A 40-year-old female presented at 8:00 A.M. with a swollen lip but no rash, speaking full sentences. She was immediately given intravenous diphenhydramine, methylprednisolone, and famotidine. At 10:30 A.M., she developed neck swelling, difficulty swallowing, and dyspnea and was given subcutaneous epinephrine and nebulized albuterol while an anesthesiologist was called for possible difficult airway intubation and an otolaryngologist was called for possible emergent tracheostomy. The patient decompensated and the anesthesiologist was unable to intubate the patient. The otolaryngologist took 45 minutes to place the tracheostomy due to soft-tissue swelling obscuring the trachea, during which time the patient became apneic, went into PEA cardiac arrest, and developed anoxic brain injury. Two months later, the patient died and the patient's family filed suit against the emergency physician, anesthesiologist, and otolaryngologist.
According to the most recent National Emergency Airway Registry (NEAR) data, intubation success rates by emergency physicians are over 99%.1 Thus, the truly difficult intubations are infrequently faced, and the failed airway even more rare. The difficult airway exists in a patient when conventional face mask ventilation is problematic or tracheal intubation is difficult, requiring an expert with technical skill for success. Factors such as micrognathia, a short neck, a large tongue, craniofacial abnormalities, and obesity are chronic conditions associated with a difficult airway but do not inherently necessitate emergent airway management. However, conditions such as angioedema, epiglottitis, Ludwig angina, a retropharyngeal abscess, tracheal trauma, a traumatic/expanding neck hematoma, and cervical trauma are examples of an acutely difficult airway requiring emergent management. When these patients present with dyspnea or respiratory distress, precise, immediate action is required to avert life-threatening decompensation or permanent morbid debility. Unlike other specialties, when these patients present to the emergency department (ED), we cannot postpone or cancel the case. Thus, emergency physicians must be especially astute and prepared for a rapid escalation of care and invasive management.
While difficult bag-mask ventilation and difficult intubations each occur separately in approximately 5% of patients,1,2,3,4 difficult bag-mask ventilation and difficult intubations occur concomitantly in much fewer patients.5 In fact, less than 1% of patients require a surgical airway for emergent management,6 likely due to the development of multiple tools for managing the difficult airway.
ANTICIPATING THE DIFFICULT AIRWAY
When patients present in extremis, a detailed history is precluded. However, several historical factors portend a difficult airway and should be rapidly determined:
History of oral, neck, or cervical spine surgery or irradiation.
History of oral or neck tumor, cellulitis, or abscess.
History of neck or mandibular arthritis or other joint immobility.
Presentation as a result of oral, facial, neck, or cervical spine trauma.
Use of anticoagulants or presence of a coagulopathy.
Likewise, a focused physical exam of the head and neck should be performed. The LEMON Law mnemonic has ...