Continuous respiratory monitoring for sleep apnea screening by ambulatory hemodynamic monitor

Figure 1 Placement of the recorder unit and the electrocardiography /sound sensors. Regular electrocardiography (ECG) monitoring electrodes are placed on the right arm (RA), left arm (LA) and left leg (LL) locations for ECG monitoring. Combined ECG/sound sensors are placed in the precordial V3 and V4 positions. The recorder unit is placed on the right upper chest wall.

Figure 2 Performance of sleep-disordered breathing severity score against polysomnography apnea/hypopnea index for categorizing subjects into mild, moderate or severe sleep apnea on test set data. Error bars show 95% confidence intervals. AHI: Apnea/hypopnea index.

Figure 3 Relationship of the automated respiration rate algorithm to the over-read respiration rate on test set data.