A Comparison of the Oropharyngeal Leak Pressure between the Reusable Classic™ Laryngeal Mask Airway and the Single-use Soft Seal™ Laryngeal Mask Airway

Abstract

We tested the oropharyngeal leak pressure with the reusable laryngeal mask airway and the single-use Soft Seal™ laryngeal mask airway. These two types of laryngeal mask airway (LMA) have a similar design but the reusable LMA cuff is made from silicone whereas the Soft Seal LMA cuff is Polyvinylchloride. Thirty-five healthy subjects were anaesthetized and paralyzed and the two types of Soft Seal LMA were compared in a blinded randomized cross-over trial. The oropharyngeal leak pressure was significantly higher with the Soft Seal than the reuable (21±7.6 and 16±6.7 cm H₂O respectively, P=0.002). However, in four subjects the oropharyngeal leak pressure was higher with the reusable by >4 cm H₂O. We concluded that the reusable LMA may provide a better seal in some individuals but that, on average, the Soft Seal provides a higher oropharyngeal leak pressure than the reusable LMA.