Physical and chemical principles of functioning of an artificial kidney. Methods for cleaning colloidal systems: dialysis, electrodialysis, ultrafiltration

An artificial kidney is an apparatus for removing toxic metabolic products from the patient's blood that accumulate in severe kidney damage (acute and chronic). The operation of the device is based on the principle - the removal of low molecular weight substances from colloidal solutions due to diffusion and the difference in osmotic pressure on both sides of a semipermeable cellophane membrane. Ions of potassium, sodium, molecules of urea, creatinine, ammonia, etc. freely penetrate through the pores of cellophane. At the same time, larger protein molecules, blood cells and bacteria cannot overcome the cellophane barrier. There are two main types of artificial devices: devices with a cellophane tube with a diameter of 25-35 mm and devices with a lamellar cellophane membrane. Domestic artificial kidney refers to dialyzers with lamellar cellophane membrane. Its scheme is shown in the figure. Blood from the patient enters through the catheter using a pump into the dialyzer, which is mounted on a tank containing 110 liters of dialysis solution. Passing between the cellophane plates of the dialyzer, the patient's blood through the cellophane membrane comes into contact with the dialysis solution flowing towards. After the dialyzer, the blood enters the performance meter and then returns through the filter and air trap along the catheter to the patient's venous system. The flowing dialysis fluid is standard and contains all the main blood ions (K·, Na·, etc.), glucose in a concentration corresponding to the concentration of those in the blood of a healthy person. The solution is automatically heated to a temperature of 38°C and saturated with carbogen to pH=7.4. The clearance (purification factor) of the apparatus for urea is 140 ml/min.

A plate of organic glass is placed on the metal base of the dialyzer in a horizontal position. Two cellophane sheets are laid on it, which are covered with the next plate on top. Thus, 12 plates are laid, which are fastened with metal bolts. Cellophane membranes are perforated through special holes, as a result of which the inter-cellophane spaces are interconnected. The manometer checks the tightness of the apparatus assembly. Next, a dialyzer pump is assembled, to which a blood supply catheter is attached, and on the other side a tube attached to the dialyzer inlet. The dialyzer outlet is connected to the performance meter, to the upper end of which the blood return hose to the patient is attached. After that, the device is sterilized with diacid, washed with sterile saline and filled with blood or polyglucin. The device is connected to the patient either by arteriovenous or veno-venous method. In the first case, after exposure of the radial artery, blood is taken into the apparatus with a vascular catheter inserted into its lumen. The return flow of blood from the device goes through a catheter inserted into a superficial vein. In the second method, by exposing a large vein on the thigh, probing of the inferior vena cava is achieved, from the lumen of which blood is taken. The blood returns to the cubital vein. To quickly connect the device and conduct multiple dialysis, a shunt (vessel prosthesis) is placed between the catheterized radial artery and a nearby vein. After connecting the device, heparin is injected into the blood stream to reduce and prevent thrombosis. Hemodialysis is carried out within 4-12 hours, depending on the disease and the patient's condition.

An artificial kidney cannot completely replace kidney function, especially for a long time. However, for many months it is possible to maintain the viability of the organism at a sufficient level. An artificial kidney in some cases is a preliminary stage of a kidney operation.

artificial kidney. The operation of the artificial kidney apparatus is based on the principle of dialysis due to diffusion and the difference in osmotic pressures on both sides of a cellophane plate, which has the properties of a semipermeable membrane. Small molecules of Mg··, K·, Na·, Ca·, Cl·, HCO 3 ions and such simple organic compounds as urea, creatinine, phenol derivatives freely penetrate through the pores of cellophane. At the same time, protein molecules, blood cells on the one hand, and possible bacteria on the other cannot overcome the cellophane barrier.

Among the many models of artificial kidney devices, two main types can be distinguished: devices with a cellophane membrane shaped like a tube with a diameter of 25-35 mm, and devices with a lamellar cellophane membrane. The Kolff-Wochinger two-coil artificial kidney is most widely used abroad (Fig. 1). An important advantage of this artificial kidney model is that the spools with wound plastic hoses come from the factory in a sterile condition and can be used immediately if necessary. Ease of installation and handling, large dialysis surface (19,000 cm1) have made this model very popular. The disadvantages of the apparatus are a large capacity for blood and a significant resistance to blood flow due to the tight winding of the two dialysis hoses.

Fig.1. Scheme of the Kolff-Watchinger kidney connected to the patient: 1 - blood filter; 2 - blood pump; 3 - dialyzer; 4 - dialysis solution; a - artery, v - vein.

Therefore, a pump is installed at the inlet to the dialyzer.

The Soviet model of an artificial kidney, designed at the Research Institute of Surgical Equipment and Instruments (NIIKhAI), belongs to the type of dialyzers with a lamellar cellophane membrane.

Extensive clinical experience of Soviet and foreign clinicians shows the high efficiency of hemodialysis in the treatment of patients with renal insufficiency.

However, an artificial kidney does not replace other therapeutic measures. It is one of the most important parts of complex therapy. An artificial kidney cannot completely replace the multifaceted function of diseased kidneys, moreover, for a long time.

In the USSR, an artificial kidney began to be used since 1958 in the urological clinic of the 2nd MMI on the basis of the 1st City Hospital. Currently, more than 50 departments of clinical hospitals are equipped with an artificial kidney.

The connection of the device with the patient is usually carried out by two methods: arterial-venous or veno-venous. In the first case, after exposure of the artery (often radial), blood sampling into the apparatus is carried out with a vascular catheter inserted into its lumen. The reverse flow of blood from the device to the patient occurs through a probe inserted into any superficial vein (usually the cubital). With the veno-venous method of connection by puncture or exposure of a large vein on the thigh, probing and blood sampling from the inferior vena cava is achieved. The reverse flow of blood occurs through any vein of the forearm.

Currently, the puncture method of vascular catheterization has become widespread. The femoral artery and vein are punctured under the pupart ligament and appropriate catheters are inserted into the vessels along the conductor, which are connected to the apparatus with the help of switching lines. If during the treatment of the patient multiple use of hemodialysis is supposed, then a permanent arteriovenous shunt according to Scribner (VN Scribner) is installed on the forearm. The essence of the method lies in probing the radial artery and a nearby vein on the forearm. These probes are connected by special devices, and blood flows from the artery directly into the vein. For hemodialysis, changing the connector allows you to connect the patient's circulatory system with the artificial kidney apparatus in a few minutes. After hemodialysis, the shunt is restored again using a semicircular connector.

