1129-7298/091-06$15.00/0

The Journal of Vascular Access 2007; 8: 91-96

Creation of secondary AV fistulas from failed hemodialysis grafts: the role of routine veinmapping

V.D. NGUYEN1, L. TREAT2, C. GRIFFITH3, K. ROBINSON3

1 Memorial Nephrology Associates, Olympia, Washington - USA and Fistula First Initiative, Leadership Group member2 Renal Care Group of the Northwest, Washington - USA3 Surgical Associates, Olympia, Washington - USA

Abstract: Pre-existing forearm grafts lead to dilatation of upper arm veins of the ipsilateral arm that greatly fa-cilitates the creation of secondary arteriovenous fistulas (AVF). In this retrospective review of 18 patients, theroutine and periodical revision of failed grafts were discontinued. Vein mapping by physical examination or Du-plex studies was performed prior to graft failure and a secondary AVF was created when the graft failed. Usingthis management strategy, an AVF creation success rate of 95% was achieved despite high incidence of co-morbidityfactors within the patient population. This success rate demonstrates the value of vein selection by vascular map-ping prior to graft failure and early vascular access planning in the successful creation of secondary AVF. (J VascAccess 2007; 8: 91-6)

Key words: Arteriovenous fistula, Hemodialysis vascular access, Quality improvement program of vascular access, Hemodialysisgraft, Hemodialysis catheter

© Wichtig Editore, 2007

INTRODUCTION

The types of permanent hemodialysis vascular accesscurrently in use are the native arteriovenous (A-V)fistulas, the polytetrafluoroethylene (PTFE) A-Vgrafts and the tunneled dialysis catheters. Multiplepublished studies have shown that the fistulas havesuperior four-to-five-year patency rate and requirefewer interventions compared to grafts andcatheters (1, 2). During the early 1990s, the use ofAVFs declined in the United States (3). Althoughduring 1997 through 1999, there was some increasein the percent of AVF procedures (from 29% in 1997to 36% in 1999) (4), there remains need for im-provement. Data from the 2003 Annual Report ofthe ESRD Clinical Performance Measurements Proj-ect compiled by the Centers of Medicare and Medi-caid Services showed that only 27% of incident and33% of prevalent HD patients were receiving dialysisusing an AVF at the end of 2002 (5). The NationalKidney Foundation Dialysis Outcomes Quality Ini-tiative (DOQI) Clinical Practice Guidelines work-group recommended an AVF placement goal of 50%

in all new patients, with an ultimate AVF prevalentrate of 40%. The Olympia (Washington) multidisci-plinary vascular access team implemented a numberof steps which resulted in the total elimination ofgraft use in our hemodialysis practice by the year2000 (6). The vascular access team decided to stoproutine revision of failed grafts and to facilitate sec-ondary AVF placement when a graft failed. Therewas no prior literature regarding the success of graftsto AVF conversion.

METHODS

Medical records of 18 patients undergoing graft tosecondary AVF creation between 1996 and 2000were reviewed retrospectively. Data collection in-cluded patient co-morbid factors, vein mapping re-sults, categories of AVF surgeries, success rates, andany ischemic complications. Prior to graft failure,routine monthly vein mapping by physical examina-tion with and without a tourniquet was done in allpatients with AV grafts by a single nephrologist. Out-

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Creation of secondary av fistulas from failed hemodialysis grafts: the role of routine vein mapping

flow veins, mostly upper arm cephalic and basilicveins were identified if they were superficial enough.Ink marks were made on each side of the veins atthree locations along the length of the vein. Exter-nal vein diameter was measured with a ruler and av-erage diameter was calculated. All measurementswere done without using a tourniquet. Occasionally,a forearm cephalic vein was adequately dilated bythe forearm grafts and could be used for AVF cre-ation. However, many patients had no superficialveins noted during routine physical examination. Inthese patients, duplex mapping was conducted tomeasure the diameter of arm veins and their depthbelow the skin. Duplex mapping was done by a sin-gle vascular ultrasound technologist. Criteria forveins suitable for AVF creation included a minimumvein diameter of 2.5 mm. Vein transposition was in-dicated for veins located at a depth of 10 mm ormore below the skin. For each patient with a graft,the nephrologists created a written long term accessplanning (Appendix: Dialysis Patient Vascular AccessPlanning). The access plan was updated monthlyand was made available to all members of the vascu-lar access team. Secondary AVF creation was doneonly when the AV graft failed. When grafts throm-bosed, they were no longer revised. The nephrolo-

