[Clinical comparison of the reusable LMA Classic laryngeal mask and the disposable Soft Seal mask in adult patients].

OBJECTIVES: To compare the clinical behavior of the disposable Soft Seal laryngeal mask to the behavior of the reusable LMA Classic mask.

METHODS: Patients were randomly assigned to 2 groups in which either the LMA Classic or the Soft Seal mask would be used. We assessed time required for positioning and number of attempts, seal pressure, fiberoptic bronchoscopic image, and complications. The masks were inserted by 2 anesthesiologists who were inexperienced in the use of laryngeal masks. We also compared compliance of the cuff in the laboratory.

RESULTS: Sixty patients were enrolled. There were no differences in time required for insertion or number of attempts (first-try success, 83%). The mean (SD) seal pressure was greater in the Soft Seal group at 23 (4) cm H2O than in the LMA Classic group at 20 (4) cm H2O. There were no significant differences in the fiberoptic bronchoscopic images, ventilation, incidence of intraoperative complications, presence of blood on the cuff (LMA Classic, 6 out of 30 vs Soft Seal, 11 out of 29), or postoperative sore throat. In 3 patients in the Soft Seal group the laryngeal mask had to be replaced by an orotracheal tube. Cuff compliance in the laboratory was lower for the LMA Classic than for the disposable mask for all sizes assessed.

CONCLUSIONS: Although the results suggest that the clinical behavior of the 2 masks is similar, the LMA Classic allowed for effective airway management in all of the cases assigned to it, whereas management was effective in 90% of the cases in which the Soft Seal mask was used. The inflatable cuff of the Soft Seal is more compliant in vitro and it provides a higher airway seal pressure than does the LMA Classic.