Artificial hemophilia is carried out by periodic administration of heparin (2 mg/kg). After hemodialysis, the effect of heparin in the patient's blood is neutralized by the introduction of a solution of protamine sulfate. All parts of the apparatus that come into contact with the patient's blood must be siliconized and sterilized.

The scheme of the Soviet model of an artificial kidney is shown in fig. 2. The patient's blood flows through the catheter (1) using the pump (2) to the dialyzer (3). Passing between the cellophane plates of the latter (in each of its 11 sections), the patient's blood through the cellophane plate comes into contact with the dialysis solution flowing towards. Its composition is usually standard and contains all the main blood ions (K·, Na·, Ca··, Mg·, Cl·, HCO 3) and glucose in concentrations necessary to correct the electrolyte composition of the patient's blood. After the dialyzer, the blood enters the performance meter (4), where blood clots and air are trapped. The blood is then returned to the patient's veins through the catheter. The dialysis solution is brought to t° 38° using an automatic heater (8) and saturated with carbogen so that its pH is 7.4. The pump (9) pumps the dialysate into the dialyzer. The blood flow rate in the dialyzer is usually 250-300 ml/min. The clearance of the apparatus is 140 ml/min for urea.

Rice. 2. Scheme of the Soviet model of the apparatus "artificial kidney": 1 - catheter; 2 - blood pump; 3 - dialyzer; 4 - performance meter; 5 - air trap; 6 - filter; 7 - catheter for returning blood to the patient; 8 - heater; 9 - pump for dialysis fluid; 10 - tank for dialysis solution; 11 - rotameter for oxygen; 12 - carbon dioxide rotameter; 13 - hydraulic drive of the perfusion pump.

At present, a new model of an artificial kidney has been constructed (Fig. 3). The basic principle of its work remains the same. The apparatus has two independent sections with a dialysis surface area of 8000 cm 2 each, with two independent pumps; it is equipped with a special device for regional heparinization and is more convenient for the treatment of patients with chronic renal failure due to the possibility of reducing the dialysis surface area.

Rice. 3. General view of the new model of the Soviet apparatus "artificial kidney" designed by NIIKHAI.

The most effective and convenient for clinical use are those artificial kidney models that meet the following basic requirements: high intensity of blood dialysis, ease and safety of handling the apparatus, and a small amount of blood. These are the devices of NIIKHAI (USSR), Kolff-Watchinger (USA) and Dogliotti (Italy). They are especially good in the treatment of patients with acute renal failure. With the most convenient devices, the modernized Kolff model and the two-plate artificial kidney of the Carina system are considered to be the most convenient. Kaden (W. Kaden, GDR) proposed an original model of an artificial kidney device for the treatment of chronic renal failure. Its main advantage is portability and low cost.

The use of chronic hemodialysis in modern conditions is an important task. According to the data of the III International Congress of Nephrologists, in some countries (USA), up to 50,000 patients with chronic renal failure of various etiologies annually need chronic hemodialysis per 100 million people. Applying an artificial kidney to a patient with chronic renal failure twice a week, it is possible to maintain the level of azotemia, normal water and electrolyte balance and a satisfactory general condition of the patient at subnormal levels. Thus, the life of patients in the terminal stage of chronic renal failure can be extended for many months and even years. An artificial kidney is beginning to be used at home, though so far in rare cases. Multiple repeated hemodialysis in patients with chronic renal failure is associated with a number of significant difficulties and various complications. These primarily include thrombosis of arteriovenous shunts. The use of Teflon-silastic material made it possible to extend the service life of the shunt up to 6-9 months. Some patients often suffer from severe peripheral nephropathy. Calcium metabolism is disturbed, which is manifested by metastatic calcification and osteoporosis. Anemia requires constant blood transfusions. Frequent complications are intermittent infection and hypertension. Testicular atrophy (in men) and amenorrhea (in women) are quite common. Finally, during repeated hemodialysis, hypercalcemia, severe anemia, septicemia, and pyrogenic reactions may develop.

It is more expedient to use chronic hemodialysis in patients in truly terminal stages of chronic renal failure, given the possible homo- and heterotransplantation of the kidney during treatment.

In patients with acute renal failure, hemodialysis allows achieving a significant clinical effect in a few hours due to the release of the body from nitrogenous toxins, normalization of water and electrolyte balance, elimination of acidosis. This sometimes may be a temporary effect allows the body to enhance the regenerative processes in the kidneys and liver, contributing to the restoration of their function. Therefore, in most etiological forms of acute renal failure, the use of an artificial kidney is indicated. These include conditions in which kidney function is often deeply impaired: collapse of the peripheral circulation due to severe operations, trauma, bleeding, post-abortion infection, incompatible blood transfusion, poisoning with nephrotoxic poisons, acute anuric glomerulonephritis, urinary tract occlusion. In chronic renal failure in the acute stage, repeated hemodialysis can significantly improve kidney function.

Important in determining indications for hemodialysis is taking into account the state of the nervous system, respiratory organs, cardiovascular system and the functional state of the liver.

The use of an artificial kidney in patients in a state of uremic coma should be considered as a late event, and, of course, the success of treatment is not always positive.

Among biochemical disorders, the leading indication for hemodialysis is
hyperazotemia, when the residual nitrogen in the blood serum is 150-200 mg% (urea content 350-400 mg%), creatinine content 12-15 mg%. An increase in the content of potassium in the blood serum up to 7 meq/l and above, a decrease in the alkaline reserve to 10 meq/l, in combination with other water and electrolyte disorders, are indications for urgent hemodialysis.

Among patients with acute renal failure, 35-45% of the disease is not too severe. Despite the presence of anuria, azotemia and other disorders, the treatment of these patients can be carried out without the use of hemodialysis.

Among the contraindications, one should take into account decompensation of the cardiovascular system, liver failure, an active septic process in the body in the phase of intermittent bacteremic shock. A fresh focus of bleeding is not considered an absolute contraindication to hemodialysis. The use of regional (only in the artificial kidney apparatus) heparinization with the help of special equipment makes it possible to avoid increased bleeding.

The use of an artificial kidney according to strict indications with the implementation of all precautions and careful monitoring of the patient during and after dialysis is practically safe and does not threaten with any complications.

