Hemodialysis - Causes, Symptoms and Treatment .MF .
hemodialysis - a method of cleansing the blood by selective removal of toxins through artificial semipermeable membrane.It is used in patients with acute and chronic renal failure.
«Father» hemodialysis considered Scottish chemist of Graham, who in 1856 described the process of diffusion, which both described as "dialysis."By the process of diffusion movement he understood soluble substances of low molecular weight through a semipermeable membrane from a concentrated solution (urine) in less concentrated (distilled water).For the first time in human hemodialysis session held Georg Haas in 1911 in Strasbourg.As filters used for blood purification membrane in colloidal form of thin tubes.As a means of thinning the blood, first used giruidin (a drug derived from the secretions of the salivary glands of the medicinal leech), and then heparin (an extract from the liver of cattle).Designed Haas dialysis machine differed impressive size.It consisted of eight cylindrical containers filled with dialysis fluid,
Haas Apparatus for hemodialysis.
In the period from 1926 to 1928, he spent about 20 sessions of hemodialysis for patients with acute renal failure.Each session lasted approximately 60 hemodialysis minutes.Unfortunately, all of the patients died within a short time of intoxication and blood poisoning.
In 1943 W. Kolff cellophane membrane was first used as filters.Fifteen patients with acute renal disease after hemodialysis died.It was only the sixteenth patient after two sessions held by dialysis to survive, kidney failure was cured.This method of treatment was strongly criticized by members of the scientific community.Only the invention of J. Merril flame photometry - the method for the assessment of the chemical composition of the blood, significantly reduced patient mortality from water and electrolyte balance disorders.
Currently widespread dialysis in medicine helped save the lives of millions of patients with acute and chronic renal failure.
Indications hemodialysis procedures
Carrying hemodialysis shown under the following conditions.
• uremic symptoms (due to the accumulation of harmful substances in the blood that are not displayed in kidney disease) intoxication: nausea, repeated vomiting, weakness, mild fever, unstable blood pressure.
• excess fluid, which manifests itself in the form of edema resistant to treatment, as well as an increase or decrease in blood concentrations of potassium, sodium, chlorine.
• severely impaired kidney function: glomerular filtration rate below 10 ml / min (in children and in patients with diabetes less than 15 ml / min).
• decompensated acidosis - a condition associated with an increase in blood acidity (pH) of less than 7.35.
• life-threatening swelling of the brain and lungs, associated with intoxication.
hemodialysis for chronic hemodialysis are the following contraindications:
• marked decrease in blood pressure associated with significant blood loss or release of large amounts of urine, for example, in the initial period in the nephrotic syndrome.
• bleeding disorder with a high likelihood of breakthrough bleeding
• cardiovascular disease in the decompensation stage, at which the hemodialysis session can dramatically complicate the patient's condition.
• active inflammatory process, such as tuberculosis of the internal organs, sepsis.
• cancer metastasis
• mental disease patient.
In an emergency session for acute hemodialysis no contraindications.
Acute hemodialysis session is indicated for patients with acute renal failure in a critical condition.As a rule, it is carried out in the intensive care unit.The amount and frequency of procedures determined by the severity of the patient.As a rule, it is the daily long sessions.Under favorable conditions possible recovery of renal function defective or completely, or, in severe cases, the development of chronic renal failure.
Chronic hemodialysis is performed in patients with end-stage chronic renal failure.To perform this test there is no need for hospitalization.Patients go home at outpatient centers or dialysis department on the basis of the hospital.After the procedure, they return home, that is their quality of life is practically not reduced.
To perform hemodialysis patients need to connect to the device "artificial kidney".Pre-patient forms a temporary or permanent vascular access.Temporary vascular access, such as catheterization of large veins (subclavian, jugular, femoral vein) in modern conditions only apply for the emergency procedure.
central catheter in the subclavian vein.
prohibited their long-term use due to their possible festering with prolonged standing and development of catheter-related sepsis.
Currently, the gold standard for adequate vascular access is the formation of arteriovenous fistula.Typically, during operation crosslink radial artery (forearm fistula) or brachial artery (shoulder fistula) the saphenous vein.As a result, the vein is carried out under a high pressure discharge of blood from an artery.Wall vein thickens, its lumen becomes wider, Vienna does not fall down when a large blood sampling speed.
This process is called arterizatsiey veins.This results in the ability to puncture the vein thick needles for hemodialysis.
to permanent vascular access statement applies to permanent (permanent) catheter and bypass surgery.Indwelling catheters specially treated to prevent infection, and if used properly serve several years.When bypass artery and Vienna joined a synthetic prosthesis.Permanent catheters and arteriovenous shunts are preferred in case of impossibility of the formation of the natural arteriovenous fistula, for example, when the Scatter type structure or a very thin vessels bringing artery.
apparatus "artificial kidney" is a product in the form of a small unit, a saturated electrical and hydraulic systems which guarantee safe and efficient process for purifying the blood of toxins.
modern apparatus "artificial kidney".
