury

Signs of tracheobronchial/lung injury include the following:

• Subcutaneous emphysema

• Cough

• Respiratory distress

• Hemoptysis, usually secondary to a disrupted bronchial artery

• Tension pneumothorax

• Continuous air leak persisting after chest tube insertion

• Mediastinal crunch (Hamman crunch)

• Intercostal retractions

• Decreased breath sounds

• Hyperresonance to percussion of the contralateral hemithorax, associated with hyperinflation of the unaffected lung

• Tachypnea

• Agitation

• Hypotension

• Tachycardia

• Hypoxia

• Shifting of the trachea and the apical heartbeat away from the injured side

Signs of carotid artery injury

The following are signs of a carotid artery injury:

• Decreased level of consciousness

• Contralateral hemiparesis

• Hemorrhage

• Hematoma

• Dyspnea secondary to compression of the trachea

• Thrill

• Bruit

• Pulse deficit

Signs of jugular vein injury

Signs of injury to the jugular vein include the following:

• Hematoma

• External hemorrhage

• Hypotension

Signs of cranial nerve injuries

Signs of cranial nerve injuries include the following:

• Facial nerve (cranial nerve VII) - Drooping of the corner of the mouth

• Glossopharyngeal nerve (cranial nerve IX) - Dysphagia (altered gag reflex)

• Vagus nerve (cranial nerve X, recurrent laryngeal) - Hoarseness (weak voice)

• Spinal accessory nerve (cranial nerve XI) - Inability to shrug a shoulder and to laterally rotate the chin to the opposite shoulder

• Hypoglossal nerve (cranial nerve XII) - Deviation of the tongue with protrusion

• Thoracic duct injury: This is usually asymptomatic and tends to be an incidental finding during surgical exploration.

Signs of esophagus and pharyngeal injury

The following signs suggest esophageal or pharyngeal injury:

• Dysphagia

• Bloody saliva

• Sucking neck wound

• Bloody nasogastric aspirate

• Pain and tenderness in the neck

• Resistance of neck with passive motion testing

• Crepitus

• Bleeding from the mouth or nasogastric tube

For any patient thought to have a neck injury, obtain the standard trauma blood studies (CBC count, electrolytes, other warranted blood chemistry levels, blood type and crossmatching).

Generally, a CBC count and blood typing suffice in a previously healthy individual, but patients with comorbid disease or those in shock may require additional studies, including a determination of coagulation profiles.

Obtain alcohol and toxicology screens, when indicated.

Any imaging study is associated with delay, and transport to the operating room should not be delayed when the patient's condition warrants emergent surgery. Determining the specific study and order of testing depends on institutional preferences, mechanism of injury, and the clinical scenario. Detection of pharyngoesophageal injuries poses many problems, requiring a high index of suspicion. The failure to diagnose these injuries can lead to significant morbidity and mortality.[11, 15, 25, 26]

Cervical radiography

Unless indicated otherwise, most patients who have sustained significant injury to the neck require plain-film radiography.[25] Although not helpful in most cases of vascular or related soft tissue injury to the neck, anteroposterior (AP) and lateral films may help localize a foreign body. However, in many trauma centers, helical CT scans are supplanting plain cervical films for all patients with significant neck injuries.

Review the cervical radiographs for emphysema, fractures, displacement of the trachea, and presence of a foreign body (eg, missile fragments).

Chest radiography

Any finding suggestive of a zone I wound or damage to the thoracic cavity mandates obtaining a chest radiograph.

Circumspectly review the film for hemothorax, pneumothorax, widened mediastinum, mediastinal emphysema, apical pleural hematoma, and foreign bodies.

Open injuries bring the greatest risk of foreign body contamination. Commonly encountered materials include gravel debris, glass fragments, wooden splinters, and metal particles. Foreign body presence is obvious in some injury patterns, but others may not suggest contamination with foreign body materials. Foreign objects that have not been detected and removed introduce risk of severe wound infections and chronic wound healing disorders. Besides these severe health issues, medicolegal consequences should be considered. Although accurate clinical examination is the first step for the detection of foreign body materials, choosing the appropriate radiologic imaging is decisive for detection or non-detection of foreign material. When impaired wound healing continues over time, the presence of an undetected foreign object must be considered.[27]

Supplementary tests

Obtain supplementary tests in the stable patient if specific system injuries are suggested by the history, physical, or prior ancillary studies. Additional imaging studies include CT, MRI, color flow Doppler studies, contrast studies of the esophagus, interventional angiography, and endoscopic images.

