Excessive vomiting causes which acid-base disturbance?

Excessive vomiting causes which acid-base disturbance?

• A. Metabolic acidosis
• B. Metabolic alkalosis
• C. Respiratory acidosis
• D. Respiratory alkalosis

Answer: (B)

Excessive vomiting removes acid from the body. Stomach contents are rich in hydrogen ions (HCl), so losing them leaves the remaining body fluids comparatively alkaline. The drop in hydrogen ions, along with chloride loss and volume depletion, drives the kidneys to retain bicarbonate, reinforcing a metabolic alkalosis. The respiratory system then responds by hypoventilating to raise carbon dioxide and partially offset the higher pH, but this is a compensatory change, not the primary disturbance. So the main acid-base change from excessive vomiting is metabolic alkalosis.

Excessive vomiting removes acid from the body. Stomach contents are rich in hydrogen ions (HCl), so losing them leaves the remaining body fluids comparatively alkaline. The drop in hydrogen ions, along with chloride loss and volume depletion, drives the kidneys to retain bicarbonate, reinforcing a metabolic alkalosis. The respiratory system then responds by hypoventilating to raise carbon dioxide and partially offset the higher pH, but this is a compensatory change, not the primary disturbance. So the main acid-base change from excessive vomiting is metabolic alkalosis.