Monitoring Cardiopulmonary Function with Dual Oximetry

  • J. B. Downs
Part of the Developments in Critical Care Medicine and Anesthesiology book series (DCCA, volume 25)


“Assessment” of oxygenation may entail measurement and calculation of a variety of physiologic variables. However, the oxygen tension of arterial blood (P a02) is by far the most common measurement utilized in determining the of “adequacy” of oxygenation. Because of the case 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 Pa02, alone or in combination with other variables, to improve diagnostic accuracy and assessment of pulmonary function. The pereeived advantage of using the alveolararterial O2 tension difference (AAD), the arterial/alveolar oxygen tension ratio (AAI), the PaO2/FIO2 ratio (PFI), etc., rather than the PaO2 alone, often is far greater than the aetual advantage. It is apparent that the ease and effideney 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 Mixed Venous Oxygen Saturation Oxyhemoglobin Saturation Oxyhemoglobin Dissociation Curve 
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General References

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Copyright information

© Springer Science+Business Media Dordrecht 1992

Authors and Affiliations

  • J. B. Downs

There are no affiliations available

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