Arterial Blood Gas Analysis and Hemodynamic Responses Using One Corrugated Tube in Patients with Oral and Maxillofacial Surgery under General Anesthesia

Background : Most of nonrebreathing circuits were used for pediatrics, not for adults and the high flow of fresh gas and specially designed valve or lever should be needed. The current study was designed to compare between one corrugated tube(universal FTMcircuit) and two corrugated tube in patients with oral and maxillofacial surgery under general anesthesia. Methods : Twenty adults undergoing oral and maxillofacial surgery were anesthetized with enflurane- N2O-fentanyl after radial arterial cannulation. Under the condition with stable vital signs, ventilator was setted with tidal volume 10ml/kg, respiratory rate 11 breaths/min using two separate limbs(expiratory and inspiratory limbs) and one corrugated tube of anesthesia machine. Mean arterial pressure, heart rate, saturated pulse oxygen, end tidal carbon dioxide, peak inspiratory oxygen, arterial blood gas analysis were measured at 15, 30min during the use of each circuit. Results; There were no differences of mean arterial pressure, heart rate, end tidal carbon dioxide, saturated pulse oxygen. peak inspiratory presssure and arterial blood gas analysis between 2 circuits during mechanical ventilation. Conclusions: Universal FTMcircuit of single limb could substituted for the two corrugated tube, especially in patients with oral and maxiolofacial surgery. (Korean J Anesthesiol 1997; 32: 366∼369)