Which term describes excessive ventilation?

• A. Hypoxia
• B. Hyperventilation
• C. Circulatory System
• D. Hypercapnia

Answer: (B)

Excessive ventilation means breathing that is more rapid or deeper than the body's needs for gas exchange. When this happens, carbon dioxide is expelled faster than it’s produced, leading to a drop in arterial CO2 (hypocapnia). That decrease in CO2 reduces hydrogen ion concentration, raising the blood’s pH and potentially causing respiratory alkalosis. The term that best describes this pattern is hyperventilation. It’s important to differentiate it from hypoxia, which is a lack of oxygen, and hypercapnia, which is an excess of carbon dioxide. The circulatory system isn’t what defines this, since the issue is the rate and depth of breathing rather than gas transport. Common signs of hyperventilation include dizziness, tingling, and lightheadedness due to the brain’s response to falling CO2 levels.