Neck Injury: Symptoms, Diagnosis, and Treatment.

Introduction

The neck is protected from the back by the spine, head upwards, and chest downwards. Therefore, the front and side regions of the neck are most exposed to trauma. In addition, there can be lacerations of blood vessels during neck trauma. Neck trauma can be blunt, penetrating, or a combination of both. The neck contains vital structures if injured and can lead to the individual's death.

How to Know if a Neck Injury Is Serious?

The severity of the injury depends on the zone of the neck involved in the trauma. For diagnostic and management implications, the neck has been divided into three zones-

• Zone Ⅰ - The area between the clavicle and the cricoid cartilage. The clavicle is the collarbone, and the cricoid cartilage is ring-shaped in the windpipe. It has essential structures like the origin of the carotid artery, the vertebral artery, the brachial plexus, the trachea, the esophagus, etc. It is challenging to explore injuries in this area because of the clavicle and bony structures of the thoracic inlet.

• Zone Ⅱ - This is the area between the cricoid cartilage and the angle of the mandible (lower jaw). The lower jaw is almost in the shape of an 'L.' The junction between the vertical and horizontal extension of the mandible is known as the angle of the mandible. The structures present in this zone are the carotid and the vertebral arteries, the internal jugular being, the trachea, the esophagus, etc. This zone is the largest of the three, frequently injured, and the easiest one to surgically explore in case of neck trauma.

• Zone Ⅲ - The area between the mandible's angle and the skull's base. It contains the distal carotid artery, vertebral arteries, and the pharynx (food pipe). Due to its closeness to the skull, this area is less feasible for examination and exploration. The severity of the neck injury also depends on the cause of the injury; different ways that can injure the neck are divided into three categories. They are-

• Blunt Trauma - Motor vehicle accidents and sports injuries come under this category; occasionally, the seatbelt can also cause trauma to the anterior portion of the neck. The critical point to notice in these injuries is the cervical spine injury, which often goes unnoticed during an examination.

• Penetrating Trauma - Gunshot and stab wounds will cause penetrating trauma to the neck. The extent of the injury depends on the violation of the platysma muscle. If the wound penetrates the platysma muscle, it is assumed severe and has damaged the vital structures.

• Strangulation or Near-Hanging - The neck contains the blood vessels that supply the brain. Excess external pressure applied to the neck will obstruct the blood flow to the brain, leading to cerebral hypoxia (reduced oxygen supply to the brain) and, if continued, will cause death due to asphyxiation (suffocation).

What Are the Symptoms of a Severe Neck Trauma?

All neck injuries should obtain a surgical consultation because, at times, the patient will not have any visible signs and symptoms and appear stable but will decompensate (loss of physiological and psychological function) rapidly as time progresses.

Decompensation happens due to injury to the vascular structures of the neck. Vascular injuries are common in neck trauma; they have a few hard signs which indicate the need for surgical intervention; the hard signs are-

• Shock.

• Visible bleeding.

• Difficulty in controlling bleeding.

• Airway compromise.

• Decreased or absent pulse.

• Audible bruit or palpable thrill. A thrill is a vibratory sensation felt on the injured skin indicative of a loud heart murmur caused by an incompetent heart valve.

• Stridor.

• Hoarseness in the voice.

• Pain during swallowing secretions.

• Neurological deficits include altered speech, hearing, and vision on physical examination.

Soft signs include minor hemoptysis (spitting of blood), hematemesis (vomiting of blood), dysphonia (abnormal voice), dysphagia (difficulty in swallowing), mediastinal emphysema (air between the lungs), and non-expanding hematoma.

Diagnostic investigations are done in stable patients if any soft signs are present; these will help identify additional injuries that can easily be overlooked. Unstable patients should be immediately transferred to the trauma center for assessment and emergency procedures, including surgery.

What Are the Investigations Done for Neck Injury?

If the patient is stable with soft signs, the following investigations are done for further assessment-

• Chest Radiography - This is done for patients with zone Ⅰ injury to look for pneumothorax (collapsed lung), hemothorax (blood in between the lungs), and pneumomediastinum (also called mediastinal emphysema).

