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-   -   How does asthma lead to cyanosis? (http://www.physicsforums.com/showthread.php?t=472491)

sameeralord Feb13-11 03:12 PM

How does asthma lead to cyanosis?
 
As title suggest. Thanks :smile:

Ozicell Feb14-11 12:46 AM

Re: How does asthma lead to cyanosis?
 
Quote:

Quote by sameeralord (Post 3135936)
As title suggest. Thanks :smile:

Through lack of oxygen in the blood I believe! Skin and mucous membranes begin to look bluish!

sameeralord Feb14-11 03:35 AM

Re: How does asthma lead to cyanosis?
 
Thanks for the reply but I think people with ashtma have less problem in inhaltion, but more problem in exhalation. So it is the resultant increase in carbon dioxide shifting the hameoglobin dissociation curve to the right that causes this. I posted this topic to clarify?

thorium1010 Feb14-11 04:13 AM

Re: How does asthma lead to cyanosis?
 
Quote:

Quote by sameeralord (Post 3136891)
Thanks for the reply but I think people with ashtma have less problem in inhaltion, but more problem in exhalation. So it is the resultant increase in carbon dioxide shifting the hameoglobin dissociation curve to the right that causes this. I posted this topic to clarify?

No asthma has problem with inhalation also (due to narrowing of bronchi). So there is hypoxia which is why there is cyanosis.

sameeralord Feb14-11 05:58 AM

Re: How does asthma lead to cyanosis?
 
Quote:

Quote by thorium1010 (Post 3136910)
No asthma has problem with inhalation also (due to narrowing of bronchi). So there is hypoxia which is why there is cyanosis.

But when you breathe in don't bronchi dilate, but practically I can see what you are saying is right.

mtc1973 Feb14-11 02:37 PM

Re: How does asthma lead to cyanosis?
 
There are more problems associated with exhalation but of course if bronchial muscle tone is high then inhalation rates will also be slowed. But the additional exhalational effects come from the relationship between lung volume and airway diamater.
Incidentally asthmatics are generally not oxygen limited - it is a sign of severe ER requiring asthma if you see a change in blood PO2.
Again - most asthmatics are not hypoxic. This is a severe life threatening situation when an astrhmatic does develop low PO2.

nismaratwork Feb14-11 03:38 PM

Re: How does asthma lead to cyanosis?
 
The bottom line here is very simple: hypoxic leukocytes = cynanosis. It doesn't really matter if it's from the binding of cyanide, someone holding a bag over your head, or some fashion in which your breathing is restricted. Unless it's peripheral vasoconstriction... see what mtc1973 said. Oxygenated air being displaced by panic-gasps and poor exhalation can lead to a rapid crisis, but it's uncommon. More often you pass out, and your breathing is still labored, but not smothering.

thorium1010 Feb15-11 01:27 AM

Re: How does asthma lead to cyanosis?
 
Quote:

Quote by mtc1973 (Post 3137672)
Incidentally asthmatics are generally not oxygen limited - it is a sign of severe ER requiring asthma if you see a change in blood PO2.
Again - most asthmatics are not hypoxic. This is a severe life threatening situation when an astrhmatic does develop low PO2.



This is not correct . Asthmatics , during an attack of asthma are hypoxic (depending on severity).

most of the cases are mild to moderate form and are usually reversible by drugs

sameeralord Feb15-11 06:24 AM

Re: How does asthma lead to cyanosis?
 
Quote:

Quote by mtc1973 (Post 3137672)
There are more problems associated with exhalation but of course if bronchial muscle tone is high then inhalation rates will also be slowed. But the additional exhalational effects come from the relationship between lung volume and airway diamater.
Incidentally asthmatics are generally not oxygen limited - it is a sign of severe ER requiring asthma if you see a change in blood PO2.
Again - most asthmatics are not hypoxic. This is a severe life threatening situation when an astrhmatic does develop low PO2.

This is exactly what our teacher drummed into our heads today. If you were in class teacher would have been very impressed :smile:

PS: Why didn't you tell this yesterday?

nismaratwork Feb15-11 08:41 AM

Re: How does asthma lead to cyanosis?
 
Quote:

Quote by thorium1010 (Post 3138466)
This is not correct . Asthmatics , during an attack of asthma are hypoxic (read oxygen saturation).

I think you need to do 2 things.

1.) Consider what is meant by hypoxia in this thread, given that it's in the context of cyanosis.
2.) Tell me if you understand that "PO2" is "oxygen saturation"... pulse oxygen, "pulse ox", that little cute red light thing they put on your finger? Yeah, the "Pulse Oximeter".

thorium1010 Feb15-11 10:07 AM

Re: How does asthma lead to cyanosis?
 
Quote:

Quote by nismaratwork (Post 3138820)
I think you need to do 2 things.

1.) Consider what is meant by hypoxia in this thread, given that it's in the context of cyanosis.
2.) Tell me if you understand that "PO2" is "oxygen saturation"... pulse oxygen, "pulse ox", that little cute red light thing they put on your finger? Yeah, the "Pulse Oximeter".

Po2 is partial pressure of oxygen.

oxygen saturation is the not same and yes its read by a pulse oximeter.


i would like to clarify that cyanosis develops only in severe life threatening cases of asthma or acute severe asthma

nismaratwork Feb15-11 10:28 AM

Re: How does asthma lead to cyanosis?
 
Quote:

Quote by thorium1010 (Post 3138929)
Po2 is partial pressure of oxygen.

oxygen saturation is the not same and yes its read by a pulse oximeter.


i would like to clarify that cyanosis develops only in severe life threatening cases of asthma or acute severe asthma

re bold: That is EXACTLY what mtc said, and you argued with.

Quote:

Quote by thorium1010
Quote:

Quote by mtc
Incidentally asthmatics are generally not oxygen limited - it is a sign of severe ER requiring asthma if you see a change in blood PO2.
Again - most asthmatics are not hypoxic. This is a severe life threatening situation when an astrhmatic does develop low PO2.


This is not correct . Asthmatics , during an attack of asthma are hypoxic (depending on severity).

most of the cases are mild to moderate form and are usually reversible by drugs

Lovely, we all agree then.


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