Blood Pressure-201
Blood pressure is
essential to your life, to keep your blood moving through your
arteries and veins, bringing oxygen and nutrients to all parts of
your body, and carrying away metabolic wastes to your kidneys for
disposal.
High blood pressure, or hypertension,
means that you have too much of a good thing. When your blood
pressure significantly exceeds the level necessary for your blood to
do its job, it can damage your arteries and veins, and also your
body organs that they serve. For instance, a stroke may result from
the rupture of a blood vessel within the brain. Hypertension may
also damage your heart, your kidneys, and your eyes.
The American Heart
Association website has many webpages dealing with various aspects
of high blood pressure. Links to some of these pages are inserted
here at appropriate places, for readers who wish to dig deeper.
The causes of
hypertension for most people are not well understood. However, its
potential unfortunate effects are very well documented.
There are may
misconceptions and 'urban legends' about hypertension, that you
should not believe.
In scientific work,
pressure is often measured in millimeters of mercury, usually
abbreviated as mm Hg since Hg is the chemical shorthand for mercury.
This unit of measurement is the one normally used to characterize
blood pressure. It is also used in meteorology to characterize
atmospheric pressure.
A blood-pressure reading is actually two readings,
stated in the form ss/dd, where ss is a value for systolic blood
pressure and dd is a value for diastolic blood pressure. A systolic
blood-pressure reading is a value taken during a pumping stroke of
the heart; a diastolic blood-pressure reading is a value taken
during the heart's resting phase, in between pumping strokes. Most
of us have 60-80 heartbeats per minute, with the nominal average
being 72. Some researchers believe that an infant still in his or
her mother's womb gets conditioned to the sound of the mother's
heartbeat, and that is why so much of our music is set to rhythms
having about 72 beats per minute!
An ideal healthy value
for systolic blood pressure is 115-120 mm Hg; for diastolic blood
pressure, 75-80 mm Hg. By way of comparison, sea- level air pressure
is nominally about 1013 mm Hg.
A consistent systolic
reading in the range of 130-140 mm Hg, or a consistent diastolic
reading in the range of 80-90 mm Hg, is considered to comprise
prehypertension - meaning that you don't yet have
outright high blood pressure, but you're heading in that direction.
Even higher consistent readings comprise outright hypertension, and
imply that you should begin mitigating treatments. A systolic
reading consistently above 160, or a diastolic reading consistently
above 100, is considered quite serious.
Blood pressure does
fluctuate somewhat over time, during the day and over longer
periods. When you are relaxed and at peace, it usually is lower.
When you are anxious and/or stressed, it may go higher. Some people
become nervous when visiting a doctor, and their blood pressure goes
higher just for that reason; such people need to learn to check
their own blood pressure accurately at home.
Most people with
hypertension have absolutely no symptoms. Many of them are quite
unaware that they have a dangerous body condition. Almost always,
the only way to find out if you have hypertension is by taking a
direct measurement.
The usual method for accurately measuring blood pressure requires
two medical instruments, a sphygnomanometer and a stethoscope.
A
sphygnomanometer is a pressure-measuring device with an inflatable
cuff that is wrapped around your upper arm; the stethoscope is used
to listen to the sound of blood flow in the large artery in your
arm. The cuff is inflated by squeezing the sphygnomanometer's rubber
bulb until blood flow is temporarily stopped, and then the air
pressure in the cuff is slowly released. If the person taking the
measurements performs the procedure correctly, the sphygnomanometer
pressure-gauge reading at the instant that the sound of blood flow
first resumes is the systolic blood pressure, and the reading when
the last sound is heard as the cuff fully deflates is the diastolic
blood pressure.
Your blood-pressure readings may vary by a few mm Hg between your
right arm and your left arm, and also according to your posture and
your state of relaxation.
Special blood-pressure risk factors apply to pregnant and post-
menopausal women, athletes, people of African heritage, older
people, obese people, diabetics, smokers, heavy drinkers, and people
taking certain medications - in particular, decongestants and
birth-control pills.
No group of people is
totally immune to hypertension. Even children and babies may be
subject to it.
A few people have low
blood pressure or hypotension. (Note spelling difference!) Unless
dizziness or fainting spells becomes a problem for such people, low
blood pressure may not be harmful in and of itself.
If you are subject to
hypertension, see your doctor for advice. If your doctor approves,
try taking Alistrol, which is very often helpful and has no known
interactions with other medications that your doctor may prescribe
or recommend.
