Long-term cardiopulmonary monitoring in bed without subject awareness

A system by which the cardiac and respiratory activities could be monitored in bed was developed with new sensors. The system requires no electrodes fasten on the body surface, hence no preparation for monitoring is required when going to bed. This monitoring concept is essential in a part of home health care to relieve from one´s duty to measure one´s health by oneself. The cardiac activities are observed by acquiring electrocardiograms (ECG), and the pulmonary activities are monitored by measuring electrical capacitance around the thorax. The electrodes to sense the activities were set in the bed sheet, which are composed of electrically conductive textiles. Thus the subject merely lies on the bed to be monitored wearing regular night clothes. Electrocardiograms and respiratory activities were successfully obtained during sleep with fairly free position