Dialysis is a very important and life-saving procedure. It is performed to replace kidney function in case of renal failure. Wastes and extra fluids in the blood are filtered out during this process. To be able to perform Dialysis, the connection between the patient’s bloodstream and the equipment for performing Dialysis (dialyzer) outside the body is established. This connection is created through Dialysis Access Surgery. It is a type of Vascular Surgery which forms the vascular opening for access during Dialysis. Thus, Dialysis Access Surgery is the lifeline for the survival of the patient.
Types of Vascular Access for Dialysis-
There are three types of Vascular Access for Dialysis: Arteriovenous (AV) Fistula, Arteriovenous (AV) Graft, and Venous Catheter.
● Arteriovenous (AV) fistula is a surgical connection of an artery to a vein. An AV fistula is usually placed in the upper arm or in the forearm. It causes extra blood to flow into vein making it grow large. A larger vein hence provides easy access to blood vessels. An AV fistula is preferred over other methods as it lasts longer than other methods of access and provides a good flow of blood. Moreover, it is less prone to infection and blood clots than other methods. Before an AV Surgery, a Vessel Mapping Test is sometimes performed for assessing the blood vessels most suitable for Dialysis. An AV fistula is performed under local anaesthesia and requires two to three months for maturation before hemodialysis. If it fails to mature, the procedure is repeated.
● Arteriovenous (AV) graft is performed when AV fistula fails to mature. It is hence the second most preferred choice for long-lasting access to vascular tissues for Dialysis. An AV graft is a looped plastic tube which establishes a connection between an artery and a vein. Like AV fistula, AV graft is also performed under local anaesthesia. It is slightly more difficult to maintain than an AV fistula.
● A venous catheter is used for short- term hemodialysis. It is a tube which is inserted into chest, neck, leg, or near groin for vascular access. After exiting the body, the tube splits into two halves. In the case where a renal disease has made quick progression leaving little or no time for the AV fistula or AV graft to mature, a venous catheter is used to establish the required vascular connection. This procedure is also performed under local anaesthesia. It is a tool for emergencies but is not suited for long- term use. It can cause narrow vein due to an infection,
scarring, or blood clot. If long- term venous catheter is used, it is tunnelled under the skin which has fewer problems associated with it and is more comfortable.
How to Care for a Vascular Access?
● Get checked for infections and other problems before each hemodialysis session;
● Use the operated site for access only for the intended use;
● Always keep the access clean;
● Prevent cutting or bumping the access;
● Check for thrill/ vibration in the access and inform the doctor if any;
● Do not put pressure on the access site;
● Do not put blood pressure cuff around the access arm;
● Do not wear jewellery or tight-fitting garments over the site;
● Do not lift a weight.
Vascular Surgery for Dialysis is performed to provide vascular access for the procedure. AV fistula is the most preferred type followed by an AV graft. A venous catheter is recommended to be used only in case of an emergency when there is not much time left for the other two options to mature.