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

Oppred fast blood flow. Od t, during which the blood proh op opred segment of the system; depends mainly on such facts as the contractile method of the myocardium and the state of the periphery. An additional role is played by the number of circulary cr, its viscosity. To determine the rate, some physiologist's reaction (for example, dilation of blood vessels, change of respiration) or easily detected in blood (radioactive isotopes, dyes ). Things entered into the blood flow should be non-toxic and have no effect on rapid blood flow; Their action on the human body should be short-lived. A test with magnesium sulfate. 1 ml of 50% or 2 ml of a 25% solution of magnesium sulfate is rapidly injected into the ulnar vein of the patient and the time of administration is noted using a stopwatch. With the blood flow, magnesium sulphate passes through the sap of the small circle and, falling into the great circulation, causes expansion of the 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 the appearance of the sensation of heat in the oral cavity is noted by a stopwatch. Normally, the blood flow rate determined by this method is 10-15 s. In the same way, the sensation of heat in the oral cavity is determined by the speed of blood flow using calcium chloride. Sometimes dekholin or saccharin is injected into a vein and the time of the appearance in the mouth of a bitter or sweet taste is noted. Try with ether. The state of blood circulation in the shorter part of the vascular system (from the ulnar vein to the pulmonary alveoli) reflects the test with ether. In this test, 0.3 ml of sterile ether is injected into the cubital vein and the time when the smell of ether appears in the exhaled air. Normally, the airtime is 4-8 s. Trying with lobelin. Intravenous administration of 1% solution of lobelin at the rate of 0.1 mg per 1 kg of the patient’s mass causes a short-term dry cough or transient dyspnea, the occurrence of which is noted by a stopwatch. This change in breathing 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 sample 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 injected dyes. 2 ml of a 20% solution of fluorescein is injected into a vein (for example, an elbow) and the time of appearance of greenish-yellow staining of the mucous membrane of the lips is noted. Normally, this time is 12-16 s. The speed of blood flow on the longer pathway of fluorescein - to the ulnar vein of the opposite arm - can be determined by taking blood from the vein of the other arm every 5 s and noting the time of appearance of dye 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 determining them using special counters on any part of the vascular bed. Method of oximeography. Blood flow velocity can also be determined by the method of oxyhemography, using the oxyhemograph apparatus, the sensor of which contains a photocell that detects a change in the color of the blood depending on its oxygenation.
Sensor apparatus strengthened on the earlobe of the subject, where he registers the saturation of blood with oxygen. At the same time, respiratory movements are recorded. After determining the initial level of blood oxygen saturation, the patient is suggested to hold the breath for 10-15 s. Then he takes a deep breath, and after a few seconds the oxyhemograph writer registers an increase in the content of oxyhemoglobin. By comparing the recording of respiratory movements with the blood oxygen saturation curve, one can calculate the time from the start of a deep breath to an increase in the level of oxyhemoglobin. This time will correspond to the time of blood flow in the area of ​​the lungs - ear. Determination of systolic and minute blood volume. Systolic (shock) volume is the amount of blood ejected by the heart each time it is reduced. The normal value of systolic volume ranges from 50 to 75 ml. The minute volume is the amount of blood emitted by the heart within 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 value of the minute volume by the number of heartbeats per minute. The most direct method Fika, based on determining the amount of substance entering the blood for 1 min, and the degree of increase of its concentration in the blood. Thus, the concentration of oxygen in the blood (O), passed through the vessels of the lungs, increases by an amount determined by arterio-venous difference (AB). Knowing the oxygen consumption per 1 minute, which is determined by its deficiency in exhaled air, and arteriovenous difference, the minute volume (MO) is calculated using the formula: MO = O / A-B More indirect methods for determining the minute volume are more common: dye dilution methods and radioisotope. The patient is injected intravenously with a dye (Evans blue) or substances labeled with radioactive isotopes, and then their concentration in arterial blood is measured. Knowing the amount of the introduced substance, its concentration in the blood and the time of passage through a certain segment 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 radioisotope methods for determining the mass of circulating blood. The colorful method is based on the introduction into the vein of 20 ml of 1% paint solution (Evans Blue), which stains the plasma and does not penetrate into the red blood cells. After 3 to 6 minutes, blood is taken for examination and the concentration of the paint in the plasma is determined colorimetrically. Knowing the amount of injected dye and its concentration in the plasma, the plasma volume is calculated, and then the entire circulating blood volume is calculated using the hematocrit index (a device for determining the relationship between the volumes of blood cells and blood plasma).

