Evaluation of Head and Neck Position on Oropharyngeal Leak Pressure with Baska Mask and Streamlined Liner of Pharyngeal Airway (SLIPA<sup>TM</sup>): Arandomized Clinical Trial

Abstract

Abstract:The primary objective was to compare oropharyngeal leak pressures of streamlined liner of pharyngeal airway (SLIPA TM ) and Baska mask at different head and neck positions. Assessing the fiberoptic view of glottis and ventilation score of both devices in different positions were the secondary objectives. Sixty patients ASA I-II, 18-60 years of either sex scheduled for short ambulatory surgery were included. Patients were randomly assigned in a 1:1 ratio to either the SLIPA TM or the Baska mask group. The effect of various head and neck positions was evaluated. Neutral position was maintained first then the patient was repositioned in the following positions: maximal extension, maximal flexion, and maximal rotation to the left. In each position, peak airway pressure and oropharyngeal leak pressure were noted. The ventilation score was assessed and fibreoptic views were noted. In both groups, oropharyngeal leak pressures and peak airway pressure were significantly higher with flexion. The fiberoptic score frequently decreased in flexion but with no effect on the ventilation. In comparison between the two devices, there was no significant change in the fibreoptic view of the glottis at different neck positions. So we concluded that, effective ventilation is possible with both Baska mask and SLIPA TM with the head in neutral, flexion, extension, and lateral rotation positions. But care should be taken with extreme flexion and the airway pressures need to be monitored. Baska mask has a better margin of safety than SLIPA TM due to better airway sealing pressures.