title: Evaluation of ventilators used during transport of critically ill patients: a bench study.
abstract: OBJECTIVE
  To evaluate the most recent transport ventilators' operational performance regarding volume delivery in controlled mode, trigger function, and the quality of pressurization in pressure support mode.
  
  
  METHODS
  Eight recent transport ventilators were included in a bench study in order to evaluate their accuracy to deliver a set tidal volume under normal resistance and compliance conditions, ARDS conditions, and obstructive conditions. The performance of the triggering system was assessed by the measure of the decrease in pressure and the time delay required to open the inspiratory valve. The quality of pressurization was obtained by computing the integral of the pressure-time curve for the first 300 ms and 500 ms after the onset of inspiration.
  
  
  RESULTS
  For the targeted tidal volumes of 300, 500, and 800 mL the errors ranged from -3% to 48%, -7% to 18%, and -5% to 25% in the normal conditions, -4% to 27%, -2% to 35%, and -3% to 35% in the ARDS conditions, and -4% to 53%, -6% to 30%, and -30% to 28% in the obstructive conditions. In pressure support mode the pressure drop range was 0.4-1.7 cm H2O, the trigger delay range was 68-198 ms, and the pressurization performance (percent of ideal pressurization, as measured by pressure-time product at 300 ms and 500 ms) ranges were -9% to 44% at 300 ms and 6%-66% at 500 ms (P < .01).
  
  
  CONCLUSIONS
  There were important differences in the performance of the tested ventilators. The most recent turbine ventilators outperformed the pneumatic ventilators. The best performers among the turbine ventilators proved comparable to modern ICU ventilators.
authors.affiliation: Réanimation des Urgences et Médicale, Hôpital de la Timone, Marseille, France.
authors.forename: Salah
authors.initials: S
authors.lastname: Boussen
authors.forename: Marc
authors.initials: M
authors.lastname: Gainnier
authors.forename: Pierre
authors.initials: P
authors.lastname: Michelet
mesh_terms: D019985:Benchmarking; D016638:Critical Illness / Q000628:therapy*; D004867:Equipment Design; D006801:Humans; D008954:Models, Biological; D015203:Reproducibility of Results; D012121:Respiration, Artificial / Q000295:instrumentation* / Q000592:standards; D013990:Tidal Volume; D014187:Transportation of Patients / Q000379:methods*; D012122:Ventilators, Mechanical / Q000592:standards*
keywords: ICU patient transport; bench study; inspiratory trigger; mechanical ventilation; pressure support ventilation; transport ventilator; ventilator performances