CT scans prove most useful when bony or soft tissue damage is a consideration. Requesting a CT scan of the neck when a laryngeal fracture is suspected is especially important because clinically subtle injuries of the larynx often escape detection but become readily identifiable on CT scan.

Although conventional angiography remains the criterion standard for evaluation of vascular trauma in the neck, CT angiography (CTA) offers advantages.[15, 26] CTA is readily accessible in most centers, can be rapidly performed, and causes fewer complications. Additionally, some experts assert that subtle disruptions of the vessel wall that are difficult, if not impossible, to detect on angiography (if they are not prominent enough to alter the contrast column) may be detected on CTA through planar reconstruction.[28, 29, 30, 31, 32, 33]

Penetrating neck injury can have potentially devastating consequences because many vital structures are contained within the neck. In patients who do not require immediate surgery, CTA of the neck is the test of choice for characterizing the injury. A systematic approach to assessment will ensure thorough evaluation and give the reporting radiologist the best chance of identifying significant findings, which can often be subtle. Clear communication with the trauma team is needed at the time of the request and after imaging has been evaluated; relaying significant findings to the team is vital for ensuring the best patient outcomes.[34]

CTA alone may not be sufficient to exclude esophageal injuries in penetrating neck trauma. Because delayed diagnosis is associated with increased morbidity, additional diagnostic interventions should be undertaken if the clinician is concerned about esophageal injury.[35]

In addition to providing visualization of traumatic vascular lesions such as partial or complete occlusion, pseudoaneurysm, dissection, intimal flaps, and traumatic arteriovenous (AV) fistulas, CTA additionally provides useful information about the cervical soft tissues, aerodigestive tract, spinal canal, and spinal cord. Artifacts secondary to metal, specifically bullet fragments, which can obscure vascular detail, can limit CTA. Likewise, shoulder artifacts may limit diagnostic information from CTA. In these cases, angiography is necessary for optimal assessment.[28, 36, 37]

In 23 patients with penetrating injury and hard signs, the addition of CTA to the management of hemodynamically stable patients significantly decreased the rate of negative neck explorations without increasing missed injury rate. Sensitivity, specificity, positive predictive value, and negative predictive value for CTA in the presence of hard signs were found to be 83%, 100%, 100%, and 94%, respectively.[29]

Consider an emergent MRI and/or magnetic resonance angiography for evaluation of the patient exhibiting neurologic impairment with minimal or absent abnormalities on plain radiographs of the cervical spine.

Some institutions now substitute color flow Doppler ultrasonography or use it as a screening test in low-risk patients or those thought to have a carotid injury. However, its sensitivity remains variable (especially with zone I and zone III injuries), and its use is controversial.

Duplex ultrasonography can be obtained in stable patients. However, this noninvasive and relatively inexpensive modality is operator-dependent. In addition, non-occlusive injuries may be missed if flow is preserved, as occurs with intimal flaps and pseudoaneurysms. The role of this imaging approach is limited in zone III evaluation.[3]

Although a normal Gastrografin study occasionally proves useful in the evaluation of the cervical esophagus, it does not rule out a pharyngoesophageal leak. Deciding which contrast agent to use when studying the esophagus remains a subject of dispute among the experts. Advocates for Gastrografin use note that it is less likely than barium to cause an inflammatory response if extravasation through a breach occurs. However, barium induces less inflammation in the lungs; therefore, it poses less of a risk in the patient predisposed to aspiration.

Esophagography should be performed if an esophageal perforation is suspected.[3]

Endoscopy

Laryngoscopy, bronchoscopy, pharyngoscopy, and esophagoscopy may be useful in the assessment of the aerodigestive tract. Rigid endoscopes are superior to flexible scopes.

Before inserting any scope, confirm that the airway is patent, intact, and protected (usually ensured by placement of an endotracheal tube). Ecchymosis of the posterior or lateral pharyngeal wall implies concealed neck damage.

Endoscopy, especially indirect laryngoscopy, often becomes problematic in the apprehensive trauma patient, and it may be best to defer examination until the airway is protected and the patient is anesthetized.

Angiography

Angiography routinely is used to evaluate stable patients sustaining penetrating wounds to zones I and III that pierce the platysma. Angiography remains preferred over alternative contrast studies because angiography is less likely to obscure vascular damage.

