Blood pressure

With each beat, your heart contracts, sending a surge of pressure into the bloodstream. This surge period is called systolic and it is the first number in a blood pressure reading. After the surge period, your heart rests briefly and expands in preparation for another beat. This expansion period is called diastolic and it provides the second number in a blood pressure reading. Thus, a blood pressure reading of "120 over 80" means you have a systolic pressure of 120 and a diastolic pressure of 80.

I agree with fpl and want to add that when I was on the rescue squad years ago, it was often difficult to obtain a blood pressure in transit to the hospital and if we could get the first number ( systolic pressure ), that was preferred over the lower ( diastolic pressure ). As cheap as some blood pressure kits are these days, I'd recommend everyone have a kit and learn to use it. Mark Savage, Retired EMT/fireman