You are the emergency physician on duty for aeromedical transport calls. You are called to the scene of a motor vehicle collision in a remote area. Seventeen minutes into the flight, you hear from the on-scene paramedics that a young man hit a tree and flipped his car. He is the only occupant and is still trapped in the car. The rescuers have difficulty in extricating him from the vehicle. On landing, you see firefighters preparing to use a heavy-extrication tool (“Jaws of Life”). As you exit the helicopter, the ground paramedic informs you that the accident scene is secure and that the patient is a 25-year-old obese man, unconscious, with stable vital signs. As you approach the vehicle, you note major front-end damage to the car, encroaching on the vehicle’s interior, the airbag deployed, and the patient apparently unresponsive behind the steering column. The A- and B-column on the driver’s side of the car appeared to have struck the left side of the patient’s head, and both lower extremities are trapped under the dashboard. Vital signs are stable and he is unresponsive to pain. He is breathing spontaneously with high-flow oxygen delivered via a non-rebreather face mask with a cervical spine collar applied and two large bore intra-venous cannulas placed in the antecubital fossae.

What Are the Considerations Extricating the Patient from the Vehicle?

With organized traffic control and firefighters ensuring scene safety, a decision must be made about the urgency of extrication. A rapid extrication may be necessary in cases of impending arrest or uncontrollable bleeding. This strategy follows the rule “life before limb” and accepts the risk of further injuries to extremities and spine. A planned and deliberate rescue approach can be considered if there are no immediate life-threatening situations exist, such as a burning vehicle or markedly unstable vital signs. In the case of this patient, access to the patient had already been provided by the rescuers, permitting assessment of the patient by the emergency medical services (EMS) personnel and application of basic airway maneuvers and insertion of intravenous lines. Following the initial medical interventions, the rescuers would use a heavy-extrication tool to remove the roof of the vehicle and a hydraulic spreader to create space under the dashboard. The patient can then be extricated with full spine precautions.

What Are the Major Considerations According to the Advanced Trauma Life Support (ATLS) Guidelines?

According to the ATLS guidelines, the primary assessment of the patient addresses the airway, breathing of the patient, circulation, and disability (ABCD).¹ After rescuer and patient safety, airway management has the highest priority. In this unconscious patient, the airway is in jeopardy and needs to be secured early. It must be assumed that the patient has suffered a severe traumatic brain injury. Oxygenation and ventilation are crucial steps in the initial management of the patient to avoid hypoxemia and hypercarbia, both of which worsen any brain injury. With such extensive vehicle damage, injuries other than to the brain, are very likely: cervical spine injury, pneumothorax or flail chest, intra-abdominal injuries—all must be considered once the airway is assured.

Due to the impacted legs under the dashboard, early extrication is unlikely. Since the patient’s vital signs are stable and a rapid extrication may put a cervical spine injury at risk, a planned and careful extrication is preferable. Airway management must be performed while the patient is still inside the vehicle.

Are There Any Special Considerations in This Case?

Special considerations in this case include urgent airway management in a difficult environment with limited patient access and resources. Access to a patient is usually gained by cutting the A- and B-column of the vehicle using the heavy-extrication tool and flipping the roof backwards, a procedure which may be time-consuming. In this case urgent airway management is necessary due to the traumatic brain injury with a resultant loss of airway reflexes. Tracheal intubation is still the gold standard in securing a patient’s airway. However, a possible cervical spine injury as well as limited neck movement, and combined with limited access to the patient’s head will certainly make airway management using direct laryngoscopy (DL) extremely difficult if not impossible.

There is growing evidence to suggest that tracheal intubation under field conditions may be associated with no patient benefit and may increase risk of adverse patient outcome.^2–4 Mort⁵ found a positive correlation between complications and number of DL intubation attempts in the pre-hospital setting. Data from these studies suggest that there should be a limit to the number of intubation attempts or that DL be avoided in favor of alternative methods to secure the patient’s airway.

How Would You Assess the Patient’s Airway?

Signs of an airway at risk and inadequate breathing, such as sound of obstruction, gasping, indrawing, use of accessory muscles, and cyanosis can be evaluated within seconds at the scene and must not be missed. Airway evaluation should include signs of airway trauma, neck trauma, and tracheal deviation. Several assessment tools can be used to assess a patient’s airway and to predict difficulties (see Chapter 1). However, these tools are of limited use in this pre-hospital setting of a trapped motor vehicle collision victim due to limited patient access, unfavorable patient positioning, and poor patient cooperation. Given the patient’s unconscious state, position, and the difficulty of access, it must be assumed airway management will be challenging.

