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