What is the Dialysis Process?
In medicine, Dialysis is also known as renal dialysis, hemodialysis, or kidney dialysis. It is the method of extracting blood from a patient whose kidney function is impaired, purifying it with dialysis, and then adding it to the patient's bloodstream. Hemodialyzer or artificial kidney is a machine, which provides a means for removing certain undesirable substances from blood or adding required components to it. By these particular processes, the apparatus may control the acid-base balance of the blood, including its content of dissolved materials and water.
Dialysis Treatment - Introduction
In 1945, Dialysis was first used to treat human patients, such as replacing or supplementing the kidneys' action in a person suffering from chronic or acute renal failure or from poisoning by diffusible substances, such as bromides, barbiturates, or aspirin. Usually, the blood is diverted from an artery, one in the wrist, into the dialyzer, in which it flows either by its own respective impetus or with the mechanical pump's aid - along one membrane's surface.
Finally, the blood passes via a trap, which removes bubbles, clots, and returns to a vein in the forearm of the patient. In persons with chronic kidney failure, who need frequent dialysis, repeated surgical access to the blood vessels that are used in the treatments is obviated by a provision of an external plastic shunt between them.
Function of Dialysis
The secretion of hormones, which affect blood pressure and cannot be duplicated, is another known feature of the natural kidney. Many modern dialyzers rely on the two physicochemical principles, ultrafiltration, and dialysis.
In dialysis, two liquids separated by a porous membrane exchange those components, which exist as particles small enough to diffuse via pores. When the blood is brought to contact with a single side of such a membrane, the dissolved substances (including inorganic salts and urea) pass via a sterile solution placed on the membrane's other side. Since the particles are too huge, white and red cells, proteins, and platelets cannot pass through the membrane.
To limit or prevent the diffusible loss of substances required by the body, such as amino acids, sugars, and required amounts of salts, such compounds are added to the sterile solution; hence their diffusion from the blood is offset by an equal movement in the opposite direction. The shortage of diffusible materials in the blood can be remedied by including them in the solution, where they join the circulation.
Although water easily passes via the membrane, it is not removed by dialysis since its concentration in the blood is less than that in the solution; indeed, water tends to pass from the solution into the blood. The blood's dilution that would result from this particular process is prevented by ultrafiltration, where some of the water, along with few dissolved materials, is forced via membrane by maintaining the blood at higher pressure than the solution.
Symptoms for Dialysis Treatment?
The following symptoms associated with kidney failure may or may not point to being indications of needing a dialysis treatment:
A sudden and/or persistent change in urination
A metallic taste in the mouth, known as ammonia breath
Itching or pruritus
Fatigue
Nausea followed by throwing up
Aversion from protein
Loss of appetite
Swelling
Types of Dialysis
Let us look at the types of dialysis and the dialysis procedure.
There exist three primary and two secondary types of dialysis, which are
Hemodialysis dialysis (primary)
Peritoneal dialysis (primary)
Hemofiltration dialysis (primary)
Hemodiafiltration dialysis (secondary)
Intestinal dialysis (secondary)
Hemodialysis Procedure In hemodialysis, the patient's blood is pumped into the dialyzer's blood compartment (using a hemodialysis machine), where it is exposed to a partly permeable membrane. Then, the dialyzer is composed of thousands of tiny and hollow synthetic fibres, and the fibre wall acts as a semipermeable membrane. Blood circulates through fibres, dialysis solution circulates around the outside of the fibres, and wastes and water circulate between the two solutions. Then, the cleansed blood can be returned through the circuit back to the body. Ultrafiltration takes place by increasing the hydrostatic pressure across the dialyzer membrane usually; this can be done by applying negative pressure to the dialyzer's dialysate compartment.
Peritoneal Dialysis In the case of peritoneal dialysis, a sterile solution with glucose (known as dialysate) is run via a tube into the abdominal body cavity around the intestine, the peritoneal cavity, where the peritoneal membrane will act as a partially permeable membrane.
Hemofiltration Hemofiltration is the same treatment as hemodialysis, but it will make use of a varied principle. The blood is pumped via "hemofilter" or dialyzer as in dialysis, but no dialysate can be used. A pressure gradient will be applied, and as a result, water will quickly pass through the very permeable membrane, "dragging" many dissolved substances along with it, including those with extremely large molecular weights that are not cleared by hemodialysis.
Hemodiafiltration Hemodiafiltration is given as a combination between hemofiltration and hemodialysis, hence used to purify the blood from toxins when the kidney is not functioning normally and also used to treat the acute kidney injury (AKI).
Intestinal Dialysis In the case of intestinal dialysis, the diet can be supplemented with soluble fibres like acacia fibre that is digested by the colon's bacteria. This particular bacterial growth increases the amount of nitrogen, which is eliminated in the faecal waste. A secondary native approach utilises the ingestion from 1 to 1.5 litres of non-absorbable solutions of mannitol or polyethylene glycol every fourth hour.
Conclusion
Did you know? Earlier, the membranes that were used for dialysis were procured from animals. It was in the late 1960s, that other materials like hollow filaments made out of synthetic and/or cellulosic materials were used for dialysis. To get more information, study materials, questions on dialysis you can register at Vedantu.com.
