Vascular access for hemodialysis

Vascular access for hemodialysis

• During hemodialysis blood is removed and returned via the vascular access.
• The vascular access is put in place or created before an individual needs dialysis.
• The vascular access is usually placed in the arm or chest, but can also be placed in the neck or leg.
• All forms of vascular access need ongoing care (and occasional procedures) to make sure that they continue to work

There are three types of vascular access:

1. Fistula
2. Graft
3. Central Venous Catheter

Where can the access go?

A fistula or graft can be placed in:

• the lower arm (non-dominant arm is preferred)
• the upper arm
• the upper leg

A central venous catheter is placed into a large vein in:

• the neck
• the chest
• the upper leg

Saving the veins

• Arm veins provide the best access to the blood should a fistula or graft be needed in the future
• Having blood drawn from the arm or placing an IV in the arm veins can damage those veins
• Use of hand veins is recommended
• Reminder arm bands or cards can be provided

When is the vascular access created?

• When the need for dialysis is near, a referral to the Vascular Access Clinic is made
• The clinic team includes a vascular surgeon, dialysis access coordinator and a nephrologist
• On the clinic date an ultrasound is performed on both arms to determine the size and quality of veins and arteries
• This will aid in deciding the best options for vascular access

Fistula

• The preferred access is called a fistula
• A fistula is made when an artery is joined directly to a vein
• The stronger blood flow from the artery will make the vein get larger
• It takes approximately 2 months following surgery for the fistula to get large enough for use

Graft

• If your own veins cannot be used for a fistula then another type of access called a graft is an option
• A graft is a small soft plastic tube that joins an artery to a vein
• A graft can be used 2 – 3 weeks after surgery

Fistula / graft surgery

• A pre-assessment appointment is required prior to the fistula/graft creation
• The vascular surgeon creates the fistula or graft in the operating room and usually no overnight hospital stay is required
• After the operation a dressing is applied over the surgical site and some pain, swelling and bleeding can be expected

Fistula / graft maturation

• Fistulas can be used about eight to twelve weeks after surgery
• Grafts can be used about two to four weeks after surgery

Fistula / graft care

DO:

• Check access pulse daily
• Keep access clean
• Protect access from potential injury
• Keep access arm free of tight jewelry or clothing

DO NOT:

• Do not have blood samples taken from access
• Do not have blood pressure taken from access arm
• Do not sleep with access arm under head or body
• Do not lift objects greater than ~10lbs/5kg with access arm

Fistula / graft use

• The fistula/graft will be assessed by the nurse for cannulation (insertion) sites for two needles
• The skin over the fistula/graft will be cleansed prior to needle insertion
• After insertion both needles are secured with tape
• One needle carries blood from the access to the hemodialysis machine and the other returns cleaned blood back to the body
• At the end of hemodialysis, needles are removed and gauze is applied by nurse
• Patient is required to hold and apply pressure to needle sites for approximately 10-15 minutes to stop bleeding
• Individuals on blood thinners or anti-platelet drugs like aspirin/clopidogrel (Plavix) may need to hold sites longer

• Another type of access is a central venous catheter, also referred to as a line, designed for temporary or urgent use
• This may be the only access choice for some people due to the size of their veins and arteries
• The catheter is a small plastic tube put into a large vein by a doctor in the Medical Imaging (x-ray) Department
• It can be used immediately after insertion

Central venous catheter placement

• A CVC is usually inserted by a radiologist in the Medical Imaging Department using an X-ray machine
• A dressing is applied after insertion
• A small amount of bleeding, swelling and discomfort can be expected
• A CVC can be used immediately after insertion

Central venous catheter care

• CVC dressing is changed weekly or as necessary
• Keep dressing clean and dry, however, if it becomes loose or wet, notify hemodialysis unit
• A shower cape (available at medical supply stores) and hand held shower are recommended after insertion site has healed
• Report any fever, excessive bleeding, redness or discharge from access site to hemodialysis unit as soon as possible

Central venous catheter use

• CVC is for hemodialysis ONLY
• Blood samples may ONLY be taken from CVC by a trained hemodialysis nurse
• To start hemodialysis, machine tubing is connected to both ends of central venous catheter
• One tube carries blood from central venous catheter to hemodialysis machine and the second tube returns cleaned blood back to the body
• At end of hemodialysis, both tubes are disconnected, central venous catheter is cleansed and new caps applied

Vascular access considerations: fistula

• More durable with fewer long term complications
• Lowest risk of bloodstream infections
• No restriction on swimming/bathing
• Not all surgeries for fistula creation will result in a mature/functional fistula
• Each hemodialysis treatment requires insertion of two needles
  • topical anaesthetics are available
• Bleeding and bruising can occur when fistula is needled
• Enlargement of the fistula vein is normal and may be more apparent in some individuals
  • Areas of extreme swelling (aneurysm) may develop and require surgical repair

Vascular access considerations: graft

• Considered only if the veins are too small for a fistula
• Compared with fistulas, grafts have more complications and need replacement sooner
• No restriction on swimming/bathing
• Low risk of bloodstream infections
  • Infections may require surgical removal of the graft material