Section 1: Introduction  

The treatment option for Renal Replacement Therapy (RRT) is determined by patient factors, the dialysis access team skills and knowledge, geographic policies and resources, to mention a few. A successful outcome is associated with continuous short and long-term planning and the appropriate access RRT is always chosen for each patient (Reference 1). Therefore, no mode of dialysis or type and site of dialysis access can be considered superior, mandatory, or labeled ‘gold standard’. For example, peritoneal dialysis and hemodialysis must not be looked upon as competitive forms but rather complementary as several dialysis access types and devices may be used over a patient’s lifetime, including renal transplantation (Table 1). There is much regional variation in how ESRD treatment is applied, and no universal rules exist. Of the five options listed below in Table 1, the healthcare provider ultimately relies on professional judgment and a mission statement oriented to patient-centered care.

Table 1. The Five Basic Renal Replacement Therapy (RRT) Options for ESRD

  1. Renal transplant
  2. Hemodialysis
  3. Peritoneal dialysis
  4. Medical treatment only
  5. Hospice

A functioning kidney—native or transplanted—is the most effective replacement for a dialysis machine. Hemodialysis is the dominant selected treatment worldwide. Peritoneal dialysis varies from being unavailable in some regions to accounting for 70% of initiations in Hong Kong by government mandate. Many well informed patients choose medical treatment only, while the hospice option is similar to any individual with imminent mortality.

This chapter outlines basic principles for native-vein AVF. The radio-cephalic wrist anastomosis is described in detail because the surgical techniques are similar across sites. Adherence to atraumatic vascular technique is paramount, as these patients are at high risk due to uremia, renal failure, and associated comorbidities. Failure of an AVF is usually not limb-threatening (unlike other vascular procedures), but the implications are far-reaching particularly for younger patients adjusting to a lifetime of chronic disease. Also, techniques are covered in detail with 19 short videos illustrating steps for an upper arm basilic vein transposition procedure (x-x).

Recent endovascular innovations have introduced two minimally invasive approaches to create AVFs using one- or two-catheter systems. Using similar endovascular methods, the modified Seldinger peritoneal dialysis catheter placement is likewise a minimally invasive dialysis access (MIDA) procedure. Preliminary reports claim near 100% technical success and maturation rates in the 80–90% range. This evolving technology may expand dialysis options for very ill patients because general anesthesia is not required. Its role in dialysis access will be clarified over the next few years (7)

The native-vein options for dialysis vascular access are determined by patient factors; access team skills and knowledge; and institutional and geographic policies and resources (Table 2). Successful outcomes depend on continuous short- and long-term planning with individualized selection. Accordingly, no dialysis mode or access site should be labeled a “gold standard.” Peritoneal dialysis and hemodialysis are complementary, and all RRTs—including renal transplantation—may be used over a patient’s lifetime. Likewise, native-vein AVFs and grafts are indicated for different patient cohorts according to national and local algorithms. This chapter details the use of native veins for dialysis vascular access.

Table 2.  Types of Arteriovenous Fistulae (AVF) Procedures.

  1. Radio-Cephalic AVF at the wrist (RC AVF) (Figure 1)
  2. Ulnar-Basilic
  3. Radio-Basilic
  4. Brachio-Cephalic (Figure 2)
  5. Proximal Radial Artery to Median Cubital Vein
  6. Basilic Vein Transposition in the forearm
  7. Basilic Vein Transposition in the upper arm (Figure 3)
  8. Cephalic vein Transposition or superficialization for obesity
  9. Saphenous vein Transposition Groin
  10. Vein translocations
  11. Human genetically engineered conduct (currently) in clinical studies)

The Three Most Common Types of AVFs are Bolded in table 2 and pictured in (Figure 1, Figure 2. and Figure 3).

