You have been called to the Emergency Room to review a previously well adult male who has sustained a penetrating injury to the root of the neck.

a)    Describe the anatomy of the root of the neck on the left side describing the clinically important
structures that may be injured.    (50% marks)


b)    Outline the issues specific to management of a penetrating neck injury.    (50% marks)

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College Answer

a)

The root of the neck is the junction between the thorax and the neck. It opens into, and is the cervical side of, the superior thoracic aperture, through which pass all structures going from the head to the thorax and vice versa. The root of the neck is bound laterally by the first rib, anteriorly by the manubrium, and posteriorly by the T1 vertebrae.

From anterior to posterior, the major contents are:

Subclavian artery and branches

  • vertebral artery
  • internal thoracic artery
  • thyrocervical trunk
  • costocervical trunk

Subclavian vein and tributaries (EJV)

Trachea

Oesopahagus

Vagus nerve

Recurrent Laryngeal nerve

Dome of pleura

Brachial plexus

Lymphatics and thoracic duct

Phrenic nerve

Sympathetic chain, stellate ganglion

Scalene muscle.

Clavicle

b)

Requires management at a trauma centre with appropriate expertise. May require multiple speciality input - interventional radiology, ENT, vascular, cardiothoracic.

Airway issues:

  • The possibility of laryngeal/ tracheal injury and the risk of intubating the “false airway passage”. Consider tracheostomy under local anaesthesia.

Urgent surgical exploration required for haemodynamic compromise, expanding or pulsatile haematoma, extensive subcutaneous emphysema, stridor, or neurological deficit with intra op bronchoscopy/ endoscopy/ angiography if available.

If    no    indication  for    urgent    surgical    exploration    requires    CT    angiography    (or    equivalent)    with    close
observation  in    ICU  +/-  flexible  laryngoscopy  +/-  endoscopy  +/-  oral  contrast  swallow  study.

Additional Examiners’ Comments:

Most candidates were not aware of the issues and management priorities associated with this type of trauma.

Discussion

Anatomy is not our strong suite. This question describes injury to Zone 1 of the neck, where all the important stuff seems to be. For an excellent revision of the important issues, the interested trainees are directed to Karim Brohi's 2002 write-up of neck wounds on trauma.org.

Generic approach to management:

  1. Assess for airway compromise (eg. by expanding haematoma)
    Assess for airway injury (eg. subcutaneous emphysema)
    Organise expert help.
    Awake fiberoptic intubation by an experienced operator would be ideal, with an ENT surgeon on standby. Risks include intubating a false passage, or causing complete tracheal disruption.
  2. Assess for respiratory compromise.
    Ausculation and percussion may reveal pneumothorax due to injury of the dome of pleura, or the raised hemidiaphragm of a phrenic nerve injury
  3. Assess the circulation in the arm on the affected side. There may be vascular compromise.
    Angiography is very important; occlusion balloons may be very useful in controlling haemorrhage from deep vessels.
  4. Assess the neurology of the patient, starting with GCS.
    Verterbral artery damage may present with spinal syndromes (eg. Brown-Sequard) or brainstem stroke signs
    Carotid artery damage may present with hemispheric stroke signs

Specific concerns in a Zone 1 injury:

  • massive haemothorax
  • arteriovenous fistula (subclavian vessels)
  • Thoracic duct damage (if it was the left side of the neck, as it tends to be with a right-handed attacker coming from the front)
  • brachial plexus damage
  • Horner's syndrome

Reasons for urgent surgical exploration:

  • airway compromise (stridor, etc)
  • haemorrhgic shock
  • expanding haematoma (or, especially if it is pulsatile)
  • stroke-like symptoms