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Old 06-18-2013
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Lungs Why Respiratory Alkalosis in Emphysema!

Why there's normal or decrease pco2 and respiratory alkalosis in emphysma??

I mean since it's an OBSTRUCTIVE disease i thought there should be CO2 retention and thus respiratory acidosis, not alkalosis.

Please help!
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I think emphysema is a mixture of obstructive and restrictive pattern.
Alveoli get destroyed and merge. As a result there is a significant decrease in oxygenation surface. Pao2 decreases, metabolic acidosis emerges, and with tachypnea the body tries to get rid of acid (co2). Therefore you get a decreased co2. And as for obstructive pattern, the merged alveoli is like a balloon, pressing the airways, interfering with expiration(mainly) and apparently an increase in co2! But this increase can be downed to normal by tachypnea. So normal or decreased co2.
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Old 06-18-2013
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Originally Posted by Mhd. View Post
Why there's normal or decrease pco2 and respiratory alkalosis in emphysma??

I mean since it's an OBSTRUCTIVE disease i thought there should be CO2 retention and thus respiratory acidosis, not alkalosis.

Please help!
emphysema is pink puffer disease, there is loss of both alveoli and blood vasculature, so there is no CO2 retention. in real world, patients have combination of emphysema and chronic bronchitis.
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Originally Posted by Mhd. View Post
Why there's normal or decrease pco2 and respiratory alkalosis in emphysma??

I mean since it's an OBSTRUCTIVE disease i thought there should be CO2 retention and thus respiratory acidosis, not alkalosis.

Please help!
Emphysema affects more perfusion and chronic bronchitis affects more ventilation. The pink puffers, emphysema patients use accessory muscles to hyperventilate and reduce pco2 and blue bloaters, chronic bronchitis , try to hyperventilate but with plugs of mucus it is ineffective so they have high pco2
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Old 06-18-2013
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Originally Posted by shoty View Post
emphysema is pink puffer disease, there is loss of both alveoli and blood vasculature, so there is no CO2 retention. in real world, patients have combination of emphysema and chronic bronchitis.
What about blue bloaters?

Edit: already explained above...........I should refresh the page before asking questions.
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Thanks guys, that helped alot
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