Acid Base Handling

Question 1

How is respiration controlled?

Answer 1

Chemoreceptors in the hypothalamic respiratory centre

Question 2

What is the main abnormality in metabolic acidosis?

Answer 2

Increased hydrogen ions and decreased bicarbonate

Question 3

What can cause metabolic acidosis?

Answer 3

Increased hydrogen ion production = DKA
Decreased hydrogen ion excretion = renal tubular acidosis
Bicarbonate loss = intestinal fistula

Question 4

How does the body compensate for metabolic acidosis?

Answer 4

Increasing respiratory rate to blow off carbon dioxide

In compensated metabolic acidosis, pCO2 will be LOW

Question 5

What is the primary abnormality in respiratory acidosis?

Answer 5

Increased CO2 causing increased hydrogen ions, slightly increased bicarbonate

Question 6

Causes of respiratory acidosis?

Answer 6

Decreased ventilation
Poor lung perfusion
Impaired gas exchange

Question 7

What is the primary abnormality in metabolic alkalosis?

Answer 7

Decreased hydrogen ions and increased bicarbonate

Question 8

Causes of metabolic alkalosis?

Answer 8

Hydrogen ion loss
Hypokalaemia
Ingestion of bicarbonate

Question 9

What happens in compensation of metabolic alkalosis?

Answer 9

Respiratory centre will be inhibited leading to a rise in pCO2

Question 10

What is the main problem in respiratory alkalosis?

Answer 10

Low CO2

If prolonged, will result in low bicarbonate and decreased renal hydrogen ion excretion.

Question 11

Causes of respiratory alkalosis?

Answer 11

Hyperventilation:

• Voluntary
• Mechanical ventilation
• Stimulation of respiratory centre