Update 1990 pp 440-447 | Cite as

Continuous Assessment of Cardiopulmonary Function

  • J. B. Downs
Conference paper
Part of the Update in Intensive Care and Emergency Medicine book series (UICM, volume 10)


“Assessment” of oxygenation may entail measurement and calculation of a variety of physiologic variables. However, the oxygen tension of arterial blood (PaO2) is by far the most common measurement utilized in determining the “adequacy” of oxygenation. Because of the ease of measurement, PaO2 often is used as a guide to oxygen therapy, ventilator adjustment, and other therapeutic interventions. Some clinicians have suggested a mathematical manipulation of PaO2, alone or in combination with other variables, to improve diagnostic accuracy and assessment of pulmonary function. The perceived advantage of using the alveolar-arterial O2 tension difference (AAD), the arterial/alveolar oxygen tension ratio (AAI), the PaO2/F1O2 ratio (PFI), etc., rather than the PaO2 alone, often is far greater than the actual advantage. It is apparent that the ease and efficiency of measurements and calculations have played a greater role in the determination of monitoring practices than accuracy and efficacy. Because of advances in monitoring technology during the last decade, a reassessment of monitoring techniques is indicated.


Continuous Positive Airway Pressure Oxygen Tension Oxygen Delivery Oxygen Utilization Continuous Assessment 
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Copyright information

© Springer-Verlag Berlin Heidelberg 1990

Authors and Affiliations

  • J. B. Downs

There are no affiliations available

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