A 42-year-old woman with poorly controlled type 2 diabetes mellitus presents to the emergency department with a 2-day history of polyuria, polydipsia, and progressive dyspnea. She reports fruity-smelling breath and denies fever or recent infections. On examination, she is alert but drowsy, breathing deeply and rapidly. Vital signs: BP 98/62 mmHg, HR 118 bpm, RR 28 breaths/min, temperature 37.2°C, SpO2 94% on room air. Arterial blood gas reveals pH 7.24, PCO2 22 mmHg, HCO3− 9 mEq/L. Serum glucose 487 mg/dL, serum β-hydroxybutyrate elevated, serum osmolality 318 mOsm/kg. Urinalysis shows 3+ glucose and 3+ ketones. Which of the following best describes the primary acid-base disturbance and respiratory response?

  1. A)Metabolic acidosis with inadequate respiratory compensation (PCO2 too high)
  2. B)Respiratory acidosis with metabolic compensation
  3. C)Mixed metabolic and respiratory acidosis
  4. D)Metabolic alkalosis with compensatory hyperventilation
  5. E)Metabolic acidosis with appropriate respiratory compensationGABARITO

Explicação

This patient has diabetic ketoacidosis (DKA) causing metabolic acidosis (pH 7.24, HCO3− 9). The respiratory system is appropriately compensating with hyperventilation (RR 28, PCO2 22). Using Winter's formula, expected PCO2 = 1.5 × HCO3− + (23 ± 2) = 1.5(9) + 2... Ver explicação completa e trilha adaptativa →

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