Acid-Base Balance

Question 1

What is the concentration of H+ ions in the plasma?

Answer 1

35.5-44.5 nmol/L

Question 2

Why does acid production not deplete HCO3- ?

Answer 2

Kidneys recover all HCO3, PCT makes it from amino acids, and DCT makes it from CO2 and H2O

Question 3

How does HCO3- move from filtrate back into blood?

Answer 3

It reacts with H+, water and carbon dioxide move in to the cell, they react to reform HCO3- which is moved into the ECF via a Na HCO3- symporter

Question 4

How is HCO3- made in the PCT?

Answer 4

Glutamine breaks down into ammonium and alpha ketogluterate. Alpha ketoglutarate becomes HCO3-.

Question 5

How are H+ ions buffered in the lumen of DCT?

Answer 5

They react with hydrogen phosphate to form di hydrogen phosphate

Question 6

What is the minimum pH of urine?

Answer 6

4.5

Question 7

What is the total acid excretion per day?

Answer 7

50-100 mmol

Question 8

What happens to Potassium when there is acidosis?

Answer 8

Hyperkalaemia, K moves out of cells and there is reduced excretion

Question 9

What happens to Potassium when there is alkalosis?

Answer 9

Hypokalaemia, K moves into cells and there is enhanced excretion

Question 10

What kind of acid-base balance does hyperkalaemia cause?

Answer 10

Metabolic acidosis

Question 11

What kind of acid-base balance does Hypokalaemia cause ?

Answer 11

Metabolic alkalosis

Question 12

Which organ compensates for respiratory acidosis or alkalosis?

Answer 12

Kidney

Question 13

Why is pCO2 not raised in metabolic acidosis?

Answer 13

Extra CO2 is breathed off

Question 14

What is the normal Anion gap?

Answer 14

10-18 nmol/L

Question 15

What is the anion gap?

Answer 15

The difference between measured cations and anions

Question 16

Name 3 conditions that can cause type 2 respiratory acidosis?

Answer 16

Severe COPD, Severe Asthma, Drug overdose, Neuromuscular disease

Question 17

Name a condition that can cause respiratory alkalosis?

Answer 17

Hyperventilation, anxiety/panic attacks