Материал: General propedeutics of internal diseases_Nemtsov-LM_2016

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various pulse on both hand its characteristics is examined on that side where they are expressed better.

After definition of similarity (uniformity) of pulse on both hands, a physician determines rhythmicity of pulse. For definition of rhythmicity of pulse 2, 3, 4 fingers of a palpating arm are positioned on a radial artery, and the big finger on a forward surface of a forearm from the back side. If pulsations follow one after another through identical intervals pulse is rhythmical (pulsus regularis, s. rhythmicus). When the cardiac rhythm is upset, pulse waves follow at irregular intervals (pulsus irregularis, s. arrhythmicus). Some pulse waves may be missing or they may appear prematurely, which is characteristic of extrasystole and also complete arrhythmia (fibrillation), in which pulse waves follow one another at irregular intervals.

In normal conditions, pulse is rhythmic and the pulse wave uniform. Such a pulse is called uniform (pulsus equalis). In cardiac rhythm disorders, when the heart contracts at irregular intervals, the pulse wave becomes nonuniform, and this pulse is called unequal (pulsus inequalis).

For definition of pulse rate a physician puts three fingers of a palpating arm (2-, 3-d, 4-th) on radial arteria and counts number of pulse strokes for 15 s or 30 s and received number multiply accordingly on 4 or on 2 (at rhythmical pulse). At arrhythmic pulse rate is counted inventory within 1 minute. A normal frequency of pulse rate is 60-90 in 1 minute.

A pulse rate more than 90 for 1 minute pulse refers to frequent pulse (pulsus frequens). Decrease of a pulse rate less than 60 for 1 minute refers to infrequent pulse (pulsus rarus).

The condition of the vascular wall should be assessed simultaneously. To that end, the artery is pressed by the index and middle fingers of the left hand slightly above the point where the pulse is examined by the right hand. When the vessel stops pulsating under the fingers of the right hand, the arterial wall is felt. A normal artery is a thin elastic tube. In norm an arterial wall is mild, elastic, smooth, and flat. In some diseases, for example, in atherosclerosis, the arteries change, their walls become firm, and the course more tortuous. If calcification is considerable, the artery walls are rough, tortuous tubes, sometimes with bead-like thickenings.

For definition filling (volume) of pulse three fingers of a palpating arm (the 2-, 3-d, 4-th) are placed on a. radialis. In the beginning the 2-nd finger squeezes a. radialis up to the arrest of a reversed current of a blood from vessels of a hand, and then the 4-th finger squeezes out a blood from the vessel and squeeze it up to the arrest of transit of pulse wave. The 3-rd finger freely lies on an empty arteria. The 4-th finger is raised with pulse wave. Pulse wave passing under the 3-rd finger raises it and hits about the 2-nd finger. Filling of pulse is estimated on a degree of arising of the 3-rd finger.

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Normal pulse is of satisfactory filling. It is distinguished pulse of good filling - complete pulse (рulsus plenus), and bad filling - empty pulse (рulsus vacuus). Complete pulse may be in sportsmen during sports meets, at exercise stresses. Pulse volume shows the artery filling with blood, which in turn depends on the amount of blood that is ejected during systole into the arterial system and which produces variations in the artery volume. Pulse volume depends on the stroke volume, on the total amount of circulating blood, and its distribution in the body. If the stroke volume is normal and the artery is sufficiently filled with blood, the pulse is said to be full (pulsus plenus). In abnormal circulation and blood loss, the pulse volume decreases (pulsus vacuus).

Strain of pulse, or pulse pressure, is determined by the force that should be applied to the pulsating artery to compress it completely. For definition of strain of pulse the 2-, 3-d, and 4-th fingers of a palpating arm squeeze an artery up to the arrest in it pulsations. This property of pulse depends on the magnitude of the systolic arterial pressure. If arterial pressure is normal, the artery can be compressed by a moderate pressure. A normal pulse is therefore of moderate tension, or of satisfactory strain. The higher the pressure, the more difficult it is to compress the artery; such a pulse is called pulsus durus (hard or high-tension pulse). If the arterial pressure is small, the artery is easy to compress, and the pulse is soft (pulsus mollis).

Pulse size. The pulse size implies its filling and tension. It depends on the expansion of the artery during systole and on its collapse during diastole. These in turn depend on the pulse volume, fluctuation of the arterial pressure during both systole and diastole, and distensibility of the arterial wall.

