Acid Base disorders Renal

Question 1

What is the Henderson hasselbalch equation for the Bicarbonate buffer system?

Answer 1

pH = 6.1 + log([HCO3-]/(0.03)Pco2

Question 2

How is Acid formed from the food we eat?

Answer 2

Oxid of Nutr => CO2 => Carbonic Acid
Ox of Met/Cys => Sulferic Acid
Ox of Phos compounds => Phosphoric Acid

Question 3

How is Base formed from the food we eat?

Answer 3

Mets of Glut/Aspartate and Org ions => base

Question 4

How is Resp Compensation Mediated?

Answer 4

Hypo or Hyperventilationreg Pco2

RAPID

Question 5

How does Resp Compensation Mediated?

Answer 5

Reg of HCO3- concentration
Reg of H+ excretion
SLOW

Question 6

How does the kidney effect serum pH?

Answer 6

Regulate H+ excretion and HCO3 Reabsorption

Question 7

What is the process of Proximal Acidification?

Answer 7

Na/H+ transporter pumps H+ out

Na/K ATP transporter maintains the gradient

Question 8

What is the process of Distal Acidification?

Answer 8

H+ ATP pump moves H+ directly into the Tubular Lumen

Question 9

What stimulates Insertion of ATPase into luminal membrane?

Answer 9

LOW pH

Question 10

What stimulates Recycling of ATPase back into cytoplasm?

Answer 10

HIGH pH

Question 11

What is the process of Resorption of Bicarbonate in the Prox Tubule?

Answer 11

H+ secreted into the tub lumen
Rx with HCO3 in filt => CarbH+
Carb anhydrase Conv to H20 and CO2
H20 andCO2 diffuse into renal tubular Cell
Carb Anhydrase conv H20 and CO2 to Carb acid
Carb acid dissociates, H+ exported to tubule lumen and HCO3 exported to blood

Question 12

What is the Net Effect of Reabsorption of Bicarb in Prox tubule?

Answer 12

Movement of NaHCO3 from filtrate to the Blood

Question 13

What is the lowest that the Urine pH can Go? Limiting urine pH.

Answer 13

4.4

Question 14

What is the Exchange rate of newly formed H2PO4- excreted in the Urine?

Answer 14

One H+ elininated

One NEW HCO3- formed and added to the blood

Question 15

What is Titratable Acid?

Answer 15

Measure of H+ excreted in urine as un-dissociated weak acid and H2PO4- Most abundant

Question 16

How is Titratable acid level Determined?

Answer 16

24hr urine collection

measure NaOH required to back-titrate urine pH to 7.4

Question 17

What is the role of Glutaminase?

Answer 17

Converts glutamine to glutamate
Glutamate converted to a-KG by glutamate dehydrogenase
Glut mets YIELDS 2HCO3

Question 18

What happens to Regulation of H+ Excretion during acidosis?

Answer 18

H+ secretion increased
All HCO3- Reabsorbed
Substantial titratable acid excreted
NH4+ production increased
-inc glutamine uptake/glutaminase activity
-inc NH4+ excretion in urine

Question 19

What happens to Regulation of H+ Excretion during Alkalosis?

Answer 19

H+ Secretion insufficient to allow HCO3- reabsorption
-HCO3 secreted in urine
B-Type intercalated cells of collecting duct secrete Bicarb into Tubular Lumen
No Titr Acid or Ammonium ions excreted in urine

Question 20

What is the normal value for arterial Pco2?

Answer 20

40 Torr

Question 21

What is the normal value for arterial pH?

Answer 21

7,35 to 7.45

Question 22

What is the normal value for arterial Bicarb?

Answer 22

24mmol/L

Question 23

What is the normal value for urinary Titratible Acid?

Answer 23

0-20 mmol/day

Question 24

What is the normal value for urinary ammonium ion?

Answer 24

20-40 mEq/day

Question 25

What is the normal value for Anion Gap?

Answer 25

8-12 mEq/L