A 64-year-old man with multilobar pneumonia and sepsis presents with hypoxemic respiratory failure requiring intubation. Vital signs: BP 92/58, HR 118, RR 32, Temp 39.2°C, SpO2 88%. Arterial blood gas shows pH 7.36, PaCO2 20 mm Hg, HCO3− 11 mEq/L. Serum lactate is 8.2 mg/dL (markedly elevated); creatinine is normal. He denies recent medication use. Which acid-base disturbance best characterizes his current status?

  1. A)Mixed respiratory alkalosis and metabolic acidosisGABARITO
  2. B)Mixed respiratory acidosis and metabolic acidosis
  3. C)Pure metabolic alkalosis
  4. D)Pure respiratory alkalosis
  5. E)Pure metabolic acidosis with appropriate compensation

Explicação

Sepsis commonly produces lactic acidosis, causing a metabolic acidosis, and can simultaneously trigger marked hyperventilation, causing respiratory alkalosis. The bicarbonate is very low, and the PaCO2 is lower than predicted by Winter formula, indicating a mi... Ver explicação completa e trilha adaptativa →

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