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.