Checking Your Blood Pressure

ADC6014 ADVANTAGE6014 Advanced B P MonitorFollow your doctor’s instructions for when and how often to check your blood pressure.

Keep in mind that certain factors can cause blood pressure to temporarily rise. Blood pressure normally rises as a result of:

  • Stress
  • Smoking
  • Cold temperatures
  • Exercise
  • Caffeine
  • Certain drugs

Avoid any of these factors that you can when taking your blood pressure. Also try measuring blood pressure at about the same time each day.

HOW DO I TAKE MY BLOOD PRESSURE?

Before taking your blood pressure:

  • Find a quiet place. (You will need to listen for your heartbeat.)
  • Roll up the sleeve on your left arm or remove any tight-sleeved clothing, if needed. (It’s best to take blood pressure from the left arm, if possible.)
  • Rest in a chair next to a table for five to 10 minutes. (Your left arm should rest comfortably at heart level.)
  • Sit up straight with your back against the chair, legs uncrossed.
  • Rest your forearm on the table with the palm of your hand facing up.

TAKING YOUR BLOOD PRESSURE

If you purchase a manual or digital blood pressure monitor, follow the instruction booklet carefully. The following steps provide an overview of how to take your blood pressure using either a manual or digital blood pressure monitor.

1. Locate your pulse

Locate your pulse by lightly pressing your index and middle fingers slightly to the inside center of the bend of the elbow. Here you can feel the pulse of the brachial artery. If you cannot locate a pulse, place the head of the stethoscope (on a manual monitor) or the arm cuff (on a digital monitor) in the same general area.

2. Secure the cuff

A. Thread the cuff end through the metal loop and slide the cuff onto your arm, making sure that the stethoscope head is over the artery. (When using a manual monitor, the cuff may be marked with an arrow to show the location of the stethoscope head.) The lower edge of the cuff should be about 1 inch above the bend of your elbow. Use the Velcro wrap to make the cuff snug, but not too tight.

B. Place the stethoscope in your ears. Tilt the earpiece slightly forward to get the best sound.

3. Inflate and deflate the cuff

If you are using a manual monitor:

A. Hold the pressure gauge in your left hand and the bulb in your right.

B. Close the airflow valve on the bulb by turning the screw clockwise.

C. Inflate the cuff by squeezing the bulb with your right hand. You may hear your pulse in the stethoscope.

D. Watch the gauge. Keep inflating the cuff until the gauge reads about 30 points (mm Hg) above your expected systolic pressure. At this point, you should not hear your pulse in the stethoscope.

E. Keeping your eyes on the gauge, slowly release the pressure in the cuff by opening the airflow valve counter clockwise. The gauge should fall only two to three points with each heartbeat. (You may need to practice turning the valve slowly.)

F. Listen carefully for the first pulse beat. As soon as you hear it, note the reading on the gauge. This reading is your systolic pressure.

G. Continue to slowly deflate the cuff.

H. Listen carefully until the sound disappears. As soon as you can no longer hear your pulse beat, note the reading on the gauge. This reading is your diastolic pressure.

I. Allow the cuff to completely deflate.

IMPORTANT: If you released the pressure too quickly or could not hear your pulse DO NOT inflate the cuff right away. Wait one minute before repeating the measurement. Start by reapplying the cuff.

If you are using a digital monitor:

A. Hold the bulb in your right hand.

B. Press the power button. All display symbols should appear briefly, followed by a zero. This indicates that the monitor is ready.

C. Inflate the cuff by squeezing the bulb with your right hand. If you have a monitor with automatic cuff inflation, press the start button.

D. Watch the gauge. Keep inflating the cuff until the gauge reads about 30 points (mm Hg) above your expected systolic pressure.

E. Sit quietly and watch the monitor.

F. Pressure readings will be displayed on the screen. For some devices, values may appear on the left, then on the right. Most devices will also display your pulse rate.

G. Wait for a long beep. This means that the measurement is complete. Note the pressures on the display screen. Systolic pressure appears on the left and diastolic pressure on the right. Your pulse rate may also be displayed in between or after this reading.

H. Allow the cuff to deflate.

IMPORTANT: If you did not get an accurate reading, DO NOT inflate the cuff right away. Wait one minute before repeating the measurement. Start by reapplying the cuff.

4. Record your blood pressure.

Record the date, time, and systolic and diastolic pressures.

© 2012 WebMD, LLC. All rights reserved.

What causes very low blood pressure?

Blood pressure is measured in millimeters of mercury. The first or upper number is known as the systolic blood pressure. It is the pressure that occurs in the arteries when the heart muscle contracts and pumps blood.

A normal systolic is 120 or less. Blood pressure of 120 to 140 is considered pre-hypertensive. A systolic over 140 is considered hypertensive.

The diastolic is the second or lower number. It is the pressure in the arteries when the heart relaxes and fills with blood. A diastolic of less than 90 is considered normal.

If you are using an automatic blood pressure cuff, it may be reading the diastolic lower than it actually is. This is often a problem if the blood pressure cuff is too big or too small for your arm.

Low blood pressure is only a concern when a patient has symptoms such as being lightheaded, a change in vision, losing consciousness, shortness of breath, or poor exercise tolerance. Patients most commonly complain of these symptoms when standing up from a sitting position or sitting up after lying down for awhile. This is called orthostatic hypotension and usually lasts only a short time. Patients with these symptoms need to seek medical attention.

Hypotension (low blood pressure) is most commonly caused by medications. Blood pressure medications, antidepressants and other drugs can impair the nerves of blood vessels in the legs. Normally these nerves make blood vessels in the leg contract when one is rising. When the blood vessels do not contract when changing position, blood is pooled in the legs. This deprives some blood volume from the heart, and the symptoms occur due to decreased blood perfusion of the brain.

Some patients have symptomatic low blood pressure due to a low amount of fluid in their body. This is called hypovolemia. It can be due to dehydration, caused by sweating from exercise, decreased oral intake, or use of a diuretic. Diuretics are commonly used to treat high blood pressure, but one of the most common diuretics that people encounter is caffeine.

Uncommon reasons for a low blood pressure include problems of the heart. One way that most people’s bodies deal with a small amount of dehydration is to increase the heart rate, but some patients have a heart problem that does not allow them to increase their heart rate. This is often treated with a pacemaker.

Congestive heart failure is often associated with high blood pressure but can also be associated with symptomatic low blood pressure. New onset congestive heart failure is an emergency.

Very rarely, the cause of the symptomatic low blood pressure cannot be determined. There are some drug therapies that are used in these cases. Increased salt intake is often a simple solution.

Low blood pressure without any symptoms merits a medical evaluation, but rarely needs to be treated.

Conditions Expert 
Dr. Otis Brawley Chief Medical Officer,
American Cancer Society