Blunt laryngeal trauma presenting as bilateral massive pneumothoraces and subcutaneous emphysema: a multidisciplinary approach to management

Abstract

A 3-year-old boy had an unwitnessed fall from a highchair. The child had no loss of consciousness, vomiting, stridor or respiratory distress but within a few minutes had significant swelling in the neck, scalp and around the eyes. He was brought immediately to the emergency room where he deteriorated rapidly and was intubated with a cuffed oral endotracheal tube. A clinical diagnosis of blunt laryngeal trauma was made. Imaging showed no laryngeal disruption, but did reveal massive bilateral pneumothoraces, that were managed with chest tube. A multidisciplinary meeting with family led to a watchful waiting approach. The patient was successfully extubated at 1 week and healed with a clear voice.

Background

Laryngotracheal trauma is a relatively rare entity accounting for 1 in 30 000 emergency room visits. In spite of its rarity, it remains highly lethal and after intracranial injury is the second most common cause of death following injury to the head and neck.¹ We present a case of blunt paediatric laryngeal trauma, reviewing key anatomic considerations for the paediatric airway and basic airway management principles.

Case presentation

A previously healthy 3-year-old boy presents following an unwitnessed fall from a highchair. At the time, he was agitated and inconsolable. There was no associated change in level of consciousness, vomiting, stridor, voice change or respiratory distress. Over the subsequent 5–10 min, he developed extensive swelling and crepitus along his neck, face and scalp. He was brought to the emergency room immediately.

In the emergency room, the physician noted extensive subcutaneous emphysema along the entire head and neck region. The child became increasingly hypoxic and agitated. It was impossible to assist ventilation using an bag valve bag and because of a falling oxygen saturation and concerns over impending airway obstruction, the decision was made to proceed with intubation. Saturation initially improved following intubation but later dropped. An urgent CT chest demonstrated large bilateral pneumothoraxes (figure 1). Bilateral chest tubes were inserted with improvement in oxygen saturation. The uncuffed oral endotracheal tube was changed to a cuffed one in order to minimise any disruption of the larynx and so that ventilation would bypass the area of the larynx. A CT neck demonstrated extensive surgical emphysema but no evidence of laryngeal disruption or oesophageal injury.

Figure 1.

Child at initial presentation (left), coronal CT demonstrating bilateral pneumothoraxes and extensive subcutaneous emphysema (middle), child at 6-week follow-up (right).

Outcome and follow-up

A presumptive diagnosis of blunt laryngeal trauma was made. Radiology ruled out additional injuries. Following a multidisciplinary meeting with family, a decision was made to proceed with watchful waiting. On anaesthetic lightening there was no evidence of any neurologic sequelae though the patient’s course in hospital was complicated by pneumonia and a femoral line thrombosis. He was successfully extubated at 1 week and healed with normal vocal cord function and a clear voice (figure 1).

Discussion

Blunt trauma is the most common laryngotracheal injury with the basic mechanism consisting of compression of the laryngotracheal cartilages on the cervical spine. Relative to the adult larynx, the paediatric larynx is less susceptible to disruption following blunt trauma.^{2 3} Anatomically, its high position offers some protection by the mandible. Enhanced mobility/pliability make the laryngeal cartilages less prone to fracture. That said, the paediatric larynx is at higher risk for severe soft-tissue injury because of loose attachment of the submucosal tissues to the perichondrium.⁴

Symptoms or laryngeal trauma include voice change, dysphagia, anterior neck pain, stridor, dyspnoea or hemoptysis. Physical examination findings include cervical abrasions or ecchymosis, subcutaneous emphysema and hoarseness.^{5 6}

After the airway has been stabilised, a complete trauma assessment must be performed. Neck and chest radiographs are obtained as part of the initial patient assessment to evaluate for cervical spine fractures, subcutaneous emphysema, pneumothorax or pneumomediastinum. Wherever possible, evaluation of the larynx should be done by an otolaryngologist. Contrast-enhanced CT scan of the neck provides the best radiographic evaluation of the injured larynx. Oesophageal injury must also be ruled out. This can be achieved through esophagography with a water-soluble contrast agent, which avoids potential mediastinal irritation from barium.

The American Academy of Otolaryngology-Head and Neck Surgery recommends that laryngeal trauma be classified according to the Schaefer System as it allows the clinician to formulate treatment decisions based on severity of the injury. Laryngeal injury is graded in an ascending order of severity (I–V) (table 1).^{7 8} Grade I and II injuries are recommended for non-operative management and close observation whereas grade III–V injuries necessitate securing the airway.⁷ This can be achieved through either endotracheal intubation or emergency tracheostomy. Divergent opinion exists with respect to which is more appropriate. The Difficult Airway Society recommends one attempt at intubation followed by emergency tracheostomy.⁹ On the other hand, other groups suggest going directly for tracheostomy as intubation may be hazardous, promoting further laryngeal injury, including the possibility of worsening laryngeal tear and false passage.⁸

Table 1.

Schaefer classification

Grade	Description
1	Minor endolaryngeal hematoma or laceration without any detectable fracture
2	Oedema, hematoma, minor mucosal injury without exposed cartilage or a nondisplaced fracture
3	Massive oedema or hematoma, mucosal tears with exposed cartilage, vocal cord immobility or displaced fractures
4	As above but with severe mucosal disruption, multiple fractures or an unstable laryngeal framework
5	Complete laryngotracheal separation

With respect to the paediatric population, intubation is typically regarded as the quickest method of securing the airway. Emergency tracheostomy is exceedingly difficult in the paediatric population owing to the small size of trachea and pliable cartilage. In this case, failing to intubate on the first attempt, the clinician could consider intubating under direct vision using a rigid bronchoscope or over a flexible bronchoscope. If unsuccessful, one should move to an emergency tracheostomy. All cases require careful airway assessment and close monitoring to identify complications.

Learning points.

• It is important to recognise subtle evidence of laryngeal injury secondary to blunt neck trauma to ensure early diagnosis.

• Blunt laryngeal trauma is the most common form of laryngotracheal injury, and in many cases non-operative management and close observation is sufficient.

• While the primary injury was to the neck, multidisciplinary teamwork is required to manage these patients as multisystem involvement is frequent.