What everyone should know about dialysis access (things you’ll learn about in this article in bold):

  • How to evaluate a hemodialysis access
  • How to manage a bleeding hemodialysis access
  • How to evaluate and manage a non-functioning/clotted access
  • How to manage an infected access/fever in a dialysis patient
  • Complications of peritoneal dialysis access
  • Vascular insufficiency/steal syndrome as a result of hemodialysis access
  • High output heart failure as a result of hemodialysis access

How to evaluate a hemodialysis access:

Determine the type of access. Start by asking them details of type, when/where it was placed, any recent complications, and of course their most recent dialysis session. If their vascular surgeon works at your shop, it’s often a good idea to consult them for any complications.  

A fistula is a surgical connection between two native vessels in the patient’s arm, which has matured over months requiring plenty of time to plan and map the patient’s vessels as an outpatient (1). A graft instead is a synthetic connection between two vessels in the patient’s arm, also surgically placed but only requiring a few weeks to mature. It is prone to complications due its being a foreign body in the patient (1). Lastly, a catheter may have been placed for emergent dialysis when a patient presents late in their disease course and have not undergone mapping and access planning. These can be tunneled (placed by interventional radiology or surgery) for use as an outpatient or non-tunneled for short term/emergency use. 

 

The physical exam of a dialysis fistula or graft begins with inspection. Look for any bleeding, swelling to indicate aneurysm or pseudoaneurysm, and any recent incisions/scars. Next palpate the access, which should be soft and easily compressible throughout. It should have a soft equal palpable pulse throughout as well as a continuous thrill (or vibration) best felt at the arterial anastomosis. Lastly, auscultate the access for a bruit – normally a continuous low pitched sound indicating free flow throughout the access (2).

 

The bleeding dialysis access

Your patients is bleeding from their dialysis access. EMS wrapped them in elastic gauze wrap, and it’s soaking through. What do you do????

                  1. Compression
                  2. Compression
                  3. Compression

Controlling the bleeding is the first concern. Assessment and determination of why the bleeding occurred can be determined later when the patient is more stable. Direct pressure, ideally with one finger or small square of gauze, should be attempted for 15-20 minutes for any venous bleeding. Even some arterial bleeding will stop with this method, and if not, you will at least be able to localize the source for later intervention. If there is so much bleeding that you cannot identify the location, use your fingers at the proximal and distal ends of the access to temporarily cease blood flow while a colleague finds the source. And don’t forget to have the patient raise their arm above their head/heart or do this for them.

If this is unsuccessful, most vascular surgeons would place a “figure-of-8” stitch. Use a non-cutting needle to avoid more bleeding. 4-0 Nylon suture was recommended in one article, however most do not specify size or material (3). See this video of an ED repair (4): https://youtu.be/toFiGSfesZk

However, during our Wednesday conference many senior residents and attendings described stories of success with topical anticoagulants (think derma-bond, TXA, etc). Others mentioned in the surgical literature are thrombin and Gel foam. No one cited any particular literature evidence, but anecdotally it appeared to be very successful. The FOAM community cites many articles regarding the usefulness of these agents for other indications in the ED, extrapolating their value in this scenario (4,5,6).

Common causes of bleeding include aneurysms, pseudoaneurysms, supratherapeutic anticoagulation, and anastomotic rupture. If the bleed is small, venous, and easily controlled, then it might not be necessary to do any additional work-up in the ED. However, blood testing and arterial doppler ultrasound may be used to evaluate for these causes in the stabilized patient, in conjunction with vascular surgery when appropriate. The arterial doppler ultrasound is more likely to happen if the patient is admitted, but vascular surgery may request that you help expedite the test if it will change their management. If your patient is hypocoagulable and has an arterial bleed, consider reversal of the causative agent.

 

The non-functioning/clotted access

Patients often present from home or their outpatient hemodialysis center for issue with their hemodialysis session because their “access stopped working”. The patient should be evaluated for acute indications for dialysis that would require placement of new, emergent access. However, there are multiple tests that can be done in the ED before consulting any services to troubleshoot. These tests allow for you to determine if a stenosis/thrombosis exists that requires intervention. While differentiating venous vs. arterial may not change the need to consult vascular surgery, if both of the following tests are normal i.e. demonstrate no obstruction, then other diagnoses for failed dialysis must be considered.

The arm elevation test evaluates for venous obstruction. A normal access will collapse when the patient’s arm is elevated above their head. A stenotic/thrombosed access will remain swollen/dilated or collapse very slowly. In addition, patients with venous obstruction will have a strong pulse but diminished or absent thrill, as well as a short, high-pitched whistling bruit (2).

Patients with an abnormal pulse augmentation test likely have arterial obstruction. Normally, compression of the access distal to the access site/anastomosis should result in augmentation of the patient’s pulse when palpated proximally as well as loss of thrill. Patients with arterial obstruction will already have hyperpulsatility and therefore will have no change in pulse when the access is compressed (2).

So now you’ve determined your patient has a venous or arterial stenosis/thrombosis. What’s next? Return to your physical exam, lab results, and ECG. If the patient requires emergent dialysis, speak to your consults and determine if the access can be evaluated and managed on an urgent basis. If not, gown up for placement of an emergent dialysis access catheter. If your patient doesn’t need dialysis today, or maybe is still able to get dialysis with the limited functionality their access has right now, discuss inpatient vs. outpatient management of their obstruction. 

Consider consulting vascular surgery (particularly if they placed your patient’s access) or interventional radiology (if access is within their purview in your shop), as well as nephrology. In our insitution, we also have outpatient vascular access clinics run by our interventional nephrologists. They can manage most of these complications on an outpatient basis.

 

References

  1. https://www.kidney.org/sites/default/files/11-50-0216_va.pdf
  2. https://www.slideshare.net/MohammedGawad/how-to-examine-avf-in-10-minutes
  3. Shi, S. H., & Chen, T. J. (2018). A Reliable Method: Purse-String Hemostasis for Arteriovenous Fistula or Arteriovenous Graft Cannulation after Percutaneous Transluminal Angioplasty. Acta Cardiologica Sinica, 34(6), 526–529. doi:10.6515/ACS.201811_34(6).20180622A
  4. https://emblog.mayo.edu/2015/04/27/how-to-stop-a-post-dialysis-site-bleeding/
  5. https://www.acepnow.com/article/dialysis-access-emergencies/?singlepage=1&theme=print-friendly
  6. http://www.emdocs.net/dialysis-patient-managing-fistula-complications-emergency-department/
  7. http://www.vascularaccessdoc.com/pdf/22.pdf
  8. Tintinalli, J. E., Stapczynski, J. S., Ma, O. J., Yealy, D. M., Meckler, G. D., & Cline, D. (2016). Tintinalli’s emergency medicine: A comprehensive study guide (Eighth edition.). New York: McGraw-Hill Education.
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T3

EM/IM '22 with interests in critical care and education. Loves travel, cats, and spending time with her co-residents!

T3

EM/IM ’22 with interests in critical care and education. Loves travel, cats, and spending time with her co-residents!

1 Comment

Tedward · July 24, 2019 at 12:00 pm

Strong work Taylor!! This is an awesome post on a really important and practical topic. Great description and pictures!

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