A 4-vessel study is a prerequisite.

Preoperative arteriograms facilitate operative decision making, particularly when a question of intrathoracic involvement exists (such as with zone I injuries necessitating a thoracotomy). Otherwise, consider confirming adequacy of the collateral circulation if carotid artery ligation is contemplated (as may be necessary in zone III arterial wounds).

Occasionally, surgical exposure and access to bleeding vessels proves challenging, if not unattainable or impractical, and selecting therapeutic embolization or occlusion of the harmed vasculature remains a better option. This is achieved by placing an intravascular balloon tip catheter or shunt. However, discretion is critical because forceful placement of a catheter or shunt may dislodge a clot (eg, causing a stroke) or may risk causing or exacerbating intimal damage, and even risk inauspicious perforation of the blood vessel.

Drawbacks include cost and the inherent danger of any vascular, particularly arterial, invasive procedure.

In most urban settings, immediate transport of the patient with neck trauma to the closest level I trauma setting is most appropriate because state-of-the-art care frequently necessitates a multidisciplinary approach. Emergency medical personnel should restrict intubation attempts except when anticipating a prolonged transport time; when the patient is apneic, pulseless, or moribund; or when respiratory arrest is imminent.

Providing supplemental oxygen and clearing the airway of all secretions and foreign bodies, including unfastened dentures and loose teeth, frequently prove sufficient, practical, and helpful for the conscious patient. Injudicious attempts to vigorously insert an endotracheal tube may worsen the patient's state by running the risk of utterly marring the airway. Ventilation of the patient with a positive-pressure bag-valve-mask device can exacerbate underlying subcutaneous emphysema, conceivably distorting the airway anatomy and impairing breathing and circulation.

Impregnated gauze should be used to cover sucking neck wounds or lacerations exuding bubbling air.

Patients who sustain significant blunt trauma require cervical spine precautions, including cervical spine immobilization and supine placement of the patient on a backboard. However, based on retrospective studies, the incidence of cervical spine injuries in patients sustaining penetrating neck injuries who are alert, oriented, and lack any focal neurologic findings is very low.[38, 39] In addition, a cervical collar could potentially obscure an expanding neck hematoma.

Defer removal of helmets or other headgear until neck stabilization has been ensured.

Bleeding from the neck is best controlled with direct pressure. Impaled objects should not be extracted in the field. Intravenous access should be established en route to the hospital. The access should be preferably placed in the extremity opposite the side of the injury in case disruption of the ipsilateral venous circulation has occurred.

Emergency medical reports should relate the mechanism of injury, including the type of weapon involved, estimated amount of blood lost (EBL) at the scene, initial vital signs, noteworthy physical findings, and total transport time.

Initial evaluation and stabilization includes securing the airway, controlling bleeding, providing cervical spine precautions, and identifying life-threatening conditions. Most blunt traumatic neck injuries can be managed nonoperatively. Surgical assessment of penetrating neck wounds usually requires a greater resolve for operative intervention, although prior axioms decreeing surgery as the only option are no longer as absolute.[40] However, when an injury violates the platysma, it is sensible and prudent to engage a qualified surgeon or to transfer a stable patient to a trauma center where such care is available.[15, 41, 42]

Ensure compliance with EMTALA regulations. Transfers from nontrauma centers to trauma centers are considered "medically indicated" transfers because the purpose of each transfer is to obtain the higher level of care necessary to treat a patient's condition.

Airway

Emergency department care of the patient with neck trauma commences with assessment and stabilization of the ABCs, starting with the airway. Unfortunately, the same conditions that compel active airway management also intensify the obstacles to achieving successful intubation. Nonetheless, a wait-and-see attitude merely invites disaster.

Consequently, a preplanned strategy based on the expertise of the available staff, equipment at hand, the patient's clinical condition, and the determined necessity for further testing should be in place before this scenario occurs. An entrenched partnership must exist between all potentially involved departments, especially emergency medicine, surgery, and anesthesiology.

Intubating a patient with penetrating neck trauma may incite gagging or coughing, potentially dislodging a clot and setting off massive bleeding from a previously injured blood vessel. Additionally, existent bleeding and edema rapidly distort the surrounding anatomy, making oral intubation difficult, if not impossible. Nevertheless, assessment of the airway takes priority over all other actions, including those procedures that risk exacerbating hemorrhage. Early preparation by the practitioners treating the patient is crucial. This includes ensuring ease of access to an acceptable suction apparatus and having multiple-sized endotracheal tubes. as well as any tools and supplies necessary to perform the surgical airway procedure, close at hand.

