What every surgeon should know about the traumatic airway

Initial assessment

The initial moments after a trauma patient arrives to the emergency department or resuscitation bay are crucial for obtaining basic information from ambulatory emergency medical teams. Essential information includes the mechanism of injury, interventions provided en route, and the overall condition as stable, unstable, moribund, or deceased. The primary survey of any trauma patient is systematic and standardized, as per the Advanced Trauma Life Support Protocols, to ensure that all findings are disclosed. This initial assessment is comprised of a rapid evaluation that prioritizes the stabilization of crucial physiologic functions, in accordance with the acronym ABCDE, accordingly: (1) airway patency, (2) breathing, (3) circulation with hemorrhage control, (4) disability evaluation with brief neurologic examination, and (5) exposure of the entire patient via removal of all articles of clothing.

The most critical step in the primary management of an acute airway trauma is recognition of the injury. Therefore, clinicians must be particularly vigilant in discerning signs of airway trauma during the initial moments of the encounter; a high index of suspicion is especially warranted in patients with anterior cervical trauma. Laryngeal trauma is frequently associated with symptoms of hoarseness, dyspnea, dysphagia, dysphonia, and pain with phonation. Conversely, laryngeal-tracheal injury (which mandates immediate airway control) often presents with crepitus, stridor, hemoptysis, anterior cervical edema, ecchymoses, and cervical lacerations.

Signs indicative of an accompanying vascular injury include shock, persistent bleeding, and a hematoma that may be limited without jeopardizing the airway. Patients on anticoagulant therapy are more prone to bleeding and the formation of edema. Should the aforementioned arise, impending airway obstruction should be anticipated to prevent the ensuant abrupt deterioration of the patient. Because of the inability to predict the clinical course, postponing tracheal intubation until the hospital is preferred. Nevertheless, comprehensive monitoring of the patient along with continuous recording of the hematoma’s size is crucial. Should the hematoma enlarge or the patient show progressive signs of airway compromise, prophylactic intubation should be performed immediately. Regardless of the environmental setting, a difficult intubation should be anticipated and planned for accordingly. If the transport time is anticipated to be too long, a lower threshold for initiating intubation should be considered. Once the airway is secured, a meticulous diagnostic workup should be immediately initiated to confirm the exact location of the injury and guide appropriate management decisions, including preparation for a potential surgical intervention. In particular, the workup should include fiberoptic examination of the pharynx, larynx, trachea, and esophagus.

Airway control methods

Control of a traumatized airway can be achieved via routine intubation or cricothyroidotomy. While most anesthesiologists are skilled in intubation via direct or fiberoptic laryngoscopy, most surgeons are skilled in establishing a surgical airway.

Upon initial assessment of a traumatized airway, endotracheal intubation may appear the most beneficial and efficient method for gaining airway control. However, in certain situations, care should be taken to consider scenarios where a cricothyroidotomy would be more advantageous. For example, in patients presenting with injuries at or directly below the level of the larynx, proceeding with an endotracheal intubation would impede further examination of the injury and potentially aggravate an existing laryngeal injury. In comparison, a tracheostomy would allow for joint examination of both the site of the injury and the site above the injury via direct laryngoscopy. There are certainly benefits of a cricothyroidotomy, though they must be weighed against the increased risk of laryngeal-tracheal separation in pursuing a surgical approach in patients with significant neck injuries.

Interventional support

The Manual In-Line Immobilization (MILI) technique, commonly referred to as Manual In-Line Stabilization, serves to stabilize the cervical spine during medical interventions, such as airway management. With this technique, the objective is to apply a sufficient amount of contradicting force to the head and neck and create an equal but opposite motion to neutralize potential movement of the cervical spine during an intervention such as laryngoscopy. To perform MILI, the patient is generally placed in the supine position with the head and neck in a neutral position. The assistant, or second provider, performing the technique is positioned at either the head of the bed or the bedside and is physically rotated to face the head of the bed. The assistant then proceeds to bilaterally grasp the patient’s mastoid processes with his or her fingertips while cradling the occiput in the palms of the hands. Once MILI is in place, the anterior portion of the cervical collar is removed to facilitate airway interventions by enabling greater mouth opening.

Although MILI is overall effective in reducing spinal movements during airway maneuvers and interventions, the procedure is less efficacious at the substantive site of injury. During a MILI-dependent intervention, spinal movement is caudally restricted by the weight of the torso and cephalically restricted by the applied immobilization forces. However, the cervical midpoint remains unrestricted by any force. In theory, the application of traction forces during MILI serves to reduce midcervical movement, though the use of these forces during in-line immobilization remains discouraged because traction forces may disrupt the site of the injury. Avoiding traction forces is especially paramount during the application of MILI, when severe ligamentous injuries result in gross spinal instability. Lennarson discussed how spinal stabilization via tractional forces during direct laryngoscopy in a patient with a complete ligamentous injury resulted in excess distraction. Similarly, Kaufmann demonstrated that the application of in-line traction in four patients with ligamentous disruptions resulted in spinal column lengthening and distraction at the site of injury. Overall, the use of MILI is certainly effective, but must be used with cognizance of any potential ligamentous injuries.