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24.METHODS OF STUDYING THE STATE OF THE CARDIOVASCULAR SYSTEM. DETERMINATION OF MINUTE HEART VOLUME. HEART INDEX. EMISSION FRACTION. MASS OF CIRCULATING BLOOD. HEMATOCRITIS. DIAGNOSTIC VALUE.

Determine the speed of blood flow. Definition t, during which the blood passes through the segment of the system; depends mainly on such fact as the contractile method of the myocardium and the state of peripheral. An additional role is played by the number of circular cr, its viscosity. To determine the blood circulation of a substance, call a physiologist to react (for example, vasodilation, change in respiration) or easily detect in the blood (radioactive isotopes, dyes ) Things introduced into the blood stream should be non-toxic and not have an effect on the speed of blood flow; their action on the human body should be short-term. Test with magnesium sulfate. 1 ml of 50% or 2 ml of a 25% solution of magnesium sulfate is quickly injected into the ulnar vein of the subject and the moment of administration is noted by the stopwatch. With a blood stream, magnesium sulfate passes through a small circle and, falling into a large circle of blood circulation, causes the expansion of capillaries. The latter is accompanied by a sensation of heat, primarily in the oral cavity and later in the whole body and limbs. The moment of sensation of heat in the oral cavity is noted by a stopwatch. Normally, the blood flow velocity determined by this method is 10-15 s. In the same way, according to the sensation of heat in the oral cavity, the blood flow rate is determined using calcium chloride. Sometimes decholine or saccharin is injected into a vein and the time of appearance of a bitter or sweet taste in the mouth is noted. A test with ether. The state of blood circulation in a shorter section of the vascular system (from the ulnar vein to the pulmonary alveoli) reflects the sample with ether. With this test, 0.3 ml of sterile ether is injected into the ulnar vein and the time of appearance of the smell of ether in the expired air is noted. Normally, the airtime is 4-8 s. Test with lobelin. Intravenous administration of a 1% lobelin solution at the rate of 0.1 mg per 1 kg of the subject's weight causes a short-term dry cough or transient dyspnea, the appearance of which is noted by the stopwatch. This change in respiration is associated with irritation of the pulmonary branches of the vagus nerve. Simultaneously with the determination of blood flow velocity by this method, it is possible to record respiratory movements using a kimograph. The normal duration of a lobelin test is 8-10 s. A test with dyes. Another group of methods for determining blood flow velocity is based on the determination of dilutions of intravenous dyes. 2 ml of a 20% solution of fluorescein are injected into a vein (for example, the ulnar) and the time of appearance of a greenish-yellow staining of the mucous membrane of the lips is noted. Normally, this time is 12-16 s. The blood flow velocity along the longer path of fluorescein - to the ulnar vein of the opposite arm - can be determined by taking blood from the veins of the other arm every 5 s and noting the time the paint appears in it. Normally, the blood flow velocity is 15-30 s. The radioisotope method for determining the blood flow velocity is based on the intravenous injection of isotopes (-4Na, 131I, 85Kg) and their determination using special counters on any part of the vascular bed. Oxyhemography method. Blood flow velocity can also be determined by oxyhemography using an oxyhemograph device, the sensor of which contains a photocell that detects a change in the color of blood depending on its oxygen saturation.
The sensor of the apparatus is strengthened on the earlobe of the subject, where it registers oxygen saturation of the blood. At the same time, respiratory movements are recorded. After determining the initial level of blood saturation with oxygen, the subject is asked to hold their breath for 10-15 seconds. Then he takes a deep breath, and after a few seconds the oxyhemograph writes an increase in oxyhemoglobin content. By comparing the recording of respiratory movements with the oxygen saturation curve of the blood, the time from the start of a deep breath to an increase in the level of oxyhemoglobin can be calculated. This time will correspond to the blood flow time in the area of ​​the lungs - ear. Determination of systolic and minute blood volume. Systolic (stroke) volume is the amount of blood ejected by the heart at each reduction. The normal value of systolic volume varies between 50 - 75 ml. Minute volume is the amount of blood ejected by the heart for a minute. In healthy people at rest, the minute volume is 3.5 - 8 L. In clinical practice, the minute volume is determined, and the stroke volume is calculated by dividing the minute volume by the number of heart contractions per minute. The most accurate direct method is Fick, based on the determination of the amount of substance entering the blood in 1 min, and the degree of increase in its concentration in the blood. So, the concentration of oxygen in the blood (O) passing through the vessels of the lungs increases by an amount determined by the arteriovenous difference (A-B). Knowing the oxygen consumption in 1 min, which is determined by its deficiency in exhaled air, and the arteriovenous difference, the minute volume (MO) is calculated by the formula: MO = O / A-B Indirect methods for determining the minute volume are more common: dilution methods of dyes and radioisotope. The patient is injected intravenously with dye (Evans blue) or substances labeled with radioactive isotopes, and then their concentration in arterial blood is measured. Knowing the amount of the injected substance, its concentration in the blood and the time it takes to pass through a certain section of the vascular bed, the minute volume is calculated using special formulas.

