It is a measure of the rate of contraction of the heart because a pulse wave is created when the left ventricle contracts.
The arteries expand in response to this contraction and increase in volume.
Once expanded, the arteries will contract forcing blood to circulate to the capillaries and then the veins. The arterial pulse is evaluated to determine the contour of the pulse wave and its volume, rate, and rhythm. The carotid pulse is the most accurate reflex of the central aortic pulse.
Accessible arterial pulse sites
Carotid artery pulse : The common carotid artery is palpated in the neck below the jaw and lateral to the larynx / trachea (that is, the midpoint between the earlobe and the chin) using the middle and index fingers.
Brachial artery pulse : The brachial artery is palpated on the anterior aspect of the elbow by gently pressing the artery against the underlying bone with the middle and index fingers.
The brachial artery pulse is commonly used to measure blood pressure with a stethoscope and sphygmomanometer.
Radial artery pulse: The radial pulse is palpated immediately over the wrist joint near the base of the thumb (ie, common site) or at the anatomical snuffbox (ie, alternate site) by gently pressing on the radial artery against the underlying bone with the middle and index fingers.
Femoral pulse : The femoral pulse is palpated on the ventral thigh between the symphysis pubis and the anterior superior iliac spine with the middle and index fingers.
Popliteal pulse : the popliteal pulse is palpated in the posterior knee with the middle and index fingers; this pulse is more difficult to palpate compared to other pulse sites.
Posterior tibial pulse : The posterior tibial pulse is palpated posterior and inferior to the medial malleolus by gently pressing the tibial artery against the underlying bone with the middle and index fingers.
Pulse of Dorsalis pedís : the dorsal pulse of the pedium is palpated in the sulcus between the first and second toes slightly medial on the dorsum of the foot (that is, dorsal-lateral to the tendon of the extensor longus of the big toe and distal to the dorsal prominence navicular bone) with the middle and / or index fingers.
Temporal pulse : The temporal pulse (that is, the superficial temporal artery) is palpated at the temple directly in front of the ear with the index finger.
Apical pulse : The unilateral apical pulse (that is, the apex of the heart) can be located in the fifth intercostal space immediately to the left of the sternum using a stethoscope.
Unlike other pulses, the apical pulse is measured over the heart rather than an artery and is commonly heard with a stethoscope rather than palpated.
When palpating the arterial pulse, the physician should observe:
Count pulse waves for 30 seconds and multiply by two or alternately count for 15 seconds and multiply by four. If the speed is very slow, fast or uneven, it is suggested that you count for a full minute.
Is the rhythm or time between beats consistent?
Does the volume or amplitude of the pulse wave feel normal? If this value decreases (that is, a decrease in stroke volume is demonstrated), it may be a reflection of dehydration or hypovolemia.
An increased pulse wave volume may be due to abnormal metabolic states, such as anemia, fever, and / or structural valvular heart disease.
A brief trip to the history of the arterial pulse and its use
“Abu Ali placed his hand on the patient’s pulse, and he mentioned the names of the different districts and continued until he reached the name of a coin by mentioning that, as he pronounced it, the patient’s pulse gave a strange start.”
“Then Abu Ali repeated the names of the different streets in that district and the different houses until he came to the name of a house at whose mention the patient’s pulse gave the same tone. Finally, he spoke the names of the different homes in that house until he came up with a name at the mention that that strange glow was resumed. ‘
“Then he said: This man is in love with such a girl, in such a house, in such a street, in such a neighborhood: the girl’s face is the patient’s cure.”
The above story about Abu Ali ibn Sina, known by his Latinized name Avicenna, Persian scholar and prominent physician of the Middle Ages, illustrating what was called “the racing pulse of a lover” shows how doctors used the arterial pulse to diagnose certain diseases in medieval times.
The simplicity of her evaluation had drawn the attention of ancient physicians to herself. Doctors of ancient times used the pulse examination not only for diagnosis, but also as an indicator of prognosis.
Immediately after pressing the pulse just below the joint of the hand, first, there is a perception of the beat of the bayu; second, or between bayu and kaph, is the perception of pitta; third or last, the perception of the beat of slesma or kaph is gained ».
This passage describes the examination and interpretation of the arterial pulse by ancient Indian physicians.
Sage Kanada (600 BC), an ancient Indian physician, alchemist and philosopher, in his book, “Science of Sphygmica”, describes a variety of pulses in different physiological and pathological states.
According to his theory, each pulse has three stages, an abnormality in any of which reflects diseases of the three main humors of the human body, bayu / vata (air), pitta (bile) and kaph / kapha (phlegm).
Ayurveda (knowledge of life) is an ancient medical science that originated in the Indian subcontinent and has been practiced since the time of Buddha (500 BC).
The pulse test is an integral part of Ayurvedic medicine. Eight parts of a patient’s body are described for a physical examination, the first being the arterial pulse.
A complete description of the pulse examination methodology has been described in three categories related to examiner, examinee, and examination method. A special method of counting the pulse rate was introduced in Ayurvedic medicine.
Heart rate was counted by “friend” with every 2.5 friends doing one minute. Furthermore, different pulsations were described for different age groups in Ayurveda.
The arterial pulse was studied in China about 2,500 years ago. It was first mentioned in “Classics of Internal Medicine, Nei Ching.” This manuscript is said to have been written by the Yellow Emperor, Huang Ti (698-598 BC).
The main means of diagnosis used in the Nei Ching is the physical examination of the arterial pulse. The pulse theory is based on the various stages of interaction between Yin (disease) and Yang (health).
