Effect of Nitrous Oxide Anaesthesia on Endotracheal Cuff Pressure

Abstract

Aim: When N2Ois used for general anaesthesia, it diffuses into the air-filled endotracheal cuff causing the cuff pressure to rise by over inflating the cuff, which results in tracheal damage. This study aimed to estimate changes in the endotracheal-cuff pressure with time during oxygen-air- and oxygen-N2O -induced anaesthesia and to determine its sore throat and hoarseness incidence. Methods: Fifty patients with American Society of Anesthesiologists physical status 1-2, aged 18-60 years were icluded to our study. Orotracheal intubation was performed using polyvinyl chloride high volume-low pressure endotracheal tubes. The AIR group 40% O2/60% air and N2O group 40% O2/60% N2O was used. The endotracheal cuff pressure at 5, 10, 15, 20 minutes immediately after intubation and at 10-minute intervals were recorded. When the cuff pressure reached 45 cm H2O, was attenuated to 25-30-cm H2O. At the post operative first and the 24th hour, the patients were queried for sore throat and hoarseness. Results: The N2O -group cuff pressure rose from the fifth minute onwards. Also, the N2O group had a higher incidence of sore throat and hoarseness. Conclusion: N2O results in elevated cuff pressure and tracheal morbidities. Cuff-pressure should be routinely monitored during anaesthesia using N2O.

Keywords

• General anaesthesia
• nitrous oxide
• tracheal intubation
• cuff pressure
• tracheal morbidities