What is the primary metabolic disturbance caused by salicylate overdose?

In salicylate overdose, the primary metabolic disturbance is metabolic acidosis. Initially, salicylates stimulate the respiratory center, leading to hyperventilation and resultant respiratory alkalosis. However, as the overdose progresses, the accumulation of salicylic acid results in an increased anion gap metabolic acidosis due to the production of organic acids and the impairment of cellular metabolism.

The key factor in this progression is that salicylates interfere with the normal metabolic process, leading to the production of lactic acid and decreased ability of the body to buffer acids effectively. The combination of these acidosis effects and respiratory compensation creates a complex acid-base imbalance that commonly includes metabolic acidosis.

While respiratory alkalosis occurs initially, it is ultimately overshadowed by the more significant metabolic acidosis as the overdose progresses. Thus, the correct answer highlights the primary final outcome in the context of salicylate toxicity, which is metabolic acidosis, predominantly characterized by an increase in the anion gap.