The term chronic renal failure (CRF) refers to the progressive and irreversible loss of kidney function. This progressive failure is characterized by a gradual increase in serum creatinine concentration in parallel with a decrease in glomerular filtration rate. In general, the goal in modern treatment is to establish renal replacement therapy by dialysis or kidney transplantation. Before the patient develops advanced symptoms of uremia. Therefore, patients who have reached end-stage renal disease (ESRD) or End Stage Renal Disease. At this low level of kidney function, the physician can predict with reasonable certainty that without replacement therapy, uremia will occur.
Pathophysiology: As kidney function decreases, the end products of protein metabolism that are normally excreted (through urine) accumulate in the blood, resulting in uremia.
The accumulation of excess water, waste products, and electrolyte imbalances that result from kidney failure can damage other organs and endanger a person’s life. For this reason, it is necessary to filter and remove excess water and waste products from the body.
The word dialysis or dialysis is a process in which water and waste products are separated and removed from the blood.
Today, kidney replacement methods are performed in two ways: intermittent dialysis and peritoneal dialysis for patients with chronic kidney failure, and intermittent dialysis is performed with the help of advanced devices. Which include hemodialysis (HD), hemofiltration (HF), hemodiafiltration (HDF) and low-efficiency dialysis (SLED) techniques. First, a central venous access is inserted for the person. Then, the blood is removed from the person’s body by a blood pump, passes through the filter, and is returned to the person’s body again. Blood purification and purification and excess body water are performed inside the filter.
HD hemodialysis: The most common blood purification method is hemodialysis, which is based on the movement of substances according to the law of diffusion. In this method, substances with low molecular weight are removed from the filter according to the concentration difference between the blood and the dialysis solution and are thus cleaned from the blood.
However, the spectrum of waste materials accumulated in the blood is not limited to substances with low molecular weight.
HDF hemodiafiltration: The newest blood purification method in the world that is performed today for patients with chronic kidney failure is hemodiafiltration. In this method, blood purification is not limited to substances with low molecular weight, but substances with medium and large molecular weight are also removed from the blood. For this purpose, a sterilized solution is added to the blood and removed from the blood again. The circulation of the solution in the blood ultrafiltration helps to remove substances with high molecular weight. At the same time, two methods of convection and diffusion create the highest and closest efficiency to the kidney.
Advantages of hemodiafiltration (HDF) over conventional dialysis:
• Reduction in per capita consumption of drugs, phosphate binders, and anemia medications
• Improvement of bone status, appetite, nutrition and reduction of the burden of disability of dialysis patients
• Much better water quality and reduction of the incidence of dialysis complications and treatment readmissions
• The need to use fistula as venous access to provide adequate blood flow, which in the long term prevents complications from temporary or permanent catheters.
• Proof of greater effectiveness and cost-effectiveness in studies conducted around the world and keeping up with current science
• Greater possibility of being on the kidney transplant list due to improved cardiovascular status and anemia
• Possibility of shortening dialysis time due to very high efficiency, increased center capacity and efficiency of working patients
• Fewer cardiac events, fewer infections and less need for hospitalization
• Improved quality of sleep, patients’ lives and a significant reduction in the rate of outpatient visits
Nutritional recommendations for patients undergoing hemodiafiltration treatment:
- In order to prevent an increase in blood sodium, salt and foods containing it should be avoided.
- Consumption of foods high in potassium should be completely limited. Basically, all foods, especially fruits and vegetables, contain a lot of potassium. Accordingly, the consumption of some fruits and vegetables that are very high in potassium will not be allowed in patients undergoing hemodialysis treatment. However, in patients undergoing hemodiafiltration treatment, the consumption of these substances will be allowed in small amounts.
- Due to the high levels of phosphorus and protein, the consumption of dairy products is very limited in patients undergoing hemodialysis treatment. However, patients undergoing hemodiafiltration treatment are allowed to consume one glass of milk or yogurt during the day and 30 to 60 grams of cheese.
- Protein foods such as meat, chicken, eggs and fish should be consumed in limited quantities and according to the recommendations of nutritionists.
