The Science Journal of the American Association for Respiratory Care

2010 OPEN FORUM Abstracts

TRANSPORT VENTILATOR PERFORMANCE DURING PRESSURE SUPPORT VENTILATION.

Andrew D. Marchese1, Demet Sulemanji1, Joseph Krathovil1, Jesús Villar2, Robert M. Kacmarek1; 1Respiratory Care, Massachusetts General Hospital, Boston, MA; 2Multidisciplinary Organ Dysfunction Evaluation Research Network, Research Unit, Hospital Universitario Dr. Negrin, Las Palmas de Gran Canaria, Spain

Background: A number of new transport ventilators have recently entered the market none of which have been evaluated. Patients are increasingly being ventilated with spontaneous breathing modes. The ability of the Uni-Vent 731 (Impact), PB540 (Covidien), HT70 (Newport), Oxylog 3000 (Drager) and Trilogy O2 (Philips) to provide pressure support (PS) was evaluated using the IngMar ASL 5000 lung simulator. Methods: Simulator settings: respiratory rate 20 breaths/min, inspiration time 0.8 seconds, active inspiration 3.5% of breath cycle time (BCT), a hold at maximum muscle effort of 0.5% BCT, and return of pressure to baseline 22.7% BCT, maximum muscle effort (Pmus) 5 and 10 cmH2O. Three combinations of compliance (C) and resistance (R): C 60 mL/H2O/R10 cmH2O/L/sec (C60/R10); C60/R5; and C30/R10 were evaluated. PS was set 15cm H2O above PEEP levels of 5 and 15 cmH2O. Manufacturers default settings and optimal setting of trigger sensitivity, rise time and termination criteria were compared. The following variables are reported: Time to Trigger (TT): The time, in milliseconds, from start of the breath to ventilator triggering. Pressure to Trigger (PT): The magnitude of pressure difference, measured in cmH2O, between initial airway pressure at start of breath and the negative deflection in airway pressure needed to trigger. Time to Baseline (TB): The time, in milliseconds, from ventilator triggering to the point when airway pressure reestablishes and maintains baseline pressure (PEEP), Inspiratory T90 (T90). Results: Optimal setting outperformed default setting. Optimal setting results are listed in table below. Conclusion: Considerable performance variability exists across these ventilators and is affected by Pmus and optimal settings. Some perform equivalent to ICU ventilators. Sponsored Research - None Indicates difference between low and high Pmus setting. * Indicates difference among ventilators.