Reevaluation of a maneuver to visualize the anterior larynx after intubation.

Abstract

Confirmation of translaryngeal placement of the tracheal tube can be unexpectedly difficult. This study examined the usefulness of displacing the larynx posteriorly with the tracheal tube during laryngoscopy with a straight laryngoscope blade to confirm tracheal tube placement. One hundred ASA Classes I, II, or III patients presenting for elective surgery whose normal anesthetic care included placement of an orotracheal tube via direct laryngoscopy were enrolled in this institutionally approved study after giving their written, informed consent. The view of the larynx at laryngoscopy was graded, and the tracheal tube was then inserted. When the larynx was incompletely exposed, the tracheal tube was displaced posteriorly while the laryngoscope was maintained in the intubating position in an attempt to better visualize the larynx. The effect of the maneuver on Mallampati grade for laryngeal exposure was noted. During laryngoscopy with a Miller blade none of the glottis was initially visualized in 17 patients (Mallampati laryngeal Grades 3 and 4). Thus, the tracheal tube actually was not seen to pass between these patients' vocal cords. Use of the maneuver resulted in improved visualization of the intubated larynx in 12 of these patients, and confirmed tracheal intubation. This maneuver is recommended as an aid to the anesthesiologist in the confirmation of tracheal intubation.