Dialysis: what it is. Renal failure, the stages of chronic kidney disease, and the two types of therapy with their pros and cons.
Dialysis: what is it? What are the types? When is it necessary? These are the most frequently asked questions regarding this type of therapy. First, it is necessary to clarify what dialysis is.
It is a procedure whose main purpose is the removal of waste products that the body produces. It also serves to remove excess fluid from the blood when the kidneys can no longer perform their function. Therefore, when kidney function is reduced by more than 85%.
An additional task of dialysis therapy is to ensure the integration and balance in the blood of important minerals such as bicarbonate, potassium, phosphorus and calcium.
Dialysis therefore has the function of purifying the blood from toxins that derive from drugs and protein metabolism. It also rebalances the salts that regulate blood pressure and regulates the pH level of the blood.
What is Dialysis and when is it Necessary
Dialysis therapy becomes necessary in cases of severe chronic kidney failure. Particularly when it reaches the fifth stage. This is referred to as uremia and the term derives from urea, the substance produced by protein metabolism that is not eliminated from the blood due to kidney dysfunction.
The accumulation of waste and fluids in the body can cause severe illness and even death in the most serious cases. Dialysis therefore performs a purification function.
Chronic Kidney Failure
Chronic kidney disease consists of a reduction in normal kidney function. Kidney failure manifests in different stages depending on the severity of the problem. The early stages do not present symptoms, but there are treatments that reduce its progression.
Therefore, prevention or early diagnosis are fundamental to avoid the onset of chronic kidney disease or the worsening of the condition.
Kidney failure is analyzed through the measurement of a specific parameter. The Glomerular Filtration Rate (GFR). The glomerular filtration value that indicates normal kidney function is 100-120 ml per minute (120 ml/min).
Therefore, monitoring the glomerular filtration rate allows for early diagnosis of the disease onset. Additionally, the measurement of creatinine levels is fundamental.
Stages of Kidney Disease
There are 5 stages of chronic kidney disease. In the first two, symptoms generally do not appear and primary prevention of the disease is possible.
In stage 3, which is divided into stage 3a and 3b, chronic kidney failure is already present because there is a clear reduction in GFR. The first symptoms include bone pain, malnutrition and difficulty concentrating.
In stage 3a, the nephrologist intervenes to reduce complications and alterations typical of stage 3b. In the latter, anemia, acidosis and hyperparathyroidism occur more frequently. In stage 3 in general, drug therapy is necessary combined with a low-protein diet and strict blood pressure and glycometabolic control.
In stage 4, symptoms involve an evident reduction in physical strength and endurance. The patient must follow a more restrictive diet and needs erythropoietin supplementation to better treat anemia.
Stage 5 is the final and therefore most severe stage of kidney failure. It is characterized by a GFR below 15 ml/min and the nephrologist establishes a pre-dialysis pathway. Subsequently, they will evaluate various clinical conditions to initiate dialysis: high levels of azotemia and creatinine, high values of potassium, phosphorus and parathyroid hormone, urination frequency, edema. Dialysis is initiated when these levels are not kept under control through drug therapy and specific diet, with the risk of complications for the heart and other organs.
Duration of Dialysis
Dialysis therapy can be performed for a determined period of time in cases where the kidney failure to be treated is temporary. Therefore, when regular kidney function resumes, dialysis can be discontinued.
Conversely, when the dysfunction is chronic and has reached an advanced stage, therapy continues until kidney transplantation is necessary. In these cases, dialysis allows the patient to avoid complications until a donor is ready for transplantation.
Another case involves patients who cannot undergo transplants. The impediment may depend on age or general health conditions. For these patients, dialysis will continue for life.
What is Dialysis and What are the Two Types
The nephrologist can propose two types of dialysis therapy. Hemodialysis (extracorporeal) and peritoneal dialysis (intracorporeal). There are three characteristics common to both types of dialysis. First, blood circulation which in hemodialysis occurs through an external circuit. The dialysis fluid receives waste and excess fluids in the blood through a process called diffusion. In peritoneal dialysis, purification occurs through the capillary circulation of the peritoneum.
Finally, there is a membrane that acts as a filter and separates the blood from the dialysis fluid. Its purpose is to retain cells and useful substances in the blood. In hemodialysis, this membrane is essentially an external dialysis filter; in peritoneal dialysis, the peritoneum itself performs this function.
Advantages and Disadvantages of the Two Types of Dialysis
There are advantages and disadvantages that characterize the two types of dialysis therapy. Regarding hemodialysis, the advantages are essentially related to timing and application methods.
Pros and Cons of Hemodialysis
Hemodialysis is performed three times a week in sessions of approximately four hours. The sessions take place in appropriately equipped centers, in the presence of specialized healthcare personnel. Regarding the procedure, healthcare professionals can establish a specific vascular access that minimizes the risk of complications.
The most frequent complications during treatment are hypotension, cramps and arrhythmias.
The disadvantages of hemodialysis primarily concern conditioning in planning travel or trips. Although there has been a developing trend to plan trips and vacations in places that have rapid connections with nephrology and dialysis centers. An additional disadvantage concerns the limitation in fluid intake. Finally, hemodialysis is not feasible at home but exclusively in specialized centers.
Pros and Cons of Peritoneal Dialysis
The first advantage of peritoneal dialysis is that, being daily, it subjects the body to less stress. It can also be performed at home, without the need to go to a specialized center. Finally, the patient will not have time constraints, because it can be planned and performed according to their needs.
Rather than disadvantages, for peritoneal dialysis we can speak of fundamental requirements. Starting with the need to have an intact peritoneum. Additionally, it must be performed under perfect hygienic conditions for the patient and the environment in which it is performed. The catheter inserted in the abdomen to perform this type of dialysis must not get wet.
The negative aspects concern the risk of peritonitis and greater glucose absorption with consequent weight gain for the patient.