Anytime you have gone to the doctor you have had a sphygmomanometer used on you by the nurse or doctor. Most people do not know that a blood pressure meter is really a sphygmomanometer. They are just called blood pressure monitors because it is a less technical name for the device, not to mention easier to say. This is a common tool that is used to measure blood pressure. A man named Samuel Siegfried Karl Ritter von Basch is the person who invented the sphygmomanometer back in 1881. A much easier one to use was developed by another man named Scipione Riva-Rocci in 1896. However, the sphygmomanometer didn’t really catch on and become popular with medical doctors until about 1901.
The blood pressure monitor is a common tool used in every medical office and hospital today. It consists of an inflatable cuff that is placed around the upper arm to restrict the blood flow. Either a mercury or a mechanical manometer is then used which measures the blood pressure. Old fashioned sphygmomanometers are also used in conjunction with a stethoscope. Advances in technology have now given us digital sphygmomanometers that do not need to use mercury at all.
There are actually three types of sphygmomanometers now. The aneroid type is a mercury free blood pressure monitor. It needs a stethoscope that is attached. A valve is used to inflate the cuff and it has an easy to read gauge. The cuff must be able to fit snuggly when it is inflated around the arm. The cuffs come in different sizes to fit different sizes of arms. If the cuff is too small it will not give an accurate reading and the blood pressure will read higher. If the cuff is too large it can give an incorrect low blood pressure reading. When used the cuff is inflated to restrict the blood flow in the arm. The doctor or nurse will then listen to the brachial artery with a stethoscope. The stethoscope is usually placed on the artery in the inner part of the elbow. When the pressure is released from the cuff the doctor will be able to hear the blood pressure sounds against the artery. They note when the sound first begins and when it can no longer be heard. This gives them the systolic and diastolic reading.
A digital sphygmomanometer also uses an inflatable cuff, only it is small. A digital blood pressure meter is best used in a noisy environment or by someone who is hearing impaired because you do not have to listen to the artery with a stethoscope. A digital sphygmomanometer measures the mean arterial pressure. These blood pressure meters are not considered to be as accurate as the first kind. However, the wrist cuff digital blood pressure monitors may be considered the most accurate. The smallest sphygmomanometers on the market are the digital finger cuff models. They are easy to use and portable. However, they may not be as accurate as the wrist cuff models. The digital sphygmomanometers are battery operated and can be used with one hand, so self monitoring is easier and a good option for people with hypertension to monitor daily blood pressure. They are mercury free and much safer to use than the ones that contain mercury. With a digital blood pressure meter you can see the readings on a digital screen. No stethoscope is required and they are simple to use. Some of the more expensive models will store readings in memory which can be printed out.
The third type of sphygmomanometer is the manual type. These have mercury manometers which can give absolute measurements. This kind is often used on high risk patients and in clinical trials where accurate blood pressure readings are needed. However, the use of mercury based sphygmomanometers has declined since 2000 because of the dangers that mercury can pose in cases of breakage. The manual type is also used in conjunction with a stethoscope. The proper use of the manual type takes some practice getting used to it before correct readings can be taken.