Acidosis occurs when shock leads to buildup of which substance in tissue?

• A. Bicarbonate
• B. Lactic acid
• C. Oxygen
• D. Sodium

Answer: (B)

When tissue perfusion drops during shock, cells can’t rely on oxygen-dependent (aerobic) metabolism. They switch to anaerobic glycolysis, which produces lactate (lactic acid) and free hydrogen ions. The buildup of lactate and the accompanying hydrogen ions lower the tissue and blood pH, causing acidosis. Bicarbonate acts as a buffer and is used up to neutralize the excess hydrogen ions, so its presence isn’t the source of acidosis. Oxygen would be scarce, not accumulating, and sodium isn’t directly involved in causing acidosis in this context.