Before intubation, clear the mouth of foreign debris with the fingers or manual suction. Remedy partial airway occlusion originating from the tongue by performing a modified jaw thrust. Never do a head-tilt chin-lift maneuver in a patient with a suspected cervical spine injury.

Perform emergent orotracheal intubation in patients displaying signs of acute or impending respiratory distress, such as perceptible noisy breathing; an inability to suitably handle blood, vomitus, or other bodily secretions; and obvious distortion of any neck landmarks, particularly tracheal deviation or existence of massive subcutaneous air. The choice of technique depends on the expertise of the attending staff and the capability to perform a surgical airway procedure. Despite concerns about converting a partially obstructed airway into a completely obstructed airway, a retrospective series by Mandavia et al proved rapid sequence intubation to be safe and effective when performed by emergency physicians trained in this skill.[43]

An awareness of potential laryngeal damage is imperative prior to intubation, even when the airway must be emergently secured. A neck hematoma can obscure landmarks, in addition to causing the danger of precipitating life-threatening exsanguination. Overwhelming suspicion for laryngeal injury directs execution of a surgical airway procedure to avoid injudicious endeavors at oral intubation that could sever a tenuously attached trachea or larynx, conceivably causing a catastrophe consequent to complete loss of the airway if the larynx detaches and dislodges into the chest.

Several large case series such as that by Shatney et al[44] demonstrate the safety of oral intubation with cervical in-line stabilization, provided that direct laryngoscopy and intubation are performed in a gentle, atraumatic manner and explicit cervical spine immobilization is maintained. This is the preferred approach for the accomplished intubator in the patient with blunt trauma with suspected cervical spine injury.

Alternative techniques for securing the airway include fiberoptic intubation, gum elastic bougie, percutaneous transtracheal intubation, and wire-guided retrograde intubation.

Fiberoptic intubation is a sensible course of action, especially for patients thought to have sustained a cervical spine injury or who exhibit gross distortion of the airway. Limitations include clinician inexperience, lack of necessary equipment, and copious bleeding or secretions. Percutaneous transtracheal intubation, also referred to as translaryngeal ventilation, is a quick and relatively simple technique in which a needle is inserted through the cricothyroid membrane and attached via a Y connector to an oxygen supply of at least 50 psi. This procedure is contraindicated when transection of the trachea or damage to the cricoid cartilage or the larynx is strongly suspected. Barotrauma may occur with percutaneous ventilation. Retrograde tracheal intubation is an invasive procedure that may be suitable when excessive amounts of blood or secretions preclude fiberoptic intubation or when neck movement must be restricted.

Breathing

Signs or symptoms of respiratory embarrassment compel consideration for a hemothorax or a pneumothorax. Zone I injuries may breach the chest cavity. Ventilatory distress that persists beyond competent intubation indicates a possible tension pneumothorax, which requires needle decompression and chest tube placement. Occlusion of the tracheobronchial tree, whether due to a foreign body or iatrogenic, is another cause of ventilatory problems.

Circulation

Bleeding that originates from neck trauma should be controlled by direct pressure. Do not blindly clamp a transected vessel, because inadvertent injury to adjacent structures or extension of blood vessel damage may occur. Never probe, cannulate, or locally explore these wounds in the ED, because these actions may cause an air embolus or dislodge a clot and provoke bleeding.

Do not remove objects protruding from the neck in the ED.

Concurrent with checking bleeding, establish intravenous access with at least 2 large-bore catheters (14 or 16 gauge). If injury to the brachiocephalic or subclavian vein is a possibility, place 1 intravenous access site in a lower extremity site and another access site in the upper extremity on the uninjured side.

Placing the patient in a mild Trendelenburg position to decrease the risk of air embolization may be advantageous.

In selected cases, bleeding that cannot be controlled or reached with direct pressure may benefit from balloon tamponade. Insert a Foley catheter into the wound. Direct it toward the site of bleeding, and inflate the balloon until bleeding resolves or moderate resistance is noted. As an example, for zone I injuries, slide in a Foley catheter toward the pleural cavity, and then inflate the balloon with sterile saline and retract it, striving to compress the injured subclavian vessel against the first rib or clavicle.[21]

On rare occasions, such as with wounds in the pharynx, applying direct pressure to wounds may be impractical. These wounds may necessitate a cricothyroidotomy with subsequent packing of the pharynx as a temporary strategy.

