Perfusion of isolated bodies

Perfusion of isolated bodies - the transmission liquid via the cavity or blood vessels of the body separated from the whole body and placed in an artificial environment. Perfusion provides for a certain time maintaining functioning of the bodies and their most important functional properties (for example, isolated heart warm-blooded when perfusion reduced within a few hours).
Perfusion of isolated bodies is blood or physiological solution.
Perfusion of isolated bodies in experimental conditions allows to study the peculiarities of the functioning of the authorities to investigate the mechanisms of action of pharmacological substances.
Perfusion in surgery most often used during operations on the heart and large vessels, the treatment of malignant tumors. In the latter case, it perfusion environment add anticancer drugs. Equipment for artificial circulation (AIK-RP-62,the TL-64, LIS-3) consist of two main components: an artificial light (oxygenator) and artificial heart (pump). At a full artificial circulation of venous blood from a hollow vein on the cannula is made through the ear and the wall of the right atrium of the patient enters the oxygenator, where is saturated with oxygen and is exempt from carbon dioxide.
From the pump oxygenator the blood is pumped into the arterial system of the patient (one of femoral arteries). When the subsidiary perfusion use several schemes: the outflow of blood from the leg or jugular vein, the return to the femoral artery; with veno-venous perfusion cannula is introduced into the jugular and femoral vein; with arterio-arterial perfusion use one of femoral arteries. Training apparatus: after the liberation from the blood machine washed with warm water, then all items are immersed in 10-20% solution of sodium hydroxide. Sterilization carried out by autoclaving, boiling, dry heat or chemical means (diiid). Heparinized blood to fill the machine is prepared for 12-24 hours before the operation. Citrate blood should be used only in southertelecom. At filling of apparatus blood include crane for oxygen, and sometimes and carbon dioxide. The staff take the blood sample to hemolysis and for the study of acid-base balance. Devices that do not require a filling in blood, fills in 5% glucose solution in the number of 500-750 Jr.
Cm. also Circulation (artificial), Heart (operations).

Perfusion of isolated bodies. Perfusion - transmission through the blood vessels of the body, a body part or the whole organism liquids, physiological fluids, blood or blood fluids. Perfusion in most cases used in physiology to study the functions of the different organs, organ systems and the whole organism.
Perfusion of isolated bodies is divided into two types: perfusion bodies, completely removed from the body, and perfusion of the authorities in situ, that is found in the body, but isolated from its General of the vascular bed.
Along with the opportunity to study the function of one or another authority in simplified terms, out of touch with the whole body, the method P. acting gives the opportunity to explore the physiological significance of many biologically active substances (enzymes, hormones and other). In this way were established chemical mediators that transmit the process of excitation in the nerve-muscle (motor) and mineralnych synapses [levy (O. Loewi), A. Century Kabakov]. Wide application method P. I. O. found when studying the pharmacodynamics of various medicinal substances and chemical preparations (N. P. Kravkov). P. acting opens new perspectives in surgery for the transplant of separate organs and tissues (see below - Perfusion of isolated bodies in surgery and endocrinology for the study of the synthesis and metabolism of certain hormones, and their reception in its purest form.
As a special form of perfusion of isolated authorities should allocate culture method bodies, which is to maintain vital activity of the body and the ability of its separate cells for reproduction in the next few days and weeks. This method requires the creation of special conditions (careful selection and regular shift perfusiology environment, strict asepsis and others). The big merit in the development of this method belongs to the Carrel (A. Carrel). Wide application method perfusion of isolated bodies found in the study of cardiac function (A. A. Kulyabko, S. C. Andreev and others).
Perfusion of the whole organism used for various Fiziol. research and finds wide application in operations on a dry heart (see artificial Circulation).
Depending on Fiziol. features perefuterovka authority and tasks, which are solved at the same time, a methodical approach and the selection of technical means may differ greatly from each other. The simplest scheme P. acting is the following (Fig. 1): perfusiology body removed from the body and placed in a thermostat or in solution, the temperature of which is supported on a given level, connected to the vessel with perfusiology liquid, located at a certain height in relation to the body. As a result, the liquid under certain hydrostatic pressure enters the blood vessels and, passing through the tissues of the body, comes out; on the way fluid to the body it passes the heat exchanger, where it is heated to the desired temperature; through perfusiology liquid ignored the bubbles of air or oxygen. When perfusion such well-differentiated bodies warm-blooded animals and man, as the heart, brain, kidneys, liver, etc. are required: compliance with the optimum temperature conditions, careful selection perefuterovka solution, a certain level of pressure and oxygen saturation, create buffer systems in solution, etc., In some cases, to create conditions for normal functioning of the body should be playing pulse push, as is the case in natural conditions.
This is the simplest linear circuit perfusion, where arising out of body fluid collected in the beaker to account for the speed of a liquid through the body, directly in the body is not returned. For perfusion of such a body as the brain, or to sustain bodies for many hours and days of the culture of bodies), as well as for perfusion of the whole organism linear scheme turns out to be unsuitable. In addition, perfusiology fluid should be in these cases
either blood or replacement fluids, such as blood serum, together with the solution of Tirade. For these purposes finds application ring scheme perfusion, which stemming from the body the blood by means of any device is re-directed into the body (Fig. 2)acquiring before it the necessary parameters (level pressure, level, oxygen therapy, gas composition and other). This ensures the continuity of circulation. The work of such schemes provide lung machine, which normally functions and discharge oxygenation perform different units (pump - artificial heart, oxygenator - artificial light). Such devices include: autojector C. C. Bryukhonenko, unit for regional perfusion AIK TL-64 (Fig. 3), pump Carell - Lindbergh (Fig. 4). In the apparatus S. A. Nadirashvili, A. A. winner and I. I. Kiseleva (scheme given in Fig. 2) functions and pump oxygenator combined in one unit, which considerably simplifies work with him.

Fig. 1. The simplest installation scheme for perfusion of isolated bodies: 1 - beaker for collection and accounting perfusiology fluid flowing out of the body; 2 - thermometers; 3 - a vessel for perefuterovka body; 4 - heat exchanger; 5 - a vessel with perfusiology liquid; 6-oxygen cylinder; 7 - heating device.
Fig. 2. The scheme of the device for perfusion of isolated bodies: 1 - funnel to drain perfusiology fluid; 2 and 6 - thermometer; 3 - manometer; 4 - heat insulation casing of the device; 5 - pipe for inflow perfusiology fluid to the body and for its outflow; 7 - perfusiology authority (schematically); S - heating device; 9 - fluid surrounding perfusiology body; 10 - receiver flowing from the body perfusiology fluid (blood); 11 - oxygen cylinder;12 - pump oxygenator.
Fig. 3. The apparatus artificial circulatory for regional perfusion AIK TL-64 (General view).