Modern mobile phones are distinguished by easy operation and maintenance.Each apparatus "artificial kidney" consists of several blocks.circulation unit includes pumps that provide blood flow to the dialyzer.Standard hemodialysis session is held with the flow rate of 250-350 ml / min.The dialysate mixing unit is provided with ultrapure water and salts in the concentrate to a certain proportion the finished dialysis solution preparation.The correct composition of the dialysis solution plays an essential role in ensuring the safety of the patient during dialysis.Extracorporeal unit includes a dialyzer and krovoprovodyaschie highway.Dialyzer - is the filter, which is a process of purifying the blood of toxins and saturation of its nutrients.
Appearance capillary dialyzer.
main characteristics of the dialyzer is the active surface area, the magnitude of which depends directly on the cleaning ability and the method of sterilization of the dialyzer.The presently preferred are dialyzers, sterilized by gamma irradiation or hot steam.According to current recommendations, the reuse of dialyzers is not recommended.The most safe and effective are now considered capillary dialyzers with synthetic membranes of polysulfone, heliksona, poliamiksa et al.
management and control system of blood purification consists of a plurality of sensors, the main task of which is to ensure an effective process for purifying the blood and patient safety.
Currently, we recommend that the sessions of chronic hemodialysis 3 times a week for at least 4 hours.dialysis time, blood flow rate and type of dialyzer are calculated based on body weight, age, presence of residual renal function in a patient.
With a team of emergency medical services, special transport or self patient comes to the place of hemodialysis.In the locker room leaving outerwear, dresses in a clean change of clothes and shoes, rises in the dialysis room.Before each weighing procedure medical personnel of the patient (for the estimation gain in fluid interdialytic period) measures blood pressure, heart rate estimates, some other physical characteristics.At steady state the patient's doctor decides to start hemodialysis.
Carrying hemodialysis in the dialysis room.
to connect to the device "artificial kidney" vein puncture is made in the area of the fistula, prosthesis, or in the presence of the catheter connection krovoprovodyaschih highways with the catheter port.When filling the highways with blood to prevent blood clots administered heparin.During hemodialysis medical personnel going evaluation of the patient (blood pressure, heart rate, body temperature), and if necessary correction of the treatment program.
After the session, the patient is weighed (to assess the amount of fluid intake and determine the "dry" weight, ie weight without excess fluid), received a doctor's recommendation to interdialytic period, and goes home.
Once a month the patient's blood sample is taken, which provides a measure of blood purification and, if necessary, to adjust the program hemodialysis.Also, when a blood test to determine the concentration of hemoglobin, red blood cells, hematocrit, iron metabolism in the body to determine the further tactics of treatment of anemia, as well as calcium, phosphorus, parathyroid hormone and vitamin D metabolites for correction of calcium and phosphorus metabolism.Every 6 months, a determination of hepatitis B and C, HIV and Treponema pallidum in the blood of patients.All patients who receive hemodialysis, must necessarily be vaccinated against Hepatitis B and C, if necessary may conduct other laboratory and instrumental analysis, as well as expert advice.
Possible complications of hemodialysis
Despite its apparent simplicity, each hemodialysis session is a serious procedure, which can easily lead to serious complications.
• drop in blood pressure are among the most frequent complications of hemodialysis.Contributing factors are advanced age and associated diseases of the circulatory system.Typically, blood pressure decrease associated with high volume or rate of fluid intake during dialysis.Treatment is carried out by reducing the intake of fluid and recovery options deficit.
• Increased blood pressure and is a serious complication that is left untreated can lead to heart attack or stroke.In the treatment of hypertension is becoming a priority adequate fluid intake and the use of hypertensive drugs.
• Muscle cramps, usually associated with excessive fluid fence.Treatment consists in fluid selection and termination of the introduction of the solutions hypertonic with respect to blood plasma.
• Nausea and vomiting are associated with a drop in blood pressure, as well as dysfunction of the gastrointestinal tract.Treatment should be directed to the increase in blood pressure, administration of anti-emetics, treatment of opportunistic diseases of the gastrointestinal tract.
• Often headache on dialysis is associated with high or low pressure.Treatment consists of correction of blood pressure and the administration of pain medication.
• The temperature rise is usually associated with infection or reaction biocompatibility.If you suspect a communicable disease is shown receiving antimicrobials.
• Reaction biocompatibility - it is the response of the human body on contact with blood components of the apparatus "artificial kidney".It appears in the form of allergic reaction type anaphylactic shock or pyrogenic reaction that is accompanied by fever, reduced amounts of leukocytes, back pain.Anaphylactic shock is characterized by a pronounced drop in pressure, breathing difficulties and demands the immediate cessation of dialysis and emergency care.When pyrogenic reactions shown using dialysis continued symptomatic treatment.Subsequently, the recommended detection material to which the reaction occurs in the patient, and replacing it safer analogue.
• Patients with severe complications such as disekvilibrium syndrome, arrhythmia, swelling of the brain and lungs, should be under the supervision of specialists in the intensive care unit.
term of life of patients during hemodialysis is an average of 10-15 years in compliance with the water-drinking regime, adequate vascular access and the right tactics treatment.
physician therapist, nephrologist Sirotkin EV