The invention of the "artificial kidney" apparatus saved the lives of hundreds of thousands of people who were diagnosed with acute or chronic kidney failure. The device for hemodialysis removes toxic compounds, uric acid salts from the bloodstream, normalizes water-salt metabolism, prevents the occurrence of arterial hypertension. Without changing the volume of blood, the "artificial kidney" cleanses the human body of toxic substances in case of alcohol intoxication and drug overdose.

What is an "artificial kidney"

Acute renal failure, extensive intoxication, pulmonary edema lead to a decrease in the functional activity of the kidneys - they cannot cope with blood filtration and excretion of metabolic products from the body. The concentration of toxic substances is rapidly increasing, provoking the death of brain cells due to insufficient supply of molecular oxygen.

To save a person from inevitable death, a hemodialysis procedure is performed - the blood is purified through a special membrane that mimics the basement membrane of the kidneys.

With the help of an “artificial kidney”, the following are removed from the blood:

The products of protein metabolism are urea and its compounds.
Creatinine, the end product of chemical reactions in muscle tissue.
Toxic compounds of mercury, chlorine, arsenic, biological toxins of higher fungi and plants.
Pharmacological and narcotic drugs: barbiturates, opioids, phenobarbital, neuroleptics, tranquilizers.
Methyl and (or) ethyl alcohol.
Excess fluid.

Depending on the stage and degree of development of the disease, the patient undergoes the procedure several times a week. Such blood purification takes about 5-6 hours, while the concentration of urea is reduced by more than 70%.

"Artificial kidney" is arranged in this way:

Synthetic or cellulose membrane.
Blood purification system.
System for the preparation of dialysate.

Increasingly, cellophane membranes are used during the procedure. They allow not to filter out low-molecular useful substances - microelements and minerals. And pathogenic bacteria and toxic compounds are brought out.

Hemodialysis is used in the treatment of acute alcohol intoxication

Carrying out hemodialysis

Purification of blood with the help of an "artificial kidney" requires the preparation of the patient for the procedure. Their blood vessels are not always in good condition and many hours of extraction and injection of fluid can ruin them completely.

The problem can be solved in the following ways:

A fistula forms from an artery and vein, usually on the forearm. Vascular walls thicken and thicken after surgery, so even frequent hemodialysis is not able to break their integrity.
Under local anesthesia, a catheter is sewn into a vein located in the inguinal zone. The advantage of this method is the ability to use the device immediately after the operation.

A patient with an implantable catheter or a formed fistula is contraindicated in physical activity, weight lifting.

Before the hemodialysis procedure, the medical staff measures the patient's pulse rate and blood pressure. The most modern devices for blood purification are equipped with devices for preliminary taking these readings. Also, a person should weigh himself to assess the possible swelling of the tissues and calculate the volume of fluid that should be removed from the body.

Toxic substances and slags are removed from the bloodstream by creating excess hydrostatic pressure on the liquid separated from the solvent by a membrane. In this case, there is no diffusion of the solvent, since the pressure equalizes the content of dissolved substances on both sides of the semi-permeable membrane.

The "artificial kidney" is equipped with a special compact pump, through which blood enters the dialyzer with a membrane. After a few hours, the patient's blood is completely cleared, and the injection site is treated with disinfectant solutions, followed by the application of a sterile dressing.

A fistula is created to purify the blood using the "artificial kidney" method.

Principles of operation of the "artificial kidney"

All substances passing through the semi-permeable membrane during dialysis form dialysate. Osmotic pressure is created by the oncoming flow of the purified blood and dialysis solution. The composition of the latter is selected according to individual indicators of the patient's state of health, sometimes this function is performed by the device itself.

The principle of operation of the device is as follows:

Acute and chronic renal failure increases the concentration of toxic nitrogenous compounds and products of protein metabolism in the blood. Osmotic pressure promotes their penetration through the pores of the membrane into a less saturated dialysis solution.
The composition of the dialysis solution includes magnesium, sodium, potassium cations and chloride anions. Their concentration corresponds to that which should be in a healthy person. The passage of fluids through the membrane allows you to replenish the amount of electrolytes in the patient's blood. Used for ventilation of the kidneys.
With a decrease in the functional activity of the kidneys, the acidity of biological fluids increases. Dialysis fluid contains sodium bicarbonate, which binds to blood cells. The pH of the blood shifts to the alkaline side and normalizes.
Violation of the filtration processes in the structural elements of the kidneys provoke swelling of the tissues. When blood passes through a semi-permeable membrane, excess fluid is removed from it and accumulates in the dialysis solution. This process allows you to stabilize the condition of patients with cerebral edema.
Thrombophlebitis and venous insufficiency are dangerous due to possible blockage of the lumen of the vessels by a large thrombus. Hemodialysis with the use of anticoagulants prevents the aggregation of conglomerates.

To prevent blockage of blood vessels by air bubbles (embolism), the device "artificial kidney" is equipped with a device that destroys them or prevents their formation. After hemodialysis, measurements of the content of urea and its compounds in biological fluids are carried out.

Carrying out hemodialysis on an outpatient basis

The main types of devices "artificial kidney"

Patients with kidney disease tend to lead a normal life, go to work, spend time with family. Manufacturers of "artificial kidneys" have provided the ability to purify the blood at home. A person can independently carry out the procedure at a convenient time for him and the required number of times. Unfortunately, such a device is expensive and the patient needs to take special training courses before buying.

Hemodialysis is also performed:

At the outpatient clinic. The procedure is carried out in order of priority under the supervision of medical personnel. Patients are transported by ambulance.
In a hospital or intensive care unit. Blood purification is carried out in severe patients with acute renal failure. Also, patients with poisoning by toxic substances, alcohol intoxication, drug overdose come here.

With the development of the chemical industry and the expansion of the production of pharmacological preparations, the number of intoxications increases. Developers of devices for blood purification are constantly improving the "artificial kidney" devices, supplementing them with convenient devices. You can trace the evolution of medical equipment:

Conventional hemodialysis. Relatively small flow of blood, dialysate. The area of the cellulose membrane is about 1 sq. meters.
High Efficiency Hemodialysis. The duration of the procedure does not take more than four hours. The total surface area of the semi-permeable membrane is 2 square meters. meters, the speed of movement of liquids reaches 250 ml / min.
High flow hemodialysis. The membranes have been improved: very large conglomerates can pass through them. The procedure allows you to save useful substances and trace elements in the blood, prevents the occurrence of complications.

The devices for hemodialysis differ in the design of the filter for purifying the blood:

Disc dialyzers. Parallel plates with a semi-permeable membrane allow constant control over the quality of the filtration. Reduced risk of thrombosis, low volume of purified blood.
Capillary dialyzers. During the blood purification procedure, the risk of complications is minimized due to the rapid flow of fluids.

