An abnormal ventilation-perfusion relationship can be seen where there are alveolar units with ventilation, but no persistent perfusion. In this video, from our Blood Gas Analysis Essentials course, you'll learn about the pathophysiologic consequences of a functional state of regional lung ventilation unaccompanied by blood flow—physiological dead space.
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Another form of abnormal ventilation perfusion relationship can be seen as a result of alveolar units with ventilation, but no persistent perfusion. Conceptually, any alveolar units with v Q greater than one, but not infinity, can be described as if the units were functionally equivalent to areas of Deadspace.
Areas of high v Q or physiologic Deadspace represent regions of wasted ventilation as far as carbon dioxide elimination is concerned. However, in most disorders characterized by an increase in lung areas with high v Q hypercapnia does not occur. These individuals can compensate for the increase in Dead Space by increasing the overall level of ventilation to keep pa co2 constant.
So, an elevation in arterial carbon dioxide tension would only be seen when the patient can't sustain the overall level of ventilation necessary to compensate. So, I hope you liked this video. Absolutely, make sure to check out the course this video was taken from and to register for a free trial account which will give you access to select the chapters of the course. If you want to learn how Medmastery can help you become a great clinician, make sure to watch the about mastery video. So thanks for watching and I hope to see you again soon.