Acid-Base Disorders USMLE Step 1 Practice Question
A 73-year-old woman is admitted for septic shock due to pyelonephritis. Blood pressure is 78/40 mm Hg despite fluid resuscitation. She is cool and confused. Arterial blood gas shows pH 7.21 and bicarbonate 12 mEq/L. Which of the following is the most likely source of the acid load in this patient?
Answer choices
- ALoss of gastric hydrochloric acid
- BLactic acid production from tissue hypoperfusionCorrect answer
- CFormic acid accumulation
- DRenal bicarbonate wasting due to aldosterone excess
- EHyperventilation-induced carbonic acid loss
- FKetoacid accumulation from hepatic gluconeolysis impairment
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