The choice of the device is made by medical personnel on the basis of the patient's condition and the capabilities of the medical institution.

The use of an "artificial kidney" in a hospital

Portable "artificial kidney"

Ten years ago, American scientists developed a portable "artificial kidney". The portable device weighs no more than 3.8 kg and is powered by conventional batteries. For blood purification, a fistula is also formed or an integrated intravenous catheter is installed.

The portable device "artificial kidney" does not require much time to install - within a few minutes, the doctor connects the medical equipment. If necessary, the device can operate around the clock. This is not only due to design improvements, but also due to the relatively slow fluid flow.

Implantable "artificial kidney"

The implanted "artificial kidney" will soon become a daily reality. A few years ago, the development of American scientists was presented to the public. The hemodialysis device is designed for patients with chronic renal failure. The development is especially relevant when there is a shortage of donor organs or when they are rejected by the body's own cells.

At this stage, the implantable "artificial kidney" is being tested in the laboratory. The essence of the technique is to perform the filtration function of the kidneys with a compact device. The device is equipped with biological filters with cells of the renal tubules, and the energy necessary for operation is produced by the flow of blood.

Donor kidney transplant

A kidney transplant is a surgical procedure in which an organ is transplanted from another person. Renal replacement therapy is used to treat patients with chronic renal failure of various etiologies. Usually the need for a donor kidney arises at the last stage of the course:

diabetic nephropathy.
Chronic pyelonephritis.
Polycystic kidney disease.
Chronic glomerulonephritis.

The operation significantly prolongs the life of the patient, improves its quality. Kidney transplantation is vital for young children with congenital kidney pathologies, as constant hemodialysis leads to a delay in the development of the child.

Contraindications for hemodialysis

The method of blood purification using an "artificial kidney" is contraindicated in the following cases:

Severe arterial hypertension.
Acute viral and bacterial infections.
Open form of tuberculosis.
Heart attack and stroke.
Violation of blood clotting.

These contraindications are not taken into account when the patient's life is threatened, and a connection to the "kidney" is made. After all, hemodialysis was created to prolong the life of the patient, so all risks are taken into account and attempts are made to eliminate them.

In patients suffering, with the progression of the disease, a deficiency in their functions develops. If the filtration of blood by the kidneys is reduced to 10–15%, then such patients undergo hemodialysis, that is, forced purification and removal of harmful substances from the body. This function is performed by an artificial kidney device, the use of which is indicated for patients with renal insufficiency.

If the kidneys do not cope with their function, then the patient has fatigue, vascular hypertension, edema, and dyspeptic disorders. The dialysis device helps to maintain the fluid ratio in the body and thereby normalize the acid-base balance.

What is an "artificial kidney"

The artificial kidney device is designed to purify the blood from toxic elements that accumulate in the blood due to insufficient excretory function of the organ.

The use of the device helps to normalize the electrolyte and acid-base balance, remove toxins from the body in case of poisoning, as well as excess water in case of swelling.

The provided algorithm of the device operation is based on the biological processes occurring in the body. During the procedure, the volume of circulating blood remains normal, that is, it does not increase or decrease.

How the machine works

The device for hemodialysis is a device weighing up to 80 kg, which works like a pump. Blood from the patient passes through the dialyzer, where the purification process is carried out. This equipment is made up of a large number of tubes through which blood moves. Outside, they are bathed in dialysate. The system works according to the following principle: through the membrane from which the tubes are made, toxins and excess trace elements penetrate into the liquid, while large molecules of protein, bacteria, and blood constituents remain. The process is in accordance with the laws of diffusion and the difference in osmotic pressure.

In acute renal failure, the use of hemodialysis daily is indicated until the functions of the organ are restored or the symptoms of poisoning of the body are removed. If the form of the course of the disease is chronic, then the procedure is carried out 2-3 times a week.

The manipulation is carried out by a nephrologist in a hospital or in specialized hemodialysis centers.

Types of devices

There are two main types of devices. The first type is a cellophane membrane in the form of tubes, and the second - from plates. The plate form requires less heparin for the procedure, as well as a small amount of blood, which reduces the risk of complications in the patient. The tubular shape of the membrane makes it possible to purify the blood faster and better, since it has a large area. The device consists of three blocks.

pumps supplying heparin and pumping blood;
instruments showing pressure;
air bubble prevention device.

systems for air elimination, temperature control;
mixing devices, filtration monitoring;
dialyzer blood leak sensor.

Module 3 is a filter and a hemodialysis membrane.

The design of the device allows you to automatically control the patient's pressure, his hemoglobin level, as well as adjust the composition of the dialysis solution. Modern devices independently prepare a dialysis solution according to the patient's performance. These characteristics apply only to devices used in a hospital, the best of which are the devices of the concerns BAXTER-1550, NIPRO SURDIAL, Dialog Advanced.

There are devices that can be used on an outpatient basis. This is a portable artificial kidney machine designed for home use. Its technical capabilities are lower than those of stationary devices, but it performs the main function (blood purification). Such devices are worn on the belt and weigh up to 7 kg, they are performed at any time of the day when the patient needs it. The duration of the manipulation is 3-4 hours.

The use of the device is characterized by the following features:

safety (the risk of infection is excluded);
ease of use;
manipulation at any time of the day.

These are the positive aspects of the device. The negatives include the following:

high price of the device;
control of health workers during the first sessions;
the need for training.

Despite some drawbacks in the operation of the apparatus, its use brings patients a certain freedom of movement, since blood purification can be carried out at any time without waiting in line at the hospital. A portable artificial kidney allows patients to perform simple physical work, and also performs dialysis at night.

Who should not use the device

The procedure has its contraindications. It can not be done to patients with such pathologies:

mental illness;
oncological pathologies;
leukemia or anemia;
pathology of the central nervous system;
advanced age (over 80 years);
diabetes mellitus (age after 70 years);
having more than two serious diseases.

It is impossible to carry out the procedure for patients suffering from alcoholism or drug addiction, having an active form of tuberculosis, predisposed to the development of massive bleeding.

Unwanted Effects

After or during the procedure, patients may develop undesirable effects:

The appearance of complications becomes a reaction of the body to the behavior of manipulation. If the patient does not adhere to a diet, these side effects become more. Patients with renal insufficiency are prescribed, strictly prohibiting alcohol, spicy, spicy and smoked dishes, limiting the intake of salt and liquid. If the rules of nutrition are violated, the patient creates an additional burden on the kidneys, since an increased amount of salt retains moisture in the body, leads to the formation of edema, increases the load on the heart muscle, and contributes to arterial hypertension.

