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.