Which acid-base disturbance is commonly seen in aspirin overdose?

Which acid-base disturbance is commonly seen in aspirin overdose?

• A. Metabolic acidosis
• B. Metabolic alkalosis
• C. Respiratory alkalosis
• D. No disturbance

Answer: (C)

When aspirin overdose occurs, the first and most characteristic change is stimulation of the respiratory center in the brain, which causes hyperventilation. This rapid breathing blows off CO2, producing a respiratory alkalosis. Early on, you may see a low PaCO2 with a near-normal or slightly elevated pH. As salicylate levels rise, the drug also disrupts cellular metabolism and promotes the production of organic acids, leading to metabolic acidosis. Because both processes can be present, some patients have a mixed picture, but the initial and most commonly observed disturbance is respiratory alkalosis due to the drug’s effect on respiration.

When aspirin overdose occurs, the first and most characteristic change is stimulation of the respiratory center in the brain, which causes hyperventilation. This rapid breathing blows off CO2, producing a respiratory alkalosis. Early on, you may see a low PaCO2 with a near-normal or slightly elevated pH. As salicylate levels rise, the drug also disrupts cellular metabolism and promotes the production of organic acids, leading to metabolic acidosis. Because both processes can be present, some patients have a mixed picture, but the initial and most commonly observed disturbance is respiratory alkalosis due to the drug’s effect on respiration.