Pulse wave increases with increasing stroke volume, great fluctuations in the arterial pressure, and also with decreasing tone of the arterial wall. This pulse is called high pulse (pulsus altus) or pulsus magnus. Large-volume or high pulse is characteristic of aortic valve incompetence in thyrotoxicosis, when the pulse wave increases due to the high difference between systolic and diastolic arterial pressure. Such a pulse may develop in fever in connection with decreased tone of the arterial wall.

Pulse wave decreases with decreasing stroke volume and amplitude of pressure fluctuations during systole and diastole and with increasing tone of the arterial wall. The pulse becomes small pulse (pulsus parvus). Pulse is small when the amount of blood discharged into the arterial system is small, and the rate of its discharge is low. This is observed in stenosis of the aortic orifice or of the left venous orifice, and also in tachycardia and acute cardiac failure. The pulse wave may be quite insignificant (barely perceptible) in shock, acute cardiac failure and massive loss of blood. This pulse is called thready pulse (pulsus filiformis).

In rare cases (in rhythmic pulse), high and low pulse waves are alternating. This is alternating pulse (pulsus alternans). It is believed that this

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pulse is due to alternation of heart contractions that vary in force. It usually occurs in severe myocardial affection.

Deficiency of pulse is a disharmony between a heart rate and a number of pulse waves on periphery. Deficiency of pulse is defined by a palpatoryauscultative method. For deficiency of pulse the heart rate does not corresponds with the pulse rate on radial artery.

There are two methods for definition of deficiency of pulse:

1. It is performed by one physician. The doctor simultaneously positions the bell of the stethoscope on the point of an apex beat for counting of heart rate, and other loose arm - on the radial artery for scoring the pulse rate during 1 minute. 2. It is performed by two physicians. In this case the first physician listens to heart and counts heart rate within 1 minute, and the second physician counts the pulse rate on the radial artery during the same time. Then among the number of cardiac beats is subtracted the pulse rate and received the deficiency of pulse.

Presence of deficiency of pulse is typical in atrial fibrillation.

Measuring arterial pressure (taking blood pressure)

The pressure of the blood in the arterial system varies rhythmically, attaining its maximum during systole and lowering during diastole. This is explained as follows; when blood is ejected during systole it meets resistance of the arterial walls and of the blood contained in the arterial system; the pressure in the arteries thus increases to cause distention of the arterial walls. During diastole the arterial pressure falls and remains at a certain level due to the elastic contraction of the arterial walls and resistance of the arterioles, owing to which the blood flow into the arterioles, capillaries, and veins continues. It follows therefore that arterial pressure is proportional to the amount of blood ejected by the heart into the aorta (i. e. the stroke volume) and the peripheral resistance.

Arterial pressure is expressed in millimeters of mercury column. The normal systolic (maximal) pressure varies from 100 to 140 mm Hg and diastolic (minimal) from 60 to 90 mm Hg, The difference between systolic and diastolic pressure is called the pulse pressure (normally it is 40-50 mm Hg). Arterial pressure can be measured by a direct or indirect method. In the direct method, the needle or a cannula is introduced directly into the artery and connected to a pressure gauge. This method is mostly used in heart surgery.

Three techniques exist to take blood pressure indirectly. These are auscultatory, palpatory, and oscillographic. The auscultatory method is commonly used in medical practice. The method was proposed by N. Korotkoff in 1905 and is used to measure systolic and diastolic blood pressure. A sphygmomanometer is used to read pressure. It consists of a mercury or a spring manometer which is connected to a cuff and rubber bulb

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used to inflate the cuff through a connecting tube. A valve on the bulb is used to admit air into the cuff and the manometer, and to hold pressure at the needed level. A more accurate instrument is a Riva-Rocci mercury manometer. This is a mercury container communicated with a thin vertical glass tube attached to a scale graduated in millimeters from 0 to 300.

