Local Anesthesia of the Airway

Procedures on the upper airway in an awake patient are challenging because of local factors such as excessive salivation, presence of gag reflex, and activation of cough reflex, as well as because of the systemic hemodynamic response caused by the stimulation of autonomic nervous system.

Anesthesia of the airway is needed for attempts to access a difficult airway or for procedures performed through the airway in awake patients. In patients with recognized difficult airway, intubation under general anesthesia might lead to the risk of loss of control on the airway. Elective awake intubation is a safer option in these patients and is facilitated by abolishing airway reflexes by local anesthetic techniques. Local anesthesia of the airway is complicated due to the multiple nerves that are to be blocked. A thorough knowledge of the anatomy is essential for a successful procedure.

These blocks are mainly performed to abolish reflexes and provide patient comfort during manipulation and instrumentation of the airways in an awake patient during the following:

• Direct laryngoscopy

• Bronchoscopy

• Nasal intubation

• Fiber optic intubation ^{[1, 2]}

• Some procedures on the head and neck

Most of these procedures are frequently done in patients with compromised airway before establishing endotracheal intubation for the induction and maintenance of anesthesia.

Absolute contraindications

Patient refusal is an absolute contraindication.

Relative contraindications

A patient on anticoagulation is a relative contraindication, as is distorted anatomy that interferes with the proper identification of structures to perform the block due to the following:

• Tumors

• Surgical deformities or reconstruction

• Arteriovenous malformations

If the structures are identified properly and knowledge of the anatomy is good, these blocks can be performed easily and with a high rate of success with the least amount of complications.