Can someone explain to me this first aid concept

[step1april2013]

in FA 2012 on pg. 300 it states that the dyspnea on exertion seen in CHF is caused by a failure of CO2 to increase during exercise.

I thought an increase in CO2 would cause dyspnea instead of a decrease.

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[step1april2013]

Could it possibly be from a lack of CO2 that would have otherwise caused autoregulatory dilation of the coronary arteries? But wouldn't this theory cause chest pain instead?

 

[bangarang]

in FA 2012 on pg. 300 it states that the dyspnea on exertion seen in CHF is caused by a failure of CO2 to increase during exercise.

I thought an increase in CO2 would cause dyspnea instead of a decrease.

It says CO, which refers to cardiac output.

 

[step1april2013]

It says CO, which refers to cardiac output.

Thats before errata revision. The errata changed CO to CO2

 

[addo]

Im not sure, but i think chf would decrease oxygen delivery and thereby oxidative phosphorylation causing a decrease in co2. CO2 causes pulmonary vasdialation which is unique to this vasculature. Blood flow to coronaries are regulated by metabolites, principally adenosine. Decreased co2 would alsoincrease ph and decrease drive to ventilate by central chemoreceptors

 

[step1april2013]

Im not sure, but i think chf would decrease oxygen delivery and thereby oxidative phosphorylation causing a decrease in co2. CO2 causes pulmonary vasdialation which is unique to this vasculature. Blood flow to coronaries are regulated by metabolites, principally adenosine. Decreased co2 would alsoincrease ph and decrease drive to ventilate by central chemoreceptors

I appreciate the response, so by decreasing CO2 there is dyspnea because of a decreased drive to ventilate. I'm not sure about the oxidative phosphorylation explaination only because the end product of it is water. However, TCA does create CO2, so I think that explains it better.

 

[addo]

The tca cycle and oxidative phosphorylation are tightly linked. You cant either without the other. Without oxidative phosphorylation you would just have a build up of reduced factors and a switch to anaerobic metabolism. But youre right the tca cycle makea the co2 and the end product of ox. Phosph is h20

 

[step1april2013]

The tca cycle and oxidative phosphorylation are tightly linked. You cant either without the other. Without oxidative phosphorylation you would just have a build up of reduced factors and a switch to anaerobic metabolism. But youre right the tca cycle makea the co2 and the end product of ox. Phosph is h20

Alright, appreciate the help. Good luck with your studies!

 

[teratomas]

i Dont think that is right because whenever you dec Po2, you will inc Pco2 to maintain the partial pressure of gasses.

 

[addo]

i Dont think that is right because whenever you dec Po2, you will inc Pco2 to maintain the partial pressure of gasses.

isnt the partial pressure independent of blood oxygen and co2 carrying capacity? In other words you can have normal partial pressures of gases in blood but they contribute little to respiration as RBCs carry most of the oxygen and co2