What is the function of a thermistor in a sleep study?

The function of a thermistor in a sleep study is to monitor airflow based on temperature changes. A thermistor is a type of temperature sensor that is particularly sensitive to small changes in temperature. In the context of polysomnography, it is used to assess airflow during sleep by measuring the temperature of the air that is inhaled and exhaled.

When a person breathes, the thermistor detects the temperature differences associated with inhaling cooler air and exhaling warmer air, providing valuable data on breathing patterns. This information is crucial for identifying respiratory events such as apneas or hypopneas during the sleep study.

In contrast, measuring oxygen saturation is typically done with a pulse oximeter, while brain wave activity is monitored using electroencephalography (EEG), and heart rate variability is tracked through electrocardiography (ECG). These options do not utilize a thermistor, highlighting the specificity of the thermistor's role in assessing airflow changes through temperature measurements.