Which tool is primarily used to measure oxygen saturation during sleep studies?

The pulse oximeter is the primary tool used to measure oxygen saturation during sleep studies. This device works by using light sensors to evaluate the percentage of hemoglobin in the blood that is saturated with oxygen. It provides real-time data that is crucial for assessing a patient's oxygen levels throughout the night, particularly in conditions like obstructive sleep apnea, where intermittent breathing disruptions can occur.

Measuring oxygen saturation is vital for determining the efficiency of the respiratory system during sleep. The pulse oximeter's ability to non-invasively monitor this vital sign makes it an essential instrument in polysomnography. It can help identify desaturation events that may occur as a result of apneas, hypopneas, or other sleep-related breathing disorders.

Other devices, while useful in their own contexts, do not serve this specific purpose. For instance, an electrode array is primarily used for recording brain activity (EEG), the blood pressure cuff measures arterial pressure, and a capnometer assesses carbon dioxide levels in the breath. Each of these has its own merits in various clinical settings but does not measure oxygen saturation directly as the pulse oximeter does.