Usefulness of Continuous Trachea for-Management Oxygen I n s u m t i o n into of Upper Airway Obstruction during Anesthesia

Background: Severe complications associated with upper airway obstruction often occur during the perioperative period. Development of a simple and reliable technique for reversing the impaired airway patency may improve airway management. The purpose of the current study is to evaluate the usefulness of transtracheal oxygen insufflation (TTI) for management of upper airway obstruction during anesthesia and to explore the mechanisms of "I in detail. Methods: During propofol anesthesia in eight spontaneously breathing patients, the upper airway cross-sectional area and pressure-flow measurements during neck flexion with TTI were compared with those during triple airway maneuvers (TAM) without lTI. Blood gas analyses assessed efficacy of CO, elimination during lTI in an additional nine patients. ResuZts: 'IT1 achieved adequate Pa,-o2 and P+2 levels equivalent to those during TAM. In addition to a significantly smaller cross-sectional area during TIT, the location and slope of the pressure-flow relation during TTL completely differed from those during TAM, indicating that upper airway resistance was much higher during TII. Notably, minute ventilation during 'IT1 was significantly smaller than that during TAM, suggesting reduced dead space or other mechanisms for CO, elimination. Conclusions: 1TI is capable of maintaining adequate blood gases through mechanisms different from those of conven-