Use of a closed-airway suctioning system during anesthesia

We evaluated the efficacy of a closed airway suctioning (CAS) system in sixteen ASA Class I-II patients undergoing surgery of the extremities. All patients were anesthetized with 50% N2O and oxygen with adequate halogenated anesthesia. Full muscle relaxation was provided and all patients were ventilated with an anesthesia volume controlled ventilator. Endotracheal suctioning without preoxygenation was performed during anesthesia in randomly selected patients by either the CAS or the standard suctioning (SS) technique with a 30 minute rest period between suctioning. Both CAS and SS, used 14Fr catheters, were applied intermittently for 15 seconds at (-)150 mmHg suctioning pressure. SaO2 was continuously monitored throughout the suction period by a pulse oximeter. Arterial blood gas sample was drawn before each suction and 30 sec., 1 min, 3 min, 5 min, 10 min, 15 min, 30 min afterwards. No alteration of SaO2 or PaO2 was noted during CAS but significant lowering of PaO2 was noted for SS at the 30 seconds and 1 minutes post-suctional points. Potential advantages of CAS include: 1) PEEP can be maintained during suctioning. 2) Operating room pollution is minimized. 3) Accidental contamination of both the patient and the anesthesiologist can be prevented. 4) Time is saved during frequent intraoperative suctioning as no preoxygenation is required. 5) There is no need to turn off the anesthetic gases. We conclude that as CAS can maintain steady PaO2 during airway suctioning, it may be a better alternative for repeated intraoperative suctioning.