WHAT IS AV FISTULA AND HOW SUCCESSFUL IS IT?
An AV fistula is an artificial surgical connection between an artery and a vein. It makes a vein fat, thick and strong to sustain dialysis needle.
Worldwide success rate (that is a fistula through which uneventful dialysis is initiated) is 60-70%, but with ultrasound screening we can get better results.
WHAT PRECAUTIONS ARE TO BE TAKEN IN A FISTULA LIMB?
No prick, blood sampling, blodd pressure recording is to be done on the fistula arm. Tight garments, sudden jerky movements to be avoided. A person can carry on normal day to day gentle activities.
WHAT ARE ADVANTAGES OF A FISTULA AND WHAT RULES ARE TO BE FOLLOWED?
In a AV fistula a patients own vein and artery is used. Hence chances of infection, foreign body reaction is minimal to nil. It can be done under local anaesthesia . If one fistula fails over a period of months to years a second fitula can be done without much morbidity.
PERMCATH AND TUNNELLED CATHETERS WHERE DO THEY STAND AS OPTION?
A permcath or tunnelled catheter goes into the main vein to which all veins of our hand orleg enters. These cathters are easy to place, easy to handle, lasts for few months to a year and easy to get dialysis done. But kept for long they can cause severe infection and narrowing and can choke the main vein and thereby stop all options of future AV fistula or graft.
Permcath therefore should be used in patients in whom fitula or graft is not possible or has failed or patient needs immediate dialysis and has no fistula.
WHAT ARE LIMITATIONS OF AV FISTULA?
A fistula requires 6-8 weeks time to mature. Thereby it is always advisable to get an early fistula done , when the patient has deteriorating renal function and may require dialysis in 2-3 months time. Once a patient is already on dialysis if he chooses to get a fistula done, he will require an additional dialysis line for 1-2 months at least.
WHAT IS ROLE AND LIMITATION WITH AV GRAFT?
An artificial tube may be used in patients whose veins are not good for AV fistula. This graft can then be used for dialysis needle puncture. However cost, infection and foreign body reaction limits its use and should be used only in patients if fistula has failed or not possible.
SMALL DIALYSIS CATHETERS ARE EASY CAN BE REPLACED – SHOULD WE USE THEM?
Temporary dialysis lines should be used as least as possible , since they are notorious for infection and lasts only for few weeks.They go into the main vein and thereby if we choke these veins no future AV Fistula, Graft, Permcath will be available in future
WHAT PROBLEMS CAN WE FACE WITH ACCESS?
A fistula or graft may narrow down or get choked by clots over time. They can be dilated by a balloon or cleared by surgery and reused again.
Sometimes extreme hand swelling can be due to choked main (central ) vein and require balloon dilatation of main vein (Central Venoplasty)