  1. Radial-Cephalic fistula, (RC AVF) (Figure 1) is the most common native vein AVF and is described in detailed images below. The surgery is generally accomplished by an end vein to side artery anastomosis. The wrist radio-cephalic fistula was first performed by Kenneth Appel, a New York surgeon in 1965. The anastomosis was side to side between the radial artery and the cephalic vein and a 3–5 mm anastomosis using silk sutures in a continuous fashion. Anecdotally, the outcomes of this historic small series were impressive with a primary patency of 12/14 (86%). This classic Brescia-Cimino AVF used a side vein to side artery anastomosis, which often led to venous hypertension in the hand from incompetent valves in the cephalic vein distal to the anastomosis. The distal radial artery used as inflow results in lower blood flow than the brachial artery based AVF. When Radio-cephalic (RC) AVF is used as the first hemodialysis HD), the upper arm vessels are enlarged over time from high blood flow and must be preserved for later use if needed. This is referred to as “secondary fistula” as the outflow vein upper arm cephalic or the basilic veins are dilated from this forearm AVF. We will describe the principal detailed techniques for making the RC AVF anastomosis (Figures 6-31). Most technical steps can be generally applied for other AVF anastomoses sites. 
  2. The Brachial-Cephalic fistula (BC AVF) (Figure 2) requires less dissection than a brachio-basilic transposition (BVT) (Figure 3) where the entire vein needs to be mobilized and transposed closer to the skin. The distal brachial artery upper arm AVFs have a higher blood flow than the RC AVF, and a higher incidence of steal syndrome between 5-10%. (Reference 1). The proximal radial artery at the elbow is sometimes used for anastomosis rather than the brachial artery in cases of upper arm cephalic vein, although, this is generally still referred to as a brachial-cephalic (BC) AVF).  Compared to distal brachial artery proximal radial has less risk of development of Dialysis Access Steal Syndrome (DASS)
  1. Brachial-Basilic AVF (Figure 3) involves variations of basilic vein transposition (BVT) or superficialization. The BVT procedure requires more surgical skills because of its complex and variable anatomy adjacent to upper arm vital structures such as the brachial artery, the median nerve and the medial brachial sensory nerve and the median cutaneous nerve of the forearm. (Video links 1-19).

The vein must be both elevated (superficialized) and transposed to a more lateral position to enable repeated cannulations. Since the basilic vein is less accessible for veno punctures it is usually well preserved except for the increasing use of peripherally inserted central catheter (PICC) lines. When the proximal radial artery is used for anastomosis in upper arm fistulae the risk of distal ischemia is decreased.

Order of Preference in Fistula Creation. Various societies guidelines suggest the order of AVF preference with the rationale of ease of construction and less patient morbidity are depicted in Table 2.  One such rule is to start distally to preserve more proximal veins for future use. It is our opinion that individual patient factors and circumstances must take precedence over simplistic intuitive guidelines. The access choice must be adapted to each patient and circumstances at the time of presentation and based on the dialysis access mission statement of doing the right thing, to each patient at the right time in the right amount guided by society laws where you live (Reference 2).

For discussions of dialysis access algorithms, the reader is referred to: Chapter 2 in www.kidneyacademy.com, Renal Replacement Therapy Algorithms.

Table 2. The suggested or preferred order of preference for AVF    

  1. Radial-Cephalic AVF (Figure 1)
  2. Brachio-cephalic AVF (Figure 2)
  3. Basilic vein Transposition AVF (Figure 3) and (Reference 3)

Fistula Maturation. There is no uniform definition for AVF maturation except successful repeat cannulations.  First, it must have adequate blood flow of 600 ml/min to support dialysis and second, it should be of adequate diameter of 6 mm diameter to allow for needle size between 14-16 g. Characteristics of usable fistula requirements for successful cannulation is popularized as the “Rule of 6” that considers blood flow, fistula vein diameter, depth, and cannulation segment length assessed at 6 weeks after creation (Table 3).

 

TABLE 3. The “RULE of 6s”

  1. The AVF within 6 mm below the skin surface for reliably cannulation
  2. At least 6 inches (10-15 cm) of vein length available for cannulation
  3. Blood flow of 600 ml/min, in the artery proximal to the anastomosis
  4. A fistula vein inner diameter of at least 6 mm

 

Blood flow adequate to support dialysis varies with location practices. To be used as dialysis access, the AVF must be able to sustain the blood of about 500-600 mL/min is the minimum required for adequate dialysis. This is related to body size and the duration of each dialysis treatment. With longer dialysis treatment times of 4-6 hours practiced in some countries, a fistula flow of 250-300 ml/min may suffice. (Document 3).

Size Adequate to Permit Repetitive Cannulation for successful long-term dialysis, the AVF must have an inner diameter that will permit repetitive cannulation. To do this, the staff must be able to see or at least feel the vein.  The consensus is a minimum cannulation diameter of 5-6 mm.

