Arterial blood gas

Question 1

Define:

Answer 1

A blood test in which heparinised blood is usually taken from the radial or femoral artery

measures pH, PaCO2 and PaO2

Question 2

Indications:

Answer 2

Resp failure

Sepsis

severely unwell

heart, liver and renal failure

ventilated patients

indication of resp, metabolic or mixed acid base disorders

sleep studies

Question 3

complications:

Answer 3

infection

artery vasospasm

arterial occlusion

local haematoma

air embolism

Question 4

Define Type 1 resp failure:

Answer 4

hypoxia and normocapnia

Question 5

Define type 2 resp failure:

Answer 5

hypoxia and hypercapnia

Question 6

What are causes of resp acidosis:

Answer 6

resp depression

asthma

COPD

Gullian Barre

Question 7

What are causes of resp alkalosis:

Answer 7

Over ventilation:

• anxiety
• pain
• hypoxia
• PE
• pneumothorax

Question 8

What are causes of metabolic acidosis with an increased anion gap:

Answer 8

lactic acidosis - shock, tissue ischaemia and infection

Ketones - DM and alcohol

urate - renal failure

drug/toxins

Question 9

what are causes of metabolic acidosis with a normal anion gap:

Answer 9

renal tubular acidosis

diarrhoea

addison’s

Question 10

what are causes of metabolic alkalosis:

Answer 10

GI disturbances which mean loss of H+ such as vomiting

renal loss of H+ = loop or thiazide diuretics