What is the normal partial pressure of oxygen (paO2) in arterial blood?

The normal partial pressure of oxygen (PaO2) in arterial blood typically ranges from 75 to 100 mmHg. This range reflects the amount of oxygen that is dissolved in the plasma and is an important indicator of how well oxygen is being absorbed from the lungs into the bloodstream.

Maintaining a PaO2 within this range is crucial for efficient oxygen delivery to tissues throughout the body. Values below this range may indicate hypoxemia, which can lead to inadequate oxygenation of tissues and organs, while values above this range are less common but can occur in certain clinical situations, such as hyperoxia.

The ranges provided in the other options either overestimate or underestimate the normal PaO2 values, making them less accurate representations of typical physiological values. The widely accepted clinical standard supports the range of 75-100 mmHg, which is essential for proper respiratory function and overall metabolic processes in the body.