What Is the AV Fistula & Why Was It Revolutionary?

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The arteriovenous fistula invented in 1963 by general surgeon Kenneth Charles Appell at the Bronx Veterans Administration Hospital is considered by many experts to be one of the top medical breakthroughs of the 20th century, an advance in kidney dialysis that in the 46 years since has saved and improved the quality of many, many millions of lives around the world.

Basically, an AV fistula is a little tunnel created between an artery (hence “arterio”) and a vein (“venous”). In some cases it may be due to disease or birth defect, but Dr. Appell’s landmark achievement was to create such a connection surgically so as to provide the best vascular access possible. That’s absolutely critical for effectively dialyzing kidney patients – it allows blood to be more effectively pulled from the vein for filtering and purifying in a dialysis machine, then returned to the vein using the blood pressure from the connected artery. It’s usually applied to a patient’s arm -- generally the forearm -- but can also be elsewhere (for example, the leg or shoulder); it requires an operation taking an hour or two, followed by several weeks of healing before it can actually be used in dialysis. Dr. Appell’s original procedure was actually a type of AV fistula called a radial-cephalic fistula, between the radial artery and the cephalic vein near the wrist.

Before Dr. Appell conceived the AV fistula while working at New York’s Bronx Veterans Administration Hospital nephrology unit, hemodialysis was a painstaking and downright painful procedure with a high failure rate. The method used was the Scribner shunt, invented by a University of Washington team and named after its internist member, Belding Scribner, in 1960 and used in conjunction with the Kolff artificial kidney, invented in the early 1940s by Willem Kolff in the Netherlands. But the Scribner shunt used tubing and a catheter (Dr. Appell’s innovation was “native,” using the patient’s own blood vessels), and so it had many problems, including bleeding, infection, erosion, clotting, and the need for the patient to have a bulky dressing in order to maintain sterility.

Today there are more than 300,000 end-stage renal patients being dialyzed around the world. Referring to them in a recent interview, Lawrence Spergel, a physician working with an organization called Fistula First, asserted that the AV fistula “is truly their lifeline; without an adequate vascular access they cannot survive.”

However, a growing problem has arisen in recent years (and one that’s the reason for the existence of Fistula First, which works with the U.S. Department of Health and Human Services): that moving away from the “native fistula” invented by Dr. Appell and – ironically – back toward the concept of the Scribner shunt. Too many doctors have been convinced to rely on commercially profitable arteriovenous grafts and venous catheters made of plastic; unlike these, the native AV fistula is non-patentable (so no big bucks, sorry!). Though these methods provide more profits to the companies that have patented them, they’re far less wonderful for patients: they’re shorter-lived, need more repairs, have higher rates of infections, and cause more hospital stays.

Bottom line: Kenneth Appell’s original invention is still the gold standard in kidney dialysis.