1. When to first cannulate Vascular Access for Hemodialysis Müjdat YENİCESU, M. D. October 23, 2014

2. Vascular Access (VA) is still the Achilles’ heel of long term hemodialysis (HD) therapy. NKF DOQI guidelines recommend AVF as the first choice of primary VA for HD therapy. VA cannulation involves inserting two, occasionaly one, large bore needles into the fistula veins. The native vein has a rather thin wall and is relatively fragile. Once a fistula created, it must develop to the point that it is usable. The AVF must be adequately mature to allow repeat cannulation. Optimal waiting time before first use of VA is not known. Early cannulation has been shown to be associated with shorter survival. Introduction

4. AJKD, 1995, 26:341-346

7. AJKD, 2002, 40: 1264-1276

9. Creation, cannulation and survival of AVF:data from the DOPPS. KI, 2003, 63(1):323

11. 14

12. Creation, cannulation and survival of AVF:data from the DOPPS. KI, 2003, 63(1):323

13. This group reported (2002) that the presence of temporary catheters at the hdx initiation was associated with earlier cannulation and shorter survival of the first AVF created for incident patients. They explained this relationship with insufficient maturation period because of catheter complications.

14. Figure 1. Kaplan-Meier curves of time to failure (primary patency from first cannulation) by use of catheters (CVC) at dialysis start (A) and by maturation category in days (B). Ravani P et al. JASN 2004;15:204-209 ©2004 by American Society of Nephrology

15. AVF maturity; How do we know AVF is mature enough for cannulation? The high pressure and flow artificially introduced when a fistula is created causes the involved vein to undergo a series of changes characterized by dilation and thickening of the wall. This process, reffered to as maturation, eventually renders the fistula usable as a vascular access. Data suggest that adequte fistula size and blood flow helps predict fistula maturation. An experienced dialysis nurse were also 80 % accurate in predicting the ultimate utility of a fistula for dialysis.

16. Radiology, 2002;225(1):59/Hdx arteriovenous fistula maturity: US evaluation

17. NKF-KDOQI Vascular Access 2006 Work Group Membership

18. Another rule; Arterialized vein intima-media (IMT) thickness of >0.13 mms was associated with successful cannulation in a study of new AVFs using high frequency ultrasound. Seminars in Dialysis, 2013, 26(3):315-322. What Nephrologists Need to Know about Vascular Access Cannulation Radioloy, 2011, 261(2): 616-624. Arteriovenous fistulas for hemodialysis: application of high-frequency US to assess vein wall morphology for cannulation readiness

19. Cannulation before two weeks of age should be avoided. Cannulation between two to four weeks may be attempted but only if the fistula is considered mature. Cannulation after four weeks of maturation may be safe, if the fistula is mature. Conclusions relating to timing of cannulation of AV fistulas NDT 2005, 20(4): 688.