A 25-year-old woman has dyspnoea, pleuritic pain and a unilateral swollen calf after a long flight. Which finding on arterial blood gas is typical?
Answer and explanation
Correct answer: D. Hypoxaemia with respiratory alkalosis
- Step 1: Pulmonary embolism causes hyperventilation, so PaCO2 falls. Answer: Hypoxaemia with respiratory alkalosis. Why not the others: Hypercapnia with respiratory acidosis, Metabolic acidosis with hypercapnia and Metabolic alkalosis with hypocapnia don't fit.
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