Core temperature measurements through a new airway device, perilaryngeal airway (CobraPLA)

Study Objective: The aim of this study was to test the hypothesis that the intraoperative pharyngeal temperatures obtained on the perilaryngeal airway (PLA), a novel airway device with a larger pharyngeal cuff (when inflated) than the laryngeal mask airway, are similar to tympanic membrane core temperatures. Design: This study is a prospective, simultaneous device comparison. Setting: This study was set at a university hospital. Patients: The study patients included 14 adults with American Society of Anesthesiologists physical statuses I and II, scheduled for minor gynecological or orthopedic surgery. Interventions: A PLA was inserted into the pharynx after induction of general anesthesia. Thermocouples were positioned at 3 sites on the PLA: (1) posterior portion of the head of the airway (tip), (2) midposterior portion of the cuff, and (3) left and right lateral-posterior portions of the cuff. Tympanic membrane thermocouples were inserted. Measurements: Temperature readings from the airway and the tympanic membrane thermocouples were recorded every 15 minutes throughout surgery. Main Results: Temperatures recorded from the lateral-posterior cuff were found to be virtually identical to tympanic membrane temperatures, with 97% of the values differing by less than 0.5°C. Readings from the other 2 sites on the cuff differed considerably more from tympanic membrane values. Conclusions: These data suggest that the PLA can be adapted to monitor core temperature reliably.