A blood pressure machine is a device that measures an individual's blood pressure, which is an indication of how hard the heart is working to circulate blood. Also commonly called a blood pressure monitor, the term blood pressure machine usually refers to the electronic, digital version. This type of monitor does all of the work of taking the measurement, leaving little room for human error. They have many applications such as in medical offices and for home monitoring.
Blood pressure is a measure of the force exerted by the blood on the walls of the blood vessels as it travels; it informs health professionals about how much work a person's heart has to do to pump and circulate the blood. It's considered a vital sign, meaning it is an extremely important measure of a person's overall health. Blood pressure machines are often used to take this measurement and are a common sight in health care settings. Blood pressure can be taken manually by a trained professional, but the use of a blood pressure machine is considered by many to be more reliable.
Typically a blood pressure machine consists of an inflatable cuff, a control unit that houses a digital screen for reading the results, and switches for operation. The cuff is wrapped around the patient's arm and inflated, pressing on the blood vessels to momentarily halt the flow of blood. Then it gradually begins to deflate, releasing the pressure on the blood vessels so the blood may resume flowing and put outward pressure on the vessel walls. This is called the systolic pressure and is recorded by the machine. As deflation of the cuff continues, the vessel eventually opens up fully, reducing the pressure on the walls, giving the diastolic reading which is also recorded.
Usually a digital blood pressure machine operates automatically, performing all the functions of measuring this vital sign. All the user need do is wrap the cuff around the arm and turn the machine on. The automatic operation generally removes most of the possibility of human error associated with the manual method of measuring blood pressure, such as the need to listen carefully through a stethoscope or record the changes in blood flow. For greater accuracy, some machines even take the measurement multiple times and then display an average.
There are a variety of blood pressure machine models available. Some manufacturers produce specific machines for professional settings or home use. Home monitoring is often recommended for individuals diagnosed with high blood pressure. There are also some machines that measure blood pressure at the wrist or fingertip, but these are not considered to be as accurate as those that use an arm cuff.