How does the body initially compensate for metabolic acidosis?

How does the body initially compensate for metabolic acidosis?

• A. Increase bicarbonate production
• B. Exhale more CO2
• C. Increase renal excretion of hydrogen
• D. Decrease respiration

Answer: (B)

Metabolic acidosis prompts an immediate respiratory compensation: you increase ventilation to blow off more carbon dioxide. This lowers PaCO2, shifting the bicarbonate buffering reaction toward fewer hydrogen ions and helping raise pH toward normal. The drive comes from chemoreceptors sensing the acidosis and CO2 changes, producing faster, deeper breathing (often seen as rapid, labored breaths). Renal adjustments—excreting hydrogen or generating new bicarbonate—take longer to develop, and decreasing respiration would worsen acidosis. So exhaling more CO2 is the quickest, primary way the body compensates initially.

Metabolic acidosis prompts an immediate respiratory compensation: you increase ventilation to blow off more carbon dioxide. This lowers PaCO2, shifting the bicarbonate buffering reaction toward fewer hydrogen ions and helping raise pH toward normal. The drive comes from chemoreceptors sensing the acidosis and CO2 changes, producing faster, deeper breathing (often seen as rapid, labored breaths). Renal adjustments—excreting hydrogen or generating new bicarbonate—take longer to develop, and decreasing respiration would worsen acidosis. So exhaling more CO2 is the quickest, primary way the body compensates initially.