2001 OPEN FORUM Abstracts
Lab Evaluation of Pulmonetic Systems LTV Ventilator with the Datex-Ohmeda INOvent
John Newhart,RCP; Craig Pedersen, RCPT; Timothy Morris, MD, UCD Medical Center, San Diego,CA.
Background: At our institutionwe used inhaled nitric oxide (INO) to treat hypoxia and pulmonary hypertension.Most of these patients are on mechanical ventilation. When mechanically ventilatedpatient requires transportation within the medical center they are frequentlyplaced on the LTV (Pulmonetic Systems, Colton, CA) portable ventilator. Thepurpose of this study is to determine the effects of using the INOvent (Datex-Ohmeda,Madison, WI) in conjunction with the LTV. We tested for differences in set vs.Indicated volumes, and effects on trigger sensitivity.
Methods: Tidal volume accuracywas investigated by placing a pneumotach (Novametrics VenTrack) between thepatient "Y" and a 2 chamber TTL (Michigan Instruments). Inspired andexpired volumes were recorded from the VenTrack as well as displayed exp. volumesfrom the LTV. Volumes from both sources were plotted out on a graph for comparison.Triggering was assessed by attaching the LTV to one side of a double chamberlung with a Puritan Bennett 840 driving the other chamber. Patient effort wassimulated by a lift bar on the drive chamber lifting the driven side. Sensitivitylevels of 2.4 and 6 lpm, at doses of 0, 5 15, 20, 40, 60 and 80 ppm NO and withoutthe INOvent attached were tested. The flow was measured by placing the VenTrackflow sensor in the expiratory limb of the circuit and identified as the maximumnegative deflection immediately before the start of inspiration.
Results: Measured volumeson the VenTrack and LTV correlated well throughout the range of NO doses tested.Volumes increased proportionate to the NO dose. Measured triggering was up to2 lpm above the set point throughout the range of variables tested. This waseasily compensated for by adjustment of the flow trigger.
Conclusions: Our preliminarytesting found the LTV ventilator to be compatible with the INOvent.