Reliable detection of inspiration and expiration by computer

  • J. Brunner
  • G. Wolff
  • H. Langenstein
  • G. Cumming
Article

Abstract

A new computer assisted method is proposed to distinguish between the inspiratory and expiratory phases of breathing. The method is based on the analysis of both gas flow and CO2-concentration. The algorithm is effective and reliable and is most suitable in critical care patients when an uninterrupted sequence of breaths is to be analysed immediately at the bedside.

Marked variations in tidal volume such as are seen in intermittent mandatory ventilation or spontaneous breathing during the phase of weaning from the ventilator, artefacts such as mechanical vibrations of the flow transducer or its connecting tubes do not disturb the analysis.

Keyword

Pulmonary function variables gas exchange single breath analysis 
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Copyright information

© Martinus Nijhoff Publishers 1985

Authors and Affiliations

  • J. Brunner
    • 1
  • G. Wolff
    • 1
  • H. Langenstein
    • 1
  • G. Cumming
    • 1
  1. 1.Division of Cardiothoracic Surgery, Clinical PhysiologyDepartment of Surgery of the University of BaselKantonsspital BaselSwitzerland

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