Canadian Anaesthetists’ Society Journal

, Volume 14, Issue 3, pp 220–231 | Cite as

Evaluation of a pneumotachograph for controlled ventilation in childhood

  • J. B. Owen-Thomas


A T-piece pneumotachograph has been evaluated experimentally to determine its suitability for use during controlled pulmonary hyperventilation. The pressure drop across the instrument is sufficiently linear per unit of flow to allow minute volumes of up to 8 L. to be recorded. During intermittent flow there is an error of measurement ranging from —2.8 per cent for rates of breathing up to 100 per minute, to +5 per cent for rates between 100 and 200 per minute. Calibration of the pneumotachograph and integrator can be carried out using a syringe. When compared with room air, 50 per cent nitrous-oxide-oxygen gives a similar integrator deflection, enabling this gas mixture to be used during the period of study without the need to apply a gas viscosity correction factor to the integrator deflection obtained. ab ]Fr|RéSUMé

On a étudié un pneumotachographe pour déterminer s’il convient de l’utiliser pour l’hyperventilation pulmonaire contrôlée. La baisse de pression à travers l’instrument est assez stable par unité de débit pour permettre d’enregistrer des volumes minute jusqu’à huit litres. Durant un débit intermittent, il y a une erreur de calcul qui va de -2.8 pour cent lorsque la respiration est de 100 ou moins par minute, jusqu’à + 5 pour cent lorsque la respiration est de 100 à 200 par minute.


Control Ventilation Intermittent Flow Syringe Plunger Integrator Channel Spirometer Volume 
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Copyright information

© Canadian Anesthesiologists 1967

Authors and Affiliations

  • J. B. Owen-Thomas
    • 1
    • 2
  1. 1.Registrar to the Intensive Therapy UnitAlder Hey Children’s HospitalLiverpoolEngland
  2. 2.Department of AnaestheticsHospital for Sick ChildrenToronto

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