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    Hi , can someone please explain to me why in hypoventilation the CO2 levels will rise less than the O2 levels, imp quite confused. The O2 levels went from 95% to 60% and the C02 levels from 40 to 45 mmHg.
    thanks , help much appreciated
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    (Original post by emmalav)
    Hi , can someone please explain to me why in hypoventilation the CO2 levels will rise less than the O2 levels, imp quite confused. The O2 levels went from 95% to 60% and the C02 levels from 40 to 45 mmHg.
    thanks , help much appreciated
    If you're hypoventilating your respiratory rate will be reduced so you won't be inspiring "fresh" oxygen, so you will become hypoxic. Similarly, when your respiratory rate is reduced you won't be blowing off as much CO2, so your PaCO2 will rise i.e. respiratory acidosis.
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    The whole point of breathing is to take in oxygen and get rid of carbon dioxide. If you aren't breathing enough, the values start shifting the other way

    Oxygen levels always fall before CO2 levels start to rise. This is because the body has a much tighter homeostatic control over pCO2 than pO2. Hypoxia = type 1 respiratory failure. Hypoxia + hypercapnia = type 2 respiratory failure
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    (Original post by emmalav)
    Hi , can someone please explain to me why in hypoventilation the CO2 levels will rise less than the O2 levels, imp quite confused. The O2 levels went from 95% to 60% and the C02 levels from 40 to 45 mmHg.
    thanks , help much appreciated
    You are not using equivalent units here. You can have sats of 95 with a pO2 of 8.0 or sats of 60 with a pO2 of 7.0, which would make your example (wherever those numbers were plucked from) not illustrate your question at all. You need to use partial pressures for both for a fair comparison.
 
 
 
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