Acid Base Physiology

Question 1

Normal pH of arterial blood

Answer 1

7.40 +/- 0.02

Question 2

Difference of pH in arterial blood vs venous blood

Answer 2

More CO2 in venous blood, more acidic

Urine is acidic
GI, most acidic

Question 3

Chemical Buffer Systems

Answer 3

Mixtures that minimize changes in pH brought about by the addition of acids or basis
Bicarb
Phosphate
Ammonia
Proteins

Question 4

Modified pH

Answer 4

PH= 6.1 + log ([HCO3]/ 0.03 X Pco2)

Question 5

Clinical HHE

Answer 5

[H+]=24 X {[PaCO2]/[HCO3-]}

[H+] = 80 -pH.xx

+/-2

Question 6

CO2 removal and pH

Answer 6

CO2 removal decreases, ventilation decreases, volume of CO2 expired decreases, increasing percent CO2 in arteries, decreasing pH (increasing H)–more acidic

Question 7

CO2 production and pH

Answer 7

CO2 production less than removal, increased ventilation, increased expired CO2, decreased CO2 in arteries, increase pH (decreased H+)—alkalosis

Question 8

Doubling and halving ventilation, effects on pH

Answer 8

Double ventilation, more CO2 removed, alkalosis, pH increases about .23

Halving ventilation, less CO2 removed, acidosis, pH decreases about 0.29

Question 9

Decrease in pH pathway with respiratory response

Answer 9

Never back to 100% due to feedback inhibition of the chemoreceptors by the newly increased pH

Decrease pH, stimulation of chemoreceptors, increase ventilation of CO2, decrease arterial CO2, increase pH (lowering H+)

Question 10

Respiratory compensation responses to acid-base challenges

Answer 10

increase [H+] (becoming acidic) stimulates carotid bodies to increase ventilation to decrease PaCO2.
The decrease in PaCO2 feedback inhibits the carotid bodies.
The decrease in PaCO2 stimulates the central chemoreceptors and decrease ventilation.

Question 11

urine and body pH

Answer 11

If body pH decreases, more acidic urine
If body pH increases, more alkaline urine

Kidney inserts proteins into membrane to fully compensate
Secrete acid or reabsorb bicarbonate or make new bicarb

Question 12

Normal Hydrogen ion concentration in body fluids

Answer 12

40 nEq/L