IT IS well recognized that the perfect anesthesia for bronchoscopy has yet to be found.1 Recently general anesthesia has gained popularity for endoscopic procedures. A number of techniques to overcome the hypoventilation associated with the administration of a general anesthetic have been reported.2-5 Normal arterial oxygen saturation and adequate carbon dioxide removal during bronchoscopy have been considered by some to be one of the advantages of general anesthesia with assisted ventilation.
It is our impression that topical anesthesia has several advantages, not the least of which is the ability to perform the examination without depending on assisted ventilation. Failure to provide adequate ventilation and prevent respiratory acidosis may predispose the patient to cardiac arrest, especially since many of the patients who require bronchoscopic examination have pulmonary insufficiency and chronic respiratory acidosis.
In order to investigate the effect of topical anesthesia and bronchoscopy on the arterial oxygen pressure (P