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Journal of Clinical Monitoring

, Volume 3, Issue 3, pp 194–200 | Cite as

Computer-assisted capnogram analysis

  • Huib R. van Genderingen
  • Nikolaus Gravenstein
  • Jan J. van der Aa
  • Joachim S. Gravenstein
Algorithm

Abstract

Characteristic abnormal carbon dioxide waveforms from patients with mechanically ventilated lungs are observed when, for example, valves are incompetent, the airway is obstructed, the breathing circuit becomes disconnected, or a patient overrides mechanical ventilation with spontaneous breaths. Automated observation of the carbon dioxide waveform provides a uniform, concise, and consistent interpretation of the capnogram. This article describes a computer algorithm for analyzing and classifying capnograms as normal or as belonging to one of the categories above. The algorithm also generates a diagnostic message when the capnogram deviates from a learned norm for at least three consecutive waveforms (and thus reduces the influence of artifacts). Clinical experience shows reliable waveform recognition by the algorithm.

Key words

Algorithm Carbon dioxide: measurement Complications: accidents Equipment: circuits computers ventilators Measurement techniques: computer algorithms infrared capnography waveform analysis Monitoring: ventilation 

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Copyright information

© The BOC Group Inc 1987

Authors and Affiliations

  • Huib R. van Genderingen
    • 1
  • Nikolaus Gravenstein
    • 1
  • Jan J. van der Aa
    • 1
  • Joachim S. Gravenstein
    • 1
  1. 1.Department of AnesthesiologyUniversity of Florida College of MedicineGainesville

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