Telemedical system for monitoring of blood pressure

Telemedical sys em o moni o ing o blood p essu e 213 TELEMEDICAL SYSTEM FOR MONITORING OF BLOOD PRESSURE V. Fabián, M. Fej o á Czech Technical Uni e si y in P ague, Depa men o Cybe ne ics, Technická 2, CZ 166 27 P aha 6, Czech Republic E-mail: abi[email p o ec ed], Phone: +420 224 357 306, Fax : +420 224 357 224 Summa y I is inc easingly clea ha he adi ional way o measu ing blood p essu e in he clinic o o ice equen ly p oduces numbe s ha g ossly o e es ima e a pa ien ’s ue blood p essu e le el. This e ec is o en caused by so called „whi e coa “ synd ome. Nowadays, o his eason i becomes mo e popula so called home moni o ing o blood p essu e, ha a enua es his e ec . In he pape , he e is desc ibed specially elemedicine sys em o moni o ing o blood p essu e. The sys em consis s o blood moni o equipmen which au oma ically epo s esul s o up- o-da e pa ien ’s measu emen s o he doc o ’s moni o ing and decision suppo (MDS) sys em using wi eless communica ion. The MDS sys em can make an e alua ion o he doc o who can immedia ely in e ene i necessa y. In oduc ion o such a sys em in p ac ice can b ing conside able imp o emen in he ea men o hype ension. Abs ak T adiním zpsobem mení laku k e (TK) o dinacích p ak ických léka a na klinikách jsou as o získá ány hodno y, k e é znan pe yšují pacien  sku ený TK. Ten o e ek je  šinou zpsoben z . „synd omem bílého pláš “ (SBP). No é echnologie umožují ozšíení domácího moni o o ání TK, k e é en o synd om znan po lauje. V lánku je popiso án ná h speciálního elemedicínského sys ému p o moni o o ání TK. Ten o sys ém se skládá z pís oje p o mení TK, k e ý au oma icky zasílá hodno y mení pomocí bezd á o é komunikace pímo k lékai, kde jsou y o hodno y pedbžn yhodnoceny pomocí sys ému p o podpo u ozhodo ání (SPR). Popiso aný sys ém mže elmi ze ek i ni lébu hype enze. 1. INTRODUCTION Blood is ca ied om he hea o all pa s o you body in essels called a e ies. Blood p essu e is he o ce o he blood pushing agains he walls o he a e ies. Each ime he hea bea s (abou 60-70 imes a minu e a es ), i pumps ou blood in o he a e ies wi h di e en alue o sys olic p essu e SP (highes blood p essu e when he hea bea s) and di e en alue o dias olic p essu e DP (lowes blood p essu e when he hea elaxes). Values o SP and DP change du ing he whole day wi h dependence on pe son’s physical and psychical ac i i y. In Fig. 1, i can be seen sys olic and dias olic blood p essu e o a s anda d heal hy pa ien du ing one day moni o ing. The e was a physical ac i i y om 16:00 un il 18:00. Fig. 1. Ambulan blood p essu e moni o ing. Fo blood p essu e measu emen we used ambulan blood p essu e onome e (hol e ) Sei a, which is shown in Fig. 2. Fig. 2. Ambulan blood p essu e moni o Sei a. Va ia ion o blood p essu e du ing he day is one o se e al easons why i is inc easingly clea ha he adi ional way o measu ing blood p essu e in he clinic o o ice equen ly p oduces numbe s ha g ossly o e es ima e pa ien ’s ue blood p essu e le el. This is a majo p oblem, since i is one o he mos impo an and equen measu emen s made by physicians. I has been known o mo e han 50 yea s ha he blood p essu es eco ded in he clinic a e subs an ially highe han eadings aken by he pa ien a home. This e ec is caused by so called „whi e coa synd ome” (WCS) ha is cha ac e ized Ad ances in Elec ical and Elec onic Enginee ing 214 by aise o blood p essu e due o s ess caused by p esence o he doc o o measu ing p ocedu e i sel . Recen s udies con i m ha he di e ence caused by WCS is o subs an ial magni ude; sys olic and dias olic p essu e measu ed in he p ima y ca e se ing (19/11 mmHg) [1]. Sel -measu emen o blood p essu e a home ( he me hod p e e ed by pa ien s) gi es a much smalle WCS (5/6 mmHg) [2], [3]. Table I shows classi ica ion o he blood p essu e alues acco ding o he B i ish Hype ension Socie y [4]. Di e ence be ween measu ed alues in he clinic and pa ien ’s ue blood p essu ed le el caused by whi e coa synd ome can mys i y he doc o and hen he pa ien is classi ied o one o he hype ension ca ego ies. Consequen ly, he pa ien s a e some imes ea ed hough hey do no need any ea men . Tab. 1. Classi ica ion o blood p essu e le els o he B i ish Hype ension Socie y. 2. EXPERIMENTAL RESULTS New echnologies o e means o in oduce home moni o ing o blood p essu e ha a enua es he whi e coa e ec . Howe e , he e a e some po en ial disad an ages. Fi s ly, i he pa ien s ha e blood p essu e moni o wi hou memo y o s o ing alues, hey ha e o w i e he alues hemsel es bu his can dec ease eliabili y o he da a. Some pa ien s w i e hei alues inco ec ly due o hei men al condi ion and capaci y [5]. Possible imp o emen is he moni o wi h in e nal memo y o measu ed da a. To collec he da a he pa ien s ha e o b ing hei moni o o he clinic. And each o hese ans e s nega i ely a ec s me ological quali y o ha equipmen . Mo eo e , he only way how o ensu e adequa e ca e is h ough egula isi s o