The pressure in the brachial artery is usually measured. To that end the arm of the patient is freed from tight clothes and a cuff is attached snugly and evenly onto the arm (a finger-breadth between the cuff and the skin). The inlet socket of the cuff should be directed downward, 2-3 cm above the antecubital fossa. The arm should be placed comfortably on a level surface, the palm up; the muscles of the arm should be relaxed. The phonendoscope bell is placed over the brachial artery in the antecubital space, the valve on the bulb is closed, and air is pumped into the cuff and the manometer. The pressure of the air in the cuff that compresses the artery corresponds to the mercury level as read off the instrument scale. Air is pumped into the cuff until pressure inside it is 30 mm above the level at which the brachial or radial artery stops pulsating. The valve is then opened slowly to release air from the cuff. Using the phonendoscope, the brachial artery is auscultated and the readings of the manometer followed. When the pressure in the cuff drops slightly below systolic, tones synchronous with the heart beats are heard. The manometer readings at the moment when the tones are first heard are taken as the systolic pressure. This value is usually recorded to an accuracy of 5 mmHg (e.g. 135, 130, 125mmHg, etc.). When pressure inside the cuff equals diastolic pressure, and the blood flow is no longer obstructed, the pulsation of the vessel suddenly decreases. This moment is characterized by a marked weakening and disappearance of the tones.

In normal condition an arterial pressure changes in rather appreciable limens -from 100/70 - up to 140/90 mm Hg. In healthy female the inferior border of a normal arterial pressure (BP) compounds 90/60 mm Hg.

According to classification of levels the BP (WHO/ISH, 1999) the folowing categories of the normal BP:

Optimal BP - less than 120/80 mmHg, Normal BP - less than 130/85 mmHg, High normal BP - 130/85 -139/89 mm Hg.

Arterial pressure of healthy subjects varies physiologically within a certain limit depending on physical exertion or emotional strain, the posture, time of meals, and other factors. The lowest pressure is normally observed at rest, before breakfast, in the morning, i.e. in conditions under which basal metabolism occurs. This pressure is therefore called basal. When pressure is taken for the first time, it may appear slightly higher than actual which is explained by the patient's response to the procedure. It is therefore recommended that pressure be taken several times at a run without taking off the cuff but only deflating it completely. The last and the least value should

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be considered the closest to the true pressure. A transient increase in the arterial pressure may occur during heavy exercise (especially in persons who are unaccustomed to it), in excitation after taking alcohol, strong tea or coffee, in heavy smoking or during attacks of intense pain.

Many diseases are attended by changes in arterial pressure. Elevation of systolic pressure over 140 mm and of diastolic over 90 mm Hg is called arterial hypertension. A drop in the systolic pressure below 100 mm and of diastolic below 60 mm Hg is known as arterial hypotension. Longstanding elevation of arterial pressure occurs in essential hypertension, many renal diseases (glomerulonephritis, vascular nephrosclerosis), in certain endocrinological diseases, and heart diseases, etc. Systolic pressure alone is sometimes elevated, whereas diastolic pressure remains normal or decreased. This causes a marked increase in the pulse pressure. This condition occurs in aortic incompetence, thyrotoxicosis, less markedly in anemia of any etiology and atherosclerotic affections of the vessels.

Percussion of heart

Conception of cardiac (heart) dullness

Percussion is used to determine sizes, position and configuration (shape) of a heart and its vascular bundle.

The right contour of dullness of the heart and the vascular bundle is formed (from top to bottom) by the superior vena cava to the upper edge of the 3rd rib and by the right atrium at the bottom. The left contour is formed by the left part of the aortic arch at the top, then by the pulmonary trunk, by the auricle of the left atrium at the level of the 3rd rib and downward by a narrow strip of the left ventricle. The anterior surface of the heart is formed by the right ventricle. Being an airless organ, the heart gives a dull percussion sound. But since it is partly covered on its sides by the lungs, dullness is dual in its character, i.e. it is relative (deep) and absolute (superficial). The relative cardiac dullness is the projection of heart anterior surface onto the chest. It corresponds to the true borders of the heart. The relative cardiac dullness is covered by the lungs. The absolute dullness of heart corresponds to the anterior surface of the heart that is not covered by the lungs.

Rules of percussion of heart:

1. Percussion is performed in most cases in a vertical position of the patient, with the arms lowered downwards, at impossibility of keeping of this rule it is possible to confine percussion in a horizontal position. It should, however, be remembered that the area of cardiac dullness in the vertical position is smaller than in the horizontal. This is due to mobility of the heart and the displacement of the diaphragm as the patient changes his

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