Automatic analysis of static charge sensitive bed (SCSB) recordings in the evaluation of sleep-related apneas.

An automatic analysis of Static Charge Sensitive Bed (SCSB) recordings was evaluated in the detecting periodic apneas during sleep. The results of over-night SCSB recordings, on body movements and respiratory movements, were compared with the visually evaluated polygraphic recordings during daytime sleep. Twenty-one patients with obstructive sleep apnea syndrome and 18 controls were studied. The periodic breathing pattern seen in all daytime recordings, was also seen in all output graphs of the over-night SCSB analyses. The automatic analyses revealed periodic breathing in 2 control subjects. The amount was, however, small (less than 4% of the recording time) compared with the high amount observed in the patients with obstructive sleep apneas (mean 42.9% of the recording time). The high sensitivity, easy use, and low cost of the automatic SCSB method make it suitable for the quantification of the periodic breathing during night and for the screening of sleep apneas.