Figure 1. Recurrence of Cheyne-Stokes respiration with periodic oxyhemoglobin desaturations and transient arousals following the cessation of phrenic nerve stimulation.

The preprogrammed cessation of phrenic nerve stimulation at 6:00 am (see vertical line) resulted in the prompt recurrence of Cheyne-Stokes respiration with periodic oxyhemoglobin desaturations and transient arousals from sleep (not shown). Rhythmic stimulation bursts are seen in ECG signal during the Therapy On segment (left side) but not during the Therapy Off segment (right side). Occasional movement artifacts appear in the first several minutes of the Therapy On period. Signals include ECG, SpO₂ (pulse oximetry, %), airflow (nasal pressure cannula), and thoracic and abdominal piezoelectric girth sensors. ECG = electrocardiogram; SpO₂ = peripheral oxygen saturation.