Disability

Blunt neck trauma causes a wide spectrum of injuries ranging from a minor contusion or abrasion to life-threatening scenarios. Cervical spine injury remains a continual concern, especially for patients sustaining significant blunt trauma to the head and/or neck.

Not only is the spinal cord vulnerable to injury, but other neural pathways are as well, such as the phrenic, recurrent laryngeal, and lower lying cranial nerves, along with the brachial plexus. Additionally, detection of a neurologic deficit may signify damage to the carotid or vertebral artery with subsequent CNS ischemia.

Exposure

To view the anterior part of a neck that is concealed by a cervical collar, appoint an assistant to maintain the neck in a neutral position, and then remove the anterior aspect of the collar and proceed with the evaluation.

Expose and observe the patient's entire body to avoid overlooking other potentially lethal injuries.

Miscellaneous

Once the patient is considered somewhat stable, the next step is to gently evaluate the neck wound to determine if the platysma has been violated. In this regard, the platysma is treated like the peritoneum of the abdomen; if it is violated, involvement of a qualified surgeon is mandatory. Even the most innocuous-appearing wound of the neck should not be probed or locally explored in the ED once a breach in the platysma is confirmed, because a real risk of provoking clot dislodgment with subsequent secondary hemorrhage exists.

If there are no findings necessitating emergent surgeries, confer with a qualified trauma surgeon about further ED evaluation.

If the condition of a patient with penetrating neck trauma deteriorates to a state of cardiopulmonary arrest and the facility and the staff are qualified, perform an emergent thoracotomy to gain better control of the bleeding.

Consider cross-clamping the aorta and aspirating the right ventricle to forestall advancement of an air embolus.

It is usually best to avoid inserting a nasogastric tube until the airway is secured.

Despite the availability of advanced medical imaging techniques, foreign body detection remains a challenge, as it is dependent on the foreign body material, the affected anatomic site, and the severity of the injury. Therefore, obtaining a detailed history of the circumstances leading to trauma is essential when foreign objects are not visible during clinical examination. Precise detection of the foreign body, determination of its anatomic position, and evaluation of its effects on surrounding structures are vital, especially when impalement injuries of the head and neck area are managed. An interdisciplinary planning approach is essential prior to removal of the foreign object. Finally, tension-free anatomic adaptation of corresponding structures is crucial for maintaining and restoring aesthetics and function.[45]

Consult an experienced trauma surgeon emergently once platysmal violation is confirmed. Additional consultants should be prioritized with guidance from the trauma surgeon who will oversee the patient's care.

Ordinarily, urgent surgical exploration of a penetrating wound to the neck is indicated for the following:

• Continued blood loss, expanding hematoma, hypovolemic shock, and/or pulse deficit

• Airway obstruction, impending airway obstruction, open trachea, and/or air bubbling from the wound site

• Neurologic deficit

• Blood in the aerodigestive tract, hemoptysis, and/or hematemesis

• New-onset bruit

Observe patients with all but the most trivial of neck wounds for delayed onset of symptoms. Platysma violation usually justifies admission for 24 hours of observation to avoid missing occult injuries, particularly vascular and esophageal wounds. Decisions regarding the need to admit a patient with blunt neck trauma are based on the presence or absence of signs and symptoms, as well as the patient's underlying physiologic status and factors such as the availability of care, extent of care warranted, and willingness of responsible parties to participate.

Many patients are discharged with the diagnosis of whiplash injury, which is neck pain following sudden flexion-extension of the head (eg, with a rear-end motor vehicle accident). By definition, whiplash injury implies that bony damage or other significant injuries are excluded. In addition, the pain originates from a stretching and bruising of the neighboring musculature and supporting ligaments.

Lacerations that are superficial to the platysma in an otherwise asymptomatic patient should be managed in the same way as cuts found elsewhere on the body. Clean lacerations may be sutured as late as 12-18 hours after injury, since the neck is ordinarily exceptionally well perfused.

Standing protocols dictating the treatment of patients with neck trauma must be in place. Such guidelines should indicate which patients require emergent surgery, transfer, or further workup.

