Protecting Your Hemodialysis Vascular Access

There is an increased focus on vascular access in our health care delivery system. Several major government initiatives underway are focused on improving vascular access outcomes. The Center for Medicare and Medicaid Services (CMS) has set goals for vascular access improvement that include increasing fistula rates and decreasing the number of patients dialyzing through a central venous catheter (CVC). All of these programs stress the importance of team involvement, with you as the patient being the central member of that team. By presenting you with information about your vascular access, how it works and how to care for it, you can become an empowered patient ready to make informed decisions about your own vascular access care.

Types of Vascular Access for Hemodialysis
Fistula:
A fistula is a natural type of vascular access where your own vein is surgically connected to an artery. The increased blood flow that results from this connection causes the vein to enlarge; the vein walls strengthen. Because the fistula resides completely under the skin, it is called an “internal vascular access.” Needles must be used to access the bloodstream for dialysis. Overall, the fistula is the preferred vascular access for hemodialysis, because of its low complication rate and longer life-span as compared to other vascular access options available.

Graft: A graft is a synthetic tubing surgically connected to your blood vessels. Just like the fistula, it too resides completely under the skin and therefore is called an “internal vascular access.” Needles must be used to access the bloodstream for dialysis. Because a graft is constructed of artificial materials, it is more likely to develop complications and does not have as long a life-span as a fistula does.

Catheter: A catheter (also known as a central venous catheter, CVC) is a tube-like device that is inserted into a vein, usually in the neck or groin. Because two small tubes with caps permanently lie outside of the body while the catheter is implanted, it is called an “external vascular access.” The remainder of the catheter (the part you do not see) travels under the skin and into a vein. Ultimately, the internal end of the catheter rests in the top chamber of the heart. In order to access the bloodstream for dialysis, the two outside tubes are connected to the dialysis machine. Because so much of the catheter resides outside of the body, it is exposed to many more risks, including infection. The relatively higher level of risk associated with a catheter makes it the least desirable type of vascular access. It can potentially lead to many complications and is therefore intended to serve only as a short-term vascular access until an internal one can be established.

Physical Assessment of Your Vascular Access
Your access allows you to receive your life-saving dialysis treatments. Because of this, it is commonly referred to as your “lifeline.” A well-functioning access is necessary to achieve maximum dialysis efficiency. When dialysis treatments become inefficient or “inadequate,” toxins accumulate in the body and cause your quality of life to significantly decrease.

Early detection of access malfunction with prompt treatment will serve to extend the life of your access. Changes within your access are oftentimes subtle and take weeks, even months, to develop. Because of this, it is critical to consistently engage in frequent monitoring of your access. Since your access is always at your disposal, you are in the position to notice changes in it, especially the subtle ones, long before they evolve into serious complications. Patients that have adopted the “Look, Listen and Feel” process of physical assessment often quickly realize how vital frequent monitoring truly is. By following the three steps as outlined below, you can familiarize yourself with your access, its functionality and how to properly care for it.

Step 1: Look
Inspect the skin over your access. Changes in skin color, swelling, redness and enlarging bumps are not normal. Allow scabs over previous cannulation sites to completely heal – do not disrupt them. Cannulation is the practice of inserting a dialysis needle for the purpose of hemodialysis.

Step 2: Listen
Listening to your access and knowing the meaning of the sounds you hear can help you detect many of the common complications accesses experience. To listen to your access, listen with the ear opposite of the access. Alternatively, a stethoscope is an ideal instrument to use for this exercise. Affordable stethoscopes are widely available and can be purchased at a local medical uniform store or through a variety of online retailers. When listening to a fistula or graft, you will hear a whooshing sound called a “bruit.” The bruit should always be a low-pitched, continuous sound. Position your ear or stethoscope over the incision line and move up the entire length of the access. The bruit should be strongest at the incision line and should gradually fade as you move up the access.

Step 3: Feel
Run your hand gently across your access. You will feel a distinct buzzing feeling known as a “thrill.” Starting at the incision line where the artery and vein were connected to form your access, run your hand across the entire length of the access. The thrill should be strongest at the incision line and should gradually fade as you move your hand up. If you have a fistula, it should feel soft and can be compressed easily. If you have a graft, it will feel firm and tube-like.

