Blood Pressure

These cards include the key facts and ideas that you need to learn about blood pressure. It includes problems, causes and other related issues such as diet and lifestyle.

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What is Blood Pressure?

It is exactly what it says. It is the pressure that the blood is under to be pumped around the body. Blood is pumped around the body with contractions of the heart. The contractions increase the pressure because it is encouraging the blood to be moved faster to where it is needing to go. When it has gone through the body, it flows back to the heart to be pumped out again.

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How is Blood Pressure Measured?

It is measured in milligrams of Mercury (mmHg). A higher overall reading would mean that the blood is under a higher pressure in the arteries as it travels around the body.

When you measure the blood pressure, you are given two readings. These are the systolic and the diastolic.

The first and higher reading is the systolic. This is when the pressure is at its highest, when the heart contracts.

The second and lower reading is the diastolic. This is when the pressure is at its highest because the heart is relaxing and is not forcing blood to move through the arteries.

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What should Blood Pressure be?

In a healthy person, blood pressure should not be higher than 135/85.

If the blood pressure is significantly higher or lower, you would have a greater risk of developing health problems such as heart disease or having a stroke or kidney damage.

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What Factors can Increase Blood Pressure?

Blood pressure is controlled by your heart so ultimately, if you have a problem with your heart, there may be a reason for high blood pressure.

There are other factors from your lifestyle that can increase blood pressure:

  • Smoking
  • Being overweight
  • Drinking too much alcohol
  • Being under a lot of stress
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Smoking can increase blood pressure because the cigarette smoke contains many different chemicals which are not good for your body:

  • Carbon dioxde combines with haemoglobin in the red blood cells which reduces the amount of oxygen that the body can transport. The heart rate needs to increase to make up for the oxygen debt that the cells have because not enough oxygen was passed around the first time. The body is basically trying to catch up with itself.
  • Nicotine increase heart rate, which means the heart contracts more frequently.
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Diet can affect someones blood pressure. Saturated fats cause a build up of cholestrol. It builds up to form a plaque on the artery wall. This results in less space for the blood to flow so there is more pressure against the artery walls. This could lead to a heart attack. Cholestrol is a fatty substance and is used for other things such as making cell membranes. So, it is needed but not in any large quantities.

High salt levels can increase blood pressure and it would damage the arteries. These can work together to block the arterties which would restrict blood flow and cut off the oxygen supply to the cells. This would lead to them dying and create a heart attack.

A large amount of salt in the diet can lead to strain on the blood vessels. These become scarred and become less elastic and thicker. A cycle like this would last a few years before it was noticeable. This can lead to a heart attack because the vessels are too small.

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Heart Attacks and Heart Disease

Any disease that affects the heart is known as heart disease. This includes heart attacks. The heart muscle is supplied with blood from the coronary arteries. These can become narrowed or blocked because of lifestyle choices. These are the same as the high blood pressure risk factors. Blood flow is restricted and therefore the heart needs to pump faster to get the oxygen around the body. The heart muscle will recieve less oxygen.

A thromobosis, which is a blood clot, restricts the blood flow. A blood clot can happen to anyone but people with higher blood pressure and those with a specific blood disorder are more at risk of developing them. If a thromobosis happens, the whole blood flow would be blocked. This would mean that cells around it would die because they cannot respire because there is no oxygen. This causes a heart attack. This can cause major damage because the heart is slowly dying.

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