Intensive Care Medicine

, Volume 35, Issue 8, pp 1368–1376

A bench study of intensive-care-unit ventilators: new versus old and turbine-based versus compressed gas-based ventilators

  • Arnaud W. Thille
  • Aissam Lyazidi
  • Jean-Christophe M. Richard
  • Fabrice Galia
  • Laurent Brochard
Original

DOI: 10.1007/s00134-009-1467-7

Cite this article as:
Thille, A.W., Lyazidi, A., Richard, JC.M. et al. Intensive Care Med (2009) 35: 1368. doi:10.1007/s00134-009-1467-7

Abstract

Objective

To compare 13 commercially available, new-generation, intensive-care-unit (ICU) ventilators in terms of trigger function, pressurization capacity during pressure-support ventilation (PSV), accuracy of pressure measurements, and expiratory resistance.

Design and setting

Bench study at a research laboratory in a university hospital.

Methods

Four turbine-based ventilators and nine conventional servo-valve compressed-gas ventilators were tested using a two-compartment lung model. Three levels of effort were simulated. Each ventilator was evaluated at four PSV levels (5, 10, 15, and 20 cm H2O), with and without positive end-expiratory pressure (5 cm H2O). Trigger function was assessed as the time from effort onset to detectable pressurization. Pressurization capacity was evaluated using the airway pressure–time product computed as the net area under the pressure–time curve over the first 0.3 s after inspiratory effort onset. Expiratory resistance was evaluated by measuring trapped volume in controlled ventilation.

Results

Significant differences were found across the ventilators, with a range of triggering delays from 42 to 88 ms for all conditions averaged (P < 0.001). Under difficult conditions, the triggering delay was longer than 100 ms and the pressurization was poor for five ventilators at PSV5 and three at PSV10, suggesting an inability to unload patient’s effort. On average, turbine-based ventilators performed better than conventional ventilators, which showed no improvement compared to a bench comparison in 2000.

Conclusion

Technical performance of trigger function, pressurization capacity, and expiratory resistance differs considerably across new-generation ICU ventilators. ICU ventilators seem to have reached a technical ceiling in recent years, and some ventilators still perform inadequately.

Keywords

Mechanical ventilation Pressure-support ventilation Work of breathing Inspiratory trigger Bench study 

Supplementary material

134_2009_1467_MOESM1_ESM.doc (491 kb)
Supplementary material 1 (DOC 490 kb)

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Arnaud W. Thille
    • 1
    • 2
    • 3
  • Aissam Lyazidi
    • 1
    • 2
    • 3
  • Jean-Christophe M. Richard
    • 4
    • 5
  • Fabrice Galia
    • 1
    • 2
    • 3
  • Laurent Brochard
    • 1
    • 2
    • 3
  1. 1.Medical Intensive Care Unit, AP-HPCentre Hospitalier Albert Chenevier-Henri Mondor HospitalCreteilFrance
  2. 2.INSERM U955 (team 13)CreteilFrance
  3. 3.University of Paris 12CreteilFrance
  4. 4.Medical Intensive Care UnitHôpital Universitaire Charles NicolleRouenFrance
  5. 5.UPRES EA3830RouenFrance