When you hear the term blood pressure, what this is referring to is the actual exerted force of the blood as it circulates throughout the body. This force from the blood is placed on the sides of your blood vessels and is considered to be one of your vital signs.
The blood pressure itself can actually be considered to be arterial pressure and not actually blood pressure as this pressure usually declines as it passes through the various portions of your blood network such as your capillaries and veins. This measurement of the blood pressure is done through the use of a sphygmomanometer. The sphygmomanometer originally used mercury to measure the pressure, thus the term mmHg or inHg which quite simply refers to millimetres or inches of mercury. However mercury is no longer actually used due to its harmful properties as a heavy metal.
The most traditional means of actually measuring the blood pressure is known as auscultatory or oscillometric measuring. The first comes from Latin and means to listen. While this may not be the most accurate means, it is still the most common. When a nurse or a doctor is using a sphygmomanometer with a stethoscope, this is the form of measurement that they are doing.
At one point in time the palpitation measurements were performed by measuring the hearts palpitations. It was once thought that a measurement could be made without any tools other than the actual heart beat. While this of course is true and if you are trained enough you can get rough systolic measurements through this manner, it is in no way accurate.
The auscultatory method is the one in which a sphygmomanometer and a stethoscope is used. The sphygmomanometer is accompanied by a cuff that is inflatable. This cuff is known as the Riva-Rocci cuff and it is placed on the bicep in line with the heart. This is by far considered to be the most common and is the gold standard for the measurement of ones blood pressure. However, when the sound of the heart beat is not monitored in order to get the blood pressure such as in the case of the drug store meters or the electronic home meters, this is then known as the oscillometric method.
Blood Pressure Cuff
When it comes to the blood pressure monitor or sphygmomanometer as it is referred to by people of the medical profession, the unit itself can be broken down into two parts, this first part is the manometer. While electronic devices and home-use units do not use real mercury for their measurements, they also require calibration from time to time because of it. The other portion of the sphygmomanometer is known as the Riva-Rocci cuff.
The word sphygmomanometer itself is broken down in the same manner. Sphygmós which comes from Greek refers to ones pulse whereas meter comes from manometer or pressure meter. The pressure itself is measured in units of mercury in most cases. While in some places the pascal may be the performed unit of measurement, in general your blood pressure will either be in inches or millimetres of mercury. These are distinguished as either inHg or mmHg.
The sphygmomanometer itself was invented by Samuel Siegfried Karl Ritter von Basch, however it was Scipione Riva-Rocci in 1896 who developed the version which is used today. The most important advancement that he made on the sphygmomanometer was that of the blood pressure cuff. For this reason the cuff is known as the Riva-Rocci cuff.
The digital blood pressure monitors require calibration from time to time since they do not use any mercury. The type of sphygmomanometer used at a medical clinic uses real mercury and for that reason never needs any form of calibration. These medical use versions are also the gold standard with regards to blood pressure and are used in clinical trials among many other things.
Besides the finger blood pressure monitor, the only other blood pressure monitor which does not use the blood pressure cuff is that of the invasive monitor. This invasive monitor is placed directly into a blood vessel using a syringe-like cannulae. Once inside it is able to tell the actual blood pressure with the utmost accuracy.
Blood Pressure Device
When it comes to monitoring and taking your blood pressure, a blood pressure device will be used. However it is important to remember that while many different devices may go by varying names depending on the developer, they are all considered to be a sphygmomanometer. In its simplest form, the name roughly translates to a pulse pressure meter.
This device was originally developed back in the late 1800s and other than the digital ones available today, has not changed much in design. This is because the sphygmomanometer is the gold standard for the blood pressure monitoring.
The digital blood pressure device works on the oscillometric method. They handle their measurements by focusing on the MAP or mean arterial pressure. Once this pressure measurement has been made and before it shows you the results, it will then perform a series of calculations to determine what the systolic and diastolic pressures actually are. However for persons with varying conditions, the digital blood pressure device will not be accurate. These conditions can include things like preeclampsia, arrhythmia, arteriosclerosis, pulsus paradoxus as well as pulsus alternans.
These digital devices also come in many different forms to choose from. While they are all intended for home, or at least non-medical facility use, some are not portable. For example, the non portable type of electronic blood pressure device would be that of the ones you would see in a pharmacy. You then have the portable ones like the wrist monitor which rather than pulling the pressure from the upper arm at the level of the heart, it gets it from the wrist. You also have the digital finger monitor which uses two pressure pads to restrict blood flow.
All of these digital blood pressure devices are based on the mean blood pressure and they use a calculative equation in order to come up with the actual systolic and diastolic blood pressures.
Blood Pressure Machine
The sphygmomanometer is the blood pressure machine that you would see inside of any doctors office, hospital or even at the local pharmacy. This blood pressure machine gets its name from sphygmós, which is Greek meaning pulse and manometer, which simply means a pressure meter. It was originally developed by Samuel Siegfried Karl Ritter von Basch, but it was not until 1896 when Italian, Scipione Riva-Rocci would introduce the Riva-Rocca inflatable cuff that the machine would begin growing in popularity.