Fistula Vein Depth under skin surface presents two problems. First, the standard dialysis needle is only 1¼ inch (3.2 cm) in length. Second, access vein needs to be palpable by the cannulating individual. Various surgical methods have been used to make the vein more superficial, including liposuction. Perhaps the most important factor is selection of an access vein that is less than 6 mm under the skin surface and with a cannulation length of at least 10 – 15 cm or 6 inches. Other dialysis options such as peritoneal dialysis must be considered in a structured analysis approach to ESRD treatment options (ref).

Segment for Cannulation must have a relatively straight segment available for repeated two needles. At a minimum, this should be 10 – 15 cm in length. This length is necessary because cannulation sites must be rotated to preserve the AVF long-term repeat cannulations. This requires space, as the dialysis needle must be inserted a short distance inside the vein to be stable during the dialysis session. Attempts at cannulation into a tortuous AVF are often met with disaster. Unfortunately, a straight segment is not always present. In these cases, it may be possible to straighten the vein by surgical intervention.

Time to Maturation. The percentage of fistula that matures and the time it takes is quite variable. AVFs that will mature do so within 4-6 weeks.  There are several less controlled factors that delay fistula cannulation. (Figure 4) Common potential hurdles to access maturation include a delay of about 1 month from being referred between specialties such as surgical evaluation. Second, there is a delay of up to 4 months for scheduling surgery. Finally, another 7 months delay ensues before the fistula matures, that is being used for dialysis. It should be noted that about 30-50% of AVFs are never used.

The image (Figure 4) illustrates flagrant examples of common systems lacking structured planning for optimal outcome.

Figure 4

This image depicts common hurdles to access maturation. First, there is often a delay of about 1 month from being referred (red line) to being seen (blue line) for surgical evaluation. Second, there is a delay of about 4 months for surgical scheduling (the green line) for AVF surgery. Finally, there is another 7 months delay before the fistula matures, that is being used for dialysis (bottom light blue line). It should be noted that about 30 – 50 % of AVFs have primary failure and therefore never mature or used

Figure 4

System designs such as referral patterns, institutional, regional and country policies, culture and “intuitions” are influential forces for ESRD treatment options and outcomes. The image (Figure 4) is an example of a system lacking structured planning for optimal outcome (1).

Nephrology Referral patterns greatly affect outcomes including sepsis from prolonged use of central vein catheters (1-4). Planning is key to changing these adverse outcomes.  Patients who see a nephrologist prior to the need for dialysis start dialysis more often with AVF as a permanent access (2,3,5).

Optimal time for Access placement timing is complex partly because of the unpredictable decline in renal function. As a rough guide creatinine clearance of 15–20 ml ⁄ minute or serum creatinine of 3.4–5.6 mg⁄ dl, stage 4 of Chronic Kidney Disease (CKD) and the size and weight of the patient should initiate referring to the nephrologist or surgeon for vascular access when they reach (glomerular filtration rate <30 ml/min/1.73 m2) or earlier in case of rapidly progressive nephropathy or specific clinical and local facilities. This concept was included in the 2019 update of KDOQI guidelines (7).

To improve the planning and timing of access placement the Kidney Failure Risk Index (KFRI) may be used. Although not validated in this setting, the KFRI gives a time prediction of reaching end stage renal disease within 2 and 5 years. KFRI is age, GFR and proteinuria dependent (7-13).

Atraumatic surgical technique is of paramount importance in dialysis access as patients are often elderly and with comorbidities. The recent innovations with percutaneous peritoneal dialysis catheters using strict catheter technique and the percutaneous AVF techniques have made placement less traumatic and expanding indications to the very ill patients and being performed with ultrasound and fluoroscopic guidance under local anesthesia.   These techniques require technical skills and team cooperation. The real-world outcome remains uncertain. The cost of devices and added procedures required for maturation and patency may prevent widespread application.  These techniques are summarized in Document 6. 

