Acid-Base Disorders USMLE Step 1 Practice Question
A 20-year-old college student comes to the emergency department because of chest tightness, dizziness, and tingling in both hands that began during an exam. She is visibly anxious and breathing rapidly. Arterial blood gas shows pH 7.55, PaCO2 25 mm Hg, and HCO3− 22 mEq/L. Which of the following acid-base disorders is most likely present?
Answer choices
- AAcute respiratory acidosis
- BAnion gap metabolic acidosis
- CMetabolic alkalosis
- DAcute respiratory alkalosisCorrect answer
- EChronic respiratory alkalosis
- FAnion gap metabolic alkalosis
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