Determination of the mass of circulating blood. The most common are the colorful and radioisotopic methods for determining the mass of circulating blood. The colorful method is based on injecting 20 ml of a 1% solution of paint (Evans blue) into the vein, which stains the plasma and does not penetrate red blood cells. After 3 to 6 minutes, blood is taken for examination and the plasma concentration of the ink is determined colorimetrically. Knowing the amount of ink introduced and its concentration in the plasma, the plasma volume is calculated, and then the whole volume of circulating blood is calculated by the hematocrit index (a device for determining the ratio of the volumes of blood cells and blood plasma).

The radioisotope method is based on the introduction into the blood of the examined red blood cells labeled with isotopes. In a healthy person, the volume of circulating blood depends on body weight and is 2 - 5 liters (an average of 75 ml per 1 kg of body weight).
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24.METHODS OF STUDYING THE STATE OF THE CARDIOVASCULAR SYSTEM. DETERMINATION OF MINUTE HEART VOLUME. HEART INDEX. EMISSION FRACTION. MASS OF CIRCULATING BLOOD. HEMATOCRITIS. DIAGNOSTIC VALUE.

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    In determining the state of health in the first place is the study and assessment of the state of the cardiovascular system, since it is the main link that determines and limits the delivery of oxygen to the working organs, and in addition, the cardiovascular system of modern man is extremely vulnerable. A study conducted at rest may not fully reflect
  2. 17 BOUNDARIES OF RELATIVE AND ABSOLUTE HEART DULP. TECHNIQUE OF DEFINITION. DIAGNOSTIC VALUE. HEART DIMENSIONS. LENGTH, HEART RADIATOR, VASCULAR WIDTH WIDTH IN NORMAL AND PATHOLOGY. DIAGNOSTIC VALUE.
    The boundaries of the relative dullness of the heart. Right border. First, they find the level of standing of the diaphragm on the right in order to determine the general position of the heart in the chest. On the mid-clavicular line, deep percussion determines the blunting of percussion sound, corresponding to the height of the dome of the diaphragm. Make a mark on the edge of the finger-pessimeter, facing a clear sound. Count the rib. Further quiet
  3. Cheat sheets. Methods of studying the functional state of the cardiovascular system, 2009
    Electrocardiography, phonocardiography, echocardiography, rheography, mechanocardiography, apexcardiography, kinetocardiography, X-ray cardiography and
  4. 15. DISTRIBUTION OF PATIENTS WITH DISEASES OF THE CARDIOVASCULAR SYSTEM. COMPLAINTS (8 BASIC), THEIR DETAILS, MECHANISM. DIAGNOSTIC VALUE.
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  5. Research and evaluation of the state and functional capabilities of the cardiovascular system
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  6. DISEASES OF THE CARDIOVASCULAR SYSTEM, IMMUNE SYSTEM AND BLOOD SYSTEM
    Diseases of the cardiovascular system are not so common in cats, but their symptoms should be known and, if there is any need, consult a veterinarian. Cat Siamese, Abyssinian, Persian and Burmese cats are most susceptible to heart disease. Males get sick more often than
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    The parameters of the cardiovascular system relate to vital (vital) functions. Therefore, the doctor first of all needs to have specific knowledge about the age-related heart rate (or heart rate) and the amount of blood pressure. The heart rate varies with age and is: in newborns 120 -140 per minute (immediately after childbirth
  8. Cardiovascular Monitoring
    Electrocardiography Continuous ECG monitoring is carried out for all patients, regardless of the type of surgical intervention or anesthesia option for: - detection of arrhythmias; - definitions of myocardial ischemia; - detection of disturbances in the electrolyte balance of the blood; - monitoring the function of the pacemaker; - calculation of heart rate. The location of the electrodes. For ECG monitoring, you must have at least three
  9. 44. QUESTION, INSPECTION, PALPATION IN DISEASES OF THE BLOOD SYSTEM. RESEARCH OF SPLEEN, DIAGNOSTIC VALUE. PRINCIPLES OF EARLY DIAGNOSIS OF BLOOD DISEASES.
    Questioning: complaints of weakness, light fatigue, dizziness, shortness of breath during physical exertion, palpitations in case of anemia, leukemia, myeloid hypoplasia. Many diseases of the blood system are accompanied by fever, fever, loss of appetite and weight loss. With B12 anemia, a burning tip of the tongue and its edges is characteristic. With Fe anemia, a perversion of taste is observed (the use of chalk,
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    At present, cardiotocography (CTG) is an integral part of a comprehensive assessment of the condition of the fetus during pregnancy and childbirth. Monitoring of cardiac activity of the fetus significantly expands the possibilities of ante- and intrapartum diagnostics, allows you to effectively address the rational tactics of conducting pregnancy and childbirth and thereby reduce perinatal
  11. 40. INSTRUMENTAL AND LABORATORY METHODS OF RESEARCH OF THE URINARY SYSTEM. DIAGNOSTIC VALUE.
    Special, including instrumental, research methods support the general clinical examination of the patient and, first of all, reveal hidden forms of kidney diseases, as well as assess the degree of activity of the process, anatomical features (size), which is important to know with a long-term illness, asymmetry of size and shape kidneys that may be due
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    A study of heart rate variability (HRV) was started in 1965, when researchers Hon and Lee noted that fetal distress was preceded by an alternation in the intervals between heart contractions before any noticeable changes in heart rate occurred. Only 12 years later, Wolf et al. Found a correlation between a greater risk of death in patients who had myocardial infarction.
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