Nothing has created more confusion recently than the subject of buttonholes in dialysis access, and nothing is more untrue than the oft-expressed misconception that “Dr. Webb doesn’t like buttonholes”.
Very superficial vein, right under the skin visible at the top of the image. Very high risk for erosion and bleeding, and not suitable for buttonholes.
Abandoned buttonhole in brachiocephalic fistula with breakthrough bleeding.
Buttonhole pseudoaneurysm – this is not a fibrous “tract”, it is a wide mouthed “pocket”. Note how close this extends to the skin.
Cross section of previous image. Note the wide mouth of the pseudoaneurysm – caused by using a different angle with every cannulation, wearing out the vessel wall rather than creating a fibrous tract.
Ideal vein for buttonholes – sizable, borderline deep under skin visible at top of image, but not too deep to hit, healthy depth of buffering subcutaneous tissue.
In fact, Dr. Webb likes well-created buttonholes in appropriate patients. They can be very helpful in patients with borderline deep fistulas. They can also be dangerous, and lead to loss of an otherwise well-functioning fistula, or t0o dangerous bleeding.
To create a buttonhole, two or more discrete and optimal spots for cannulation are identified, and then they are carefully cannulated with sharp needles in exactly the same spot, and in exactly the same angle every time dialysis is performed. Scar tissue forms around the needle, and in this way, a chronic fibrous tract is created. Once established, a blunt needle can be inserted into the tract like a plug in a socket. In theory, this can help prevent wear in the fistula and aneurysm formation from overuse of limited zones of cannulation.
Some limitations exist. Buttonholes should NOT be used in PTFE grafts, or stented portions of fistulas due to the risk of bacteria being introduced down to the graft or stent and creating an infection. We have seen grafts get infected from inappropriate use of buttonholes. Likewise, buttonholes should not be established through areas of laminated clot (old clot lining the wall of a fistula), or through pseudoaneurysms, as both of these are more likely to get infected. Buttonholes should never be placed through scarred areas where the skin is not movable over the fistula, as a z-track is essential to prevent post cannulation bleeding. And buttonholes are overly hazardous where the fistula is very close to the skin, as can happen with superficialized or transposed fistulas (image #1).
Technique in creating the buttonholes matters. If the needles are not placed in exactly the same place and at the same angle, you may just be puncturing the fistula over and over in a small area, wearing it out, and creating a small pseudoaneurysm under the skin.
Buttonhole pseudoaneurysm can manifest themselves as small annoying spots that rebleed unpredictably between sessions, even after being abandoned. Suturing these does not allow these to heal – they have to be stented from the inside or surgically repaired (images #2, #3 and #4).
Other buttonhole pseudoaneurysms can appear as rapidly expanding bubbles that burst and bleed big time. One such patient appeared in our office after several years away with a marble sized dark bump at her buttonhole site, and was directed to go straight to the ER. She chose to go home first instead, and blew out in her car. She received CPR in the street, spent a week in the ICU getting transfusions, and then rebled and lost her fistula entirely. She is lucky she survived.
Borderline deep fistulas are probably the best for buttonholes (image #5).
We recommend that patients with buttonholes have them examined every six months, or whenever there is a problem, no matter how minor. Minor problems can become major problems in a hurry.
In summary, buttonholes are a valuable tool in selected patients. Not all patients will be able to have buttonholes, no matter how much they want to dialyze at home. A high degree of vigilance is recommended to prevent the progression of small problems into bigger problems.
A resource for the dialysis community:
Showing you things you want to see;
Discussing things you want to know;
All about dialysis access.
Frequently asked questions,
And Dr. Webb’s blog.
Comment and criticize
Spread the news in the dialysis community
Like us on Facebook
Contact Us with your vote using the form below: