Table 1 Apnea and arousal definitions used in the current study.
Apnea | Definition | Duration |
|---|---|---|
Central apnea | Apnea with no breathing movements | Pause in breathing lasting: >2 breathing cycles and ≥4 s |
Obstructive apnea | Apneas with breathing movements but no airflow | All obstructive pauses of breathing |
Mixed apnea | Apneas commencing as central but showed obstructive respiratory movements | All mixed apneas |
Apnea of prematurity | Apnea with: Heart rate decrease to <100 beats per minute, or drop in SpO2 to <80%, or apnea length of >20 s | |
Arousal | Definition | Duration |
Arousal | A sustained increase in chin and diaphragm EMG from baseline recording excluding sucking of the dummy, or gross body movements causing artefacts in ECG, EEG, respiratory signal | ≥3 s |
Apnea arousal | An arousal appearing during an apnea, or within 5 s after the end of an apnea | ≥3 s |
Long arousal or awakening | Same as arousal | ≥15 s |
