A comparison of the laryngeal mask airway ProSeal and the laryngeal tube airway in paralyzed anesthetized adult patients undergoing pressure-controlled ventilation.
We compared the laryngeal mask airway ProSeal (PLMA) and the laryngeal tube airway (LTA), two new extraglottic airway devices, with respect to: 1) insertion success rates and times, 2) efficacy of seal, 3) ventilatory variables during pressure-controlled ventilation, 4) tidal volume in different head/neck positions, and 5) airway interventional requirements. One-hundred-twenty paralyzed anesthetized ASA physical status I and II adult patients were randomly allocated to the PLMA or LTA for airway management. A standardized anesthesia protocol was followed by two anesthesiologists experienced with both devices. The criteria for an effective airway included a minimal expired tidal volume of 6 mL/kg during pressure-controlled ventilation at 17 cm H(2)O with no oropharyngeal leak or gastric insufflation. First attempt success rates at achieving an effective airway were similar (PLMA: 85%; LTA: 87%), but after 3 attempts, success was more frequent for the PLMA (100% versus 92%, P = 0.02). Effective airway time was similar. Oropharyngeal leak pressure was larger for PLMA at 50% maximal recommended cuff volume (29 +/- 7 versus 21 +/- 6 cm H(2)O, P < 0.0001), but was similar at the maximal recommended cuff volume (33 +/- 7 versus 31 +/- 8 cm H(2)O). Tidal volumes (614 +/- 173 versus 456 +/- 207 mL, P < 0.0001) were larger and ETCO(2) (33 +/- 9 versus 40 +/- 11 mm Hg, P = 0.0001) lower for the PLMA. The number of airway interventions was significantly less frequent for the PLMA. Airway obstruction was more common with the LTA. When comparing mean tidal volumes in different head/neck positions, the quality of airway was unchanged in 56 of 60 patients (93%) with the PLMA and 42 of 55 (76%) with the LTA (P = 0.01). The PLMA offers advantages over the LTA in most technical aspects of airway management in paralyzed patients undergoing pressure-controlled ventilation.


CONCLUSIONS
The laryngeal mask airway ProSeal offers advantages over the laryngeal tube airway in most technical aspects of airway management in paralyzed patients undergoing pressure-controlled ventilation.
Department of Anaesthesia and Intensive Care, Cairns Base Hospital, The Esplanade, Cairns 4870, Australia. jbrimacombe@austarnet.com.au
Joseph
J
Brimacombe
Christian
C
Keller
Lawrence
L
Brimacombe
D000328:Adult; D000768:Anesthesia, General; D004311:Double-Blind Method; D006801:Humans; D007442:Intubation, Intratracheal / Q000295:instrumentation*; D017214:Laryngeal Masks; D019148:Neuromuscular Blockade; D010243:Paralysis / Q000139:chemically induced; D011175:Positive-Pressure Respiration / Q000379:methods*; D011187:Posture / Q000502:physiology; D011446:Prospective Studies; D015656:Respiratory Mechanics; D013990:Tidal Volume / Q000502:physiology