Vascular Access in Hemodialysis
Guideline Recommendations
- The Kidney Disease Outcomes Quality Initiative (KDOQI) guidelines recommend a "Patient Life-Plan" approach for vascular access selection, considering patient life expectancy, comorbidities, and vessel characteristics to optimize access selection and reduce complications 1
- The KDOQI guidelines recommend arteriovenous fistulas (AVFs) as the gold standard, with the lowest infection rates and best long-term patency, but acknowledge that arteriovenous grafts (AVGs) are appropriate when AVF creation is not feasible or urgent dialysis is needed 1
- The KDOQI guidelines recommend limiting central venous catheters to short-term use, specific medical circumstances, or less than 10% of chronic maintenance hemodialysis patients, due to higher mortality and infection risks 2
Access Monitoring and Maintenance
- The American Journal of Kidney Diseases recommends target thrombosis rates of <0.25 episodes/patient-year for AVFs and <0.5 episodes/patient-year for AVGs, and suggests improved ultrasound surveillance techniques to detect stenosis before thrombosis 2
- The Journal of the American College of Radiology recommends endovascular interventions as first-line treatment for access dysfunction, to improve long-term patency and reduce complications 3
Access Planning and Selection
- The KDOQI guidelines recommend access planning that includes contingency plans, succession planning, and consideration of patient-specific factors like age, comorbidities, and vessel quality, to optimize access selection and reduce complications 1
- Hemodialysis requires high blood flow rates of at least 300-350 mL/min, which can be achieved through AVFs, AVGs, or central venous catheters, with AVFs considered the gold standard due to lowest infection rates (1-4%) and best long-term patency (4-5 year survival) 4, 5, 1, 2, 3
- The type of vascular access significantly impacts dialysis adequacy and patient survival, with AVFs supporting higher blood flow rates and lower mortality risk compared to AVGs and central venous catheters, as shown in the following table:
| Access Type | Infection Rate | Patency Rate | Mortality Risk |
|---|---|---|---|
| AVF | 1-4% | 4-5 year survival | 1.0 (reference) |
| AVG | 11-20% | 3-7 times more access events than AVFs | 1.47 times greater than AVF |
| Central Venous Catheter | highest infection rates | inadequate blood flow rates | 2.3 times greater than AVF |
- Delayed referral for vascular access creation often results in catheter dependence and poorer outcomes, highlighting the importance of timely referral and access monitoring to detect access dysfunction early and prevent thrombosis and access loss 4, 2
- The KDOQI guidelines recommend evaluating patients for AVF feasibility by assessing vessel adequacy with ultrasound mapping, considering patient's life expectancy and comorbidities, and evaluating urgency of dialysis need, with early referral to nephrology increasing the probability of successful AVF creation 1, 2, 3