  1. Lee, T, Barker, J, Allon, M. Tunneled catheters in hemodialysis patients: reasons and subsequent outcomes. Am J Kidney Dis 2005; 46:501
  2. Astor, BC, Eustace, JA, Powe, NR, et al. Timing of nephrologist referral and arteriovenous access use: the CHOICE Study. Am J Kidney Dis 2001; 38:494.
  3. Lee, T, Barker, J, Allon, M. Associations with pre-dialysis vascular access management. Am J Kidney Dis 2004; 43:1008.
  4. Lee, T, Barker, J, Allon, M. Tunneled catheters in hemodialysis patients: reasons and subsequent outcomes. Am J Kidney Dis 2005; 46:501
  5. Astor, BC, Eustace, JA, Powe, NR, et al. Timing of nephrologist referral and arteriovenous access use: the CHOICE Study. Am J Kidney Dis 2001; 38:494.
  6. Lee, T, Barker, J, Allon, M. Associations with pre-dialysis vascular access management. Am J Kidney Dis 2004; 43:1008
  7. NKF-K/DOQI Clinical Practice Guidelines for Vascular Access: Update 2006. Guideline 1: Patient preparation for permanent hemodialysis access.
  8. Jindal, K, Chan, CT, Deziel, C, et al. Hemodialysis clinical practice guidelines for the Canadian Society of Nephrology. J Am Soc Nephrol 2006; 17: S1.
  9. Tangri, N, Stevens, LA, Griffith, J, et al. A predictive model for progression of chronic kidney disease to kidney failure. JAMA 2011; 305:1553.
  10. Tangri, N, Grams, ME, Levey, AS, et al. Multinational Assessment of Accuracy of Equations for Predicting Risk of Kidney Failure: A Meta-analysis. JAMA 2016; 315:164.
  11. Cravedi, P, Remuzzi, G. Pathophysiology of proteinuria and its value as an outcome measure in chronic kidney disease. Br J Clin Pharmacol 2013; 76:516.
  12. Levey, AS, Cattran, D, Friedman, A, et al. Proteinuria as a surrogate outcome in CKD: report of a scientific workshop sponsored by the National Kidney Foundation and the US Food and Drug Administration. Am J Kidney Dis 2009; 54:205.
  13. Nitsch, D, Grams, M, Sang, Y, et al. Associations of estimated glomerular filtration rate and albuminuria with mortality and renal failure by sex: a meta-analysis. BMJ 2013; 346: f324
  14. Peeters, MJ, van Zuilen, AD, van den Brand, JA, et al. Validation of the kidney failure risk equation in European CKD patients. Nephrol Dial Transplant 2013; 28:1773.
  15. Hingwala, J, Wojciechowski, P, Hiebert, B, et al. Risk-Based Triage for Nephrology Referrals Using the Kidney Failure Risk Equation. Can J Kidney Health Dis 2017; 4:2054358117722782.
  16. Hiremath, S, Knoll, G, Weinstein, MC. Should the arteriovenous fistula be created before starting dialysis? A decision analytic approach. PLoS One 2011; 6: e28453. 

Patient Evaluation Prior To Access Placement in preparation is extremely important. Proper patient selection will materially enhance the opportunity to place an AVF. This evaluation must be detailed and complete. This is covered in depth in Chapter 2 of www.kidneyacademy.com

TABLE 4.   Principles of good practice for saving the veins for AVF  

  • Wear a Save the Vein wristband to alert health care providers
  • Use the dorsum of hands first for vein access
  • After starting dialysis, use wristband to protect access
  • Inform health care providers of vein preservation.

For in-depth physical examination in dialysis access the reader is referred to: www.kidneyacademy.com planned for Febr 2026

 

Table 5. Anatomical Requirements for a Fistula vary widely between institutions, affecting the AVF maturation process

Artery Requirements

  • A feeding artery with unobstructed flow
  • Patent palmar arch(es)
  • Luminal inner diameter 5 mm or greater at anastomosis site

Vein Requirements

  • Luminal inner diameter 4-5 mm or greater at anastomosis point
  • Absence of obstruction/stenosis on preop ultrasound mapping
  • Straight segment for cannulation of 10 – 15 cm
  • Within 6 mm below skin surface
  • Continuity with proximal (central) veins

Various authors advocate different sizes of veins and artery suitable for AVF formation. While technically the anastomosis of vessels smaller than those stated in Table 6 can be performed, the maturation of such fistulas is unpredictable and often poor. Technical vascular surgical challenges do not always translate into good patient outcomes.

