Acid-Base Disorders USMLE Step 1 Practice Question
A 67-year-old man is admitted with septic shock from pneumonia. He is confused and tachypneic. Arterial blood gas shows pH 7.19, PaCO2 28 mm Hg, and HCO3− 11 mEq/L. Serum electrolytes show Na+ 140 mEq/L, Cl− 100 mEq/L, and HCO3− 11 mEq/L. Which of the following is this patient's anion gap?
Answer choices
- A29 mEq/LCorrect answer
- B51 mEq/L
- C40 mEq/L
- D11 mEq/L
- E18 mEq/L
- F35 mEq/L
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