gist called the vascular surgeon for a secondary AVFplacement within 72 hours with application of datafrom the patient’s long term care plan. The sametwo vascular surgeons performed all the surgeries.In patients with a superficial upper arm cephalicvein which could be cannulated immediately aftersurgery, AVF surgery was done electively before totalgraft thrombosis: i.e. when the graft showed the fol-lowing clinical signs of impending failure: the pres-ence of venous pressure higher than 100 at theblood flow rate of 200 ml/min, water hammer pulseinstead of access thrill on palpation, difficulty withcannulation and prolonged bleeding from accesspuncture sites after completion of dialysis. The following are brief descriptions of surgical pro-cedures for creation of secondary upper arm AVFfrom forearm grafts:1. Brachio-basilic AVF with transposition (Fig. 1):an incision is made along the upper arm basilic vein.The collateral veins are ligated. A subcutaneous tun-nel is created anterolaterally to the incision site witha tunneler (Fig. 2). The distal end of the vein is tran-sected at the antecubital level if appropriate. Thevein is mobilized and pulled through the tunnel withthe help of the tunneler. After the anastomosis tothe brachial artery, the incision is closed.2. Brachio-cephalic AVF

a. without transposition: In case the graft is stillpartially patent (Fig. 3), a 2 cm segment of the ve-nous end of the graft is resected; the new end ofthe graft is closed with a suture. The distal end of

Fig. 1 - Secondary transposed brachio-basilic AV fistula-left arm.

Fig. 2 - Detail of transposition procedure. Operating room pictureof a right arm primary transposed brachio-basilic AV fistula.

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the upper arm cephalic vein is transected, mobi-lized and anastomosed to the brachial artery. Ifthe graft is completely thrombosed, the distal endof the upper arm cephalic vein is transected andmobilized and anastomosed to the brachial arteryb. with transposition: an incision is made alongthe deep seated cephalic vein. The vein is dis-sected and its collateral veins are ligated. A sub-cutaneous tunnel is created away from theincision with a tunneler. The distal end of upperarm cephalic vein is transected. The vein is mo-bilized and pulled through the tunnel with thehelp of the tunneler. After the anastomosis to thebrachial artery, the incision is closed. If the vein was superficial and could be cannu-lated within 24 hours, no hemodialysis catheterwas needed. If the surgeon was not available atthe time of the graft thrombosis, a temporarycatheter was used till surgery. However, a tun-neled catheter was placed before or at the timeof surgery if transposition of the deep vein wasneeded. Whenever possible, catheters wereplaced in the internal jugular vein, contralateralto the prospective fistula placement site.

RESULTS

This group of patients had severe co-morbid factorswhich would tend to affect adversely the success ofAVF placement (Tab. I): older age and diabetes mel-litus. A majority (83.3%) had ischemic vascular dis-eases (coronary artery disease, stroke, or limbischemia). Many patients had multiple ischemic vas-cular diseases: 11% had all three, 50% had two ofthe above-noted diseases. Half of all patients in the study required Duplexmapping. The diameter of the preoperative outflowbasilic and cephalic veins as measured by Duplex orphysical exam was 4.8 mm (SD 1.1) prior to graftthrombosis. A total of 18 AVF were created. Number of surgicalprocedures: 18. 95% of AVFs were used successfullyfor dialysis. One AVF (brachio-cephalic) developedearly stenosis, 2 cm above the anastomosis which wasdiagnosed by physical examination and confirmedby a Doppler study. A surgical revision (vein bypassgraft) was performed. The AVF restenosed within 4weeks and did not mature when patient died 3months later from an ischemic coronary event. Thedefinition of fistula creation success is its satisfactoryuse over the patient lifetime or till final fistulathrombosis to provide adequate blood flow rate(usually between 300-400 ml/minutes) and ade-quate dialysis dose as defined by the National Kid-

Fig. 3 - Secondary brachio-cephalic AV fistula-left arm, withouttransposition.