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

  1. General characteristics of methods for studying the state of the cardiovascular system
    In determining the state of health in the first place is the study and assessment of the cardiovascular system, as it is the main link that determines and limits the delivery of oxygen to working organs, and moreover, the cardiovascular system of modern man is extremely vulnerable. Data from a study conducted at rest cannot fully reflect
  2. 17 LIMITS OF RELATIVE AND ABSOLUTE HEART STANDNESS. TECHNOLOGY DEFINITIONS. DIAGNOSTIC VALUE. HEART DIMENSIONS. LENGTH, LEGAL HEART, VASCULAR BEAM WIDTH IN NORMAL AND PATHOLOGY. DIAGNOSTIC VALUE.
    The boundaries of the relative dullness of the heart. Right border. First find the level of standing of the diaphragm on the right to determine the general position of the heart in the chest. By the mid-clavicular line, deep percussion determines the dullness of percussion sound corresponding to the height of the dome of the diaphragm. Make a mark on the edge of the finger-meter, facing the clear sound. Count the edge. Further quiet
  3. Cribs Methods for studying the functional state of the cardiovascular system, 2009
    Electrocardiography, phonocardiography, echocardiography, rheography, mechanocardiography, apexcardiography, kinetocardiography, X-ray and
  4. 15. DISTRIBUTION OF PATIENTS WITH DISEASES OF THE CARDIOVASCULAR SYSTEM. COMPLAINTS (8 BASIC), THEIR DETAILS, MECHANISM. DIAGNOSTIC VALUE.
    One of the frequent complaints of persons suffering from heart disease is shortness of breath, i.e., a painful feeling of lack of air. The occurrence of shortness of breath is a sign of the development of circulatory failure, and by its severity can be judged on the degree of failure. Therefore, when questioning the patient, it is necessary to find out under what circumstances it appears. So, in the initial stages of the heart
  5. Research and evaluation of the state and functional capabilities of the cardiovascular system
    Objective: to assess the state of the functional capabilities of the cardiovascular system of the body and to identify the level of its tolerance to the load (acceptable without harm to health); master the skills of determining the functional capabilities of the cardiovascular system using functional tests. Content 1. Investigate the state of the cardiovascular system and its adaptability to
  6. DISEASES OF THE CARDIOVASCULAR SYSTEM, IMMUNE SYSTEM AND THE BLOOD SYSTEM
    Diseases of the cardiovascular system are not so common in cats, but their symptoms should be known and, if necessary, contact a veterinarian. The most prone to heart disease are Siamese, Abyssinian, Persian and Burmese cats. Males are sick more often than
  7. The study of the cardiovascular system.
    The parameters of the cardiovascular system are vital (vital) functions. Therefore, the doctor first needs to have specific knowledge of the age-related pulse rate (or heart rate) and blood pressure. The pulse rate varies depending on age and is: in newborns 120 -140 per minute (immediately after childbirth
  8. Monitoring the state of the cardiovascular system
    Electrocardiography Continuous ECG monitoring is performed for all patients, regardless of the type of surgical intervention or anesthesia option for: - detection of arrhythmias; - determination of myocardial ischemia; - detection of violations of the electrolyte balance of blood; - monitoring of the pacemaker function; - counting heart rate. The location of the electrodes. For ECG monitoring, you must have at least three
  9. 44. Raspros, inspecting, palpation in diseases of the blood system. STUDY OF THE SPLEEN, DIAGNOSTIC VALUE. PRINCIPLES OF EARLY DIAGNOSTICS OF BLOOD DISEASES.
    Questioning: complaints of weakness, easy fatigability, dizziness, shortness of breath during physical exertion, palpitations with anemia, leukemia, myeloid hypoplasia. Many diseases of the blood system are accompanied by fever, fever, loss of appetite and weight loss. When B12 anemia is characterized by burning of the tip of the tongue and its edges. With Fe anemia, there is a perversion of taste (the use of chalk,
  10. Determination of the reactivity of the cardiovascular system of the fetus according to cardiotocography during pregnancy and childbirth
    At present, cardiotocography (CTG) is an integral part of a comprehensive assessment of the condition of the fetus during pregnancy and at birth. Monitor monitoring of fetal cardiac activity significantly expands the possibilities of ante-and intrapartum diagnosis, allows you to effectively address the issues of rational management of pregnancy and childbirth, and thereby reduce the rates of perinatal
  11. 40. INSTRUMENTAL AND LABORATORY METHODS OF STUDYING THE UREGULATION SYSTEM. DIAGNOSTIC VALUE.
    Special, including instrumental, research methods support the data of general clinical examination of the patient and make it possible to first identify hidden forms of kidney disease, as well as assess the degree of activity of the process, anatomical features (size), which is important to know for a long-existing disease, asymmetry of size and shape kidneys that may be due
  12. VARIABILITY OF THE HEART RHYTHM: PHYSIOLOGICAL MECHANISMS, RESEARCH METHODS, CLINICAL AND PROGNOSTIC VALUE
    The study of heart rate variability (HRV) was started in 1965, when Hon and Lee researchers noted that the fetal distress was preceded by the alternation of the intervals between heartbeats before any discernible changes in the heart rate occurred. Only 12 years later, Wolf and co-authors revealed a correlation of a higher risk of death in patients who had myocardial infarction with
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