A 39-year-old man was brought to the ED by caretakers with a self-inflicted neck wound, thought to be caused by a kitchen knife. He has a history of schizophrenia, and complained of hoarseness. He denies chest pain, difficulty swallowing, focal neurological deficits, hemoptysis, or hematemesis. He is hemodynamically stable, and his physical examination is unremarkable except for what is seen in the photo.
How would you manage his condition?
Diagnosis: Penetrating Neck Injury
Nowhere else in the body are so many vital structures bundled together in such a compact space as in the neck. The sternocleidomastoid muscle separates the anterior and posterior “triangles” of the neck, with most vital structures lying within the anterior region (anterior sternoclei-domastoid belly to midline of neck to lower border of the mandible).
The neck has been separated into three anatomic zones for simplicity. From caudad to cephalad, Zone I is the horizontal area between the suprasternal notch of the clavicle to the cricoid cartilage; it contains the proximal common carotid, vertebral, and subclavian arteries, the trachea, the esophagus, the thoracic duct, the thoracic inlet, the brachial plexus, the lung apex, and the thymus. Zone II is the area from the cricoid cartilage to the angle of the mandible, and contains the common, internal and external carotid arteries, the jugular veins, the pharynx, the larynx, the esophagus, the recurrent laryngeal nerve, the spinal cord, the trachea, the thyroid, submandibular, and parathyroid glands. Zone III is the area from the angle of the mandible to the base of the skull, and it contains the carotid and vertebral arteries, the jugular veins, and the parotid gland.
It is estimated that five percent to 10 percent of all trauma patients evaluated in the ED have penetrating neck injuries (estimated mortality: 3-10%). These can be caused by stabs, punctures, gunshots, and impalements. Zone II injuries are the most common, but Zone I injuries tend to cause the highest mortality because of logistical challenges, the risks of surgical exploration in this area, and the likelihood of pri-mary vascular injury and hemorrhage. Considering the type of penetrating object (projectile vs. blunt) may help to determine the extent of local tissue damage. Obviously, the demarcation of these zones is of limited value when considering the angled track a knife or bullet may make, and a patient may sustain significant internal injuries despite a benign superficial appearance.
Vascular injuries are the most common type of injuries caused by penetrating neck trauma (occurring in 37% of patients in one series, with roughly 10% involving the carotid artery. J Oral Maxillofac Surg 2007;65:691.) Although the tight fascial compartments of the neck make exsanguination less likely, expanding hematomas can compress vital airway structures and quickly cause life-threatening airway compromise.
Rapid resuscitation and stabilization of all injuries should occur following standard trauma evaluation. Patients with penetrating neck wounds require meticulous examination of the airway to determine the extent of injury. Hypotension, active hemorrhage, (expanding) hematoma, focal neurological deficit, stridor, hoarseness, drooling, respiratory distress, subcutaneous emphysema, hemoptysis, hematemesis, bruit, thrill, trismus, focal decreased breath sounds, distorted neck anatomy, and dysphagia are ominous signs of potential or impending airway compromise. Although there is no consensus, early intubation should be considered for any significant penetrating neck injury. A surgical airway may be necessary, and the emergency physician should be prepared to perform this when attempting oral intubation.
If acute hemorrhage is identified, firm direct pressure should be applied to the wound. Wounds generally should not be explored in the ED; this may dislodge a clot and cause uncontrolled hemorrhage. Emergent surgical consultation should be obtained. Empiric antibiotics should be given for all penetrating neck wounds because of the risk of esophageal violation and mediastinitis. It is also important to differentiate self-inflicted versus accidental wounds. All intentional wounds will eventually require psychiatric evaluation.
Management depends on the patient's hemodynamic stability, whether he is symptomatic, the location of the wound, and the index of suspicion for significant injuries. Penetrating injuries to the neck that do not violate the platysma muscle are considered superficial and require only primary closure. Wounds that violate the platysma require more intensive evaluation because of potential aerodigestive and neurovascular injuries.
It is very unlikely for patients who are asymptomatic with a normal physical examination to have a surgical vascular injury (Br J Surg 1993;80: 1534), but pharyngoesophageal injuries are often occult, and can have devastating consequences if undiagnosed and treatment is delayed. (J Trauma 2001;50:289.) Venous injuries also may have devastating outcomes and be more difficult to appreciate on physical examination.
The first recorded successful vascular ligation of a penetrating neck injury was performed by a French surgeon more than 400 years ago, and it resulted in irreversible neurological deficit. (J Vasc Surg 2006;44:86.) Prior to World War II, all penetrating neck injuries were treated with expectant management, which yielded a mortality rate of more than 30 percent by some reports. The pendulum then swung the other direction, and until the 1990s the standard of care for all penetrating neck trauma was surgical exploration. This resulted in an unacceptably high negative exploration rate; some report as high as 35 percent. Currently a more selective surgical approach using diagnostic imaging has been developed. The management for all hemodynamically unstable penetrating neck trauma patients is surgical exploration, but no consensus exists about the ideal diagnostic management of hemodynamically stable patients with the same injuries. (Oral Maxillofac Surg Clin North Am 2008;20:393.)
Obviously the potential morbidity of a missed occult injury can have deleterious and life-threatening consequences including fistulas, persistent hemorrhage, infection, thrombosis, emboli (air or vascular), nerve injury, and pseudoaneurysms. Some surgeons argue that all Zone II injuries should be surgically explored because of the relative straightforward access to the area and the need for high diagnostic sensitivity. (Surg Clin North Am 1991;71:267.) Yet others advocate for a less invasive initial approach. Plain radiographs of the neck and chest can show mediastinal or retropharyngeal air, retained foreign bodies, and bony injury. For patients with suspected aerodigestive injuries, computer tomography with angiography, with or without esophageal studies, is typically adequate. (J Trauma 2008;64:1466.) CT evaluation may be limited by scatter from foreign body fragments (a bullet), noncalcified cartilage (in pediatric patients), or patients with a contrast dye allergy. Some institutions, however, use color flow Doppler ultrasound or traditional angiography to identify vascular injury. (Arch Surg 1995; 130:971.) At other centers, trauma surgeons prefer bronchoscopic evaluation to rule out penetrating thoracic injury, and yet others advocate for observation with serial re-examinations in hemodynamically stable patients who do not have immediately obvious significant injuries.
This patient's wound was surgically explored and debrided, and he had an uneventful recovery period.