he pa ien s in he clinician’s o ice. This e ec can be elimina ed wi h use o Blue oo h ansmission [6]. One o he in e nal pa s o blood p essu e de ice is a Blue oo h module ha sends he da a o a pa ien mobile phone. The mobile phone ecei es he da a ia i s Blue oo h module and hen sends sms wi h i ei he o a cen al da abase o di ec o he doc o . Double ansmission and necessi y o mobile phone wi h Blue oo h module a e conside able d awbacks o his solu ion. These disad an ages can be educed wi h a special elemedical sys em o moni o ing o blood p essu e. Such a sys em consis s o blood p essu e moni o equipmen which au oma ically epo s esul s o up- o-da e pa ien ’s measu emen s o he doc o ’s moni o ing and decision suppo (MDS) sys em using wi eless communica ion. Figu e 1 shows basic p inciple scheme o he elemedical sys em. Fig. 3. P inciple scheme o he elemedical sys em o moni o ing o blood p essu e. Blood p essu e moni o is a s anda d au oma ic elec onic onome e . Measu emen p inciple is oscilome ical wi h he cu on pa ien ’s a m [7]. In e nal pa o he onome e is a i s GSM module o sending measu ed alues o he second GSM module in doc o ’s o dina ion. The second GSM module is connec ed o he MDS. T ansmission is bidi ec ional and can be in he o m o SMS o GPRS. A simple block scheme o he onome e can be seen in Figu e 2. One o he in e nal pa s is also USB module o connec ion wi h PC. The MDS sys em can make p elimina y e alua ion o he blood p essu e o he doc o who can immedia ely in e ene i necessa y. The MDS can e alua e om he blood p essu e alues and oscilome ical pulsa ion se e al seconda y pa ame e s such as pulse p essu e, s oke olume, ca diac ou pu e c.[8]. Decisions o MDS a e o en based on some agg ega ions, e.g. blood p essu e ends ha a e well known om blood p essu e hol e s. Bu hese ends om elemedical sys em ha e mo e long- ime cha ac e and a e e y use ul o long- ime moni o ing o he hype ension. Ca ego y Sys olic BP [mmHg] Dias olic BP [mmHg] Blood p essu e Op imal < 120 < 80 No mal < 130 < 85 High no mal 130 – 139 86 – 89 Hype ension G ade 1 140 – 159 90 – 99 G ade 2 160 – 179 100 – 109 G ade 3 ≥ 180 ≥ 110 Isola ed sys olic hype ension G ade 1 140 – 159 < 90 G ade 2 ≥ 160 < 90 Telemedical sys em o moni o ing o blood p essu e 215 Fig. 4. Simple block scheme o blood p essu e moni o . 3. CONCLUSION Se e al simila solu ions o his p oblem al eady exis bu on he base o Blue oo h ansmission [6]. The e o e he necessi y o mobile phone wi h Blue oo h module is a legi ima e disad an age due o i s cos . The p ice o onome e using Blue oo h ansmission is much highe han he p ice o onome e wi h di ec ansmission ia GSM module desc ibed in his pape . This solu ion can b ing conside able sa ing in cos s up o 50 % compa ed o he p e ious one. The e o e, in oduc ion o he GSM elemedical sys em in p ac ice can b ing exp essi e imp o emen in his domain. The easons o ou inely measu ing blood p essu e in adul s a e e iden . Raised blood p essu e is a common condi ion ha does no ha e speci ic clinical mani es a ions un il a ge o gan damage de elops. I con e s a subs an ial isk o ca dio ascula disease, much o which is a leas pa ially e e sible wi h ea men . Finally, sc eening adul s o de ec hype ension ea ly and ini ia e ea men be o e he onse o a ge o gan damage is highly cos e ec i e [9]. The home moni o ing is a e y good and pe spec i e me hod how o dis inguish be ween eal hype ension and shee pa ien ’s ne ousness. Wi h his sys em one can hope o each mo e dis inc e enchmen s and highe e iciency o he ea men . REFERENCES [1] LITTLE P., BARNETT J., BARNSLEY L., MAEJORAM J., FITZGERALD-BARRON A., MANT D. Compa ison o ag eemen be ween di e en measu es o blood p essu e in p ima y ca e and day ime ambula o y blood p essu e. BMJ, 325/2002, pp. 254 [2] LITTLE P., BARNETT J., BARNSLEY L., MAEJORAM J., FITZGERALD-BARRON A., MANT D. Compa ison o accep abili y o and p e e ences o di e en me hods o measu ing blood p essu e in p ima y ca e. BMJ, 325/2002, pp. 258-259 [3] MCALISTER F., A., STRAUS S., E. E idence based ea men o hype ension -Measu emen o blood p essu e: an e idence based e iew. BMJ, 322/2001, pp. 908 - 911 [4] WILLIAMS B., POULTER N., R., MORRIS B., J., DAVIS M., MCINNES G., T., POTTER J., F., SEVER P., S., THOM MCG S. B i ish Hype ension Socie y guidelines o hype ension managemen 2004 (BHS-IV): summa y. BMJ, 328/2004, pp. 634-640 [5] NORDMANN A., FRACH B., WALKER T., MARTINA B., BATTEGAY E. Reliabili y o pa ien s measu ing blood p essu e a home: p ospec i e obse a ional s udy. BMJ, 319/1999, pp. 1172 [6] TensioMed, In e ne si e add ess: h p://www. ensiomed.com [7] NG K., G.: Blood P essu e Measu emen . Medical Elec onics, 2/1999, pp. 61-65 [8] JÍLEK J., ŠTORK M. Sys ém p o nein azi ní yše ení k e ního laku a hemodynamiky. Léka a echnika, 3/2004, ISSN 0301-5491, pp. 33-38 [9] LITTENBERG B., A p ac ice guidelines e isi ed: sc eening o hype ension. Ann In e n Med, 122/1995, pp. 937-939