What are the filter settings for respiratory effort and airflow in polysomnography?

The appropriate filter settings for respiratory effort and airflow in polysomnography are critical for accurately assessing the patient's respiratory patterns during sleep. Low-frequency filters (LFF) help to eliminate unwanted drift and baseline wander in signals, while high-frequency filters (HFF) are used to reduce noise and artifacts, which can obscure important respiratory signals.

The correct settings of LFF = 0.1 Hz and HFF = 15 Hz allow for the detection of the low-frequency components associated with respiratory effort, such as chest and abdominal movements, while still capturing the higher frequency components related to airflow measurement without distortion. This balance is necessary for clear and interpretable respiratory data, ensuring that subtle changes in respiratory patterns can be accurately captured and analyzed.

Appropriate filter settings are crucial because incorrect settings can lead to misinterpretation of respiratory events, affecting the overall evaluation of the patient’s sleep study results. Therefore, option C, with its specific range of frequencies, supports optimal data collection for respiratory analysis in polysomnography.