For a basic approach to blood gas interpretation see here
1. What is the Acid-Base distrubance?
pH = 7.341 ∴ slight acidosis
Cause of acidosis?
Is there appropriate respiratory compensation or a concomitant process?
What is the cause of the metabolic acidosis?
Overall: NAGMA with mild respiratory alkalosis
Cause of acidosis?
- CO2 = 30.0 ∴ Primary Metabolic Acidosis
Is there appropriate respiratory compensation or a concomitant process?
- Expected CO2 = 1.5 x HCO3 + 8 = 33.65
- Actual CO2 = 27.6 ∴ concomitant mild respiratory alkalosis
What is the cause of the metabolic acidosis?
- Anion Gap = 133 - 17.1 - 107 = 8.9 = NAGMA (Normal = 12 +/- 4)
Overall: NAGMA with mild respiratory alkalosis
2. Are there any electrolyte issues?
Na (for glc)
K (for pH)
Ca (for alb)
- Since Glc is normal, we don't really need to check - we know its as read
- Actual Na - mNa + (Glc - 5)/3 = 133 + (6.3 - 5)/3 = 133.4
- ∴ Normonatraemic
K (for pH)
- Expected K = 5(7.4 - pH) +5 = 5(7.4 - 7.341) + 5 = 5.1
- Actual K = 6.7 ∴ Hyperkalaemic
Ca (for alb)
- Ca = 1.11 corrected on gas
3. Are there any oxygenation issues?
This is a venous sample ∴ unable to calculate
4. Are there any other abnormalities?
COHb & MetHb normal