How Is the Airway Usually Managed in Trauma?

Beyond clinical signs of airway patency and adequacy of breathing, effective oxygenation and ventilation should be determined as quickly as practicable via pulse oximetry and end-tidal CO₂ measurement.¹ Oxygenation should be improved by high-flow oxygen via a non-rebreather face mask. All patients who are in acute respiratory distress or who are not breathing are in need of an immediate airway intervention. A rapid assessment of airway anatomy, appropriate to field conditions, must be done in case ventilatory assistance is required. While the mnemonic MOANS (see section “Difficult BMV: MOANS” in Chapter 1) may predict a difficult bag-mask-ventilation (BMV), this assessment tool is not useful for an unresponsive patient. If BMV is difficult in this unresponsive patient due to airway obstruction (e.g., a large tongue), the obstruction can simply be relieved by lifting the chin or by the jaw-thrust maneuver, even though there may be a chance of aggravating C-spine injury. Similarly, the use of an oropharyngeal airway in the unconscious patient with no gag reflex or a nasopharyngeal airway in a patient with no facial or head trauma can be helpful in accomplishing a patent airway to facilitate BMV.

Patients with a Glasgow Coma Scale score of 8 or less require prompt tracheal intubation. Factors which may predict difficulties with advanced airway maneuvers have to be identified. The mnemonic LEMON (see section “Difficult DL Intubation: LEMON” in Chapter 1) is helpful in predicting a difficult DL. However, its use in an unresponsive patient is limited. If no difficulties are anticipated, tracheal intubation with or without drug assistance should follow. If unsuccessful, adjuncts such as the Eschmann Tracheal Introducer (ETI, commonly known as “gum-elastic bougie”), extraglottic devices (EGDs) should be considered. In the case of inability to intubate the trachea and to ventilate the patient, a surgical airway should be established.¹

What Are Your Airway Options in This Patient?

Due to the critical condition of the patient with suspected cervical spine injury and the difficult working environment, airway management will be challenging. The options will depend on skills and level of training of the EMS practitioner. To avoid significant complications, advanced airway techniques should be attempted only by experienced EMS practitioners skilled in alternative methods of airway management. Practitioners with basic skills should rely on chin lift, jaw thrust, and tongue pull as basic airway maneuvers. However the risk of hypoxemia and hypercarbia has to be balanced against the risk of further aggravating a spinal cord injury with jaw thrust maneuvers, should a simple chin lift is not sufficient to clear the obstructed airway. Basic airway maneuvers have to be performed with caution. In addition to the above-mentioned basic maneuvers, practitioners with advanced airway training should consider the placement of an EGD, such as a Laryngeal Mask Airway or Laryngeal Tube. The type of EGD used will be determined by the protocols of the EMS system. Experienced practitioners should at this point consider establishing a definitive airway using tracheal intubation. DL, video-laryngoscopy (VL), intubating LMA, lightwand, or even cricothyrotomy may be used to provide oxygenation and ventilation. Each technique of airway management carries with it the risk of complications. These must be weighed against the risk of lethal hypoxemia coupled with the skills of the practitioner in the adverse environment of the field. Complications of placement of a definitive airway are esophageal intubation, aspiration, and hypoxemia as a result of prolonged intubation attempts. Regardless of the practitioner’s experience and level of training, the number of intubation attempts should be limited, as repeated attempts increase the risk of morbidity and mortality.⁵

What Is the Role of the EGD in the Trauma Patient?

EGDs are the first alternative in the cannot intubate, cannot oxygenate situation. They have gained popularity as the primary pre-hospital airway management of the trauma patient.^6–9 Martin et al.⁸ reported a success rate of 94% in pre-hospital use of LMA in trauma patients with all insertions performed in 10 seconds or less. Adequate oxygenation and ventilation was provided with patient saturations ranging between 97% and 100% and end-tidal CO₂ between 24 and 35 mm Hg.⁸ Multiple second-generation laryngeal masks have been introduced which incorporate an alternate channel for drainage of gastric contents and placement of a gastric tube. Second-generation laryngeal masks (see Chapter 13), for example, the LMA-Supreme, have even higher success rates in placement. Bosch et al.¹⁰ and Länkimäki et al.¹¹ reported a successful placement in 100% by ground paramedics in pre-hospital airway management. Laryngeal Tubes (see Chapter 13) have gained some popularity in pre-hospital airway management. However there are complications associated with the pre-hospital use of Laryngeal Tubes, such as significant tongue swelling, distention of the stomach, and significant bleeding due to malpositioning in the piriform sinus.¹²