Peritoneal dialysis - Causes, symptoms and treatment. MF.

Peritoneal dialysis is a method of artificial purification of blood from toxins, based on the filtration properties of the patient's peritoneum.

Peritoneum is a thin shell that completely or partially covers the internal organs of the abdominal cavity. In physical terms, the peritoneum is a membrane with a selective permeability for various substances. Peritoneum has three types of pores: small, water-permeable, medium, for passage of water-soluble compounds and substances with a low molecular weight, and large - for substances with a large molecular weight. Due to the large penetrating ability of the peritoneum it is capable of transmitting various kinds of toxins. This distinguishes the method of peritoneal dialysis from hemodialysis, in which only substances with small and partially average molecular weight pass through the membrane.

With dialysis, dialysis solution( dialysate) is located in the abdominal cavity and filtration of toxins from the vessels in the peritoneal wall is constantly carried out. Within a few hours the dialysate becomes contaminated with toxins, the filtration process stops, which requires replacing the solution.

The rate and volume of filtration is a constant, the purification process is slow and long, which allows the use of peritoneal dialysis in patients with low or unstable blood pressure and in children. In addition to filtration during peritoneal dialysis, excess fluid enters the solution. This process is called ultrafiltration. The dialysate contains an osmotic active substance, for example, a concentrated glucose solution, which attracts the liquid by a concentration gradient. As a result, excess fluid from the bloodstream through the peritoneal vessels enters the dialysate solution. In addition to glucose, as an osmotic agent in some dialysis solutions there are amino acids, dextrose, glycerol, starch. In addition, dialysate contains a complex of chemicals, selected according to the needs of the patient.

Indications for peritoneal dialysis

Peritoneal dialysis is recommended for patients with terminal stage of chronic renal failure.

Peritoneal dialysis is preferable to hemodialysis in the following cases:

• for patients in whom it is not possible to create adequate vascular access( persons with low blood pressure, expressed by diabetic angiopathy, small children).

• For patients with severe cardiovascular disease, in whom conducting hemodialysis sessions can lead to complications.

• For patients with bleeding disorders, which are contraindicated in the use of anti-thrombotic agents.

• For patients with intolerance to synthetic membrane filters for hemodialysis.

• For patients who do not want to depend on the hemodialysis apparatus.

Contraindications to peritoneal dialysis

Peritoneal dialysis contraindicated in:

• Presence of adhesions in the abdominal cavity, as well as an increase in the internal organs, which limits the surface of the peritoneum.

• With established low filtration characteristics of the peritoneum.

• Presence of drains in the abdominal cavity in a number of located organs( colostomy, cystostomy).

• Purulent skin diseases in the abdominal wall area.

• Mental illness, when the patient is not able to properly conduct a peritoneal dialysis session.

• Obesity, when the effectiveness of blood purification for peritoneal dialysis is questioned.

Procedure for peritoneal dialysis

Kit for carrying out peritoneal dialysis includes containers( empty and with a solution) and conducting lines.

Kit for peritoneal dialysis.

Also during the procedure, cyclists are used. The cycler is a device that provides programmable cycles of filling and draining a solution, and is also capable of heating the solution to the desired temperature and weighing the fused dialysate to estimate the volume of the removed liquid.

Diaphragm for peritoneal dialysis.

Peritoneal catheters are used to access the abdominal cavity.

Peritoneal catheters.

Catheters should provide good drainage of the abdominal cavity, tightly fixed, and have protection against infection. Adequate irrigation of the abdominal cavity is due to the high speed of the bay-drain solution. The catheter is tightly fixed in the subcutaneous fat due to the germination of the dacron cuff with a connective tissue. This also creates a barrier to infection. The catheters are made of silicone or polyurethane. The catheter is placed surgically into the pelvic cavity. The outer part of the catheter is exposed under the skin on the anterior or lateral surface of the abdominal cavity. Appearance of patient with peritoneal catheter.

After placement of the catheter for adequate fixation, it should take 2-3 weeks, then proceed with the conduct of dialysis sessions.

For carrying out peritoneal dialysis, it is necessary to attach the dialysate-filled container to the catheter. Schematic representation of a peritoneal dialysis session.

This process occurs when hygienic and antiseptic rules are observed, including the treatment of hands, working surfaces, skin around the catheter, and the junction of the mains and the catheter( adapter), putting on the face mask. The front surface of the abdomen is freed from clothing, a clean cotton towel is tied to the waistband. A sterile bag is taken out of the empty empty bag and the container with fresh dialysate solution. In this case, the container with fresh solution is hung on a tripod at a height of 1.5 m, and the discharge bag is put on the floor. The mains after processing with an antiseptic solution are interconnected.

