Complications of hemodialysis (HD) access create significant problems for renal practitioners, the healthcare system and especially for individuals living with end stage renal disease. Chronic HD access complications include thrombosis, infection, ischemic steal syndrome, aneurysms, venous hypertension, hematomas, heart failure, and prolonged bleeding and result in frequent interventions and increased morbidity and mortality¹. In addition, access interventions are often costly, challenging and may require specialized surgical expertise.

Thrombosis and infection are the among the most common vascular access dysfunctions¹ and thrombosis is the most common cause of vascular access loss². Thrombosis and infection occur more frequently in arteriovenous grafts (AVG) and dialysis catheters than in arteriovenous fistulae (AVF). The Dialysis Outcomes and Practice Patterns Study (DOPPS) reports that AVG are 3.8 times more likely to require thrombectomy and 3.0 times more likely to require access intervention than AVF³. AVF thrombosis rates remain in the range of 0.2 to 0.8 per patient year and AVG thrombosis rates are typically in the range of 0.6 to 1.2 per patient year⁴.  Although, the United States Renal Data System (USRDS) data confirm that AVF have the lowest complication rates of any available vascular access with 0.64 procedures per patient year versus 1.61 for AVG⁵; once a primary fistula is established, thrombosis is the leading cause of failure in approximately 40% of cases⁶.

Infectious complications of vascular access are a major source of morbidity and mortality among HD patients. Previous studies have reported infection as a common cause of death; accounting for 9.5 to 36% of deaths in HD patients⁷. Vascular access infections (most commonly found in patients utilizing dialysis catheters) are reported to be the source in up to 48 to 73% of all bacteremias in HD patients⁸. The risk of bacteremia with tunnel cuffed catheters averages 2.3 per 1000 catheter days.  This translates into an approximate 20 to 25% bacteremia risk over the average duration of use¹.

Ischemic steal syndrome secondary to a HD arteriovenous access occurs in approximately 5 to 10% of cases⁹. The pathophysiological basis of this condition is a marked decrease or reversal of flow in the arterial segment distal to the AVF or AVG, induced by the low resistance of the fistula outflow^9. Mild cases can be observed closely, as most of them will reverse in a few weeks; however, severe cases require immediate intervention to prevent severe ischemic complications including ischemic neuropathy and ischemic gangrene with the potential need for amputation. Several surgical and endovascular treatments have been used including: access ligation, banding, elongation, distal arterial ligation, and distal revascularization-interval ligation. The best reported results, for treatment of dialysis access-associated steal syndrome with maintenance of access function and reversal of symptoms, have been obtained with the distal revascularization-interval ligation (DRIL) ⁹ and the endoluminal-assisted revision (MILLER) procedures¹⁰.

Aneurysms and pseudoaneurysms, resulting from improper needle site rotation or as complications of more proximal stenosis, are less frequent complications of vascular access. AVG peudoaneurysms can develop profuse bleeding and require emergency surgical intervention.  Appropriate selection of dialysis staff for access cannulation together with cannulation training and education for staff members and patients may reduce the risk of this complication.  In addition, visibly tortuous access shape is a major cosmetic concern for many patients.

Venous hypertension occurs in approximately 3% of fistulas and grafts and is usually related to central vein stenosis (CVS)¹. Percutaneous transluminal angioplasty of a CVS, supplemented by stent placement as needed, is effective and considered the primary treatment for such lesions due to the lack of viable and safe surgical options¹¹.

Hematomas result from needle infiltration. Needle infiltration of new fistulae is a relatively frequent complication, which occurs most commonly in older patients¹⁴. If the access has been assessed as mature for venipuncture, poor cannulation skills are often the root cause of infiltrations.

High-output heart failure from fistula placement occurs if fistula flow exceeds 20% of cardiac output¹². This complication is a rare complication that is usually under-diagnosed in the dialysis population¹³.

Prolonged access bleeding should not be overlooked, and should raise suspicion of high intra-access pressure, outflow stenosis or local inflammation. Prolonged bleeding may also be caused by excessive heparinization of the blood circuit, access laceration during previous cannulation or skin atrophy¹⁵. Clinical examination of the site should be performed, and previous static or dynamic venous pressure measurements should be reviewed.

Vascular access management has improved dramatically over the past decades⁴.  Promising new therapies including catheter lock solutions, biological tissue engineering and the merging of current access conduits into a singular device are currently under development and evaluation. It is hoped that these and other new technologies may decrease the future incidence of vascular access complications.

References

1. Stolic R. Most important chronic complications of arteriovenous fistulas for hemodialysis. Med Princ Pract. 2013;22(3):220-228. Available from: /pmc/articles/PMC5586732/.
2. Quencer KB, Oklu R. Hemodialysis access thrombosis. Cardiovasc Diagn Ther. 2017;7(Suppl 3):S299-S308. Available from: /pmc/articles/PMC5778528/.
3. Young EW, Dykstra DM, Goodkin DA, Mapes DL, Wolfe RA, Held PJ. Hemodialysis vascular access preferences and outcomes in the Dialysis Outcomes and Practice Patterns Study (DOPPS). Kidney Int. 2002;61(6):2266-2271. Available from: http://www.ncbi.nlm.nih.gov/pubmed/12028469.
4. Sands JJ. Vascular access 2007. Minerva Urol Nefrol. 2007;59(3):237-249. Available from: http://www.ncbi.nlm.nih.gov/pubmed/17912221.
5. United States Renal Data System. 2019 USRDS Annual Data Report: Epidemiology of kidney disease in the United States. National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases, Bethesda, MD, 2019. Available from: https://www.usrds.org/annual-data-report/.
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8. Nassar GM, Ayus JC. Infectious complications of the hemodialysis access. Kidney Int. 2001;60(1):1-13. Available from: http://www.ncbi.nlm.nih.gov/pubmed/11422731.
9. Schanzer H, Eisenberg D. Management of steal syndrome resulting from dialysis access. Semin Vasc Surg. 2004;17(1):45-49. Available from: http://www.ncbi.nlm.nih.gov/pubmed/15011179.
10. Goel N, Miller GA, Jotwani MC, Licht J, Schur I, Arnold WP. Minimally Invasive Limited Ligation Endoluminal-assisted Revision (MILLER) for treatment of dialysis access-associated steal syndrome. Kidney Int. 2006;70(4):765-770. Available from: http://www.ncbi.nlm.nih.gov/pubmed/16816841.
11. Levit RD, Cohen RM, Kwak A, et al. Asymptomatic Central Venous Stenosis in Hemodialysis Patients. Radiology. 2006;238(3):1051-1056. Available from: http://www.ncbi.nlm.nih.gov/pubmed/16424248.
12. Saleh MA, El Kilany WM, Keddis VW, El Said TW. Effect of high flow arteriovenous fistula on cardiac function in hemodialysis patients. Egypt Hear J. 2018;70(4):337-341. Available from: /pmc/articles/PMC6303531/.
13. Khreiss M, Haddad FF, Musallam KM, Medawar W, Daouk M, Khalil I. High-output cardiac failure secondary to a large arteriovenous fistula: A persistent threat to the dialysis and kidney transplant patient. NDT Plus. 2009;2(2):147-148. Available from: /pmc/articles/PMC4421340/.

P/N 101051-01 Rev A 03/2021