FAQs on Dialysis
1. Give some chronic indications of dialysis?
Chronic dialysis can be indicated when a patient holds symptomatic kidney failure and a low glomerular filtration rate (it means GFR < 15 mL/min). Between the years 1996 and 2008, there was a trend to initiate the dialysis process at progressively higher estimated eGFR, GFR. An evidence review represents either no benefit or potential harm with the early dialysis initiation that has been defined by the start of dialysis at an estimated GFR of above 10ml/min/1.732.
2. What are dialysis membranes?
The membranes that are first used in dialysis were obtained from the animals or are prepared from collodion; cellophane has been found to be very suitable, and sheets or tubes of it are used in several dialyzers. Whereas, in the late 1960s, hollow filaments of the synthetic or cellulosic materials were introduced for dialysis; bundles of that particular filaments provide a large membrane surface in fewer volumes, which is a combination advantageous in the dialyzers' devising compact.
3. What is pediatric dialysis?
Children have benefited from major advancements in dialysis management, both clinically and technologically, for over the past 20 years. Morbidity during the dialysis sessions has decreased, with the seizures being hypotensive and exceptional episodes rare. Discomfort and pain have been reduced with the use of anesthetic creams and chronic internal jugular venous catheters for fistula puncture. The non-invasive technologies to assess the patient target dry weight and access flow may significantly reduce the patient morbidity and health care costs.
4. What are the common indications of dialysis?
The decision to initiate hemofiltration or dialysis in patients with the failure of the kidney depends on many factors. These may be divided into chronic or acute indications.
5. How does dialysis help your body?
Dialysis is a treatment for patients whose kidneys aren’t functioning properly or are damaged. It is a form of treatment which involves extracting blood from an individual with a damaged kidney function and then adding it back to their bloodstream after purifying it through the process of dialysis. This whole process not only helps to purify the individual’s blood, but it also helps to maintain balance in their body by regulating as well as removing the waste along with salt and the excess fluid from their body. It also helps to maintain the person’s blood pressure and keeps certain important chemicals like potassium in their blood to a specific extent.
6. What are the advantages of dialysis? Are there any risks and side effects as well?
There are a number of benefits that result from dialysis. They are as follows:
Continuous dialysis can result in an improved and healthier well-being.
Helps to maintain a good balance of fluids and electrolytes in the individual’s body.
It is a flexible method of treatment which allows the patient to travel.
Hemodialysis also tends to carry a low risk of infection as compared to other methods.
However, there are also certain risks associated with dialysis along with some side effects. They are as follows:
Risks associated with hemodialysis include muscle cramps, anaemia, an infection in the bloodstream, itchiness, an irregular heartbeat, difficulty sleeping, and even sudden cardiac arrest in extreme cases.
Risks associated with peritoneal dialysis include high blood sugar, sudden weight gain, weakening of the abdominal muscles, frequent stomach aches, fever, and hernia.
There also remains some risks of bone disease, an overload of fluids, a drop in blood pressure (hypotension), etc.
7. What is the diet recommended to patients undergoing dialysis?
Individuals who are undergoing a dialysis treatment are recommended high-quality protein food as during the time of the treatment, it tends to produce a relatively less amount of waste during the removal. Food items like meat, fish, eggs, poultry, rice, green leafy vegetables, sweet potatoes, berries, etc., are some of the best foods to eat for a dialysis patient.
There are also certain foods to strictly avoid like processed meats, brown rice, canned foods, avocados, whole wheat bread, oranges, etc.
8. Are there any kinds of alternative to a dialysis treatment?
Although dialysis is a much recommended method of treatment for patients with kidney problems, it is also time consuming and quite expensive, which is why not everyone can access it as an option. Some alternatives to this treatment are as follows:
Anaemia management is considered to be a good alternative to dialysis. In this method, a hormone called erythropoietin or EPO is injected every week in the body of an individual whose kidneys aren’t working properly.
Continuous Arteriovenous Hemofiltration or CAVH is yet another option that one can go with instead of dialysis. It is a type of extracorporeal therapy that tends to remove the excess fluids and solutes from one’s body, only it takes more time than hemodialysis does.
A kidney transplant is also another option that can be considered.
Besides alternatives, one can also try to improve their kidney function through some natural ways like:
Managing one’s blood pressure and blood sugar levels.
Drinking plenty of water everyday.
Avoiding drinking alcohol and coffee and reducing/quitting smoking.
Limiting their salt intake.
Drinking juices like cranberry juice, parsley juice, apple juice, etc., regularly to maintain good health.
Taking probiotics.
9. List the types of dialysis.
There are five types of dialysis:
Hemodialysis: this method uses a hemodialysis machine to pump the individual’s blood into the compartment of the dialyzer, wherein it is exposed to a membrane that is partly permeable.
Peritoneal dialysis: in this method, dialysate is flowed into the abdominal body cavity with the help of a tube where the peritoneal membrane is the one that tends to act as a partially permeable membrane.
Hemofiltration: this is quite similar to hemodialysis but works on a different principle. It is often opted as an alternative to dialysis.
Hemodiafiltration: as the name might suggest, this method is based on the combination of hemodialysis and hemofiltration.
Intestinal dialysis: in this, the diet is often supplemented with the help of soluble fibres which are then digested by the colon’s bacteria. Register at Vedantu.com and download the free pdf to get well structured notes and study materials on dialysis.
