Imagine a garden hose hooked up to a spigot. When the hose is flexible and there are no kinks in it, you can turn on the water full blast and it will flow easily through the hose. But if there’s a kink in the hose, the water doesn’t flow as well beyond the kink. And the pressure inside the hose builds up behind the kink. Or imagine there is gunk inside the hose blocking the path of the water. Your arteries are a lot like that garden hose.
She'll inflate the cuff to a pressure higher than your systolic blood pressure, and it will tighten around your arm. Then she'll release it. As the cuff deflates, the first sound she hears through the stethoscope is the systolic blood pressure. It sounds like a whooshing noise. The point where this noise goes away marks the diastolic blood pressure.
Blood pressure readings fall into four general categories, ranging from normal to stage 2 high blood pressure (hypertension). The level of your blood pressure determines what kind of treatment you may need. To get an accurate blood pressure measurement, your doctor should evaluate your readings based on the average of two or more blood pressure readings at three or more office visits.
Healthcare professionals use a stethoscope and a manual sphygmomanometer to measure your blood pressure. Typically they take the reading above your elbow. The sphygmomanometer has a bladder, cuff, bulb, and a gauge. When the bulb is pumped it inflates the bladder inside the cuff, which is wrapped around your arm. This inflation will stop the blood flow in your arteries. The stethoscope is used to listen for sound of the heartbeat, and no sound indicates that there is no flow. As the pressure is released from the bladder, you will hear the sound of the blood flowing again. That point becomes systolic reading. The diastolic reading is when you hear no sound again, which means that the blood flow is back to normal.