Asphyxia is best described as what combination?

• A. Hypoxia with metabolic acidosis
• B. Hyperoxia with metabolic alkalosis
• C. Hypoxemia with respiratory alkalosis
• D. Hypercapnia with metabolic acidosis

Answer: (A)

Asphyxia occurs when oxygen delivery to tissues is severely reduced. That lack of oxygen forces cells to switch to anaerobic metabolism, which produces lactic acid and causes metabolic acidosis. The defining feature here is hypoxia paired with metabolic acidosis, reflecting the lactic acid buildup from oxygen deprivation. While carbon dioxide can accumulate, the characteristic acid-base disturbance described with asphyxia is metabolic acidosis rather than a primary respiratory acidosis. The other options describe combinations that don’t align with the typical pathophysiology of asphyxia.