Diagnosis and treatment protocols for hypertension in India are based on the blood pressure
data generated from the western population. To generate blood pressure database for our nation,
we need accurate estimates of BP. The ideal method would be to use intra-arterial method of blood
pressure measurement, which is the gold standard. But this being an invasive procedure, it is nearly
impractical to use it to generate a database for a large population. Instead, what we would need is
way of estimating the systolic as well as diastolic blood pressures non-invasively which can give
the whole range of those pressures in an individual as it is well-known that blood pressure varies
considerably even within a single respiratory cycle. The current non-invasive methods of blood
pressure measurement can only give point values of systolic as well as diastolic blood pressure,
but not its whole range of variability which is a better risk predictor of target organ damage. The
present work proposes developing a pulse-plethysmography based non-invasive blood pressure
monitoring system (CMC NIBP) that can estimate the whole range of systolic and diastolic
pressures in an individual, which current non-invasive methods do not provide.
Management of vascular pathologies is crucial in anti-hypertensive therapies. Vascular
parameters of large and small arteries, such as compliance of large arteries and resistance of small
arteries are the major determinants of blood pressure in addition to cardiac performance. Besides
this general understanding, there is no categorical documentation on what happens to small artery
compliance and large artery resistance during vasoconstriction and the corresponding alterations
in vascular pressure. The arteriolar resistance is known to increase with vasoconstriction. While
the effect of vasoconstriction on aortic resistance is not studied well. Once this is understood well,
then any change in resistance of the arterial tree during a drug intervention could be attributed to
its effect on small arteries specifically and any change in compliance to its effect on large arteries.
This kind of differential action of vasoactive drugs on vessels should be studied well so that the
antihypertensive treatments can be tailored according to the vascular pathology underlying and
treat that specific component at fault. Assessing the vascular resistance and compliance
dynamically during a drug intervention is currently not a routine procedure. Once established, it
could give more information on how a drug is acting on the entire arterial tree and the treatments
can be targeted to the region at fault. Measuring arterial vascular impedance is a way towards
resolving arterial resistance and compliance