During dialysis, calcium ions are washed out of the body, which contributes to destructive disorders in bone tissue. Deficiency of erythropoietin (it is produced by healthy kidneys) leads to a change in the composition of the blood. Pericarditis occurs due to the increased workload on the heart, since during the procedure it needs to pump a large volume of blood.

Conclusion

Renal failure requiring constant conduct is a very serious disease. There are no exact statistics to determine how long a patient who is on forced blood purification will live. But nevertheless, carrying out the procedure, along with compliance, as well as the normalization of the motor regimen, will prolong the patient's life. But how much - depends on the individual characteristics of the organism and concomitant diseases.

In a healthy person, the kidneys work normally, filtering toxins and liquids, even in large volumes. In some cases, the body can not cope with its work and the concentration of toxins becomes extremely high. This condition is called kidney failure.

This problem consists in the complete or partial loss of the ability of the internal organs to process and urinate. If this problem is not treated, then a person can die from intoxication, so special procedures are carried out. In the following paragraphs of the article, the topic of hemodialysis will be covered in more detail - what is it and why do it.

Principle of operation

The concept of program hemodialysis means a special procedure, which consists in removing toxins from the blood.

For this, the efferent method and a special apparatus are used, which are called "artificial kidney".

With hemodialysis, it is possible:

remove toxins that are formed during metabolism;
restore the balance of water and electrolytes.

The procedure is mainly carried out in stationary conditions and consists in the use of an apparatus with a set of special membranes that have selective permeability. The body is cleansed by removing toxins from the blood and substances with a high molecular weight that can pass through the membrane.

Depending on its type and the type of dialysis solution, the blood can be purified from certain toxins and even some proteins. In addition, some solutions can be used to make up for the lack of minerals in the human body.

"Artificial kidney" consists of several elements:

perfusion device;
dialyzer;
apparatus for mixing and supplying dialysis solution;
monitor.

The device works with the help of a special perfusion device that helps the blood flow to the dialyzer. According to its principle of operation, it is similar to a pump. After cleansing, the device sends the blood back to the human body.

The dialyzer is the heart of the device. It is in it that a special membrane is located, which allows carrying out blood filtration.

It is a reservoir divided into two parts by a special membrane. Blood is supplied to it, and on the other hand - dialysis solution. Interacting through a membrane with a certain degree of permeability, the blood is cleansed and reintroduced into the body.

The apparatus for mixing and supplying the solution is necessary so that the blood is purified and pure dialysate is supplied to the membrane, and the dialysate with waste enters a separate reservoir.

The monitor on the device is designed to track the speed of blood flow. Normally, this indicator should be about 300-450 ml/min. If the blood flow is slow, then the duration of the procedure increases, and if it is higher, then the blood does not have time to completely clear itself.

In order to normalize the rate of blood flow or, if necessary, frequent dialysis in the human body, a special fistula(see photo).

It facilitates the connection of the device and connects the vein and artery. Its installation requires a special operation. Within six months, the fistula matures and reaches the necessary stage for dialysis.

In general, the whole procedure takes about 5-6 hours. During the session, the patient can engage in any calm activities.

The procedure must be carried out by specially trained personnel.

Types of hemodialysis

Hemodialysis is divided into several types, depending on whether the procedure is performed in a hospital or at home, as well as from the functionality of the device.

Also distinguished:

hemodialysis;
peritoneal dialysis.

In the first case, an artificial membrane is used to filter the blood, and in the second, the peritoneum is used.

By venue procedures emit hemodialysis:

at home;
outpatient;
with inpatient treatment.

Hemodialysis at home involves the purchase of a special apparatus by a person.

The outpatient procedure is carried out in the hospital on a first-come, first-served basis. three times per week, but the equipment for them is more specialized. The duration of the procedure is 4 hours.

At the same time, the person is under the control of the attending physician, who can change the settings for the rate of circulation of fluids, control the volume of blood and dialysate, as well as monitor pressure and hemoglobin levels in the blood. However, many patients do not like the need to wait and visit the clinic regularly.

Hemodialysis in inpatient treatment involves the patient being in the hospital. There are not many differences from the outpatient procedure. The advantages also include the constant supervision of a doctor, and the disadvantages are the need to be in the hospital in the inpatient department. In addition, with insufficient attention of doctors, a person can become infected with hepatitis B.

The functionality of the devices for hemodialysis are also different, so there are three types of procedures:

ordinary;
highly efficient;
high-precision.

Each method has its own characteristics depending on the type of membrane in the device. Conventional hemodialysis consists in using a device with a membrane up to 12.5 sq.m. This material allows filtering small molecules at low speed (200-300 ml/min). The whole procedure takes about 5 o'clock.

Highly effective hemodialysis is carried out using a membrane with an area of 2.2 sq.m. At the same time, the rate of blood passage increases to 350-500 ml/min. At the same time, the dialysis current is also approximately twice as high. Thus the blood is cleansed faster by 1-2 hours, and it itself is better filtered and becomes cleaner than with conventional dialysis.

High-precision hemodialysis is applied using a high sensitivity membrane. It allows you to pass not only small, but also large molecules, thereby allowing you to purify the blood from a greater number of toxic substances.

A feature of this type of procedure is the possibility of penetration through the membrane of a larger amount of substances from dialysis, so it is necessary to monitor its quality.

At what creatinine is it prescribed?

The main problem in which hemodialysis is prescribed is renal failure, since the procedure is necessary for such a patient and makes it possible to prolong his life. However, it is not always prescribed, but only at a certain concentration of creatinine in the blood. With indicators over 800-1000 mcol/l hemodialysis is already prescribed.

Also included in the indications are:

alcohol intoxication;
violations of the electrolyte composition of the blood;
drug overdose;
poisoning with some poisons;
hyperhydration.

With all its advantages, the procedure also has contraindications. Some of them are absolute, that is, apply hemodialysis strictly prohibited. It:

cirrhosis of the liver;
damage to the vessels of the brain;
leukemia;
anemia;
CNS lesions;
age from 80 years (70 in the presence of diabetes);
malignant tumors;
lung diseases;
chronic form of hepatitis;
pathology of peripheral vessels in the stage of decompensation;
epilepsy;
schizophrenia;
psychoses;
alcoholism;
coronary heart disease against the background of myocardial infarction already suffered;
heart failure;
addiction.

