clinical acid base disorders

Question 1

what can cause respiratory alkalosis?

Answer 1

overbreathing
o Any cause of impaired oxygenation
o Central cerebral stimulation: fever, pain, drugs, sepsis, Panic/anxiety

Question 2

what does COPD lead to?

Answer 2

decreased sensitivity to CO2 (they become accustomed to high pCO2 over time bc the disease is chronic)

Question 3

what causes respiratory acidosis?

Answer 3

anything that causes reduced ventilation

o Airway disease; neuromuscular or chest wall disease; reduced respiratory drive: opiates or reduced consciousness

Question 4

what are the 2 main causes of metabolic acidosis?

Answer 4

either adding acid or losing bicarbonate

Question 5

how do you distinguish between the causes of metabolic acidosis?

Answer 5

use the anion gap

Question 6

what are the causes of high anion gap metabolic acidosis?

Answer 6

Ketones: DKA and Starvation or alcoholic ketoacidosis
Lactate:
o Tissue hypoxia/poor perfusion
o Altered cellular respiration
o Rarely: D-lactate
‘Titrable acid’ - Renal failure acidosis – failure to clear titrable acid using phosphate/ammonium
• Ingested acid - Ethylene glycol, methanol, salicylate

Question 7

what causes ketoacidosis?

Answer 7

impaired oxygenation or glucose entry

Question 8

what are the types of renal tubular acidosis?

Answer 8

• Type 1 – distal
• Type 2 – proximal
• Type 3 – very rare
• Type 4 – hyperkalaemic

Question 9

what are the causes of acidosis due to gut losses?

Answer 9

diarrhoea (lose bare bicarbonate), external drainage of pancreas/biliary tree, urinary diversion

Question 10

what are the acute consequences of acidosis?

Answer 10

o Negative inotropic effects
o Confusion
o Kussmaul’s breathing
o Hyperkalaemia

Question 11

what are the chronic consequences of acidosis?

Answer 11

o Bone reabsorption, calciuria, stones
o Insulin resistance
o Progressive renal impairment