Today, this important machine is considered to be the gold standard for blood pressure measurements anywhere in the world. Starting with the inflatable cuff, this component comes with two tubes running out of it. The first tube runs through a one-way valve and into the inflation bulb. When the valve is closed and the inflation bulb is pumped, the pressure inside the cuff increases. The other tube runs into the actual sphygmomanometer where it applies pressure to a tube chamber filled with the heavy-metal mercury. For this reason, while in some rare places the pascal unit may be used for measurement, the general form of blood pressure measurement is in units of mercury. This can be either inches of mercury, inHg, or millimetres of mercury, mmHg.
Of course this is not the only blood pressure machine, however it is considered to be by far the most accurate. You also have the internal invasive blood pressure monitor which can be found in hospital triage units which is inserted directly into the blood vessel and also uses real mercury for its measurements. On top of these, you then have the digital class of blood pressure machines. The largest of course are the ones you would find in the pharmacies in that they take the bodys mean blood pressure and calculate the diastolic and systolic pressures. Likewise you also have a wrist version in which the cuff wraps around the wrist and the pressure is taken the same way through the mean pressure.
If you have to deal with a blood pressure issue and keeping track of your blood pressure can mean the difference of life and death, then it is a good choice for you to get yourself one of the small portable units so that you are able to check your pressure regularly. While they may not be the most accurate, it is far better to have a close measurement than none at all. It is always better that you be safe rather than sorry and the best way to do this is by making sure you have what you need in order to monitor and control your blood pressure levels, this means that you may need to get yourself a blood pressure machine.
Blood Pressure Monitor
The sphygmomanometer is the number one means of obtaining a persons blood pressure and it is considered by far to be the most accurate means of all non-invasive blood pressure monitoring. While there is an internal vessel blood pressure monitor, this is only used in an emergency room in situations where the sphygmomanometer would not be able to be used. Using an inflatable cuff, the blood pressure monitor which is called a sphygmomanometer by doctors, one can get their blood pressure measurements in units of mercury.
This cuff will inflate and restrict the flow of blood through the arm. When the pressure is taken by another human using a stethoscope, it is known as the auscultatory method. However for any other form of blood pressure monitor such as the electronic devices you can purchase for home use or can be found in a drug store, this is known as the oscillometric method. The two differ in the fact that the auscultatory method relies on the stethoscope and one listening to the heart beat whereas the latter relies on differentiations in the actual pressures.
Originally developed back in 1896, the sphygmomanometer is still the most common used means of measuring ones blood pressure. It is also considered to be by far the most accurate means and thus all blood pressure monitors that you would be able to obtain for home use, use this cuff. While for home use you may not have to use the stethoscope, the home blood pressure monitors will generally make sure of the oscillometric method of obtaining your blood pressure. However, keep in mind that this method is not as accurate as the auscultatory method and the blood pressure monitor may need to be calibrated from time to time.
The blood pressure monitor is placed on the bicep level with the heart as this is considered by far to be the most accurate place to obtain a measurement. There are two measurements involved in your blood pressure based on the cardiac cycle. The cardiac cycle starts with the ventricles already filled with blood in preparation of the cycle. As the ventricles open up, the pressure created is considered to be the peak and the name given to this pressure is the systolic pressure. At the end of the cardiac cycle as the ventricles are being filled up with blood once again, the moment right before the ventricles open is when the pressure is at its lowest and is known as diastolic.
Blood pressure itself is measured in units of mercury. While mercury as a substance may no longer actually be used in the sphygmomanometer, it is still the term used. In some places though the measurements may actually be done in kilopascals in which a single kPa is equivalent to 7.5 millimetres of mercury; or in simple form, mmHg. The units may also be in inches of mercury or inHg depending on whether the foot or the meter is the dominant form of measurement in your area.
Blood Pressure Monitor
Your blood pressure can actually tell a doctor a lot about you and your health, especially in cases in which you may not be able to tell the doctor yourself. The doctor can learn things like whether you have narrowed blood vessels or poor circulation; if you are eating the wrong foods or lacking certain nutrients in your diet. There is a variety of things that can be told about someone simply through their blood pressure and therefore the blood pressure is and has been considered to be one of the principal vital signs along with your temperature and pulse.
The finger tip blood pressure machine is by far the smallest currently available. This particular digital unit however does not use a cuff, but rather two very small inflatable pads in order to restrict the blood flow of the finger. The pressure measurements are once again done via the mean blood pressure and the digital unit calculates the systolic and diastolic blood pressures.
This mean pressure technique though may not work for everyone as some persons with various conditions will show inaccurate readings for the fact that their mean blood pressure would be different from that of a healthy person. Furthermore, the digital blood pressure machines may also require calibration from time to time to ensure their accuracy.