Residency · Residency · Vascular Surgery

Dialysis Access Planning: Fistula First and the KDOQI Guidelines

Overview

Hemodialysis access serves as a critical lifeline for patients with end-stage renal disease (ESRD). In the United States, over 550,000 individuals rely on hemodialysis, and complications related to vascular access remain a leading cause of hospitalization in this population. There are three primary types of hemodialysis access: arteriovenous fistula (AVF), arteriovenous graft (AVG), and central venous catheter (CVC). The Kidney Disease Outcomes Quality Initiative (KDOQI) guidelines emphasize the use of autogenous fistulas as the preferred access type due to their superior long-term outcomes. However, there is growing recognition of the need for individualized access planning tailored to each patient’s unique clinical circumstances.

KDOQI Guidelines and Fistula First Initiative

Key KDOQI Recommendations

The KDOQI guidelines recommend referral to a vascular surgeon when the patient’s glomerular filtration rate (GFR) falls below 25 mL/min or when dialysis is anticipated within one year. The preferred order of access creation is an autogenous AVF first, followed by a prosthetic AVG, and finally a CVC as the last resort. AVFs should ideally be placed at least six months before the anticipated start of dialysis to allow for adequate maturation, while AVGs require a shorter incorporation period of three to six weeks before use. CVCs should be minimized due to their high risk of infection and central venous stenosis. The target set by KDOQI is that at least 65% of prevalent hemodialysis patients use AVFs.

Fistula First Breakthrough Initiative (FFBI)

Launched in 2003, the Fistula First Breakthrough Initiative was a national quality improvement program aimed at increasing AVF use and reducing reliance on CVCs. This initiative successfully raised AVF prevalence from approximately 30% to over 65%. However, it faced criticism for promoting a "Fistula First at all costs" approach, which sometimes led to multiple failed access attempts, prolonged dependence on CVCs, and increased patient morbidity, particularly in patients for whom AVFs were not suitable.

Evolving Philosophy: "Right Access, Right Patient, Right Time"

The 2019 KDOQI update and the rebranding to "Fistula First Catheter Last" reflect an evolving philosophy that recognizes AVFs are not the optimal choice for every patient. This approach takes into account individual patient factors such as life expectancy, vein quality, comorbidities, and patient preferences. For patients with limited life expectancy (less than one to two years) or very poor vein quality, an AVG or even a CVC may represent the most appropriate initial access. The focus has shifted toward developing "Patient Life-Plans" rather than adhering to a rigid, algorithmic fistula-first approach.

<image>Algorithm for dialysis access planning showing patient evaluation pathway, order of access creation preference (AVF > AVG > CVC), and decision points based on vein quality, life expectancy, and comorbidities</image>

Patient Evaluation

History

A thorough history is essential in planning dialysis access. Important considerations include the stage of chronic kidney disease (CKD) and the anticipated timing of dialysis initiation. The dominant hand should be identified so that access can be placed preferentially in the non-dominant arm. Previous access attempts, catheter placements, and the presence of pacemaker or defibrillator leads must be noted, as these can impact vascular anatomy and access options. A history of central venous catheterization is particularly relevant due to the increased risk of central venous stenosis. Comorbid conditions such as peripheral vascular disease, which may impair arterial inflow, and heart failure, which can be exacerbated by high-flow fistulas, should be assessed. Additional factors include diabetes, obesity, anticoagulation use, life expectancy, and the patient’s goals of care.

Physical Examination

The physical examination focuses on the bilateral upper extremity arterial system, including palpation of radial, ulnar, and brachial pulses and comparison of blood pressures between arms. The Allen test is performed to assess the completeness of the palmar arch and collateral flow by compressing both the radial and ulnar arteries, having the patient open their hand, and then releasing one artery at a time. An incomplete palmar arch may contraindicate the use of a radial artery-based fistula due to the risk of steal syndrome. Venous examination involves inspection for visible veins and assessment of their distensibility using a tourniquet. Signs of previous access, such as scars, collateral veins, or swelling, are noted. Evaluation for central venous obstruction includes looking for arm or facial swelling and chest wall collaterals. Baseline hand perfusion is also assessed, which is important for monitoring potential steal after access creation.

