What are Dialysis Interventions?
Dialysis interventions are interventional radiology procedures that use image-guided minimally invasive techniques to treat blocked arteries and veins and improve blood flow inside the arteriovenous graft or fistula of dialysis patients. An arteriovenous fistula is a surgical connection made between an artery and vein. An arteriovenous graft is a surgical connection of an artery and a vein using a synthetic tube. The graft or fistula is usually made in the non-dominant arm and allows easy exchange of blood between the vein and the dialysis machine.
Anatomy of the Kidneys
The kidneys are a pair of bean-shaped organs that are part of the excretory system present on both sides of the spine behind the abdomen. Their main function is to filter the blood by eliminating waste materials in the form of urine and maintaining the overall body fluids. Each kidney contains millions of special functional units called nephrons where the blood filtration takes place. Urine accumulates at the funnel-shaped opening of the kidney called the renal pelvis and from there moves to the ureter and is excreted from the body through the urethra.
Indications of Dialysis Interventions
Indications of dialysis interventions include:
- Narrowing of AV fistula or graft
- Thrombosis of AV graft
- Chronic kidney disease
- Kidney injury
- Blockage in dialysis fistula or graft
Preparation for Dialysis Interventions
Preparation for dialysis intervention includes:
- Analyzing and evaluating liver and kidney function
- Ordering tests to check if your blood clots normally
- Temporary stoppage of regular medications only if instructed by your doctor
- Wearing a patient gown before the procedure
Procedure of Dialysis Interventions
For the dialysis intervention procedure, x-ray imaging equipment, a catheter, a stent, a guidewire and a sheath is commonly used. The different types of dialysis intervention procedures include:
- Angioplasty and Stenting: This procedure is done to remove the blockage in the blood vessels. Using x-ray imaging a thin catheter with a balloon at its tip is inserted into the AV fistula or graft. The balloon is inflated as it reaches near the blood clot. This expands the blood vessel and increases the blood flow. A stent, made of metal mesh is placed inside to keep the blood vessel expanded.
- Catheter-directed Thrombolysis: This technique is used to remove abnormal blood clots. A thin catheter is inserted into the blood vessel and guided to the thrombus with the help of x-ray imaging. Clot-dissolving medication is passed through the catheter which dissolves the thrombosis or the blood clot is physically broken up by a mechanical device passed through the catheter.
- Fistulogram: This is a diagnostic procedure in which catheter tubes are placed inside the blood vessel and a contrast dye is injected into the blood vessel that helps to visualize the blood clot on X-ray imaging. The identified blood clot or thrombus can then be removed by either angioplasty and stenting or thrombolytic therapy.
Post-procedure of Dialysis Interventions
After the procedure, you will be taken to the recovery room and will be kept under observation. Your doctor will insert the catheter tube and perform dialysis. Inform your doctor in case of any discomfort. You will be provided with pain medications if necessary.
Risks and Complications of Dialysis Interventions
Some of the risks and complications of dialysis interventions include:
- Bleeding
- Allergy to the contrast dye
- Infection
- Damage to artery or vein
- Pulmonary embolism