With the development of medicine, medical workers hope to have a better understanding of patients and to more accurately determine their condition. Since the discovery of the blood circulation system in humans (1628), doctors have been wondering if there are any abnormalities in the blood during illness? What are the effects of blood circulation on the sidewall? What is the relationship between these effects and the etiology? How to measure the effect of blood on blood vessel walls?
Blood pressure measurement is too important for humans to be true. Today, hypertension is very common, and according to statistics, there are at least 200 million hypertensive patients in China.
The first measurement of blood pressure in humans
Human understanding of hypertension is a microcosm of medical development, filled with courage and intelligence, but also intertwined with absurdity and interest. About 2000 years ago, China's "Huangdi Neijing" described the pulse as "strong and firm" and "swollen". These five characters are considered by some scholars to be the earliest records of hypertension in the world.
But humans truly realized the lifelong phenomenon of blood pressure from William Harvey, whose landmark work on blood circulation was a milestone in physiology. He noticed that when an artery was cut, blood gushed out like it was driven by pressure. By touching the pulse, he could feel blood pressure. Harvey did not propose any method for measuring blood pressure during his lifetime. The first measurement of animal blood pressure was more than 100 years after the introduction of the theory of blood circulation.
In 1733, Stephen Hals (1677-1761) of the Royal Society of England first measured the blood pressure of animals. He inserted a 9-foot-274 centimeter long and one-sixth inch diameter glass tube with a small metal tube at the end into a horse's carotid artery, and blood immediately poured into the glass tube, reaching a height of 8.3 foot-270 centimeters. This indicates that the blood pressure inside the horse's carotid artery can maintain a column height of 270 centimeters. The painter at that time depicted the situation as it was. Scientific exploration often begins with curiosity, an interesting experiment that opened the curtain on the history of human blood pressure measurement.
French doctor Purcelli (1797-1869) used a glass tube filled with mercury to measure blood pressure. Due to the density of mercury being 13.6 times that of water, this method greatly reduces the length of the glass tube used, at least the measurer does not need to stand on tiptoes or sit on a stool to check the recorded scale. Pucelli not only took a small step forward in blood pressure measurement methods, but also began to explore the physiological significance of blood pressure in the human body. Even so, there are very few patients and doctors who can withstand this blood type pressure measurement method, and literature records show that it was not until 1856 that doctors began using this method to measure people's blood pressure. Scholars are beginning to explore non-invasive methods. Since the pulsation of arteries can be felt on the surface of the body, can the pulsation of the pulse be directly transmitted to the mercury column without cutting open the blood vessels? Based on this imagination, there was a lot of exploration and design, and things began to take a turn in 1896.
In 1896, Italian doctor Rivalovich wanted to use an instrument to measure the pressure of blood on the blood vessel wall, but how to measure it? He understood the story of Hals in the early 18th century England measuring horse blood pressure. It is obvious that measuring blood pressure in this way is not safe and convenient, especially for the damage to the blood vessel wall, which is difficult to use in humans.
Improvement of blood pressure measurement
On the basis of Hals' experiment of measuring horse blood pressure, Lockheed stopped further analysis and research. After bold experiments, he finally changed into a sphygmomanometer that does not damage blood vessels. This sphygmomanometer consists of cuff, pressure gauge and balloon. When measuring blood pressure, wrap the cuff flat around the upper arm of the arm, pinch the pressure balloon with your hand, and then observe the height of the pressure gauge to estimate the value of blood pressure. Obviously, measuring blood pressure with this sphygmomanometer is much more scientific and safe than the previous measurement method of Hals. However, Lockheed's method also has significant drawbacks, as it can only measure the systolic blood pressure of the arteries, and the measured value is only a speculative approximation and is not accurate.
Scientific blood pressure measurement
In order to overcome these deficiencies, about 10 years later, Nikolay Kolotkov, a Russian, stopped perfecting Lockheed's sphygmomanometer. Its basic structure remained unchanged, except that when measuring blood pressure, a stethoscope was placed inside the cuff near the pulse of the medial artery of the cubital fossa. During measurement, when the first sound from the stethoscope is heard, the height reached by the mercury column is the systolic pressure; Then the mercury column descends, and when the sound of pulse beating weakens, the height at which the mercury column is located is the diastolic blood pressure. A large number of clinical applications have proved that this sphygmomanometer is scientific, safe and accurate in measuring blood pressure. Therefore, it has been continuously used so far.
Modern blood pressure measurement
Now people have stopped improving the sphygmomanometer. The method of determining blood pressure based on one or several measurements in the past was not very accurate. Due to the frequent fluctuation of blood pressure, mood, exercise, eating, and many other conditions can affect blood pressure.
In order to understand the dynamic changes of blood pressure within a day, various types of ambulatory blood pressure recorders have been developed. Among them, one type of finger type is used to measure pulse conduction time and input it into a computer to calculate systolic and diastolic blood pressure and mean blood pressure. It is not affected by body odor or physical activity, and the patient does not feel it during measurement, nor does it affect their rest. It can be measured more than 2000 times a day. The value measured by this sphygmomanometer can reflect the change of ambulatory blood pressure.
The significance of measuring blood pressure
The improvement of the sphygmomanometer is due to two things. Firstly, the K0 rotkoff sound in 1905 was meticulously depicted, making it easy for clinical doctors to measure systolic and diastolic blood pressure. Secondly, in 1907, Janeway's "Clinical Discussion on Blood Pressure" proposed the important clinical significance of monitoring blood pressure. By World War I, blood pressure measurement had become widely accepted, becoming the fourth vital sign routinely recorded by clinical doctors after pulse, respiration, and body temperature.
Many diseases require blood pressure monitoring, especially cardiovascular and cerebrovascular diseases, to control blood pressure and make corresponding measures. If your blood pressure is high, you should choose antihypertensive treatment as appropriate to avoid experiencing cardiovascular and cerebrovascular accidents. Especially at present, hypertension is a worldwide disease. If there is no sphygmomanometer, how can we talk about the prevention and treatment of hypertension?