The Neck

Abstract

Major vascular and aerodigestive structures pass through the neck with little or no protection from overlying bone, muscle, or soft tissue. This means an injury to the neck can result in loss of the airway from a tracheal injury, exsanguination from injury to a major blood vessel, or sepsis from a major pharyngeal or esophageal injury. It is also an area that most general surgeons infrequently operate on, so thorough preparation is the only way to make up for the lack of familiarity in an emergent case.

Civilian Translation of Military Experience and Lessons Learned

• Demetrios Demetriades 

Civilian Versus Battlefield Injuries

Neck injuries pose major diagnostic and therapeutic challenges because of the dense concentration of many important organs in a small anatomical area and the difficult surgical exposure of many of these structures. However, only about 20% of civilian gunshot injuries and 10% of stab wounds require operative intervention. The remaining patients can safely be managed nonoperatively. Routine surgical exploration of civilian-penetrating neck injuries is not an acceptable practice because of the unacceptable rate of nontherapeutic operations.

Civilian injuries may differ from battlefield injuries, which are often the result of high-velocity missiles or explosions, diagnostic resources may not be available, and the continuity of care may be problematic. However, if the appropriate resources are available, the principles of evaluation and management used in civilian injuries are applicable to war injuries.

Clinical Evaluation

A careful clinical examination according to a written protocol almost always diagnoses or highly suspects all significant injuries requiring operative intervention. In order to avoid missing significant signs or symptoms, it is strongly recommended to perform the examination according to a written protocol. Appropriate investigations such as CT angiogram, color flow Doppler (CFD) , and endoscopy confirm with certainty the presence or not of any injuries to vital structures.

The clinical examination should be systematic, and evaluate for injuries to the vessels, the aerodigestive tract, the spinal cord, the nerves, and the lungs. The presence of hard signs is highly diagnostic of significant injuries requiring operation. Patients with “soft signs” require further evaluation by means of vascular or endoscopic studies.

Vascular Injuries

“Hard” signs and symptoms highly diagnostic of vascular trauma include active bleeding, unexplained shock, expanding or pulsatile hematoma, absent or significantly diminished peripheral pulses, and a bruit on auscultation.

“Soft” signs and symptoms suggestive but not diagnostic of vascular trauma include mild shock, stable hematoma, slow bleeding, abnormal brachial–brachial index (BBI), and proximity missile tract. Unexplained neurological findings (coma, hemiplegia) may be due to a carotid injury. Only about 22% of patients with soft signs have any type of vascular injuries, and fewer than 5% need an operation.

Aerodigestive Injuries

“Hard” signs or symptoms highly diagnostic of significant laryngotracheal trauma include respiratory distress, air bubbling through a neck wound, and massive hemoptysis. There are no hard signs diagnostic of pharyngoesophageal trauma.

“Soft” signs and symptoms suspicious of aerodigestive trauma include subcutaneous emphysema, hoarseness, painful swallowing, and minor hemoptysis. These patients need evaluation by esophagogram or endoscopy. Only about 15% of patients with soft signs have a significant aerodigestive injury.

Neurological Injuries

The examination of the nervous system should include the Glasgow Coma Score, localizing signs, pupils, cranial nerves, spinal cord, brachial plexus (median, ulnar, radial, axillary, musculocutaneous nerves), the phrenic nerve, and the sympathetic chain (Horner’s syndrome).

Operation or Observation

Patients with hard signs of vascular injury (pulsatile bleeding, large or expanding hematoma, shock) or aerodigestive tract (major hemoptysis, hematemesis, air bubbling through the wound) should be taken directly to the OR. The absence of any clinical signs or symptoms suggestive of vascular or aerodigestive injury reliably excludes significant injuries to these structures that require therapeutic intervention. All patients with soft signs of vascular or aerodigestive tract injury should undergo CT angiography. Selective use of catheter-based angiography, endoscopy, and contrast swallow for equivocal CT results should be considered in the appropriate cases.

General Management

Any external bleeding should be controlled by direct digital pressure. Protective C-spine collars should be avoided or applied loosely in the presence of large neck hematomas because of the risk of airway obstruction. C-collars are not necessary in knife injuries. In order to reduce the risk of air embolism, all patients with suspected venous injuries should be placed in the Trendelenburg position, and the neck wound should be occluded with gauze. In zone 1 injuries, intravenous lines should be avoided on the same side as the injury because of the possibility of a proximal venous injury.

Airway Establishment

Some patients with penetrating neck trauma present with airway compromise due to direct laryngotracheal trauma or due to external compression by a large hematoma. Securing the airway in these patients is a top priority, but it can be a difficult and potentially dangerous procedure. Pharmacological paralysis for endotracheal intubation should always be performed in the presence of a surgeon ready to perform a cricothyroidotomy, if the intubator cannot visualize the cords or there is concern about a false extratracheal passage of the endotracheal tube. On the other hand, endotracheal intubation without pharmacological paralysis can cause patient straining and coughing and may precipitate massive hemorrhage from a previously contained vascular injury. If the patient is stable, fiber-optic nasotracheal intubation under light sedation is the safest option. The optimal method of airway establishment should be individualized.

Temporary Bleeding Control

In most cases, any neck bleeding can be controlled by direct digital pressure in the wound. If digital pressure is not effective because of difficult anatomical location, such as in zone 1 or 3, insertion of the tip of a Foley catheter into the wound and inflation of the balloon with sterile water may control the bleeding.

Patients arriving in the emergency department with imminent or established cardiac arrest should undergo an emergency resuscitative thoracotomy, cardiac massage, thoracic aorta cross clamping, and aspiration of the right ventricle of the heart for air embolism in suspected venous injuries. Any injuries to the left subclavian vessels can be accessed and controlled at the apex of the pleural cavity through the thoracotomy.

Tips and Pitfalls

• Cervical collars in the presence of a neck hematoma can cause airway obstruction.

• Never place an intravenous line in the arm on the same side as a supraclavicular injury, because of the possibility of the presence of a subclavian venous injury.

• In zone I injuries, the presence of a peripheral pulse does not exclude a significant subclavian or axillary arterial injury.

• Reduce the risk of air embolism in venous injuries by placing the patient in the Trendelenburg position and occluding the wound with gauze.

• Always prepare the chest in case an extension sternotomy is needed.

  • In esophageal or tracheal injuries, do not miss a second back wall injury.

  • Delayed revascularization (>4–6 h after the injury) of carotid injuries in patients with neurologic deficits can convert an ischemic brain infarct into a hemorrhagic infarct.

  • Anterior subluxation of the mandible may improve the exposure of the distal internal carotid artery by an additional 2–3 cm.

  • Distal control of internal carotid injuries at the level of the base of the skull may be achieved with intravascular balloon catheter tamponade.