To investigate the efficacy and safety of supraglottic jet ventilation for laser surgery on the larynx, ten studies were performed in seven children scheduled for laser excision of juvenile laryngeal papillomata. The children were anesthetized using halothane, nitrous oxide, fentanyl 3 .mu.g/kg, and a succinylcholine infusion. After the Leonard-Jako laryngoscope was in place, jet ventilation with 70% nitrous oxide in oxygen was begun through a 12-gauge Medicut intravenous cannula inserted in the right-hand light channel of the laryngoscope. Tracheal, inspired, and end-tidal oxygen, nitrous oxide, nitrogen, and carbon dioxide were determined by mass spectrometry simultaneously with arterial blood gases. Oxygen and carbon dioxide levels were always within normal limits, the end-tidal to arterial differences averaging 50 .+-. 9 and -2 .+-. 1 (SEM) mm Hg, respectively. Room air entrainment averaged 32 .+-. 2%. The end-tidal nitrous oxide average 39 .+-. 2%. The advantages of this technique are that it leaves the larynx completely free for the surgeon and it eliminates the possibility of endotracheal tube ignition. Supraglottic jet ventilation for this surgical procedure was determined to be effective and relatively safe.
