Hyperventilation results in a lack of which gas?

Hyperventilation leads to a decrease in carbon dioxide levels in the blood, a condition known as respiratory alkalosis. When a person hyperventilates, they exhale carbon dioxide at a rate that exceeds the body's production of it, resulting in a significant drop in arterial carbon dioxide (PaCO2) levels. Normally, carbon dioxide is a byproduct of cellular respiration and is maintained in the blood to help regulate pH among other physiological functions.

As carbon dioxide levels decrease, the body's pH rises, leading to symptoms such as lightheadedness, tingling in the extremities, and even loss of consciousness in severe cases. While oxygen levels may also be affected due to changes in breathing patterns, the primary concern with hyperventilation is the excessive loss of carbon dioxide rather than a lack of oxygen. In fact, the body often has sufficient oxygen reserves during hyperventilation despite reduced carbon dioxide levels.

Thus, the correct answer highlights the key issue associated with hyperventilation, focusing on carbon dioxide loss rather than other gases or hydration status.