title: Performance of infusion pumps during hyperbaric conditions.
abstract: BACKGROUND
  Many hyperbaric facilities use infusion pumps inside the chamber. It is therefore important to ensure that this equipment will perform accurately during hyperbaric conditions. The authors tested the function and accuracy of the Imed 965 and Infutec 520 volumetric infusion pumps, the Easy-pump MZ-257 peristaltic infusion pump, and the Graseby 3100 syringe pump.
  
  
  METHODS
  The authors calculated the deviations of infused volumes at low and high rates (12-18 and 60-100 ml/h) on three different hyperbaric protocols (up to 2.5, 2.8, and 6 atmospheres absolute [ATA]), resembling a standard hyperbaric oxygen treatment and US Navy treatment tables used for decompression illness and for arterial gas embolism. Two examples of each pump model were examined in every experiment.
  
  
  RESULTS
  The Easy-pump MZ-257 failed to function completely beyond a chamber pressure of 1.4 ATA, making it unsuitable for use inside the hyperbaric chamber. The Graseby 3100 failed to respond to all keyboard functions at 2.5-2.8 ATA, making it unsuitable for use in most hyperbaric treatments. The Imed 965 performed within an acceptable volume deviation (< or =10%) during most hyperbaric conditions. During the compression phase of the profiles used, and for the low infusion rates only, exceptional volume deviations of 20-40% were monitored. The Infutec 520 demonstrated an acceptable deviation (within 10%) throughout all the hyperbaric profiles used, unaffected by changes in ambient pressure or infusion rate.
  
  
  CONCLUSIONS
  Commercially available infusion pumps operating during hyperbaric conditions demonstrate substantial variations in performance and accuracy. It is therefore important that the hyperbaric facility staff make a careful examination of such instruments to anticipate possible deviations in the accuracy of the equipment during use.
authors.affiliation: Israel Naval Medical Institute, Israel Defence Forces Medical Corps, Haifa, Israel. dr_lavon@hotmail.com
authors.forename: Haim
authors.initials: H
authors.lastname: Lavon
authors.forename: Avi
authors.initials: A
authors.lastname: Shupak
authors.forename: Dror
authors.initials: D
authors.lastname: Tal
authors.forename: Avishai
authors.initials: A
authors.lastname: Ziser
authors.forename: Amir
authors.initials: A
authors.lastname: Abramovich
authors.forename: Yoav
authors.initials: Y
authors.lastname: Yanir
authors.forename: Oren
authors.initials: O
authors.lastname: Shoshani
authors.forename: Amnon
authors.initials: A
authors.lastname: Gil
authors.forename: Ronit
authors.initials: R
authors.lastname: Leiba
authors.forename: Zohar
authors.initials: Z
authors.lastname: Nachum
mesh_terms: D006801:Humans; D006931:Hyperbaric Oxygenation; D007260:Infusion Pumps