You are preparing to provide an awake intubation and general anesthesia to a 64-year-old smoker with a history of extremely difficult tracheal intubation. Shortly after achieving topicalization of the airway with 20% benzocaine spray, the patient starts complaining of dyspnea and lightheadedness. His oxygen saturation measured by pulse oximetry declines to 84 percent and remains at that level despite the administration of 100 percent oxygen by facemask. Administration of which of the following would be the MOST appropriate therapy?
Benzocaine, available in 10 percent, 15 percent, and 20 percent solutions, is an ethyl ester of para-aminobenzoic acid; it is water soluble and widely used for topicalization of the airway during awake intubation. The 20 percent benzocaine solution contains 200 mg/mL, which can deliver between 60 mg (0.3 mL) to more than 200 mg (>1 mL) with every 1 second spray. Benzocaine is a component in Cetacaine, which contains 14 percent...