Preoperative Vein Mapping

Duplex ultrasound vein mapping is the standard of care prior to access creation. This imaging assesses vein diameter, with a minimum of 2.5 mm required for AVF creation and ideally 3 mm or greater. The continuity, compressibility, and depth of veins from the skin surface are also evaluated. Arterial inflow is assessed by measuring the diameter (minimum 2.0 mm for the radial artery), waveform characteristics, and the presence of calcification. The superficial venous anatomy, including the cephalic vein throughout the arm, basilic vein, and median cubital vein, is mapped, along with identification of deep veins and perforating veins.

Central Venous Assessment

In patients with a history of central lines or symptoms suggestive of central venous stenosis, further imaging such as CT venography, MR venography, or contrast venography is indicated. Central venous stenosis, particularly involving the subclavian vein, may preclude access creation on the ipsilateral side. Assessment for superior vena cava syndrome or innominate vein occlusion is also important in this context.

Order of Access Creation

Upper Extremity (Preferred)

The preferred sequence for upper extremity access begins with the radiocephalic AVF (Brescia-Cimino fistula) at the non-dominant wrist, which offers the best long-term patency and preserves more proximal sites for future access. If this is not feasible, the brachiocephalic AVF at the antecubital fossa is the next option, providing reliable maturation and good blood flow. The brachiobasilic AVF with transposition in the upper arm is a good secondary option but typically requires a two-stage surgical procedure. When autogenous options are exhausted, prosthetic brachial-axillary or forearm loop AVGs are considered.

Lower Extremity (When Upper Extremity Exhausted)

If upper extremity sites are no longer viable, lower extremity access options include femoral vein transposition and thigh loop AVGs connecting the femoral artery to the femoral vein. These accesses carry higher risks of infection and thrombosis compared to upper extremity access.

Alternative/Unusual Access

Alternative access options include the necklace graft, which connects the axillary artery to the contralateral axillary vein, and the HeRO graft (Hemodialysis Reliable Outflow), which combines a graft component with a venous outflow component that bypasses central stenosis. Body wall access using saphenous vein or polytetrafluoroethylene (PTFE) grafts is another option in select cases.

Peritoneal Dialysis

Peritoneal dialysis should be considered as an alternative modality, especially for patients with limited vascular access options, as it preserves vascular sites and can be suitable for many individuals.

<image>Diagram showing the order of preferred dialysis access sites from distal to proximal: radiocephalic fistula at the wrist, brachiocephalic fistula at the elbow, brachiobasilic transposition in the upper arm, and prosthetic graft configurations</image>

Vein Preservation

Vein preservation is critical and should begin early in CKD stages 3 to 4. Potential fistula veins must be protected by avoiding venipuncture, intravenous lines, and peripherally inserted central catheters (PICCs) in the non-dominant arm. Subclavian central lines should be avoided due to their high risk of causing subclavian vein stenosis; internal jugular vein access is preferred. Patients should be educated to wear medical alert identification indicating the need for vein preservation. The KDOQI guidelines recommend wearing an alert bracelet with instructions such as "No needles, no blood pressure, no tourniquets" on the designated arm.

Special Populations

Elderly Patients

Elderly patients experience higher rates of fistula failure to mature, with failure rates reaching 50-60%. They may benefit from initial AVG placement, which offers more predictable maturation and earlier cannulation. When life expectancy is less than one to two years, a catheter may be a reasonable option. Shared decision-making is essential to balance risks and benefits in this population.

Diabetic Patients

Diabetic patients often have calcified, non-compliant arteries and poor vein quality, increasing the risk of steal syndrome due to concurrent peripheral arterial disease. They may require upper arm rather than forearm access and are more likely to need an AVG because of poor vein quality.

Obese Patients

In obese patients, veins may lie too deep for superficial cannulation despite adequate diameter. Brachiobasilic transposition or superficialization procedures are often necessary. Lipectomy at the access site can facilitate cannulation, and ultrasound-guided cannulation should be considered to improve success.

