Motivation

Broad public is increasingly getting aware of sleep-related breathing disorders. Roughlythree million people in Germany and over twelve million people in the USA suffer from sleep apnea, an intermittent stop of breathing during the course of sleep. However, only a small percentage of these people are aware of their disease. On the other hand, diagnosis at a sleep disorder center is generally very straining for the patient, time consuming, and a staff intensive procedure. Given the small number of diagnosis facilities available, it is not surprising that sleep apnea often remains undetected for a very long time.

To overcome the mentioned problems, a sleep apnea screening system is being developed within the scope of the Personal Health Monitoring project. Ease of use and a stressless application is emphasized during the development. Thus this monitoring system may also be used to observe therapy progress when used by the patient at home.

Method

A basic but effective method for respiration monitoring is the analysis of breath sounds.

Depending on the patient and on environmental conditions, breath sound may either be acquired via ambient sound recording or via an electronic stethoscope. Taking advantage of methods known from Artificial Intelligence, the preprocessed breath sounds are categorized in consideration of the causative physiological processes. Further research is performed to extend this physiological model to patients with other respiratory or lung diseases.

Integration

Within the framework of the Personal Health Monitoring System, the integration permits easy interaction with the other sensor subsystems. Especially in combination with the ECG, blood pressure and pulseoxymetry sensor subsystems, monitoring of breath sounds provides for a level of diagnosis very similar to the one accomplished in sleep disorder centers. Unlike diagnosis at a sleep disorder center, the Personal Health Monitoring System allows for long term measurements without significantly decreasing the patient's quality of life.