Ancient Chinese physicians had to develop the skill and ability to judge the state of disease – its cause, duration, and prognosis – by the volume, strength, weakness, regularity, or interruption of the four main varieties of heartbeats. pulse (shallow, deep, slow and fast).
The examination was performed on both wrists, and the best time for the examination was early in the morning, when the Yin and Yang were believed to be in balance.
The physician would judge the pulse rate based on the relationship between the heartbeat pulse and respiration, with four beats to one breath being normal.
The arterial pulse of ancient China was divided into three parts: inch (the shortest in the hand), elbow (the highest in the arm), and bar (the one in the middle). Each of the pulse locations in each arm would represent the condition of two different organs in the body.
“There are channels (or vessels) in it (the heart) at each limb.”
Now if the priests of Sekhmet or any doctor put their hands (or) their fingers on the head, on the hands, or on their fingers on the back of the head, on the two hands, on the pulse, on both feet, he measures the heart, because its vessels are at the back of the head and at the pulse; because its pulsation is in each glass of each member ».
The above quote suggests that the relationship between the heartbeat and the peripheral circulation was conceptualized in ancient Egyptian medicine. The arteries were thought to contain air, but the whole concept of circulation is unknown.
It was also believed that the two vascular systems of the human body meet: the veins, which carry the products of digestion from the digestive tract to the entire body, and the arteries, which carry pneuma (air) from the lungs to other organs.
According to this system, the structure of the heart was not adequately explained. The left side of the heart was used to remove the pneuma from the lungs and pump it into the arteries in the rest of the body.
The word “artery” originated from the Greek word “αρτηρ’ια” which seems to derive from the word “αηρ” which means air. The pulse test was also described and de ﬁ ned in the Hippocratic writings.
Although Hippocrates (375 BC) was reported to describe the characteristics of the arterial pulse in various conditions such as fever and lethargy in his book on humors, Praxagoras of Kos (340 BC) was the first credited physician to examine the pulse in literature. ancient greek.
Praxagoras found that pulsation only occurs in arteries, not veins. His student, Herophilus (335-280 BC), was the first to describe pulsus caprizans, similar to the leap of a goat, an unusual type of pulse with two phases, an initial stroke followed by asteroid one.
Another renowned physician of antiquity was Erasistratus (304-250 BC), a contemporary of Herophilus, who was mentioned by Galen as very close to understanding circulation.
Erasistratus stated that the heart and the arteries do not move at the same instant, the arteries dilate while the heart contracts, and vice versa. He had recognized that the movement of the arteries follows the contraction of the myocardium.
Furthermore, Erasistratus correctly explained the dilation of the arteries as a passive expansion of the vessel, but incorrectly assumed that this was caused by the movement of the pneuma along the course of the arteries.
He and his contemporary physicians (Herophilus and Praxagoras) believed that arteries contain pneuma, while veins contain blood. However, how the pneuma reaches the heart and arteries is not explained in any of the writings of this time.
Herophilus believes that the dilation of the arteries draws pneuma from the heart and the contraction of the arteries moves it forward and this interaction generates the arterial pulse.
Furthermore, the arterial pulse was thought to be inherent in the arteries and totally different from the heart. This theory was believed until Galen, when it was discovered that arteries contain blood as well as air.
Herophilus was the first to compare the pulsation of blood vessels to musical rhythm, and this theory had an enormous impact on medical and musical literature up to the late Middle Ages and the Renaissance.
The up and down beats were the units Herophilus used to establish an abasic analogy between musical rhythm and the rhythm of the pulse. Herophilus defined “noticeable time” as the time interval in which a newborn’s artery would dilate.
This perceptible time became the basic unit by which the length of each contraction and dilation was measured, and hence the basic unit by which the pulse rate was established.
The most interesting part of Herophilus’ clinical interest in the pulse is his unique construction of a portable water clock or hourglass that he used on his medical rounds to examine the pulse of his patients.
This water clock would contain a specific amount of water for natural pulses of each age. Although Herophilus recognized the importance of determining the pulse rate, his followers were unable to continue their studies in this regard, and pulse rate is rarely mentioned until the 15th century.
Archigenes (98-117 CE) discovered the dicrotic pulse cited by Horine. Doctors of the Galenic era thought that the pulse has many variations, each variation with diagnostic or prognostic significance.
Archigenes described each arterial pulse as having four characteristics (length, depth, width, and speed) and believed that the bone was separated by careful palpation.
Galen (129-200 CE) thought that the dilation of the artery could be uneven on all sides and that a variety of pulses could be felt depending on the degree of dilation on each side.
For example, there could be a full ascending dilation with a less lateral dilation producing a high and narrow pulse. Similarly, there could be a full lateral dilation and a smaller one upwards, resulting in a low and wide pulse.
He described various types of arterial pulse such as serrated pulse, wavy pulse, and worm-like pulse. Other types of arterial pulsations at different temperatures or diseases, including hot pulses and cold pulses, pain pulses, inflammation, lethargy, seizures, jaundice and even elephantiasis, are described by him.
Unlike Erasistratus, Galen argued that dilation and contraction of both the heart and the arteries are simultaneous. At the time of ventricular systole, the arteries also contract and, at the time of diastole, they expand.
Galen described twenty-seven characteristics for a single pulse pulse based on its size, speed, and frequency. Galen’s observation of the double hammer pulse is interesting.
He described it quite differently from the pulsus caprizans that have no interruption between two phases of dilation, the two phases are of different size and the second much smaller than the first.