Pediatric Patients

Peritoneal dialysis is generally preferred as the initial modality in pediatric patients. If hemodialysis is required, AVF creation follows similar principles but requires technical modifications due to smaller vessel size. Central venous catheters are often necessary initially in this group.

Heart Failure Patients

High-flow AVFs can exacerbate cardiac output burden in patients with heart failure. Flow-limiting strategies such as Revision Using Distal Inflow (RUDI) or banding may be employed. Consultation with cardiology is important to determine optimal access flow rates. AVGs, which typically have more predictable and lower flow, may be preferable in these patients.

<image>Preoperative duplex ultrasound vein mapping images showing measurement of cephalic vein diameter, depth from skin surface, and assessment of vein compressibility and continuity along the upper extremity</image>

Timing of Access Placement

AVFs should be placed at least six months before the anticipated start of dialysis to allow for adequate maturation. AVGs require placement three to six weeks prior to dialysis, although early cannulation grafts can be used within 24 to 72 hours. CVCs can be used immediately but carry the highest rates of complications. Late referral to vascular surgery remains a significant problem, resulting in many patients initiating dialysis with catheters. Patients who start dialysis unplanned, often called "crash starters," have the highest rates of CVC use and the worst outcomes.

Emerging Concepts

Endovascular AVF Creation

Endovascular AVF creation involves percutaneous formation of an arteriovenous fistula using thermal (Ellipsys) or radiofrequency (WavelinQ) devices. These techniques create a fistula between adjacent deep arteries and veins, typically the radial artery and a perforating vein. Advantages include the absence of a surgical incision and the ability for nephrologists or interventionalists to perform the procedure. Although maturation rates are improving, these methods remain under investigation. The NEAT and EASE trials demonstrated the feasibility and reasonable maturation rates of endovascular AVFs.

Early Cannulation Grafts

Early cannulation grafts are PTFE grafts with modified architecture that allow cannulation within 24 to 72 hours of placement. Examples include Acuseal and Flixene grafts. These grafts serve as a bridge for patients who require urgent dialysis initiation without the use of a CVC.

Bioengineered Grafts

Bioengineered grafts, such as the human acellular vessel (Humacyte), represent a novel vascular conduit that avoids immune rejection and may have lower infection rates. The FDA Biologics License Application for these grafts is currently under review. They hold promise for patients with limited autogenous access options.

Clinical Pearls

The optimal dialysis access is one that functions well, matures appropriately, and endures over time; it is not necessarily an AVF in every patient. Planning for access should begin when the GFR approaches 25 mL/min, as early referral helps prevent catheter dependence. Duplex vein mapping must always be performed before access creation, since blind surgical exploration is associated with higher failure rates. Subclavian vein catheterization should be avoided in any patient who may require hemodialysis access, with internal jugular vein access preferred to prevent subclavian stenosis that can compromise the entire ipsilateral arm. A two-stage brachiobasilic transposition is generally preferred over a single-stage procedure due to better maturation and patency rates. A patient’s fistula potential should not be abandoned after a single failed attempt; referral to a high-volume access surgeon can reveal alternative options. In elderly patients with poor veins, an AVG may be a better choice than multiple failed AVF attempts that prolong catheter dependence.

References

• Lok CE, et al. KDOQI clinical practice guideline for vascular access: 2019 update. Am J Kidney Dis. 2020;75(4 Suppl 2):S1-S164.
• Robbin ML, et al. Hemodialysis arteriovenous fistula maturity: US evaluation. Radiology. 2002;225(1):59-64.
• Al-Jaishi AA, et al. Patency rates of the arteriovenous fistula for hemodialysis: a systematic review and meta-analysis. Am J Kidney Dis. 2014;63(3):464-478.
• Hull JE, et al. (NEAT trial) Endovascular creation of an arteriovenous fistula for hemodialysis access. J Vasc Interv Radiol. 2018;29(2):233-238.
• Bylsma LC, et al. Association of hemodialysis vascular access type with clinical indicators and patient outcomes. J Am Soc Nephrol. 2021;32(2):535-545.

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