How Blood Pressure Is Measured

This information was taken mostly from a now forgotten web site. If it looks familiar to you let me know and I'll see that they get full credit. If you are as confused or concerned about blood pressure, maybe this will help you as it did me.

Blood pressure is expressed as 2 numbers. These numbers represent the pressure against the walls of your blood vessels as the blood moves through them. Systolic pressure is when pressure is highest in the arteries and occurs when the lower part of the heart contracts. Diastolic pressure is the minimum pressure in the arteries and occurs when the lower part of the heart relaxes. Normal blood pressure while you are resting should be less than 120 systolic over 80 diastolic, typically written as 120/80 or 120/80 mm Hg (read 120 over 80 millimeters of mercury).

If your resting blood pressure is less than 120/80, your blood pressure is normal.

If your resting blood pressure is between 120/80 and 140/90, you’re at risk for high blood pressure and have what is referred to as prehypertension. Lifestyle modifications are important and could be recommended by your doctor.

If your resting blood pressure is 140 and above for systolic or 90 and above for diastolic, your blood pressure is high. Lifestyle modifications and high blood pressure medicine are important and could be recommended by your doctor. 

If you have diabetes or chronic kidney disease, your doctor may recommend high blood pressure medicine if your blood pressure is above 130 for systolic or 80 for diastolic.

People with high blood pressure are often urged to change their diet, exercise regularly, quit smoking, and make an effort to lead less stressful lives. If changes to your lifestyle aren't effective enough, your doctor may prescribe a medication to help you manage your high blood pressure.

Medication is usually prescribed if a person’s blood pressure is above 140 systolic or 90 diastolic. There are several different “classes” of blood pressure medication. Some include:

Beta Blockers which reduce blood pressure by blocking a chemical that stimulates the heart muscle. This allows the heart to beat more slowly and less forcefully, which ultimately reduces the blood pressure within the blood vessels.

Diuretics which help your body get rid of unneeded water and salt through urine. Removing excess salt and fluid helps lower blood pressure and can make it easier for your heart to pump blood.

Angiotensin-Converting Enzyme Inhibitors (ACEIs) which help blood vessels relax by blocking the production of a hormore called angiotensin II that causes blood vessels to narrow.

Angiotensin II Receptor Blockers (ARBs) which allow blood vessels to widen by preventing angiotensin II from affecting the vessels.

Calcium Channel Blockers (CCBs) which help blood vessels relax by slowing the movement of calcium into the heart and blood vessels.

While medicines work well for many, not all medicines work well for everyone. If you feel that you are experiencing problems with your current medications, please speak with your doctor.

You should know that even with high blood pressure medication, making healthy lifestyle choices is recommended to help lower your blood pressure.

Blood pressure is constantly changing throughout the day. In the morning before you get out of bed, it is usually lowest. Once you are on your feet, it rises because you are now vertical and the blood has to be pumped harder to reach peripheral limbs. As you start moving, it increases further to meet demands of the body. During exercise, it is generally highest, but returns back to normal soon afterward. There are times when blood pressure increases during exercise are not normal however. 

Next week I'll cover how blood pressure is affected by exercise. If you have questionable blood pressure, abnormal responses during exercise, or just don't know what it is, talk to your doctor before starting a new exercise program.

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