In other cases, the decision to conduct a blood purification procedure can only be taken by the attending physician:

diseases with a high risk of developing massive bleeding after the introduction of an anticoagulant;
active forms of tuberculosis.

How many years live on hemodialysis - statistics

Considering that most often regular hemodialysis is prescribed mainly for kidney failure or kidney problems, the overall life expectancy of a person has already been reduced.

If you do not replace the affected organ with a donor one, but use the “artificial kidney” directly, then life expectancy can be even about 20 years, depending on the characteristics of human health and its general condition. The maximum is 40 years.

A person who requires regular hemodialysis against the background of a weakened heart muscle is predicted to live for about 4 years.

The average life expectancy is about 6-12 years old. In this case, the patient does not die from kidney disease, but from infectious or inflammatory diseases and their consequences.

This happens as a result of the fact that the kidneys cannot fully perform their tasks and the human immunity is greatly weakened. As a result, any infection or virus can cause irreparable harm to health even with treatment.

Not every person is suitable for artificial blood purification, so a fairly high percentage of deaths occurs in the first year. If the human body functions normally for a year, then in 76% he will live for at least 5 more years, subject to all the requirements of the doctor.

Complications in hemodialysis

Since the kidneys are an important system for cleansing the body, disturbances in their functioning cause problems with the work of other internal organs. Complications may include:

arterial hypertension;
anemia;
CNS lesions;
bone diseases;
hyperkalemia.

Arterial hypertension is an increase in blood pressure. If such a problem occurs, the doctor prescribes a special diet. If the problem is not solved in a timely manner or started, then it can contribute to the development of a heart attack or stroke.

Anemia is a decrease in the concentration of red blood cells in the blood. This reduces the saturation of the body's cells with oxygen. Anemia is caused by a lack of erythropoietin, which is produced by healthy kidneys. The reason for the development of this condition is also large blood loss or lack of iron and vitamins in the diet.

Disorders in the work of the nervous system suggest a decrease in the sensitivity of the limbs. This condition can be caused by diabetes mellitus, a lack of B12, or an excess of toxins in the blood.

Bone disease occurs when kidney problems are advanced, when the body cannot get vitamins and minerals from the blood. The patient has brittle bones and severe bone destruction because the kidneys cannot allow calcium to be absorbed more easily by converting vitamin D.

In addition, there is a deposition of excess calcium and phosphorus. As a result, there ulceration and inflammation.

Pericarditis is an inflammation of the pericardium, or lining of the heart. This happens when fluid accumulates around the organ, which causes a decrease in blood output and heart rate.

An increase in the concentration of calcium in the blood or hyperkalemia occurs when the diet is abandoned during hemodialysis. Its peculiarity lies precisely in reducing the consumption of this mineral with food. If the concentration of potassium in the blood increases, then this may become cause of cardiac arrest.

To prevent the development of complications, you must:

strictly follow the diet;
monitor personal hygiene;
consume a strictly limited amount of liquid;
take prescribed medications on a timely and regular basis;
inform the doctor if symptoms of complications;
undergo regular check-ups;
timely take the prescribed tests.

If all preventive measures are followed, the risk of complications is minimized.

At home - is it possible and how?

It is allowed to carry out hemodialysis at home. Requires a special device that is designed specifically for home use. Some of them are quite large, but modern models are small and weigh from 4 to 7 kg and can be fixed on the body.

The advantages of the procedure at home are relative safety, since the device is used by only one person. In addition, dialysis can be carried out at any time and there is no need to correlate the schedule with the opening hours of the clinic and the doctor.

The disadvantages of home hemodialysis are the need to train a loved one to work with the device. At first, it is necessary to carry out the procedure under the supervision of a visiting medical worker. In addition, the cost of the device for home use is high and amounts to about 15-20 thousand dollars.

kidney transplant

Hemodialysis is prescribed for people suffering from kidney failure. Procedure cannot completely replace an organ, so the condition of the person is gradually deteriorating. In addition, the disease requires regular examinations by a doctor and visits to the hospital for the procedure.

Modern medicine allows some patients to improve their quality of life with a donor kidney transplant. The method is quite complicated and the risk of organ rejection is high. In addition, waiting for a donor organ can last for years, and after a transplant, a person will take drugs that depress the immune system until the end of his life.

Peritoneal dialysis

Peritoneal dialysis is also artificial blood purification method. But for its implementation, not an artificial material (membrane) is used, but a part of the human body or its peritoneum. It is a thin membrane that covers the internal organs of the abdominal cavity.

The advantages of this method of dialysis are that the peritoneum, unlike the membrane, has a more selective permeability and allows substances with a higher molecular weight to pass through it. Thus, more types of toxins pass through it.

The procedure is carried out quite slowly. The dialysate itself is placed in the patient's abdominal cavity and blood is filtered through it through the vessels in the walls of the peritoneum.

The advantage of the method is its ability to be used by patients with end-stage renal disease, as well as in the absence of the possibility of installing a fistula.

For the procedure, an improved apparatus and peritoneal catheters are used, which provide high-quality drainage of the abdominal cavity. The catheter is fixed with a Dacron cuff in the subcutaneous fat. The catheter is inserted surgically.

This procedure may have some complications. The main ones include peritonitis or inflammation of the peritoneum. Other features are about the same as with standard hemodialysis.

The procedure is usually carried out while the patient is in the hospital, because requires constant medical supervision to change the dialysate and monitor the health of the patient.

Nutrition and diet

Carrying out hemodialysis provides for strict adherence to certain dietary habits. They consist in lowering the intake of products into the patient's body, which can increase the rate of endotoxin production.

The main principle of the diet is the restriction of fluid intake by the patient. Per day, his kidneys can produce from 500 to 800 ml of diuresis. However, overall weight gain must not exceed 2.5 kg. If there is an increase in fluid loss with sweat, then the amount of fluid consumed may be slightly higher.

An important feature of nutrition in chronic renal failure and acute renal failure is complete rejection of salt or its minimal use. It is allowed to eat no more than 8 g per day.

Find out the principles of treatment for acute renal failure in our article.

In addition to limiting the intake of salt and salty foods, it is necessary to limit the intake of foods rich in potassium. Their list is as follows:

bananas;
citruses;
dried fruits;
potatoes and some vegetables;
natural juices;
bran;
greens;
cereals;
chocolate;
cocoa;
nuts.

