Dialysis is a common treatment practice for those who are suffering from kidney function failure. The dialysis process helps in removing the wastes and excessive water content from the blood artificially, with the support of machines, which is otherwise the task of the kidneys.
Different Types of Dialysis
There are different types of dialysis. All of these types help in purifying the blood in some way or the other. Depending on the method used, the types of dialysis vary. There are three major or primary types of dialysis and two secondary types. They primary types of dialysis are:
The most common method of dialysis is the Haemodialysis. In this method, the doctor will create a vascular access into the body, surgically. This will allow more blood to flow through the dialyzer and return back to the body after purification. The vascular access is an entrance to the blood vessels.
Inside the dialyzer, there are thousands of tiny synthetic fibres that act as semi-permeable membrane. A dialysis solution, also known as dialysate, is used to purify the blood that runs through this membrane of fibres. A negative pressure is used to remove the water from the blood to the dialysate. The usual span for the Haemodialysis process is 4 hours. Typically a person has to undergo three haemodialysis sessions per week. However, depending on the condition, requirement or disease, haemodialysis can be done more frequently and for shorter or longer sessions.
The body size and the amount of waste in the blood determine the frequency of haemodialysis suitable for the patient. Usually the procedure is done at a doctor’s office or at a hospital or at a dialysis centre. Nowadays, with advanced technology, haemodialysis is also being offered at the patient’s home. Those, who are in need for a long-term dialysis, are recommended the at-home haemodialysis treatment.
This is a surgical procedure of dialysis. The doctor implants a catheter into the patient’s belly and this comes out from below the belly button. A dialysate fluid is inserted into the abdomen through the catheter. This fluid draws out the waste materials and extra water from the blood, through the small blood vessels in the abdomen. Once the process is done, the waste materials and extra water from the blood along with the dialysate fluid, all get deposited into a bag through the catheter.
Here it must be mentioned that there are two types of peritoneal dialysis –
- Continuous ambulatory peritoneal dialysis (CAPD)
- Continuous cycling peritoneal dialysis (CCPD)
CAPD is useful for those, who want to undergo the dialysis treatment while staying mobile or while doing other tasks. It is carried out multiple times a day. This method does not require any machine to carry out the dialysis treatment. CCPD is useful for those, who do not want any interruption throughout the day. It is done at night, while the patient is asleep.
Hemofiltration is similar to haemodialysis except for the principle which it follows. In this process, the blood is passed via the dialyzer but the dialysate is not used. The water is passed through permeable membranes rapidly, taking along with it the dissolved substances including large molecular substances which are usually not cleared in hemodialysis. During the treatment process, water and salts that are replaced during this filtration process is infused back in the extracorporeal circuit.
The secondary types of dialysis include:
- Haemodiafiltration: This is actually a combination of hemodialysis and hemofiltration.
- Intestinal Dialysis: In this type of dialysis, the diet is incorporates acacia fibre, a soluble fibre, which is easily digested by the bacteria in the colon. This bacterial growth increases the nitrogen content in the digestive system which is then eliminated from the body through feaces.
Advantages of Haemodialysis and Peritoneal Dialysis
- The main advantage of haemodialysis is that it is carried out only 3 times a week. This means that the patient has 4 dialysis free days in a week.
- With Peritoneal dialysis the main advantage is, it does not require any huge dialysis machines. Instead, it can be carried out well at home.
- If you are travelling, it is much easier to carry the portable peritoneal dialysis machine, than the Haemodialysis machine, which is huge.
Disadvantages of Haemodialysis and Peritoneal Dialysis
- Since, haemodialysis is always carried out at a dialysis clinic; so when you are travelling, you need to find a clinic that will help you to do the procedure.
- Patients undergoing haemodialysis treatment have to maintain a very strict diet. Certain foods must be avoided and there is also a restriction on the fluid intake. Some patients cannot drink more than a cup of fluid a day.
- With peritoneal dialysis, the main disadvantage is that it has to be carried out every day.
- Another upsetting matter with the peritoneal dialysis is that the catheter, almost permanently, hangs loose from the belly. Though it can be hidden under the clothes, the patient may feel uncomfortable.
Yet another disadvantage of peritoneal dialysis is that the patient has a tendency of developing peritonitis infection, along the line of the abdomen where the thin membrane of the catheter touches the abdomen. In such a case, after a few years of peritoneal dialysis, the patient has to switch to haemodialysis to avoid peritonitis. The dialysate fluid that is used for peritoneal dialysis reduces the protein level in the blood, leading to malnutrition and lack of energy. It also results in weight gain as a side effect of the dialysate fluid.
Advantages of Hemofiltration
- Hemodialysis helps in treating heart failure while hemodialysis might worsen the condition sometimes.
- Hemofiltration can lower the rate of refractory hypertension to 1% and sometimes one might also be in a position to stop antihypertensive medicines.
- The incidence of hypotension and water and salt retention in patients undergoing hemofiltration is reduced to 5%.
- Hemofiltration, either continuous or intermittent, is actually an effective treatment of acute kidney failure.
- In case of hepatic coma, hemofiltration has shown better results as compared to hemodialysis; however, it is not as effective as blood perfusion or plasma exchange.
Disadvantages of Hemofiltration
- Patient’s mobility is restricted in case of hemofiltration and the procedure requires a constant patient centred activity which hinders the resting and sleep times.
- The patient has to be on anticoagulant medicines except in cases where a patient has mechanical valve which regulates the effective running of pump.
- Many a times, fluid balance is open to various potential errors.
- Which type of dialysis would be more suitable for you, can well be decided by the doctor. The patient needs to discuss this with the doctor and choose the one as per his/her convenience.