A hemodialysis access or vascular access is one way to get to your blood for hemodialysis.
Hemodialysis is a treatment used when the kidneys fail (kidney disease stage 5) and can not clean the blood and remove excess fluid from the body.
If you are on hemodialysis, your access is one of the following:
- An AV fistula is made by joining an artery and vein in your arm.
- An AV graft is made using a soft tube to join an artery and vein in your arm.
- A catheter is a faint line put into a large vein, usually in the neck.
The National Kidney Foundation (NKF) recommends AV (arteriovenous) fistula as the preferred option for permanent vascular access.
AV graft is the next preferred option for permanent access. The catheter is recommended for temporary access. There may be conditions that prevent you from having a fistula or graft, and a catheter may be used.
What is a marker or hemodialysis catheter?
The catheter used for hemodialysis is a tunneled catheter because it is placed under the skin. There are two types of tunneled catheters: cuffed or cuffed. Uncuffed mined catheters are used for emergencies and short periods (up to 3 weeks).
Tunneled cuffed catheters, a type recommended by the NKF for temporary access, can be used for more than three weeks when:
- An AV fistula or graft has been placed but is not yet ready for use.
- There are no other options for permanent access. For example, a patient’s blood vessels are not strong enough for a fistula or graft.
Catheters have two openings inside; one is a red (arterial) opening to draw blood from your vein and body to the dialysis line. The other is a blue (venous) opening that allows clean blood to return to your body.
How do I care for my catheter?
Taking good care of your access will last longer and prevent problems like infection and clotting. Here are some critical steps to take:
- Keep the catheter dressing clean and dry.
- Ensure the insertion site area is clean, and your care team changes the dressing at each dialysis session.
- Keep an emergency dressing kit at home if you need to change your dressing between treatments. Ask your dialysis care team to teach you how to change dressings in an emergency.
- Never remove the cap on the end of your catheter. Air should not enter the catheter.
- You can shower or bathe if you have a transparent bandage that adheres to the catheter site and the skin around it.
- Wear a mask over your nose and mouth each time the catheter is opened to prevent bacteria from entering the catheter and the bloodstream. Professionals changing the dressing should wear a mask and gloves as well.
- The caps and clamps on your catheter should be kept tightly closed when not in use for dialysis. Only your care team should use your dialysis catheter to draw blood or give medications or fluids.
- If the area around the catheter feels sore or looks red, call your dialysis care team right away. Ask your dialysis team about signs and symptoms that need immediate attention.
- Know your Kt / V and URR (Urea Reduction Ratio). Kt / V and URR are numbers that tell you how much dialysis you are receiving. The NKF recommends using Kt / V.
If you are getting enough dialysis, your Kt / V should be at least 1.2. If URR is used, it must be 65% or more. If your numbers are too low, a possible cause may be that your access is not working well. Ask your dialysis team to verify your entry.
Should I be concerned about my catheter?
Sometimes, even when you’re very careful, your access can clot or become infected.
Clots can form inside the catheter opening or outside the catheter and block the entrance.
This can cause your blood to flow slower than your doctor ordered. If blood flow remains low for more than one dialysis treatment, the catheter should be checked and treated the same day.
Early treatment can prevent the clot from completely blocking the catheter. It is essential to restore the recommended blood flow rate and treat the lumps forming so that your catheter continues to work well and you get the amount of dialysis you need.
Infection can also occur even with a good blood flow index.
It is essential to follow the catheter care instructions exactly as you have been taught to avoid infection.
To achieve adequate treatment as quickly as possible, be informed about the characteristic symptoms of catheter infection and notify your doctor or dialysis team immediately.
Signs and symptoms of a catheter infection include:
- A cold.
- A general feeling of weakness and illness.
- Redness or tenderness around the catheter exit site.
- Drainage of the catheter exit site.
Treatment depends on the type of infection but may include:
- An ointment will be applied directly to the affected area if it is an exit site infection.
- If there is drainage from the exit site, antibiotic medication is used.
- An intravenous IV antibiotic (a solution containing an antibiotic given directly into a vein) if the infection has spread to the blood.
What happens when my catheter is not working well?
A decrease in the blood flow rate ordered by your doctor is a sign that the catheter is not working as it should. If this occurs for more than one treatment in a week, the catheter should be checked.
The lower blood flow rate will mean less dialysis. You will need a longer than regular hemodialysis treatment to get the right amount of dialysis.
Pre-pump blood pressure alarms can signify that your catheter is not working.
These sounds notify the care team that your catheter (or other vascular access) does not allow a free blood draw. This may signify that a clot is forming in the catheter, blocking blood flow.
What can be done to remove the blockage from my catheter?
Treatment is the administration of an “anticoagulant” medicine called tissue plasminogen activator (tPA). Most dialysis centers can give you the mixture while in your dialysis chair, thus avoiding a hospital visit.
If you are at the end of your treatment, tPA can be given just before your next dialysis appointment. Ask your doctor how you can arrange to receive this medicine before your next treatment session.
If the clot is not treated and signs and symptoms of a chunk are found early, the catheter may progress to wholly clotted.
You may then be asked to visit the hospital or vascular lab to have your catheter checked and possibly replaced with a new catheter.
How is the medication administered?
Your healthcare provider injects the medicine directly into the opening of the catheter.
You need to stay inside the catheter for 30 minutes to break down the clot. After 30 minutes, if not enough blood flow is restored, the doctor may repeat the process.
What are the benefits of treating the clot early?
- Hemodialysis can work as it should remove excess fluids from your body and toxins by restoring blood flow.
- There are fewer interruptions in treatment, and there is a significant improvement in the quality of life on dialysis if there is early care of the clot.
- Some additional benefits are the ability to live longer on dialysis and prevent other health problems.
What can I do to keep my catheter working well?
- Learn as much as possible about your prescribed treatment plan: your blood flow rate, how often, and how long you need treatments.
- Follow the treatment plan:
- Stay for your full treatment time.
- Keep your dialysis appointments.
- Be on time for your hemodialysis treatments.
- Ask your doctor how much dialysis you should have. Keep track of your Kt / V and URR numbers. Talk to your dialysis team if your numbers are not as good as they should be.
- Share your concerns with your doctor and your dialysis team. You may want to ask the following questions:
- How can I tell if my catheter is not working?
- What is the flow rate my doctor ordered for me?
- Why should the flow rate for my catheter be at this level?
- If my flow rate decreases, when will I be given clot-dissolving medicine?
- Does clot-dissolving medication interrupt my dialysis treatment? If so, what will happen to the rest of my treatment?
- How will you put the clot-dissolving mixture into my catheter? How long do I have to wait for it to work?
- What are the signs and symptoms of the infection?