Open AccessModification of the Penlon Nuffield 200 series ventilator and IPPV with a laryngeal mask airway
Author(s) -
Miller D. M.
Publication year - 2000
Publication title -
european journal of anaesthesiology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.445
H-Index - 76
eISSN - 1365-2346
pISSN - 0265-0215
DOI - 10.1046/j.1365-2346.2000.00688.x
Subject(s) - medicine , airway , venturi effect , laryngeal mask airway , leak , anesthesia , tidal volume , regurgitation (circulation) , intermittent positive pressure ventilation , positive pressure , mechanical ventilation , cardiology , respiratory system , inlet , mechanical engineering , environmental engineering , engineering
Summary There is a risk of regurgitation if a laryngeal mask airway is used with intermittent positive pressure ventilation. The lower the pressure gradient between airway and stomach, the less will be the likelihood of stomach insufflation with gas and consequent regurgitation. A flow generator ventilator, such as the Penlon Nuffield 200 which achieves a peak pressure at the end of inspiration at any given tidal volume, is likely to produce a higher peak airway pressure than a pressure generator. Replacing the expiratory valve by a venturi gives a preferable flow pattern with an inspiratory pressure plateau. At equal tidal volumes, the venturi modification provided a 10% lower inflation pressure (standard deviation 6%, P < 0.01) and a 1.8% smaller leak ( P < 0.05) past the laryngeal mask airway. The same comparison but using identical inflation pressures, gave 8% larger tidal volumes (standard deviation 5.1%, P < 0.01) and a 2% smaller leak ( P < 0.01) past the laryngeal mask airway.