Heart being the most vital organ
in the human body is the best purifier that works in an amazing way of pumping
blood throughout the body and purifying it. As the heart pumps blood, a force
is exerted on the artery wall by the blood circulation, which is measured as
the blood pressure by the BP monitors or Sphygmomanometers.
The blood pressure in a normal or
a healthy individual ranges between 110/70 to 120/80. It is referred to as the
systolic to the diastolic ratio and a change in this ratio either leads to
hypertension or low blood pressure which is either way harmful.
Blood Pressure Cuff:
With the advancement in the
technology, you no longer need to take the trouble traveling to a practitioner
or wait in the long queue for just checking your blood pressure. This
travelling and waiting may intern affect your BP levels. It’s at this point the
BP cuffs or Sphygmomanometers are serving better purpose.
A traditional sphygmomanometer
comes with an inflatable cuff made out of cloth/vinyl, a bulb for inflating,
and a mercury meter to note the values of the pressure levels. The cuff is inflatable and plays a key role
in measuring the pressure exerted on artery walls by blood circulation.
How does a Blood Pressure Cuff Work?
Blood pressure cuff is basically a sensor which notices
the changes in the blood pressure. It is made with cloth or vinyl fabric and designed
in different layers so that it can be filled with air in the inner layers. When
the pumping bulb is used to inflate the cuffs, the inner cavity is filled with
air and creates an outer pressure on the arm and is held firmly in place on the
upper arm.
When the pressures in these cuffs
are changed accordingly to match the systolic and diastolic ratios, the mercury
meter or a digital manometer attached to the cuffs measure the pressure. A pumping
bulb is attached along with the apparatus in the traditional monitors and as
well as the aneroid manual manometers and doctors normally use these traditional
manometers and the stethoscope to note the systolic and diastolic measurements
by listening to the kortkoff sounds.
Blood Pressure Cuff Operation:
When the cuff is inflated, it restricts the
blood flow, creating a pressure on the upper arm. The doctors now listen for
the kortkoff sounds many times before noting down the pressure levels. The
kortkoff sound is the sound heard when the blood pressure in the artery and the
pressure in the BP cuffs are equal; doctors listen to a whooshing sound which
indicates the equal pressures.
Though there are many versions of
the blood pressure monitors available, most of the medical practitioners and
students still make use of the traditional manometers.
Types of Blood Pressure Cuffs:
There are mainly two types of
sphygmomanometer cuffs available (1) Manual and (2) digital.
Manual Cuffs:
In the manual category, the cuffs
come with two types of meters attached to it either the mercury manometer or
the aneroid or mechanical type of manometer with a dial. Doctors use
stethoscope to read the blood pressure levels in these manometers. The manual
mercury meter cuffs are probably the first of its kind and since then the unit
of BP has been mmHg or millimeter of mercury (Hg). But with the danger of
mercury being spilled out, the mercury meters have been replaced by the
mechanical dial aneroid meter cuffs.
But the mercury manometers are
still required in clinical trials of pharmaceuticals or of high blood
pressure-risk patients or for the checkup of the pregnant women due to their
accuracy.
The aneroid meter cuffs are now the
traditional manometers in common use. The dial when mounted on walls or stands
is less vulnerable than hand held manometers as they often require calibration.
But they are considered safer than the mercury manometer cuffs. The manometers
available at the lowest prices in this category are always less accurate and
are highly susceptible to the mechanical jarring.
Digital Cuffs:
The digital or automatic cuffs
often work on the same principle as that of the manual ones, but the digital
meters attached to these cuffs use oscillometric measurements to note the blood
pressure levels. These digital cuffs are again manual and automatic
accordingly. The completely automatic manometer cuffs are inflated by a battery
or electricity. The digital monitors display the blood pressure readings and
some even note the pulse rate and come with preset readings of the points when
the blood flow stops or starts, when the cuffs are inflated.
Of all the blood pressure cuffs,
the digital cuffs are easier and safer to use and anyone can use it on their
own as these cuffs come with a failsafe warning system, in case if the cuffs
are not wound properly around the arm.