The solution is initially drained into an empty bag. Then this part of the highway is pinched, the clamp is opened on the bringing branch of the highway. A new dialysis solution is poured into the abdominal cavity. After this, the clamps on the lines are pinched, the empty container and bag with the drained solution are removed. The external port of the catheter is closed with a protective cap, fixed to the skin and hides under the clothes. Every month, patients take blood and fluid from the abdominal cavity for examination. Based on the results, a conclusion is made about the degree of purification of blood, as well as about the presence or absence of anemia, of phosphorus-calcium metabolism disorders, and, on the basis of these indicators, correction of treatment takes place. On average, the exchange sessions are 3 times a day, the volume of the dialysis solution is 2-2.5 liters.

In case of poor tolerance, failure to comply with the regimen, insufficient blood purification, and also in case of severe or recurring complications, the patient should be referred for hemodialysis.

Complications of peritoneal dialysis

The most dangerous complication of peritoneal dialysis is peritonitis( inflammation of the peritoneum).The most common cause of inflammation is the failure to comply with the rules of antiseptic during exchange sessions. Peritonitis is diagnosed with two of three signs:

• External manifestations of peritoneal inflammation: abdominal pain, fever, chills, general weakness, nausea, vomiting, stools.

• Turbid peritoneal fluid.

• Detection of bacteria in peritoneal fluid.

Treatment: broad-spectrum antibiotics up to test results, then antibacterial drug taking into account the sensitivity of the identified microorganisms to it. In addition to specific therapy, temporary discontinuation of peritoneal dialysis sessions, abdominal rinsing with a standard dialysis solution or Ringer-lactate solution is recommended. In solutions during washing, heparin is added, which prevents the adhesive process in the abdominal cavity. In severe cases, you may need to remove the peritoneal catheter.

Non-infectious complications include the following:

• Violation of the operation of the abdominal catheter with difficulty in filling / draining the solution. This complication can be due to changes in the location of the catheter, closure of the catheter by the intestinal loop, for example, with constipation, by bending the catheter, or by closing the lumen of the catheter with blood clots or fibrin, which is common in peritonitis. When closing the lumen of the catheter with clots, you can try to rinse it with a sterile isotonic solution. In case of failure, replacement of the catheter is indicated. Complications associated with changing the position of the catheter require surgical intervention.

• With the bay and the dialysis solution in the abdominal cavity increases intra-abdominal pressure, which contributes to the formation of hernias. The most common are hernia of the white line, less often umbilical and inguinal hernia. Depending on the size and directivity of the hernial protrusion, the question of further treatment is resolved: surgery or expectant management.

• Expulsion of the peritoneal solution to the outside or to the subcutaneous fatty tissue usually occurs immediately after the placement of the intra-abdominal catheter, or with poor catheter fixation in the elderly and weakened patients. This complication is diagnosed when the bandage gets wet in the catheter standing area, or when the swelling of the subcutaneous fat tissue of the abdominal wall and genital organs is formed. Treatment consists in stopping peritoneal dialysis for 1-2 weeks for optimal fixation of the catheter, with the patient undergoing hemodialysis sessions. Under adverse conditions, replacement of the catheter is indicated.

• Right-sided pleurisy occurs in weakened patients, as well as in some patients at the beginning of treatment. This complication is associated with the penetration of the dialysate through the diaphragm into the pleural cavity. Treatment - reducing the volume of the solution being poured. To prevent this condition, it is recommended to conduct exchange sessions in a vertical state. With increasing respiratory insufficiency, the patient's transfer to programmed hemodialysis is shown.

• Abdominal pain, not associated with inflammation of the peritoneum, often occurs at the beginning of treatment and after a couple of months passes. Pain, as a rule, is associated with irritation of the peritoneum with a chemically active dialyzing solution, or as a result of overextension of the abdominal cavity with a large amount of solution. In the first case, the treatment consists in selecting the dialysate, which is optimal in chemical composition, in the second case - filling the smaller volumes of solutions with increasing multiplicity of exchanges.

Many specialists consider peritoneal dialysis as the first stage of replacement therapy for patients in the terminal stage of renal failure. In some patients, for a number of reasons, peritoneal dialysis is the only possible method of treatment.

In comparison with hemodialysis, peritoneal dialysis allows patients to lead an active lifestyle, engage in work. But, unfortunately, the duration of treatment with peritoneal dialysis directly depends on the filtering properties of the peritoneum, which, gradually, gradually decrease, with frequent peritonitis. In this case, there is a need for alternative methods: hemodialysis or kidney transplantation.

Physician therapist, nephrologist Sirotkina EV