For a fistula to mature requires suitable inflow, a suitable vein conduit and unrestricted low resistance outflow. The blood flow increase through the inflow artery is rapid and within 24 hours the brachial artery flow increases 10-fold from normal 40 – 50 ml/min to almost 400 ml/min and up to 20 times after 8-9 months (Figure 5). (14-17) 

Figure 5

Blood volume flow changes over time after surgical placement of an AVF. The blood flow increase is over 500% in the first 24 hours after placement and reaches a flow of at least 500 ml/min after one month. (Courtesy Dr G. Beathard)

Figure 5

Section 1: Introduction  

The option for Renal Replacement Therapy (RRT) is determined by patient factors, the dialysis access team skills and knowledge, geographic policies and resources, to mention a few. A successful outcome is associated with continuous short and long-term planning and the appropriate access RRT is always chosen for each patient (Reference 1). Therefore, no mode of dialysis or type and site of dialysis access can be considered superior, mandatory, or labeled ‘gold standard’. For example, peritoneal dialysis and hemodialysis must not be looked upon as competitive forms but rather complementary as several dialysis access types and devices may be used over a patient’s lifetime, including renal transplantation (Table 1). There is much regional variation in how ESRD treatment is applied, and no universal rules exist. Of the five options listed below in Table 1, the healthcare provider ultimately relies on professional judgment and a mission statement oriented to patient-centered care.  

Table 1. The Five Basic Renal Replacement Therapy (RRT) Options for ESRD

  1. Renal transplant
  2. Hemodialysis
  3. Peritoneal dialysis
  4. Medical treatment only
  5. Hospice

A functioning kidney—native or transplanted—is the best replacement for a dialysis machine. Hemodialysis is the dominant selected treatment worldwide. Peritoneal dialysis varies from being unavailable in some regions to accounting for 70% of initiations in Hong Kong by government mandate. Many well informed patients choose medical treatment only, while the hospice option is similar to any individual with imminent mortality.

This chapter outlines basic principles for native-vein AVF. The radio-cephalic wrist anastomosis is described in detail because the surgical techniques are similar across sites. Adherence to atraumatic vascular technique is paramount, as these patients are at high risk due to uremia, renal failure, and associated comorbidities. Failure of an AVF is usually not limb-threatening (unlike other vascular procedures), but the implications are far-reaching particularly for younger patients adjusting to a lifetime of chronic disease. Also, techniques are covered in detail with 19 short videos illustrating steps for an upper arm basilic vein transposition procedure (x-x).

Recent endovascular innovations have introduced two minimally invasive approaches to create AVFs using one- or two-catheter systems. Using similar endovascular methods, the modified Seldinger peritoneal dialysis catheter placement is likewise a minimally invasive dialysis access (MIDA) procedure. Preliminary reports claim near 100% technical success and maturation rates in the 80–90% range. This evolving technology may expand dialysis options for very ill patients because general anesthesia is not required. Its role in dialysis access will be clarified over the next few years (7).

The native-vein options for dialysis vascular access are determined by patient factors; access team skills and knowledge; and institutional and geographic policies and resources (Table 2). Successful outcomes depend on continuous short- and long-term planning with individualized selection. Accordingly, no dialysis mode or access site should be labeled a “gold standard.” Peritoneal dialysis and hemodialysis are complementary, and all RRTs—including renal transplantation—may be used over a patient’s lifetime. Likewise, native-vein AVFs and grafts are indicated for different patient cohorts according to national and local algorithms. This chapter details the use of native veins for dialysis vascular access.

Table 2.  Types of Arteriovenous Fistulae (AVF) Procedures.

  1. Radio-Cephalic AVF at the wrist (RC AVF) (Figure 1)
  2. Ulnar-Basilic
  3. Radio-Basilic
  4. Brachio-Cephalic (Figure 2)
  5. Proximal Radial Artery to Median Cubital Vein
  6. Basilic Vein Transposition in the forearm
  7. Basilic Vein Transposition in the upper arm (Figure 3)
  8. Cephalic vein Transposition or superficialization for obesity
  9. Saphenous vein Transposition Groin
  10. Vein translocations
  11. Human genetically engineered conduct (currently) in clinical studies)

The Three Most Common Types of AVFs are Bolded in table 2 and pictured in (Figure 1, Figure 2. and Figure 3).

