Scientist develops SAMON system to diagnose apnea-hypopnea sleep syndrome

Apr 9 2010

The sleep study or test is key for diagnosing apnea-hypopnea syndrome but, given its high cost, few resources are earmarked to it. Computer scientist at the University of the Basque Country (UPV/EHU), Mr Alfredo Burgos, has presented a thesis that aims to solve this problem.

Apnea-hypopnea sleep syndrome is a condition that causes problems of respiration while sleeping. It is a serious problem because, on not gaining suitable sleep, it affects the daily life of the patient. In order to undertake a diagnosis, it is essential to study the alterations of the patient during sleep, but the techniques used to date are expensive and uncomfortable - the patient has to sleep in hospital in order to be monitored. Now, however, doctor in Information Technology, Alfredo Burgos, has developed a cheap and comfortable alternative to carry out the sleep study, based on latest-generation mobile technology. His PhD thesis is entitled Telemonitorisation in real time of Sleep Apneas-Hypopneas Syndrome (SAHS) using domiciliary pulsioximetry.

The alternative system of Dr Burgos is called SAMON (sleep apnea monitoring) and was drawn up at the Interoperating Database Group of the Information Technology Faculty on the Ibaeta campus (Donostia-San Sebastian) of the University of the Basque Country (UPV/EHU). It involves telemonitorisation of a patient suspected of suffering from SAHS and while they are sleeping at home. The results of the study of their sleep are transmitted to a mobile device and then to the doctor by email. It is a system that can be used at home with ease, without need of medical or nursing skills and it is suitable for generating a coordination network between the patient and the doctors.

Pulsioximetry and Smartphone as base technologies

For SAMON to be efficient, Dr Burgos had to decide which apparatus and systems of communication were the most appropriate in this specific case, taking into account that they had to be able to be used at any time in any place. Moreover, applications have been specially integrated for carrying out a sleep study and, based on this, for detecting the apnea-hypopnea syndrome.

Dr Burgos opted for pulsioximetry as the most suitable methodology for studying the patient's sleep. This involves measuring the concentration of oxygen in the blood and the heart rate using a small apparatus that is attached to the finger. To this end, in fact, he devised two computer text files for registering the concentration of oxygen and the heartbeat. He channelled these registers to a Smartphone, using Bluetooth technology. Then, thanks to GPRS (radio service that sends data in packets) and UMTS (telecommunications system used by third-generation mobile phones) technologies, this data is sent from the Smartphone to the doctor's computer in electronic mail format. In this way, Dr Burgos has managed to integrate pulsioximetry to a software analysis tool used by medical specialists.

Once the prototype was developed, the researcher carried out a primary pilot test in the Hospital Donostia (the general hospital in the Basque city of Donostia-San Sebastian). The PhD thesis shows that the study had good results. In fact, the system read the signals measuring the concentration of oxygen and the heartbeat correctly, the files containing these data were produced correctly, and the information automatically sent to the doctor's email address and without the patient having to do anything.

Results in real time

Although its was not put into practice in the pilot project, Dr Burgos has developed a method that enables detecting sleep apnea in real time and applied it to the SAMON system. To this end, he used the KDD process (Knowledge Discovery in Databases), which enables identifying patterns from extensive databases, and adapted it to the detection of the apnea syndrome. There being a direct relation between apnea and the concentration of oxygen in the blood, advantage was taken of this relationship as well as the capacity of the pulsioximetry to gather data thereof, in order to create a classification model.

This model gave quite reliable results, and is applicable to the programme. In the opinion of Dr Burgos, this is of great importance. The system, basing itself on the concentration of oxygen, will identify an episode of apnea when it actually occurs, this facilitating the capacity of diagnosis and treatment by the doctor.

Source: Elhuyar Fundazioa