TABLE I - PATIENT DEMOGRAPHICS AND CO-MORBIDFACTORS

Age: 69.9 (SD 8.1)

Sex: 56% female

44% male

Co morbid factors:

Diabetes mellitus: 66.6%

Ischemic Cardio-vascular diseases: 83.3%

coronary artery disease 61%

stroke 44%

limb ischemia 50%

TABLE II - TYPES OF FISTULA CONVERTED FROMGRAFTS*

Radio-cephalic: 5.6%

Brachio-cephalic: 55.6%

Brachio-basilic: 38.8%

*Remark: 50% of all fistulas were transposed

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Creation of secondary av fistulas from failed hemodialysis grafts: the role of routine vein mapping

ney Foundation DOQI Guidelines on Adequacy ofdialysis dose. A large majority of the AVF (Tab. II)were created from forearm grafts, only 1 case froman upper arm graft. All secondary fistulas, except forone, were upper arm AVF, either brachiocephalic orbrachio-basilic, reflecting the arterialization ofupper arm outflow veins by forearm grafts. In fact, areview of all patients (total 49) on hemodialysis dur-ing the study period shows that both secondary andprimary AVF were also predominantly upper armAVF: 64.6% (6). In elderly, ischemic patient popula-tion like ours, distal radio-cephalic AVF is only pos-sible in a minority of patients. Mean time to successful cannulation was 34.1 days(SD 25, range: 1 to 56 d) after its placement. Fivenon-transposed brachiocephalic AVFs were success-fully cannulated within 1 day of their placement.The criteria for early cannulation were subjective.Both the dialysis staff and the nephrologist per-formed physical examination of the veins before andafter surgery and reached the early cannulation de-cision by consensus based on how superficial theveins were. The predictive value by physical exami-nation by experienced staff was excellent: 5 out of 6.First time cannulation blood flow rate was limited to200 ml/minute using 17 gauge needles. Needle sizeand blood flow rate were increased gradually to 15gauge and up to 400 ml/minute. Steal syndrome was present in 18% of all fistulas andwas successfully treated with vein banding proximalto the anastomosis. None required ligation of AVF.

DISCUSSION

The presence of a forearm PTFE graft may offer agreat opportunity to create a secondary proximal AVfistula. The upper arm cephalic and basilic veins areoften well arterialized by the presence of the AV

Fig. 4 - The presence of a forearm graft has lead to large superfi-cial upper arm and forearm cephalic veins. After the graft fails, asecondary brachio-cephalic AVF could be placed and used imme-diately after surgery without the need of transitional dialysiscatheter. Alternatively, a distal radio-cephalic vein could also beplaced.

Fig. 5 - The presence of a forearm graft has lead to large superfi-cial upper arm basilic vein. After the graft fails, a secondary trans-posed brachio-basilic AVF could be placed and used 2 months aftersurgery. A transitional tunneled dialysis catheter will be needed.

Fig. 6 - Doppler mapping of a 72-year-old female patient. The first number indicates vein diameter in mm, the second onevein depth. The number in parenthesis indicates vein diameterafter compression by a tourniquet. The presence of right forearm loop graft (drawing in black) hascaused significant dilatation of the upper arm cephalic and basilicveins up to 100% as compared with the left upper arm veins.