A major disadvantage of exploring all penetrating neck injuries with platysma violation is a nontherapeutic exploration in approximately 50% of cases. This results in unnecessary costs and nonessential invasive procedures. Studies (eg, those by Demetriades et al[46] and Ngakane et al[47] ) suggest that the majority of patients with penetrating neck trauma can be treated nonoperatively. No definitive recommendation exists, and treatment protocols should be based on a multidisciplinary agreement within the institution. However, because of the prospect of occult injuries with zone I and III wounds, a relatively aggressive workup is warranted. The definitive evaluation and management of penetrating trauma in particular continues to evolve.

Decisions regarding whether to ligate or repair arterial injuries rely on the presence or absence of a major neurologic deficit (coma and/or paralysis); some surgeons prefer to avoid the danger of reperfusion injury of the brain.

Embolization may halt bleeding from a damaged vessel in the neck. If the patient's vital signs are not stabilized, death in the radiologic suite is a real risk. Temporary occlusion of the blood vessel may be achieved by insertion of a gelatin sponge or coil.

Airway obstruction may result from evolving tracheal and/or laryngeal edema or stenosis. Vocal cord paralysis and voice change also may follow laryngeal trauma.

Swallowing dysfunctions may affect patients with neck trauma. Aspiration of material (eg, blood, vomitus) is always a possibility. Patients who survive the initial strangulation injury may succumb to pulmonary edema or bronchopneumonia.

Unrecognized vascular injury may lead to delayed exsanguination (rupture of clot with hemorrhage), clot embolization or thrombosis, and/or formation of a false channel (pseudoaneurysm) or arteriovenous fistula (both of which can evolve into delayed hemorrhage). Vascular injuries subsequent to blunt trauma specifically are associated with a high complication rate. Approximately 10% of patients are asymptomatic in the first hour.

Soft tissue necrotizing infections caused by mixed bacterial organisms may originate from contamination of the neck or extravasation from oral wounds. Sepsis, mediastinitis, and cervical osteomyelitis may occur.

Fistulas include tract formation between the trachea and the innominate arteries (tracheoinnominate [TI] fistula), the trachea and the brachiocephalic artery (potential for a catastrophic hemorrhage within the tracheobronchial tree), and the esophagus and the skin (esophagocutaneous fistula).

Complications associated with arteriography range from arterial wall injuries (eg, intimal flaps, thrombosis, severe vascular spasm) to neurologic impairment, anaphylactic reaction, and groin hematoma (may lead to femoral artery occlusion).

Air embolism is an infrequent, seldom-mentioned complication that arises from tears in the major neck veins. Penetrating neck trauma may precipitate an air embolism. Depending on where the embolus settles, positioning the patient may lessen the chance of embolus propagation. Suspect this entity in patients developing unexpected hypotension and/or arrhythmia, especially in the setting of an increase in central venous pressure.

Lead intoxication is an unusual problem that occurs subsequent to a bullet remaining lodged in the neck, usually in a joint space. Warning signs and symptoms include abdominal pain, nephropathy, and unexplained anemia.

Zone I wounds are often associated with thoracic injury causing a pneumothorax, hemothorax, or tension pneumothorax.

The American College of Radiology (ACR) has published the following recommendations[48] :

• In patients with clinical soft injury signs and in patients with hard signs of injury who do not require immediate surgical exploration, computed tomographic angiography (CTA) of the neck is the preferred imaging procedure to evaluate the extent of injury.
• When there remains clinical concern for vascular injury despite a normal or equivocal CTA of the neck, catheter-based arteriography is useful for further evaluation.
• The benefit of arteriography is the ability to perform, in tandem, an endovascular procedure if needed.
• If there remains a concern for aerodigestive injury despite a normal or equivocal CTA of the neck, an x-ray single contrast esophagram may be considered, but it should be used in conjunction with direct visualization techniques. 
• MRI, in particular fat-suppressed T2-weighted imaging, is more sensitive than CT or CTA for assessing potential cartilaginous and fibrous injuries but is relegated to specific problem-solving cases and is not routinely performed.

Western Trauma Association guidelines for neck trauma include the following[49] :

• Initial management of patients with penetrating neck injury, which violates the platysma, should follow the advanced trauma life support guidelines.

• Patients who during their primary survey demonstrate "hard signs" or hemodynamic instability require expeditious transfer to the operating room delayed only by securing an unstable airway, with a surgical airway if attempts at oral-tracheal intubation are unsuccessful, and attempting tamponade of active bleeding while en route.

