High Blood Pressure Symptoms

How is blood pressure measured

Your doctor or nurse will measure your blood pressure using a sphygmomanometer (pronounced ‘svig-mo-man-ometer’). This is usually a digital blood-pressure monitor, which is made up of a box with a tube leading to a cuff. The cuff is wrapped round your upper arm. At the press of a button, the cuff inflates to a certain level and then automatically deflates. While it is inflated, the cuff will feel slightly uncomfortable as no blood can get through to your lower arm. In the cuff there is a sensor which detects your pulse and changes the information into blood-pressure readings which appear on a display screen. The size of the cuff is important. If a cuff is too large, it can give an artificially low reading. Fat arms will need larger cuffs – otherwise the blood-pressure measurement will be higher than it actually is.

Before you have your blood pressure taken, you should have rested for at least five minutes. You should be sitting down when you have the measurement taken.Some doctors or nurses may use a mercury sphygmomanometer instead of the digital blood-pressure monitor described above. The doctor or nurse wraps the cuff round your arm and pumps up the cuff to a pressure above your likely systolic pressure. The doctor or nurse will then use a stethoscope to listen to the artery at the bend of your arm, and will then gradually release the pressure in the cuff. At systolic pressure, the blood will start to flow again. The doctor or nurse will hear this through the stethoscope as a thumping noise. As the pressure falls, the sound becomes muffled and then disappears when your blood pressure is at diastolic pressure and the blood is no longer obstructed.

Your doctor or nurse will probably check your blood pressure several times before confirming a diagnosis of high blood pressure. Once your blood pressure is well controlled, they will usually measure it every three to six months.

24-hour monitoring

Some doctors use ‘ 24-hour ambulatory monitoring ‘ to measure your blood pressure. This involves strapping a recording device – about the size of a large personal stereo – round your waist. The monitor is connected by a narrow tube to a cuff which is wrapped round your upper arm. The cuff inflates and deflates regularly throughout the day and night to take, and record, your blood pressure. While you are wearing the monitor you can carry on with all your regular daily activities apart from having a bath or shower, or swimming. 24-hour monitoring is used for several reasons, including measuring blood pressure in borderline cases, and closely monitoring the effect of drug treatment for high blood pressure. The readings from 24-hour monitoring tend to be quite a bit lower than the measurements taken in a clinic.

Changes in blood pressure

Everyone’s blood pressure varies during the day. It tends to be highest in the morning and lowest at night. Blood pressure may also become high if you are anxious or under stress. Some people get worried about seeing their doctor, and having their blood pressure taken can make it go up. Nearly everyone is nervous on the first visit and their blood pressure is usually higher than at later appointments. That is why your doctor will probably want to take two or three separate measurements, or suggest 24-hour monitoring, before deciding whether you really do have consistently high blood pressure