A 38-year-old woman presents with acute dyspnea and pleuritic chest pain after a 12-hour international flight. Vital signs: BP 128/82, HR 102, RR 22, SpO2 91% on room air, temperature 37.2°C. Arterial blood gas shows pH 7.48, PaCO2 30 mmHg, PaO2 72 mmHg, HCO3 22 mEq/L. Chest X-ray is normal. She denies leg swelling. Which acid-base disturbance is present, and what condition does it suggest?

  1. A)Acute respiratory alkalosis, consistent with pulmonary embolismGABARITO
  2. B)Chronic respiratory alkalosis, consistent with high-altitude exposure
  3. C)Acute respiratory acidosis, consistent with COPD exacerbation
  4. D)Mixed metabolic alkalosis and respiratory acidosis, consistent with vomiting with COPD
  5. E)Metabolic acidosis, consistent with sepsis

Explicação

The ABG shows a low PaCO2 (30 mmHg) with a high pH (7.48) and normal bicarbonate (22 mEq/L), indicating acute respiratory alkalosis. This pattern is classic for PE: tachypnea driven by hypoxemia and dead space ventilation causes CO2 washout. The history of pro... Ver explicação completa e trilha adaptativa →

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