ABOUT “BLOOD PRESSURE”
What is blood pressure ...
The heart is a pump that circulates blood to different part of the body. Blood is pumped from the heart at a constant pressure into arteries. This pressure is called the arterial blood pressure, which repre- sents, in general, blood pressure. Blood pressure is indicated by several kinds of pressures such as: systolic pressure (maximal blood pressure) that occurs when the heart pumps blood (see the illustra- tion given below left); and diastolic pressure (minimal blood pressure) that occurs just when blood returns to the heart (see the illustration give below right).
(Maximum blood pressure) | (Minimum blood pressure) | |||
| Artery |
| Artery | |
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Left atrium |
| Left atrium |
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Left |
| Left | Normal state is | |
| ventricle | restored to the | ||
ventricle | The artery wall | |||
| artery wall. | |||
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Contracts | Relaxes |
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Blood pressure changes at all times..
Blood pressure differs with age, gender and other factors. Blood pressure of one person is likely to be affected by biorhythm of a day, posture, physical activities, mental activities, stress and atmospheric temperatures. It is said that blood pressure of a healthy person varies by 20 to 30 mmHg within a day. The chart given below shows the blood pressure variation in a day. This charge indicates that blood pressure differs in daily life.
● Example of blood pressure variation ina day |
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(mmHg) | 160 |
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| Max. blood pressure | ||
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140 |
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value | 120 |
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100 |
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pressure |
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80 |
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60 |
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Blood |
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40 |
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| Min. blood pressure | |||
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| 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 |
Time of day
- Eng 22 -