title: Impact of oxygen sources on performance of the Ventrain(®) ventilation device in an in vitro set-up.
abstract: BACKGROUND
  The Ventrain(®) (Dolphys Medical, Eindhoven, The Netherlands) is a disposable handheld ventilation device allowing active inspiration and expiration through a transtracheal catheter. This study investigated Ventrain(®) 's performance when used with different clinical oxygen sources in an in vitro set-up.
  
  
  METHODS
  Three anesthesia oxygen sources (wall-mounted flowmeter, respirator oxygen outlet port, and anesthesia ventilator circuit) were used at gas flow rates of 6, 9, 12, and 15 l/min. First, the sources' driving pressures (DP), the insufflation pressure (IP), and the flow at the catheter tip were measured using a gas flow analyzer. Tidal volumes (VT) delivered by the Ventrain(®) were assessed by the ASL5000 test lung (respiratory rate: 15 min(-1), I:E = 1:1, compliance: 100 ml/cmH2O, resistance: 3.06 cmH2O/l/s).
  
  
  RESULTS
  VT ranged from 82 to 483 ml for inspiration and 82 to 419 ml for expiration. Measured IP, flow, and VT were less dependent on the set gas flow rate but more on the source's DP. With rising DP the IP, the flow at the catheter tip and consequently VT increased. At an approximate target I:E ratio of 1:1, the ratio of inspiratory to expiratory VT increased with higher DP and gas flow rates.
  
  
  CONCLUSIONS
  The oxygen sources resulted in clinically different IP, flows, and VT delivered by the Ventrain(®) at given gas flow rates. This needs to be considered in a clinical emergency situation. Integrating an adjustable pressure valve into Ventrain(®) to allow regulation of the lowest necessary IP would make its use safer.
authors.affiliation: Department of Anaesthesia, University Children's Hospital, Zurich, Switzerland.
authors.forename: A R
authors.initials: AR
authors.lastname: Schmidt
authors.affiliation: Institute of Anaesthesiology, University Hospital, Zurich, Switzerland.|Departments of General Anesthesiology and Outcomes Research, Cleveland Clinic, Cleveland, Ohio, USA.
authors.forename: K
authors.initials: K
authors.lastname: Ruetzler
authors.affiliation: Department of Anaesthesia, University Children's Hospital, Zurich, Switzerland.
authors.forename: T
authors.initials: T
authors.lastname: Haas
authors.affiliation: Department of Anaesthesia, University Children's Hospital, Zurich, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Schmitz
authors.affiliation: Department of Anaesthesia, University Children's Hospital, Zurich, Switzerland.
authors.forename: M
authors.initials: M
authors.lastname: Weiss
mesh_terms: D004209:Disposable Equipment; D006801:Humans; D010100:Oxygen / Q000008:administration & dosage*; D012122:Ventilators, Mechanical
chemical_list: D010100:Oxygen