  1. Radial-Cephalic fistula, (RC AVF) (Figure 1) is the most common native vein AVF and is described in detailed images below. The surgery is generally accomplished by an end vein to side artery anastomosis. The wrist radio-cephalic fistula was first performed by Kenneth Appel, a New York surgeon in 1965. The anastomosis was side to side between the radial artery and the cephalic vein and a 3–5 mm anastomosis using silk sutures in a continuous fashion. Anecdotally, the outcomes of this historic small series were impressive with a primary patency of 12/14 (86%). This classic Brescia-Cimino AVF used a side vein to side artery anastomosis, which often led to venous hypertension in the hand from incompetent valves in the cephalic vein distal to the anastomosis. The distal radial artery used as inflow results in lower blood flow than the brachial artery based AVF. When Radio-cephalic (RC) AVF is used as the first hemodialysis HD), the upper arm vessels are enlarged over time from high blood flow and must be preserved for later use if needed. This is referred to as “secondary fistula” as the outflow vein upper arm cephalic or the basilic veins are dilated from this forearm AVF. We will describe the principal detailed techniques for making the RC AVF anastomosis (Figures 6-31). Most technical steps can be generally applied for other AVF anastomoses sites. 
  2. The Brachial-Cephalic fistula (BC AVF) (Figure 2) requires less dissection than a brachio-basilic transposition (BVT) (Figure 3) where the entire vein needs to be mobilized and transposed closer to the skin. The distal brachial artery upper arm AVFs have a higher blood flow than the RC AVF, and a higher incidence of steal syndrome between 5-10%. (Reference 1). The proximal radial artery at the elbow is sometimes used for anastomosis rather than the brachial artery in cases of upper arm cephalic vein, although, this is generally still referred to as a brachial-cephalic (BC) AVF).  Compared to distal brachial artery proximal radial has less risk of development of Dialysis Access Steal Syndrome (DASS) 
  1. Brachial-Basilic AVF (Figure 3) involves variations of basilic vein transposition (BVT) or superficialization. The BVT procedure requires more surgical skills because of its complex and variable anatomy adjacent to upper arm vital structures such as the brachial artery, the median nerve and the medial brachial sensory nerve and the median cutaneous nerve of the forearm. (Video links 1-19).

The vein must be both elevated (superficialized) and transposed to a more lateral position to enable repeated cannulations. Since the basilic vein is less accessible for veno punctures it is usually well preserved except for the increasing use of peripherally inserted central catheter (PICC) lines. When the proximal radial artery is used for anastomosis in upper arm fistulae the risk of distal ischemia is decreased.

Order of Preference in Fistula Creation. Various societies guidelines suggest the order of AVF preference with the rationale of ease of construction and less patient morbidity are depicted in Table 2.  One such rule is to start distally to preserve more proximal veins for future use. It is our opinion that individual patient factors and circumstances must take precedence over simplistic intuitive guidelines. The access choice must be adapted to each patient and circumstances at the time of presentation and based on the dialysis access mission statement of doing the right thing, to each patient at the right time in the right amount guided by society laws where you live (Reference 2).

For discussions of dialysis access algorithms, the reader is referred to: Chapter 2 in www.kidneyacademy.com, Renal Replacement Therapy Algorithms.

Table 2. The suggested or preferred order of preference for AVF    

  1. Radial-Cephalic AVF (Figure 1)
  2. Brachio-cephalic AVF (Figure 2)
  3. Basilic vein Transposition AVF (Figure 3) and (Reference 3)

Fistula Maturation. There is no uniform definition for AVF maturation except successful repeat cannulations.  First, it must have adequate blood flow of 600 ml/min to support dialysis and second, it should be of adequate diameter of 6 mm diameter to allow for needle size between 14-16 g. Characteristics of usable fistula requirements for successful cannulation is popularized as the “Rule of 6” that considers blood flow, fistula vein diameter, depth, and cannulation segment length assessed at 6 weeks after creation (Table 3).

 

TABLE 3. The “RULE of 6s”

  1. The AVF within 6 mm below the skin surface for reliably cannulation
  2. At least 6 inches (10-15 cm) of vein length available for cannulation
  3. Blood flow of 600 ml/min, in the artery proximal to the anastomosis
  4. A fistula vein inner diameter of at least 6 mm

 

Blood flow adequate to support dialysis varies with location practices. To be used as dialysis access, the AVF must be able to sustain the blood of about 500-600 mL/min is the minimum required for adequate dialysis. This is related to body size and the duration of each dialysis treatment. With longer dialysis treatment times of 4-6 hours practiced in some countries, a fistula flow of 250-300 ml/min may suffice. (Document 3).

Size Adequate to Permit Repetitive Cannulation for successful long-term dialysis, the AVF must have an inner diameter that will permit repetitive cannulation. To do this, the staff must be able to see or at least feel the vein.  The consensus is a minimum cannulation diameter of 5-6 mm.

