Relative tidal volume and respiratory airflow estimation using tracheal sound and movement during sleep.

Relative tidal volume and respiratory airflow estimation using tracheal sound and movement during sleep. J Sleep Res. 2021 Feb 03;:e13279 Authors: Montazeri Ghahjaverestan N, Kabir MM, Saha S, Gavrilovic B, Zhu K, Taati B, Alshaer H, Yadollahi A Abstract Airflow is the reference signal to assess sleep respiratory disorders, such as sleep apnea. Previous studies estimated airflow using tracheal sounds in short segments with specific airflow rates, while requiring calibration or a few breaths for tuning the relationship between sound energy and airflow. Airflow-sound relationship can change by posture, sleep stage and airflow rate or tidal volume. We investigated the possibility of estimating surrogates of tidal volume without calibration in the adult sleep apnea population using tracheal sounds and movements. Two surrogates of tidal volume: thoracoabdominal range of sum movement and airflow level were estimated. Linear regression was used to estimate thoracoabdominal range of sum movement from sound energy and the range of movements. The sound energy lower envelope was found to correlate with airflow level. The agreement between reference and estimated signals was assessed by repeated-measure correlation analysis. The estimated tidal volumes were used to estimate the airflow signal. Sixty-one participants (30 females, age: 51 ± 16 years, body mass index: 29.5 ± 6.4 kg m-2 , and apnoea-hypopnea index: 20.2 ± 21.2) were i...
Source: Journal of Sleep Research - Category: Sleep Medicine Authors: Tags: J Sleep Res Source Type: research