NOTE: A strong pulse in the fistula or graft without a gentle thrill is not normal.

Common Vascular Access Complications
Stenosis:
Process by which gradual narrowing inside a fistula or graft causes blood flow through the access to be significantly limited. 

There are two key ways to identify whether you have a stenosis forming. During your dialysis treatment, a stenosis oftentimes causes arterial and venous pressure alarms on the dialysis machine to sound frequently. Be aware of these alarms, what they indicate and how often they ring.

Secondly, a stenosis can also affect the amount of bleeding you experience after your dialysis treatment is complete. Prolonged bleeding for more than 15 minutes after the needles have been removed from your access is generally not normal and can be a sign of a stenosis developing.

Having a stenosis can also cause difficult cannulation. If you experience more pain than usual when your dialysis needles are inserted or removed, let your dialysis caregiver know. If left untreated, a stenosis can evolve into a thrombosis which will completely stop your dialysis until it is resolved.

Thrombosis: Process by which an access becomes clotted and all blood flow through the access is blocked.

A thrombosis can be best detected by regularly listening and feeling the access and becoming familiar with your bruit and thrill. A loss in bruit and thrill are key signs that a thrombosis is present. Oftentimes, a thrombosis also creates a great deal of pain in the access and surrounding areas.

It is crucial that a thrombectomy (declot) be performed as soon as possible when a thrombosis is present. Timing is critical in resolving a thrombosis. When more time passes before a thrombosis is resolved, the likelihood of being able to perform a successful declot decreases significantly. Additionally, the thrombus will keep the access from being used for dialysis and will lead to catheter placement.

Aneurysm: A localized bulging out of the fistula wall or breakdown of graft material. 

An aneurysm is visible on the skin surface as a localized bump or bulge in the access. The presence of an aneurysm is cause for concern especially if the size of it increases or if the skin over it becomes thin or shiny.

Infection: Presence of bacteria in the vascular access and/or bloodstream. 

Remember to always give careful attention to your general health. Experiencing fever or chills are tell-tale signs of an infection. An infection can also cause changes in the appearance or feel of your access. Redness, draining pus, swelling or localized pain around the site of your access, or even inside your access, can be signs of infection.

Notify your nephrologist and/or dialysis caregivers immediately if you detect signs of thrombosis or infection.

General rules of access care:

  • Keep the skin over your access clean.
  • Avoid sleeping on your access arm.
  • Protect your arm from injury.
  • Do not allow IVs, blood pressures or blood draws done on access arm.
  • Wear loose clothing and avoid jewelry over the access.

The Role of the Dialysis Caregiver:

  • Engage in meticulous hand washing and glove changing.
  • Look, listen and feel the access before every treatment.
  • Always perform proper site preparation prior to cannulation.
  • Rotate cannulation sites to prevent breakdown of vessel or graft material.
  • Check catheter exit site for signs and symptoms of infection prior to start of treatment.
  • Ensure that both patient and caregiver wear masks when opening catheter caps.

Your vascular access is precious and we want to help you keep it healthy. Remember – take good care of it and it will take good care of you!

Christina Beale, RN, CNN, Director, Outreach and Education for Lifeline Vascular Access, has more than 20 years of nursing experience, including seven years in education and program development as well as quality management. For the last two years she has focused on vascular access education. Christina is a member of ANNA, NKF, ASDIN, AAKP and the ESRD Network 7 Advisory Committee. She describes herself as a passionate patient and dialysis caregiver advocate. 

Diane Peck, RN, CNN, Nurse Education Manager for Lifeline Vascular Access. Diane worked for three years in Critical Care prior to entering the world of nephrology. She has spent 29 years working in all modalities of dialysis including management and education. She is an active member of her local ANNA chapter education committee. She is a true patient advocate who never says “no” when it comes to working on a project related to CKD outcomes improvement. 

This article originally appeared in the January 2011 issue of aakpRENALIFE.