Fistula Vein Depth under skin surface presents two problems. First, the standard dialysis needle is only 1¼ inch (3.2 cm) in length. Second, access vein needs to be palpable by the cannulating individual. Various surgical methods have been used to make the vein more superficial, including liposuction. Perhaps the most important factor is selection of an access vein that is less than 6 mm under the skin surface and with a cannulation length of at least 10 – 15 cm or 6 inches. Other dialysis options such as peritoneal dialysis must be considered in a structured analysis approach to ESRD treatment options (ref).

Segment for Cannulation must have a relatively straight segment available for repeated two needles. At a minimum, this should be 10 – 15 cm in length. This length is necessary because cannulation sites must be rotated to preserve the AVF long-term repeat cannulations. This requires space, as the dialysis needle must be inserted a short distance inside the vein to be stable during the dialysis session. Attempts at cannulation into a tortuous AVF are often met with disaster. Unfortunately, a straight segment is not always present. In these cases, it may be possible to straighten the vein by surgical intervention.

Time to Maturation. The percentage of fistula that matures and the time it takes is quite variable. AVFs that will mature do so within 4-6 weeks.  There are several less controlled factors that delay fistula cannulation. (Figure 4) Common potential hurdles to access maturation include a delay of about 1 month from being referred between specialties such as surgical evaluation. Second, there is a delay of up to 4 months for scheduling surgery. Finally, another 7 months delay ensues before the fistula matures, that is being used for dialysis. It should be noted that about 30-50% of AVFs are never used.

The image (Figure 4) illustrates flagrant examples of common systems lacking structured planning for optimal outcome. 

Figure 4

This image depicts common hurdles to access maturation. First, there is often a delay of about 1 month from being referred (red line) to being seen (blue line) for surgical evaluation. Second, there is a delay of about 4 months for surgical scheduling (the green line) for AVF surgery. Finally, there is another 7 months delay before the fistula matures, that is being used for dialysis (bottom light blue line). It should be noted that about 30 – 50 % of AVFs have primary failure and therefore never mature or used

Figure 4

System designs such as referral patterns, institutional, regional and country policies, culture and “intuitions” are influential forces for ESRD treatment options and outcomes.   The image (Figure 4) is an example of a system lacking structured planning for optimal outcome (1).

Nephrology Referral patterns greatly affect outcomes including sepsis from prolonged use of central vein catheters (1-4). Planning is key to changing these adverse outcomes.  Patients who see a nephrologist prior to the need for dialysis start dialysis more often with AVF as a permanent access (2,3,5).

Optimal time for Access placement timing is complex partly because of the unpredictable decline in renal function. As a rough guide creatinine clearance of 15–20 ml ⁄ minute or serum creatinine of 3.4–5.6 mg⁄ dl, stage 4 of Chronic Kidney Disease (CKD) and the size and weight of the patient should initiate referring to the nephrologist or surgeon for vascular access when they reach (glomerular filtration rate <30 ml/min/1.73 m2) or earlier in case of rapidly progressive nephropathy or specific clinical and local facilities. This concept was included in the 2019 update of KDOQI guidelines (7).

To improve the planning and timing of access placement the Kidney Failure Risk Index (KFRI) may be used. Although not validated in this setting, the KFRI gives a time prediction of reaching end stage renal disease within 2 and 5 years. KFRI is age, GFR and proteinuria dependent (7-13).

Atraumatic surgical technique is of paramount importance in dialysis access as patients are often elderly and with comorbidities. The recent innovations with percutaneous peritoneal dialysis catheters using strict catheter technique and the percutaneous AVF techniques have made placement less traumatic and expanding indications to the very ill patients and being performed with ultrasound and fluoroscopic guidance under local anesthesia.   These techniques require technical skills and team cooperation. The real-world outcome remains uncertain. The cost of devices and added procedures required for maturation and patency may prevent widespread application.  These techniques are summarized in Document 6.

 

