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8. Some Useful Information about Blood Pressure
What is Blood Pressure?
Blood pressure is a measure of the force of blood flowing
against the walls of the arteries. Arterial blood pressure is
constantly changing during the course of the heart's cycle.
The highest pressure in the cycle is called the
Systolic Blood
Pressure
; the lowest is the
Diastolic Blood Pressure
.
Both pressure readings, the
Systolic
and
Diastolic
, are
necessary to enable a doctor to evaluate the status of a
patient's blood pressure.
Why is it a Good Thing to measure Blood
Pressure at Home?
Having your blood pressure measured by a doctor can cause
anxiety which is itself a cause of high blood pressure. As a
variety of conditions affect blood pressure, a single
measurement may not be sufficient for an accurate diagnosis.
Many factors such as physical activity, anxiety, or the time of
day, can influence your blood pressure. Thus it is best to try
and measure your blood pressure at the same time each day,
to get an accurate indication of any changes in blood
pressure. Blood pressure is typically low in the morning and
increases from afternoon to evening. It is lower in the summer
and higher in the winter.
Blood pressure is measured in millimetres of mercury (mmHg)
and measurements are written with the systolic pressure
before the diastolic e.g. A blood pressure written as 140/90, is
referred to as 140 over 90 mmHg.
HEM-7080-C1_B_M.fm Page 44 Tuesday, March 9, 2010 9:05 AM
