Teaching Case

A 48-year-old female patient was admitted following a fall in the bathroom sustaining direct trauma to her anterior neck on the sink. On admission she complained of pain, a hoarse voice and neck swelling. Flexible nasendoscopy showed a left vocal cord palsy with mild oedema around the arytenoids.

A CT scan of the neck and thorax was organised. A fracture of the left lateral wall of the trachea immediately inferior to the vocal cords is seen resulting in a defect measuring 16mm by 10mm (Figures 1, 2).
Significant surgical emphysema extends from the base of skull into temporalis, the orbits and infra-temporal fossae. There is emphysema throughout the soft tissues of the neck, chest wall and mediastinum.

Laryngotracheal injuries are uncommon, but pain, subcutaneous emphysema, haemoptysis, dysphagia, change in voice and dyspnoea should alert the clinician to potential tracheal trauma even in the absence of visible external signs [1, 2]. External signs may include bruising, haematoma, visible wound or pain on palpation of the trachea and larynx [2]. Symptoms may not necessarily correlate with the degree of internal injury and in a stable patient the larynx should be assessed through flexible nasolaryngoscopy [1]. Lacerations, swelling, cord immobility and even exposed cartilage in severe trauma can be potentially seen on direct examination. Blunt injury to the airway can have subtle signs and symptoms in addition to normal laryngoscopy findings, therefore if there is strong or persistent clinical suspicion that such injury exists, high resolution CT scanning can provide valuable diagnostic information [1].
Schaefer et al divided laryngeal injuries into 5 groups depending on severity [2, 3]. In Group 1 there is no laryngeal fracture but minor lacerations or haematomas are present. Group 2 demonstrates haematoma, oedema and mucosal disruption without exposed cartilage. Group 3 and 4 injuries are similar and can result in vocal cord immobility, laryngeal fracture or dislocation, massive haematoma, and large mucosal lacerations. Group 4 injuries tend to result in multiple or unstable fractures. In group 5 there is complete laryngotracheal separation. Some injuries are more easily visible on nasoendoscopy whereas fractures are best demonstrated on imaging, therefore to classify injuries a combined approach is required [2].
Soft tissue injuries such as haematoma, oedema and lacerations can be observed on CT. Lesions of high attenuation are suggestive of a haematoma, laryngeal oedema causing asymmetric soft tissue thickening or airway narrowing [2]. Mucosal lacerations can be difficult to see but disruption of the mucosa with air in the paraglottic space is suggestive [2].
Severe trauma can involve fractures of one or more laryngeal cartilages. The thyroid cartilage is most commonly affected with the arytenoids the least [2]. Cricoid cartilage fractures can cause sudden airway obstruction [2].
Airway assessment and stabilisation are the main focus of initial management. If a decision to intubate via the endotracheal route is made, care must be taken to avoid further damaging the larynx. Alternatively a tracheostomy or surgical airway can be considered. It is also important to exclude injuries elsewhere as around 50% of patients with laryngeal trauma have in addition cranial, thorax or abdominal injuries [2].