Asthma affects about seven percent of the population. During an asthma attack smooth muscle cells in the bronchi constrict, the airways become inflamed and swollen, and breathing becomes difficult. What effect might an asthma attack have on blood pH?

Question

Asthma affects about seven percent of the population.  During an asthma attack smooth muscle cells in the bronchi constrict, the airways become inflamed and swollen, and breathing becomes difficult. What effect might an asthma attack have on blood pH?

A. pH goes down
B. pH goes up
C. No change in blood pH

My first instinct is to guess that the pH will go down because pCO2 will rise. However some stuff that I have read says that the blood pH rises initially--so I am unsure of the overall effect on blood pH. I am still fairly certain it's A, but would just like some confirmation?

DrBob222 · Answer

H2O + CO2 <==> H2CO3 <==> H^+ + HCO3^-
So if we restrict the breathing, CO2 rises, and Le Chatelier's Principle says that will force the reaction to the right; therefore, my best guess is that the blood pH will decrease (become more acid).