What does pO2 measure in the bloodstream?

pO2 measures the partial pressure of oxygen in the bloodstream, which is a critical parameter in assessing a patient's oxygenation status. It indicates how much oxygen is dissolved in the plasma portion of the blood, which is essential for understanding how well the lungs are transferring oxygen into the blood. pO2 is commonly measured through arterial blood gas analysis and is vital in diagnosing and managing respiratory conditions, as well as monitoring the effectiveness of oxygen therapy in various clinical situations. A normal pO2 range is indicative of optimal oxygen transport to tissues, while deviations from this range can signify hypoxemia or other respiratory issues.