• Computed Tomographic (CT) Angiography - Done to evaluate the extent of the vascular injury.

• Conventional Angiography - This is the gold standard for evaluating vascular injury. Four blood vessels- the carotid artery, vertebral vessels, the intracranial portion of the carotid artery, and the aortic arch are assessed in this procedure.

• Duplex Ultrasonography - Only limited to zone Ⅲ injuries in stable patients.

• Esophagography- Only done if an esophageal perforation is suspected.

The clinician will ask for any of the above investigations to identify additional injuries, but if the patient is unstable, a low threshold is maintained for further imaging studies.

How Are Severe Neck Injuries Treated?

Initial assessment should be done according to the advanced trauma life support (ATLS) protocols. Priority is always given to securing the airway and maintaining ventilation, followed by controlling bleeding and treating shock. Periodic examinations are part of the ongoing treatment; they guide the areas and the extent of the surgical exploration since there is no international consensus for managing severe neck injuries.

Managing severe neck injuries includes the following stages-

Airway Management

• If the airway is obstructed, but the anatomy of the respiratory system is preserved, rapid sequence intubation is done to secure the airway. It prevents pulmonary aspiration (accidental inhalation of objects or fluids) of gastric contents.

• Suppose the anatomy is distorted, but the patient is cooperative and can tolerate the procedure, in that case, tracheal intubation (placement of a tube into the windpipe) is done followed by fiberoptic laryngoscopy- a diagnostic test that uses a small telescope with light to support and determine the integrity of the airway.

• If the skeletal system collapses or there is significant structural airway disruption due to transection of the trachea, then tracheostomy (surgical opening of the trachea) will be necessary to maintain the airway. Tracheostomy is an opening surgically created through the neck into the windpipe (trachea) to facilitate breathing.

Surgical Exploration

• This depends on the physiological status and clinical findings after the examination. If the patient has hard signs of vascular injury, then external compression can be achieved with a Foley balloon catheter.

• A Foley catheter is introduced into the wound and then inflated like a balloon with 10 mL to 15 mL of water or until resistance is met. The catheter is clamped, and the neck wound is sutured up.

• This controls the bleeding temporarily and gives time to perform angiography to identify the source of bleeding before going ahead with emergency endovascular intervention. In a few patients, this step is sufficient to manage the vascular injury, thereby preventing other emergency surgeries.

• If the angiography indicates vascular injury, the patient will need a sternotomy (surgical opening of the breastbone) or thoracotomy (surgical opening of the thorax) to access the vascular structures. Suppose the injured blood vessel is a common or internal carotid artery. In that case, treatment includes repair of the artery with either transverse arteriography or a thin-walled polytetrafluoroethylene (PTFE) patch angioplasty. Both are surgical reconstruction procedures to repair a bleeding artery.

• If the patient is stable and without any hard signs, performing a multidetector helical computed tomography with angiography (MDCT-A) is advised to rule out any possible vascular, laryngotracheal, and pharyngoesophageal injuries. Patients with a stable MDCT-A will need routine evaluation to detect and treat delayed complications.

What Are the Complications of Surgery?

Complications that might happen after surgical exploration of neck injuries depend on a myriad of things; these include events surrounding the timing of the damage, associated medical conditions, expertise and availability of the vascular surgeon, etc.

The possible complications include airway obstruction, aspiration, vocal cord paralysis, perforated esophagus, necrotizing infection, stroke, air embolism, etc. It is often noticed that patients with zone Ⅰ neck injuries have the highest morbidity and mortality rate. If the injuries are sustained, the neurological deficits caused due to the injury will result in prolonged treatment.

Conclusion

Severe neck injuries require emergency treatment with the help of an interprofessional team. The prognosis of the treatment is always guarded; it is good in patients who retain neurological function but fatal in individuals who suffer from complete transection of the spinal cord. Prognosis also depends on the zone of the injury; out of all three, zone Ⅱ has the best prognosis because the injured vascular structures are readily accessible for surgical exploration. The outcomes and the quality of life of patients suffering from neck injuries can only be improved with continuous interprofessional care.