If a person counts the amount of potassium consumed, then its volume per day should not exceed 2000 mg.

As in the case of potassium, you should limit the intake of foods with phosphorus (fish, cheeses, etc.).

With the above restrictions, a person should eat quite varied and receive enough protein and energy.

Adhering to a diet, it is also necessary to take into account the individual characteristics of the body, as well as follow the recommendations of the attending physician.

In case of any problems, it is necessary to contact him immediately in order to avoid deterioration of the condition.

How the process of hemodialysis is carried out, see in detail in the video:

opochke.com

What is an "artificial kidney"

The artificial kidney device is designed to purify the blood from toxic elements that accumulate in the blood due to insufficient excretory function of the organ.

The use of the device helps to normalize the electrolyte and acid-base balance, remove toxins from the body in case of poisoning, as well as excess water in case of swelling.

How the machine works

The manipulation is carried out by a nephrologist in a hospital or in specialized hemodialysis centers.

Types of devices

pumps supplying heparin and pumping blood;
instruments showing pressure;
air bubble prevention device.

systems for air elimination, temperature control;
mixing devices, filtration monitoring;
dialyzer blood leak sensor.

Module 3 is a filter and a hemodialysis membrane.

There are devices that can be used on an outpatient basis. This is a portable artificial kidney machine designed for home use. Its technical capabilities are lower than those of stationary devices, but it performs the main function (blood purification). Such devices are worn on the belt and weigh up to 7 kg, they perform dialysis at any time of the day when the patient needs it. The duration of the manipulation is 3-4 hours.

The use of the device is characterized by the following features:

safety (the risk of infection is excluded);
ease of use;
manipulation at any time of the day.

These are the positive aspects of the device. The negatives include the following:

high price of the device;
control of health workers during the first sessions;
the need for training.

Who should not use the device

The procedure has its contraindications. It can not be done to patients with such pathologies:

mental illness;
oncological pathologies;
leukemia or anemia;
pathology of the central nervous system;
advanced age (over 80 years);
diabetes mellitus (age after 70 years);
having more than two serious diseases.

It is impossible to carry out the procedure for patients suffering from alcoholism or drug addiction, having an active form of tuberculosis, predisposed to the development of massive bleeding.

Unwanted Effects

After or during the procedure, patients may develop undesirable effects:

The appearance of complications becomes a reaction of the body to the behavior of manipulation. If the patient does not adhere to a diet, these side effects become more. Patients with renal insufficiency are prescribed a diet that strictly prohibits alcohol, spicy, spicy and smoked foods, limiting the intake of salt and fluids. If the rules of nutrition are violated, the patient creates an additional burden on the kidneys, since an increased amount of salt retains moisture in the body, leads to the formation of edema, increases the load on the heart muscle, and contributes to arterial hypertension.

Conclusion

Renal failure requiring continuous hemodialysis is a very serious disease. There are no exact statistics to determine how long a patient who is on forced blood purification will live. But nevertheless, carrying out the procedure, along with observing the rules of dietary nutrition, as well as normalizing the motor regimen, will prolong the patient's life. But how much - depends on the individual characteristics of the organism and concomitant diseases.

nefrologinfo.ru

Indications and contraindications

The procedure carried out by this device is called hemodialysis and is used in the following cases:

If the patient is diagnosed with acute or chronic renal failure.
In case of poisoning with drugs or alcohol.
In diseases that contribute to the accumulation of fluid in the body (edema of the lungs, brain, heart failure)

This procedure is prescribed in cases where conservative methods of treatment do not give positive results.

Despite the fact that hemodialysis is a fairly simple procedure, it still has a number of contraindications such as:

The presence of any chronic diseases.
Diseases of the nervous system.
Epilepsy.
Tuberculosis of any form.
Hepatitis.
Cirrhosis of the liver.
Oncological diseases.
Heart attacks, strokes.
Age over 70 years.

How is the device

Dialysis can be performed both at home and in special medical centers and takes from 4-5 hours, the frequency of procedures depends on the type and complexity of the disease. Before starting, the patient undergoes a medical examination, takes tests, measures his pressure and pulse, and is also weighed.

The device is designed to purify venous blood from toxins and toxins; it is connected to the patient's veins and with the help of a pump, the blood moves to a special membrane, and on the other hand, a dialyzer solution is supplied to purify it. The structure of the membrane and the composition of the dialyzer fluid directly depend on the disease of the patient and take into account the individual characteristics of his body.

People who are prescribed dialysis not as a one-time procedure, but as a treatment method, need to follow a special diet that limits:

Fluid intake.
Foods that contain large amounts of potassium and phosphorus.
Strict restriction of salt intake.

Inpatient or outpatient use of the device takes place under the guidance of medical personnel in equipped rooms.

To create a comfortable environment for patients, scientists have invented a portable device for dialysis. True, the price of this device is very high. And before using it, the patient needs to be trained.

Patients suffering from chronic renal failure very often require an organ transplant, but due to the lack of donor organs and cases of rejection of foreign organs by the patient's body, an implant replacing the kidney was invented.

Possible Complications

Due to the fact that most often the devices are used to remove fluid from the body, various side effects occur:

Decrease or increase in blood pressure.
Fatigue appears.
Drowsiness.
Nausea and vomiting appear in connection with a decrease in pressure.
Headaches that are associated with pressure drops.
Cramps in the limbs.
An increase in temperature caused by infection in the body.

With what force such symptoms will manifest itself directly depends on the amount of fluid excreted from the body.

Despite the possible complications, this procedure has saved many lives.

pochkizdorov.ru

general information

American inventor John Abel created the device in 1913, which is the prototype of the modern artificial kidney. The device was first used in 1944 by medical scientist William Kolf. The device for hemodialysis has a fairly voluminous size. Now, in order to undergo a blood purification procedure, a person must be in the hospital for several hours at least 2 times a week. This procedure cleanses the blood of waste by an average of 60%.

Acute or chronic renal failure can be fatal. The condition is extremely dangerous and requires immediate surgical intervention, the creation of an apparatus - an "artificial kidney" - has become the only salvation for patients with a similar diagnosis. Without changing the volume of blood in the body, the hemodialysis device ensures the elimination of toxic compounds, while normalizing water-salt metabolism and blocking the occurrence of arterial hypertension.

What is the installation

Medical experts note that when acute renal failure, pulmonary edema or extensive intoxication of the body is detected, purification is carried out through a special filter that mimics the true kidney membrane.

