Which agent is used to correct metabolic acidosis during anesthesia?

• A. Sodium bicarbonate
• B. Lidocaine
• C. Atropine
• D. Adrenaline

Answer: (A)

Sodium bicarbonate is used to correct metabolic acidosis because it provides buffering capacity to neutralize excess hydrogen ions. When bicarbonate ions bind hydrogen ions, they form carbonic acid, which quickly becomes carbon dioxide and water. In a patient under anesthesia with a controlled airway and ventilation, the CO2 produced can be effectively removed by the ventilator, allowing the pH to rise toward normal.

This approach is especially considered in severe metabolic acidosis or when there is a significant base deficit. Administration must be careful—overcorrection or rapid shifts can cause alkalosis, and the patient’s fluid and sodium balance must be monitored since bicarbonate adds sodium and can expand the extracellular fluid compartment.

The other agents do not correct metabolic acidosis: they have roles such as local anesthesia, heart rate/bronchodilation management, or vasopressor effects, not buffering the excess hydrogen ions or raising the pH.