A Multicenter Study Comparing the ProSeal and Classic Laryngeal Mask Airway in Anesthetized, Nonparalyzed Patients

Background: The laryngeal mask airway ProSeal (PLMA), a new laryngeal mask device, was compared with the laryngeal mask airway Classic (LMA) with respect to: (1) insertion success rates and times; (2) efficacy of seal; (3) fiberoptically determined anatomic position; (4) orogastric tube insertion success rates and times; (5) total intraoperative complications; and (6) postoperative sore throat in nonparalyzed adult patients undergoing general anesthesia, hypothesizing that these would be different.

Methods: Three hundred eighty-four nonparalyzed anesthetized adult patients (American Society of Anesthesiologists physical status I-II) were randomly allocated to the PLMA or LMA for airway management. In addition, 50% of patients were randomized for orogastric tube placement. Unblinded observers collected intraoperative data, and blinded observers collected postoperative data.

Results: First-attempt insertion success rates (91 vs. 82%, P = 0.015) were higher for the LMA, but after three attempts success rates were similar (LMA, 100%; PLMA, 98%). Less time was required to achieve an effective airway with the LMA (31 +/- 30 vs. 41 +/- 49 s; P = 0.02). The PLMA formed a more effective seal (27 +/- 7 vs. 22 +/- 6 cm H2O; P < 0.0001). Fiberoptically determined anatomic position was better with the LMA (P < 0.0001). Orogastric tube insertion was more successful after two attempts (88 vs. 55%; P < 0.0001) and quicker (22 +/- 18 vs. 38 +/- 56 s) with the PLMA. During maintenance, the PLMA failed twice (leak, stridor) and the LMA failed once (laryngospasm). Total intraoperative complications were similar for both groups. The incidence of postoperative sore throat was similar.

Conclusion: In anesthetized, nonparalyzed patients, the LMA is easier and quicker to insert, but the PLMA forms a better seal and facilitates easier and quicker orogastric tube placement. The incidence of total intraoperative complications and postoperative sore throat are similar.