‘Doctor, what are my options when it comes to types of dialysis catheters?’ This is a common question that I have to answer, when patients start dialysis. There are various types of dialysis catheters available in the dialysis center near you. Based on the unique needs of the patient, the correct one must be chosen.
Blood can be removed from the body for dialysis in a number of ways. This access to the bloodstream (vascular access) can be of the following types:
- AV fistula- It is made by joining an artery and a vein , generally in the arm.
- AV graft- It consists of a soft artificial tube that joins an artery and a vein
- Catheter- It is a soft tube, placed in a large vein like the Internal jugular vein in the neck.
Among the three, catheters are the topic of discussion today. Dialysis catheters are used mainly when patients need urgent dialysis. The catheters can be of two types:
- Temporary catheters
- Permanent catheters
Temporary Vs. Permanent Catheters
Hemodialysis catheters can be temporary or permanent. Based on the duration of dialysis, patient medical history, cost etc., the ideal type is chosen.
Broadly speaking, temporary catheters are used for a short period of time. These catheters are called Uncuffed catheters. They are usually used in emergency conditions or when dialysis is needed only for a few days. These are more prone to infections because the barrier for bacteria to enter the bloodstream is reduced. If a catheter has to be used for a long period of time, it is replaced by a permanent catheter.
On the other hand, permanent catheters, as the name suggests, are used for a longer time duration. They are called Cuffed or Tunneled catheters. Cuffed catheters are designed and placed in such a way that they decrease the risk of infections. This makes them safe to use. Usually, they are used while the patient waits for the AV fistula to start functioning.
Temporary dialysis catheter placement
Temporary dialysis is done for a shorter period of time. It usually starts in an emergency condition. At such a time, a temporary or uncuffed catheter is used for hemodialysis. Temporary catheters are generally placed in a large vein like the jugular vein in the neck. They can also be placed in large veins(femoral veins) near the groin crease.
The catheter is placed in the internal jugular vein in the neck. It is a major vein of our body. The catheter draws blood from it and the artificial kidney (dialyser) filters the blood.
Temporary catheter removal is done in the following situations:
1. It is the source of infection
2. The patient has improved and no longer needs dialysis
3. Temporary catheter is converted to a tunneled catheter in a patient expected to need long term dialysis.
Temporary dialysis catheters are convenient to place but they are prone to the most serious complications. Hence they should be avoided for long term use.
Permanent catheter for dialysis
In case dialysis needs to extend from the previously stipulated time or when patients are in a waiting period for AV fistula maturation, a temporary dialysis catheter needs to be replaced by a permanent one. This is mainly done to prevent the risk of infections, which is very high in temporary catheter use over more than 2-3 weeks.
Cuffed or a tunneled catheter is placed in the chest of the patient. Below the skin, the catheter is placed in a tunnel like fashion upto the jugular vein in the neck. This tunneling helps in combating the risk of infection. The cuff causes the catheter to stick to the skin tightly , thus preventing entry of bacteria into the body. The use of a cuffed catheter can be costlier than its uncuffed counterpart. However, the prevention of infection is very beneficial for the patient.
A permanent catheter or a permcath can also pose certain complications to the patient. They include pain, bleeding,infections, blockage in large veins of chest etc. However, these occur less commonly than with temporary catheter use.
Therefore, it is important to follow all the guidelines given by your nephrologist in regard to taking care of your catheter.
Fistula vs catheter for dialysis
An arteriovenous fistula is a surgical connection made between an artery and a vein. It is usually done in the forearm or the arm. This connection allows blood to go directly from the artery to the vein. In this process, the blood pressure in the vein rises. This pressure is used to divert blood into a hemodialyzer for dialysis. Since it is a surgical connection, it eliminates the use of any synthetic tubes or equipment to be placed inside the body for a long time period.
However, since fistula takes some months to mature, catheters, preferably permcath, can be used as an alternate vascular access during the time. Generally speaking, a fistula is always better than a catheter for dialysis. The rate of infection and complications reduces drastically in a fistula. It is an outpatient procedure, which allows patients to return to their day to day activities soon. The use of a fistula shows more predictable results.
However, in India, most patients are unprepared for dialysis and very few have an AV fistula ready at the time of starting dialysis. Hence, most patients start their dialysis journey with catheters.
Permanent access for dialysis
Permanent catheter can be used to replace the temporary one if the duration of dialysis increases. Typically permcath is used when vascular access is needed for more than a week.
An important thing to know regarding cuffed or permanent catheters is that they are called ‘permanent’ only in comparison to temporary catheters. Since they use tunneling to gain vascular access, they can be left in the body for longer time periods. This tunneling drastically reduces the chance of bacteria colonisation and prevents infection initially. However, if someone uses this permcath for dialysis over a long time, probably months to years, infection can still occur.
Hence, the only true “permanent” access for dialysis is the AV fistula. It is a surgical procedure and requires time to be functional. Once functional, it can be used over years for dialysis as needed. It eliminates the need to introduce synthetic materials into the body and thus reduces the chance of infection.
Dialysis port in chest
A port refers to catheters which are used to inject chemotherapy drugs in cancer patients over a long time duration. In terms of dialysis, dialysis port refers to a permanent catheter or a permcath.
Dialysis port is a vascular access though in strict medical terms, calling it a port is not correct.
Peritoneal dialysis catheters
Peritoneal dialysis is a type of dialysis which requires instilling a sterile fluid called dialysate into the peritoneal cavity of abdomen. Catheter in PD serves as a medium of introducing and removing the dialysate.
PD catheters are of two types, depending on the duration for which they are required:
- Acute PD catheter- As the name suggests, this catheter is used when peritoneal dialysis is required for a shorter period of time
- Chronic PD catheter- Chronic refers to a longer time frame. Thus, chronic PD catheters are used when PD has to be done for a longer time duration.
PD catheters are placed in the abdomen by an out-patient procedure and the patient can resume normal activities pretty soon. It is important that you understand and follow all the instructions about taking care of your PD catheter.
Before you start dialysis, be sure to understand all the vascular access options so that you can be confident about your choice. I hope this article helped answer your queries regarding HD catheters and which one to go for. All the best!