“The information gathered by an intelligent t-shirt using e-textile technology is sent, without usingwires, to an information management system, which then shows the patient’s location and vital signs in real time,” explain Víctor Custodio, Gregorio López and José Ignacio Moreno, of UC3M’s Department of Telematic Engineering.  

The system is designed to be used in hospitals and can be divided into two parts: the fixed infrastructure, which would be pre-installed in the hospital, and the mobile units, which would move with the patients.

The mobile units include “intelligent t-shirt” and a localisation device, carried in a pocket and, which they intend to incorporate into the garment in the future.

The t-shirt is washable, includes electrodes that detect bioelectric power through which an electrocardiogram can be obtained. It has a removable device that includes thermometer and accelerometer, used to take the patient’s temperature, relative position (reclining, standing, etc.) and level of physical activity.

Finally, the indoor localisation unit is activated periodically, receives signals from the units that make up the fixed localisation infrastructure and wirelessly sends that information to the information management system.

Once the information is received there, the localisation algorithm that has been developed is able to establish the individual’s position within a two-meter margin of error, and to mark the spot on a map of the hospital.

 Medical applications
The prototype was developed as part of the project “LOBIN: Localización y Biomonitorización a través de Redes Inalámbricas en Entornos Hospitalarios” (Locating and biomonitoring by means of Wireless Networks in Hospitals), funded by the Ministry of Industry, Tourism and Commerce, (Advance R + D Plan)  and is the result of the collaboration of a national consortium made up of researchers at UC3M and other companies and R+D centers, such as Simave Sistemas, Nlaza Soluciones, Nuubo and the Centro Tecnológico de Telecomunicaciones de Galicia (Gradiant).

The wireless communications infrastructure and the communications software for the prototype were designed at UC3M.  In addition, the UC3M researchers carried out the phases in which the different technologies developed by the associates were integrated; this integration was later validated in the Cardiology Unit of La Paz Hospital in Madrid. 

During  validation, the system was tested 24 hours a day, with five patients monitored simultaneously.

“Thanks to this experience with the hospital personnel, who were very satisfied with the platform, we found several valuable possible improvements to the system,” say researchers.

With slight modifications, the prototype can also be applied in other areas like early diagnosis of cardiac anomalies in athletes, or telemedicine monitoring patients at home,  reducing time spent in  hospital.

The information management system stores all of the patient’s information for possible later studies, as the analysis of how a particular patient’s level of physical activity affects the electrocardiogram quality. The program also has a series of alarms,  default configured, which are activated when measured parameters exceed pre-established limits,  as 38º C body temperature or 100 heartbeats per minute. 

“All of these alarms can be modified by the doctors in order to adjust them to the specific needs of each patient; whenever any one of these alarms goes off, a message will appear on the screen and also be sent as an SMS alerting the doctor in charge or the proper hospital personnel who, at that moment, is closest to the patient in question”,  say the scientists.

The work done and the results obtained as part of this project have been presented in conferences and published in respected, international journals, such the 21st Annual IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC 2010) and the IEEE Transactions on Information Technology in Biomedicine where the UC3M researchers describe the system’s architecture, its development process, the tests that have been carried out, and the validation results.