  1. Lee, T, Barker, J, Allon, M. Tunneled catheters in hemodialysis patients: reasons and subsequent outcomes. Am J Kidney Dis 2005; 46:501
  2. Astor, BC, Eustace, JA, Powe, NR, et al. Timing of nephrologist referral and arteriovenous access use: the CHOICE Study. Am J Kidney Dis 2001; 38:494.
  3. Lee, T, Barker, J, Allon, M. Associations with pre-dialysis vascular access management. Am J Kidney Dis 2004; 43:1008.
  4. Lee, T, Barker, J, Allon, M. Tunneled catheters in hemodialysis patients: reasons and subsequent outcomes. Am J Kidney Dis 2005; 46:501
  5. Astor, BC, Eustace, JA, Powe, NR, et al. Timing of nephrologist referral and arteriovenous access use: the CHOICE Study. Am J Kidney Dis 2001; 38:494.
  6. Lee, T, Barker, J, Allon, M. Associations with pre-dialysis vascular access management. Am J Kidney Dis 2004; 43:1008
  7. NKF-K/DOQI Clinical Practice Guidelines for Vascular Access: Update 2006. Guideline 1: Patient preparation for permanent hemodialysis access.
  8. Jindal, K, Chan, CT, Deziel, C, et al. Hemodialysis clinical practice guidelines for the Canadian Society of Nephrology. J Am Soc Nephrol 2006; 17: S1.
  9. Tangri, N, Stevens, LA, Griffith, J, et al. A predictive model for progression of chronic kidney disease to kidney failure. JAMA 2011; 305:1553.
  10. Tangri, N, Grams, ME, Levey, AS, et al. Multinational Assessment of Accuracy of Equations for Predicting Risk of Kidney Failure: A Meta-analysis. JAMA 2016; 315:164.
  11. Cravedi, P, Remuzzi, G. Pathophysiology of proteinuria and its value as an outcome measure in chronic kidney disease. Br J Clin Pharmacol 2013; 76:516.
  12. Levey, AS, Cattran, D, Friedman, A, et al. Proteinuria as a surrogate outcome in CKD: report of a scientific workshop sponsored by the National Kidney Foundation and the US Food and Drug Administration. Am J Kidney Dis 2009; 54:205.
  13. Nitsch, D, Grams, M, Sang, Y, et al. Associations of estimated glomerular filtration rate and albuminuria with mortality and renal failure by sex: a meta-analysis. BMJ 2013; 346: f324
  14. Peeters, MJ, van Zuilen, AD, van den Brand, JA, et al. Validation of the kidney failure risk equation in European CKD patients. Nephrol Dial Transplant 2013; 28:1773.
  15. Hingwala, J, Wojciechowski, P, Hiebert, B, et al. Risk-Based Triage for Nephrology Referrals Using the Kidney Failure Risk Equation. Can J Kidney Health Dis 2017; 4:2054358117722782.
  16. Hiremath, S, Knoll, G, Weinstein, MC. Should the arteriovenous fistula be created before starting dialysis? A decision analytic approach. PLoS One 2011; 6: e28453. 

Patient Evaluation Prior To Access Placement in preparation is extremely important. Proper patient selection will materially enhance the opportunity to place an AVF. This evaluation must be detailed and complete. This is covered in depth in Chapter 2 of www.kidneyacademy.com

TABLE 4.   Principles of good practice for saving the veins for AVF  

  • Wear a Save the Vein wristband to alert health care providers
  • Use the dorsum of hands first for vein access
  • After starting dialysis, use wristband to protect access
  • Inform health care providers of vein preservation.

For in-depth physical examination in dialysis access the reader is referred to: www.kidneyacademy.com planned for Febr 2026

 

Table 5. Anatomical Requirements for a Fistula vary widely between institutions, affecting the AVF maturation process

Artery Requirements

  • A feeding artery with unobstructed flow
  • Patent palmar arch(es)
  • Luminal inner diameter 5 mm or greater at anastomosis site

Vein Requirements

  • Luminal inner diameter 4-5 mm or greater at anastomosis point
  • Absence of obstruction/stenosis on preop ultrasound mapping
  • Straight segment for cannulation of 10 – 15 cm
  • Within 6 mm below skin surface
  • Continuity with proximal (central) veins

Various authors advocate different sizes of veins and artery suitable for AVF formation. While technically the anastomosis of vessels smaller than those stated in Table 6 can be performed, the maturation of such fistulas is unpredictable and often poor. Technical vascular surgical challenges do not always translate into good patient outcomes.

For a fistula to mature requires suitable inflow, a suitable vein conduit and unrestricted low resistance outflow. The blood flow increase through the inflow artery is rapid and within 24 hours the brachial artery flow increases 10-fold from normal 40 – 50 ml/min to almost 400 ml/min and up to 20 times after 8-9 months (Figure 5). (14-17) 

Figure 5

Blood volume flow changes over time after surgical placement of an AVF. The blood flow increase is over 500% in the first 24 hours after placement and reaches a flow of at least 500 ml/min after one month. (Courtesy Dr G. Beathard)

Figure 5