Final answer:
Sodium bicarbonate neutralizes TCA-induced acidosis during a TCA overdose by acting as a buffer to reduce excess acidity in the blood, aiding in the management of cardiovascular and central nervous system symptoms. The option (C) is correct.
Step-by-step explanation:
The mechanism of action of sodium bicarb, or sodium bicarbonate, in the treatment of tricyclic antidepressant (TCA) overdose is to neutralize TCA-induced acidosis. When TCAs cause a systemic toxic effect, one of the major concerns is the development of acidosis, which sodium bicarbonate can help to mitigate. Sodium bicarbonate does this by acting as a buffer to neutralize excess acidity in the blood. This in turn can help to improve the cardiovascular and central nervous system symptoms associated with TCA toxicity. Recovery of bicarbonate ions is vital to maintaining acid-base balance since it is a very powerful and fast-acting buffer. By providing bicarbonate, we replenish these ions, helping to counter the acidosis caused by the overdose.
Acidosis refers to a state of increased acidity in the body’s fluids and is precisely what sodium bicarbonate aims to correct in the case of TCA overdose. Therefore, option (C) is correct.