• Most penetrating neck injuries can be approached via an anterior sternocleidomastoid incision.

• Zone I neck injuries may require a median sternotomy with extension to an anterior sternocleidomastoid incision or supraclavicular incision with or without clavicular head resection.

• For zone II transcervical injuries, a transverse cervical collar incision may provide access to both sides of the neck, with the potential to extend along the anterior sternocleidomastoid muscle.

• Zone III represents a difficult anatomic zone of injury for distal vascular control. At times, subluxation, dislocation, or resection of the mandible may be necessary to gain operative vascular control.

• Patients without indications for mandatory neck exploration who remain hemodynamically stable can be managed expectantly with observation/serial examinations or undergo further radiographic evaluation, depending on the level of suspicion for injury, the symptoms demonstrated by the patient, and the anatomic zone of injury.

• Zone I patients without indications for neck exploration should undergo CTA of the chest and neck to evaluate for both vascular and aerodigestive injuries.

• In hemodynamically stable patients with CTA evidence of zone I injury, further intervention is typically required. Successful endovascular approaches for arterial injuries using covered stents for zone I injuries have been documented.

• Hemodynamically stable patients with documented zone I aerodigestive injury by CTA should undergo prompt operative intervention in most cases because this is associated with better outcome.

• Patients with symptomatic zone II injuries should undergo early operative neck exploration by either the standard anterior sternocleidomastoid incision or cervical collar incision, depending on the nature of the injury.

• In hemodynamically stable patients with CTA evidence of zone II injury, operative intervention is typically required because access is simple and repairs are definitive.

• Hemodynamically stable zone III patients with suspicion for injury should undergo CTA of the neck and head to evaluate for vascular and aerodigestive injuries.

Infection subsequent to penetrating wounds of the neck is a major cause of death and disability. Administering prophylactic antibiotics, while not decisively validated by scientific studies, should be a consideration. Recommended medications vary from penicillin to those with broad-spectrum coverage. Factors to consider include the physical nature of the injury (eg, simple laceration vs blunt trauma with tearing-type injuries). If prophylactic antibiotics are to be effective, attempt to obtain adequate tissue levels immediately, preferably within 4 hours of injury.

Other therapeutic agents to consider are the corticosteroids. Massive doses of steroids are believed to have possible benefit in improving neurologic function in selected subsets of patients. In the second phase of a benchmark study, patients who had sustained blunt spinal injury within a 12-hour time frame were given a 30 mg/kg intravenous (IV) bolus of corticosteroids followed by 5.4 mg/kg/hr for 23 hours. Overall, patients who appropriately received steroids within 8 hours revealed slight improvement in motor and sensory function at 6 months. Other experimental agents include naloxone, dimethylsulfoxide, and growth factors. Spinal cooling also has been proposed.

Drugs that facilitate endotracheal intubation, especially those used for rapid sequence intubation, should be readily available.

Class Summary

Therapy must cover all likely pathogens in the context of the clinical setting.

Cefotetan (Cefotan)

Second-generation cephalosporin indicated for infections caused by susceptible gram-positive cocci and gram-negative rods.

Dosage and route of administration depends on condition of patient, severity of infection, and susceptibility of causative organism.

Gentamicin (Garamycin)

Aminoglycoside antibiotic for gram-negative coverage. Used in combination with both an agent against gram-positive organisms and one that covers anaerobes. Not the DOC. Consider if penicillins or other less toxic drugs are contraindicated, when clinically indicated, and in mixed infections caused by susceptible staphylococci and gram-negative organisms.

Ampicillin (Omnipen)

Bactericidal activity against susceptible organisms. Alternative to amoxicillin when patient unable to take medication orally.

Clindamycin (Cleocin)

Lincosamide for treatment of serious skin and soft tissue staphylococcal infections. Also effective against aerobic and anaerobic streptococci (except enterococci). Inhibits bacterial growth, possibly by blocking dissociation of peptidyl t-tRNA from ribosomes causing RNA-dependent protein synthesis to arrest.

Ceftriaxone (Rocephin)

Third-generation cephalosporin with broad-spectrum, gram-negative activity; lower efficacy against gram-positive organisms; higher efficacy against resistant organisms. Arrests bacterial growth by binding to one or more penicillin-binding proteins.