The mystery of blood pressure monitors!

Dear Mom,

An important part of good health care is keeping an eye on our blood pressure.  What I mean is that each of us has a responsibility to take care of ourselves.  This is especially important if we have been diagnosed with high blood pressure by our primary health care provider.  Since your doctor said you have hypertension, that means that your blood pressure is above 140/90 mm Hg.(1)  The reason this should be of concern to you is that high blood pressure can lead to heart disease if it remains high.  

Please take good care of yourself  -- take your blood pressure every morning  before breakfast and then again in the evening.  Measuring blood pressure with a monitor is part science and part art.  The science is how the cuff of the blood pressure monitor can feel the change in blood flow that is happening inside your arm when the cuff is inflated and deflated.  The art is in positioning and inflating the cuff, as well as controlling the pressure as it is deflated to get an accurate reading.  If you are interested in more detailed information, click on this site from the Mayo Clinic Advice on taking your own blood pressure

In general how it works is this:  the blood pressure cuff goes on your upper arm and then air is pumped into the cuff.  As the cuff squeezes your arm, the blood temporarily stops flowing through a large artery in your arm.  When the cuff is slowly deflated, the blood begins moving through the artery again.  This is your systolic pressure--basically, the pressure your heart exerts to send your blood on its way through your body.  We continue listening until we can't hear the blood moving through the artery any longer.  This is the diastolic pressure--the measure of pressure in your artery when your heart is taking a break between beats. 

A doctor or nurse will place a stethoscope on your arm over the artery in order to hear when the blood stops and restarts.  Your home blood pressure monitor does this automatically for you. 

Here is a picture that shows how the inflation of the cuff stops the flow of the artery.  Then how the first sound heard is the systolic pressure and the last sound heard is the diastolic pressure reading.

http://www.mootah-medical.com/en/images/30-08.gif

Mom, I just wanted to let you know that one of the best things you could do each day is get a little exercise and then relax and smell the roses :)

Love you,  Mary

(1)  Lewis, S., Dirksen, S., Heitkemper, M., Bucher, L., & Harding, M. (2014). Medical-Surgical Nursing: Assessment and Management of Clinical Problems (9th ed., p. 715). St. Louis: Elsevier Mosby.