The use of the device is justified if the kidneys have ceased to cope with the function of processing blood and removing harmful substances from the body. At the same time, the amount of toxins in the human body increases, which causes the death of brain cells. This happens due to insufficient supply of oxygen to the brain.

Blood, passing through the equipment, is cleared of harmful substances:

urea and its compounds;
creatinine (a product of chemical compounds in muscles);
poisonous compounds of fungi and plants;
medicinal and narcotic drugs;
alcohol compounds (methyl and ethyl);
excess liquid.

The frequency and duration of the procedure depends on the stage of development of the disease, how advanced it is. As a rule, the patient needs 2-3 sessions per week, which take approximately 4-5 hours. During this time, the concentration of urea in the body is reduced by 70%, the condition of the person as a whole improves.

Hemodialysis procedure

To carry out the hemodialysis procedure using a portable device or stationary equipment in the clinic, it is necessary to prepare the patient in advance. The fact is that many hours of pumping out and pumping fluid through the patient's vessels can significantly spoil their condition. As a rule, the blood vessels in such patients are already unhealthy, but the device will increase their wear and tear significantly.

To solve this problem, if the human vessels do not allow you to connect equipment without harm to them, there are several ways out:

creating a hole in the body (it is formed from an artery and a vein, its location is usually on the forearm);
sewing in a catheter (usually in the groin, the operation is performed under local anesthesia).

After carrying out this or that procedure, the patient is strictly prohibited from physical overstrain and lifting heavy objects. The advantage of a catheter sewn into the body is the possibility of its immediate use.

The measurement of pulse and pressure is considered necessary procedures, without which they are not connected to the installation. New portable devices and medical equipment are able to take readings on their own. Also, a person should measure their weight to assess the swelling of the tissues by the doctor and an approximate measurement of the volume of fluid pumped out.

Slag pollution and toxins are forced out of the body by creating excess hydrostatic pressure in the vessels. By squeezing the liquid through a semi-impermeable filter, the device completely cleans it and returns it back to the vessels, healthy.

The portable device is equipped with a small pumping station that supplies blood to a container with a filter. When it enters the reservoir, it is cleaned with a special solution and returns to the venous system without harmful impurities. After a few hours of operation of the device, the patient's blood becomes clean. The procedure is often repeated after 2-3 days. This ensures the normal functioning of a person suffering from kidney diseases.

The procedure for cleansing the kidneys using hemodialysis is prescribed to the patient if the organs have lost their functionality and work at only 10-15%. Violations are confirmed by manifestations of unpleasant symptoms (vomiting, nausea, rapid fatigue, swelling). The device is able to take over part of the functions of the kidneys, while controlling a person's blood pressure and normalizing the water-salt balance. There are a number of conditions when hemodialysis is necessary:

cessation of blood supply;
severe blood loss;
severe injuries;
infections after abortion;
inflammation of the kidneys with the cessation of the outflow of urine;
blockage of the urinary arteries.

Before cleansing, the attending physician evaluates the patient's well-being, determines the functionality of the kidneys, the state of the respiratory system, liver, and heart. A prerequisite is the performance of laboratory blood tests.

Principle of operation

The device for hemodialysis cleans the patient's venous blood from accumulated toxins and slags. To do this, the equipment must be connected to the patient's vein and artery system. With the help of a built-in pump, the blood gradually moves to the membrane, from the back side comes the dialysis solution for purification. The blood is cleaned with a solution of harmful substances and, already healthy, it enters back into the system.

Filling with dialysate equipment occurs strictly before the procedure. The solution is prepared in advance, taking into account the individual characteristics of the patient. The device creates a composition of distilled water and a concentrated product on its own. After the procedure, the effect of the drug is evaluated by medical specialists according to several indicators.

Types of equipment

The desire to improve the quality of life and not to “fall out” of the general rhythm drives all patients affected by kidney diseases. They want to work, take care of family and household chores, without being distracted for a long time. For these purposes, manufacturers have created a device - an artificial portable kidney. With the help of this device, the patient conducts cleansing in the familiar environment of his own home on his own, choosing the right time.

However, the cost of this equipment is high and unacceptable for a large percentage of people. Therefore, in the arsenal of doctors there are still varieties of devices that are used in a hospital setting.

portable device

The portable artificial kidney was developed by Western scientists and was shown to the world only 10 years ago. The main advantage of the device is its weight of 3.8 kg and portable battery operation. The equipment works at home, takes 4 hours, and the person feels much more comfortable than in a hospital.

The operation algorithm of this installation does not differ from the principle of operation of stationary equipment. The blood is purified through the membrane using a solution. Connection occurs through a fistula or catheter and does not take much time. Cleaning, if necessary, is carried out around the clock.

How much does such a device cost? Today, a portable device is still very expensive and not everyone can afford to buy it.

implantable device

Implants will soon become commonplace, due to the extensive use for patients with chronic renal failure. The dialysis unit is especially in demand due to the shortage of donor organs and the increasing cases of rejection of "live" organs by the patient's own cells. This is a salvation for people suffering from incurable kidney pathologies.

Today, an American developer company is conducting equipment research in professional laboratories. The compact device will perform filtration functions, cleansing the kidneys of harmful substances, toxins and toxins. In this case, the energy necessary for the operation of the device will be generated due to the flow of blood flow. Information on how much such an installation will cost has not yet been reported.

Donor organ transplant

Chronic renal failure is treated by transplanting a donor organ from another, healthy person. This is a surgical procedure where the patient's own organ is removed and replaced with a functioning kidney.
As a rule, substitution therapy is used in the last stages of the following diseases:

Donor organ transplantation can prolong the patient's life for a long time and improve the quality. This is a life-saving operation for children with congenital kidney problems, as constant hemodialysis inhibits the development of the baby.

Surgical intervention is performed only in cases where the donor organ is suitable according to the patient's parameters. Today, the percentage of organs that have not taken root is extremely high, so the development of artificial implants is considered a discovery that will allow medicine to reach a new level.

Contraindications for the procedure

Hemodialysis is a necessary procedure for maintaining the life and normal existence of a large number of people suffering from severe kidney disease. But the use of the device is not allowed for every patient, there are a number of contraindications:

severe arterial hypertension;
acute viral and bacterial infections;
blood clotting disorders;
open tuberculosis.

Provided that the disease threatens the life of the patient, the artificial kidney apparatus is still connected, despite one or several contraindications at once. This decision is made to prolong the life of the patient.