Measurements
HAVE YOUR BLOOD PRESSURE MEASURED REGULARLY
It is important to have your blood pressure measured regularly and know your blood pressure numbers. Both numbers are important. We measure blood pressure with two numbers. The top number is the systolic blood pressure and is the largest number. This is the pressure in your blood vessels when your heart beats and pumps blood. The bottom number is the diastolic blood pressure. This is the pressure in your blood vessels when your heart relaxes and fills with blood.
The higher your systolic or diastolic pressure is, and the longer these numbers are high, the more damage occurs to your blood vessels. Strokes and heart attacks are caused by damaged blood vessels.
Regular blood pressure monitoring is especially important if your blood pressure is between 130/85 and 139/89. This is called “high normal” blood pressure. More than half of people with “high normal” blood pressure develop hypertension within four years unless they make lifestyle changes.
MEASURE YOUR OWN BLOOD PRESSURE
You can help your doctor to diagnose hypertension by measuring your blood pressure at home. Home blood pressure monitoring at home may also be important if you have kidney disease or diabetes.
If you are measuring your blood pressure at home:
- Buy a blood pressure instrument that is recommended by the Canadian Hypertension Society. Look for this logo on the box:
- Blood pressure monitors can be purchased at most pharmacies.
- Ensure that the blood pressure cuff fits your arm. Choose a cuff size that covers 80% of your arm. Talk to the pharmacy staff to determine the right cuff size.
- Only buy an instrument that measures blood pressure in the upper arm. Wrist and finger units may not provide accurate readings.
- Always measure your blood pressure using the proper technique.
Blood pressure monitors with a memory are recommended as this allows your doctor to see all your blood pressure readings.
How do I measure my blood pressure with a home monitor?
When measuring blood pressure, follow these rules:
- follow the directions that come with the device.
- only measure and record my blood pressure if I have time to do it correctly.
- wait at least two hours after a big meal and for at least half an hour after drinking coffee or smoking.
- empty my bladder or bowels if I am uncomfortable before taking a reading.
- rest and relax for 5 minutes in a quiet comfortable place with no distractions (e.g. TV or talking) before measuring my blood pressure.
- put the cuff on a bare arm.
- not measure blood pressure when I am uncomfortable, cold, anxious, stressed or in pain.
- sit in a chair that supports my back and beside a table that can support my arm. If required, put a pillow ot towel under my arm so that the cuff rests at heart level. I will not cross my legs.
- measure blood pressure in the morning before taking medications and eating, and in the evening before going to bed, bathing or taking medications.
- take at least two readings each time and record them with the date and time.
- every year have the accuracy of my home monitor checked and check the instructions for measuring blood pressure to make sure I am still measuring my blood pressure properly.
- for most people, the target or “healthy” HOME blood pressure is less than 135 mm Hg systolic (top number) and less than 85 mm Hg diastolic (bottom number). If I have diabetes or kidney disease lower targets are required.
WHAT IS “WHITE COAT” HYPERTENSION?
Some people have high blood pressure when they visit a doctor’s office, but have normal blood pressure otherwise. This condition is called “white coat” hypertension. If your doctor thinks you have white coat hypertension, you may be asked to monitor your blood pressure at home or wear an ambulatory blood pressure monitor. An ambulatory blood pressure monitor is a small machine, about the size of a portable radio that you wear on your belt for 24 hours. This machine lets your doctor find out what your blood pressure was every 15 to 30 minutes. This information can help you and your doctor see the changes in your blood pressure during a normal day. Most people with white coat hypertension are not at higher risk of health problems, but they do require regular monitoring as they are more likely to develop true hypertension over time.
MASKED HYPERTENSION
“Masked” hypertension is the opposite of “white coat hypertension. People with this condition have normal blood pressure in a doctor’s office, but have high blood pressure when elsewhere. If your doctor thinks you have masked hypertension, you may be asked to monitor your blood pressure at home or wear an ambulatory blood pressure monitor. People with “masked” hypertension are at higher risk for heart disease and stroke and may require medications to control their blood pressure.
