Objective: To compare the ProSeal laryngeal mask airway (PLMA) and the standard laryngeal mask airway (SLMA) for intermittent positive pressure ventilation (IPPV) in a randomized auto control design.
Methods: Fifty adult patients with American Society of Anesthesiologists (ASA) physical status 1-2, scheduled for elective plastic surgery under general anesthesia were recruited. After the routine intravenous anesthesia induction, the PLMA and the SLMA were inserted randomly in sequence into each patient and inflated to an intracuff pressure of 60 cm H(2)O (1 cm H(2)O=0.098 kPa), airway seal pressure and lung ventilation satisfaction were evaluated, and fiberoptic (FOB) scores of the cuff anatomic position were measured. The mean expired volume and the mean peak inspiratory pressure of five continuous breaths were calculated after IPPV with 10 ml/kg tidal volume was performed.
Results: Without cuff inflation, airway seal pressure was higher with the PLMA than with the SLMA (P<0.05), and adequate or acceptable lung ventilation was obtained in 46 (92%) patients with the PLMA, but only 22 (44%) patients with the SLMA. When the air volume required to obtain an intracuff pressure of 60 cm H(2)O, adequate lung ventilation was obtained in 50 patients with the PLMA, but only 28 patients with the SLMA, and the inflation volume and sequential airway seal pressure were higher with the PLMA than with the SLMA (both P<0.05), and the airway seal pressure with the PLMA was not less than with the SLMA in each patient. The ventilation volume was higher with the PLMA than with the SLMA, except in 2 patients. The FOB score of the cuff position was lower with the PLMA than with the SLMA (P<0.05). The mean expired tidal volume and the mean peak inspiratory pressure were not significantly different between 29 patients with the PLMA and 21 patients with the SLMA for airway maintenance during operation (both P>0.05).
Conclusion: Compared with SLMA, PLMA can achieve a higher airway seal pressure and potentially isolate the glottis and the upper esophagus, and is safer and more effective for positive pressure ventilation.