Background : The laryngeal tube airway (LT) is an extraglottic airway device with a proximal and distal conical cuff designed to secure a patient's airway during either spontaneous breathing or controlled ventilation. Application of this device with the use of N2O may be related to the ischemic change of the oropharyngeal mucosa. The objective of this study was to investigate the time-related intracuff pressure and volume change (which reflects the pharyngeal pressure) of the LT during anesthesia with N2O.