ABG interpretation

Question 1

5 step approach to reading ABG

Answer 1

1. How is the patient?
2. Hypoxia?
   Pa02 >10 kPa
3. Acidosis (pH <7.35) or alkalosis (pH >7.45)
4. Respiratory component:
   PaCO2 > 6.0 kPa suggests a respiratory acidosis (or respiratory compensation for a metabolic alkalosis)
   PaCO2 < 4.7 kPa suggests a respiratory alkalosis (or respiratory compensation for a metabolic acidosis)
5. Metabolic component:
   bicarbonate < 22 mmol/l (or a base excess < - 2mmol/l) suggests a metabolic acidosis (or renal compensation for a respiratory alkalosis)
   bicarbonate > 26 mmol/l (or a base excess > + 2mmol/l) suggests a metabolic alkalosis (or renal compensation for a respiratory acidosis)