title: Performance characteristics of five new anesthesia ventilators and four intensive care ventilators in pressure-support mode: a comparative bench study.
abstract: BACKGROUND
  During the past few years, many manufacturers have introduced new modes of ventilation in anesthesia ventilators, especially partial-pressure modalities. The current bench test study was designed to compare triggering and pressurization of five new anesthesia ventilators with four intensive care unit ventilators.
  
  
  METHODS
  Ventilators were connected to a two-compartment lung model. One compartment was driven by an intensive care unit ventilator to mimic "patient" inspiratory effort, whereas the other was connected to the tested ventilator. The settings of ventilators were positive end-expiratory pressures of 0 and 5 cm H2O, and pressure-support ventilation levels of 10, 15, and 20 cm H2O with normal and high "patient" inspiratory effort. For the anesthesia ventilators, all the measurements were obtained for a low (1 l/min) and a high (10 l/min) fresh gas flow. Triggering delay, triggering workload, and pressurization at 300 and 500 ms were analyzed.
  
  
  RESULTS
  For the five tested anesthesia ventilators, the pressure-support ventilation modality functioned correctly. For inspiratory triggering, the three most recent anesthesia machines (Fabius, Drägerwerk AG, Lübeck, Germany; Primus, Drägerwerk AG; and Avance, GE-Datex-Ohemda, Munchen, Germany) had a triggering delay of less than 100 ms, which is considered clinically satisfactory and is comparable to intensive care unit machines. The use of positive end-expiratory pressure modified the quality of delivered pressure support for two anesthesia ventilators (Kion, Siemens AG, Munich, Germany; and Felix, Taema, Antony, France). Three of the five anesthesia ventilators exhibited pressure-support ventilation performance characteristics comparable to those of the intensive care unit machines. Increasing fresh gas flow (1 to 10 l/min) in the internal circuit did not influence the pressure-support ventilation performance of the anesthesia ventilators.
  
  
  CONCLUSIONS
  Regarding trigger sensitivity and the system's ability to meet inspiratory flow during pressure-supported breaths, the most recent anesthesia ventilators have comparable performances of recent-generation intensive care unit ventilators.
authors.affiliation: Department of Anesthesia and Critical Care B (DAR B), Hôpital Saint-Eloi, Centre Hospitalier Universitaire Montpellier, Université Montpellier 1, Montpellier, France. s-jaber@chu-montpellier.fr
authors.forename: Samir
authors.initials: S
authors.lastname: Jaber
authors.forename: Didier
authors.initials: D
authors.lastname: Tassaux
authors.forename: Mustapha
authors.initials: M
authors.lastname: Sebbane
authors.forename: Yvan
authors.initials: Y
authors.lastname: Pouzeratte
authors.forename: Anne
authors.initials: A
authors.lastname: Battisti
authors.forename: Xavier
authors.initials: X
authors.lastname: Capdevila
authors.forename: Jean-Jacques
authors.initials: JJ
authors.lastname: Eledjam
authors.forename: Philippe
authors.initials: P
authors.lastname: Jolliet
mesh_terms: D000769:Anesthesia, Inhalation / Q000295:instrumentation*; D003422:Critical Care; D006801:Humans; D066298:In Vitro Techniques; D008954:Models, Biological; D011312:Pressure; D012122:Ventilators, Mechanical; D015919:Ventilators, Negative-Pressure