2001 OPEN FORUM Abstracts
The Pulmonetics LTV800Ventilator Supports an Open Breathing Circuit for Portable Mouthpiece Ventilationin Neuromuscular Patients
Louie Boitano MS, RRT, YoshihiroOtaki MD, Joshua Benditt MD, Departments of Respiratory Care, and Pulmonaryand Critical Care Medicine, University of Washington Medical Center, Seattle,WA.
Volume driven mouthpiece ventilationhas been shown to provide both adequate ventilatory support and an improvedquality of life when compared to ventilation by tracheostomy in neuromuscularpatients with chronic respiratory failure. To date, mouthpiece ventilation hasbeen supported by piston actuated volume ventilator systems. These ventilatorsare heavy and require significant space, making their instillation on powerwheelchairs for portable ventilatory support both costly and time consuming.Patients using these systems are often limited in their ability to move withintheir home environment because of the increased length of the wheelchair ventilatorsystem. We tested a new model 800 of the LTV series ventilators by PulmoneticsInc., Colton, CA. The compact, portable LTV 800 ventilator was re-engineeredto support assist breath triggering in the assist/control mode by negative pressurewhereas the previous models have been flow triggered. The LTV 800 was testedusing an open breathing circuit system consisting of an Airlife volume ventilatorcircuit, (Allegance Healthcare Corp.), combined with a 15mm angled mouthpiece,(Respironics Inc.). The ventilator was tested in the assist/control mode atvariable tidal volumes, breath rates and inspiratory flow rates. The low pressurealarm was set at 0 centimeters of water pressure. The ventilator produced accuratebreath volumes on a test lung from 500 to 1500 cc?s. Low inspiratory flow ratesdid not trigger the low pressure alarm and the control breath rate could beset as low as one breath per minute without ventilator alarming by adjustingthe apnea duration to 60 seconds. Negative pressure triggering was set as lowas ?1 centimeter of water pressure without causing autocycling machine breaths.The LTV 800 model ventilator supported an open breathing circuit for mouthpieceventilation under a variable range of breath volumes and inspiratory flow rateswithout low pressure alarming. The LTV 800 ventilator can provide a significantgain in the support of portable open circuit mouthpiece ventilation for neuromuscularpatients with respiratory failure. The LTV 800 ventilator is significantly morecompact and lighter weight than currently used portable volume ventilators.It may provide a lower cost and faster instillation for power wheelchairs aswell as the potential for significantly greater chair maneuverability with amore compact wheelchair ventilator system.