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graft and may be dilated well enough for the suc-cessful placement of brachiocephalic (Figs. 4-6) orbrachiobasilic AV fistulas. Outflow vein diameters av-eraged 4.8 mm. Since mature AVF is defined as hav-ing a diameter of at least 4 mm (7), these veins werealready matured before AVF surgery. In fact, the suc-cess of AVF creation depends on vein size, with min-imum diameter of 2.2 mm in one study (8) and theability of the arterial and venous vessels to dilateunder the influence of the increased shear rates(vessel remodeling) (8). In addition, higher arterial blood pressure and flowrate (brachial artery) allow a more rapid maturationof antecubital AVF and higher maturation rate com-pared with distal radiocephalic AVF (9, 10). Pre-Access failure Vein Mapping plays a critical rolein AVF creation from failed grafts. Vein Mapping canbe done by careful and periodical physical exami-nation. However, physical exam alone was inade-quate in as many as 50% of patients in ourexperience. These patients did not have a suitablesuperficial vein due to obesity or to the nature of thevein. Most upper arm basilic veins required Duplexmapping since they run a superficial course onlyalong the lower part of the upper arm then divedeep inside to join the deep brachial vein. The meas-ured length of the basilic vein must be adequate toallow its transposition to a more superficial positionin the antero-lateral position of the upper arm.Doppler may also detect vein stenosis prior to sur-gery and improve surgical outcome or influence thechoice of blood vessels. Doppler vein mapping is alsoimportant in other investigators’ experience (11-13),especially in patients at risk of maturation failure: di-abetic, elderly, peripheral vascular disease, obese etc.Pre-op physical examination alone failed to identifysuitable veins for AVFs in 58 patients out of a total of108 patients in one study (11). Indeed, pre-opDoppler assessment of vessels reduced early failureof AVFs significantly, from 36% to 8.3% (11). DuplexUS is the most efficient method to assess vein diam-eter, depth, and integrity. In addition, more recentresearch suggests that artery size and function studyby Doppler are equally important (8). Our team nowuse Duplex mapping of arm veins and arteries in allpatients with high co-morbid factors, even in thosewith apparently adequate superficial veins. It is important that vascular access management plan(graft to AVF creation plan) be made long beforegrafts show any signs of failure and be available tothe whole team at all time since graft may thrombosewhen the primary nephrologist is not on call. Afterthe graft thromboses, the arterialized upper armveins may collapse due to decreased intravenouspressure and blood flow rate and may no longer be

prominent even on venogram or Duplex study.Therefore, the on call team may not be able to in-tervene without the vascular access managementplan of that particular patient. Steal syndrome was not a major issue (18%) despitehigh risks of ischemia in this group of patients withmultiple comorbid factors. The AVF anastomosis sizewas kept small (less than 4 mm) and distal arterialflow monitored with Doppler during surgery. Thosepatients with steal syndrome underwent successfulvein banding proximal to the anastomosis and didnot require ligation of the AVFs.The very high success rate of secondary AVF cre-ation in this study despite high patient co- morbidfactors suggests that pre graft failure vein mappingeither by physical exam or by Doppler may play a pri-mary role in the successful secondary AVF creationfrom failed grafts. However, the present investigationis not a controlled study, and the patient populationsize is small, all with high co-morbid factors. Thefindings of this study will require confirmation by fu-ture randomized studies involving a larger patientpopulation with a greater spread of co- morbid con-ditions. Of note, Fistula First Initiative has also rec-ommended the routine creation of secondary AVFfrom failed grafts (www.FistulaFirst.org).Finally, we do not recommend routine placementof grafts in order to convert them later into sec-ondary AVF. Since we establish a collaborative mul-tidisciplinary vascular access team in our programto promote early referral of kidney patients tonephrology service, preservation of arm veins, rou-tine use of Duplex mapping and innovative surgi-cal strategies, we no longer use graft in our patientpopulation despite the high incidence of co-mor-bid factors (6).

CONCLUSION

Pre-existing grafts lead to arterialization and dilata-tion of veins in ipsilateral arm and facilitate greatlythe creation of secondary AVF. The surgical successrate was 95% in our experience despite high inci-dence of morbidity factors among our patients. TheAVF success rate was dependent upon effective veinselection for AVF creation done prior to AV graft fail-ure and upon the development of an individualizedlong term vascular access plan which was availableto all members of the vascular access team.

ACKNOWLEDGMENTS

Illustrations were done by Paul Bunning (Bunning@aol.com)

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Creation of secondary av fistulas from failed hemodialysis grafts: the role of routine vein mapping

Address for correspondence:Vo D. Nguyen, MDMemorial Nephrology Associates500 Lilly Rd, Suite 203Olympia, WA 98506 - USAvdnguyen9@pol.net

Part of this abstract was presented at the 2000 American Societyof Nephrology Annual Meeting Poster session in Toronto,Canada.

REFERENCES

1. Woods, JD. Tureene MN, Strawderman RL, YoungEW et al. Vascular access survival among incident he-modialysis patients in the United States. Am J KidneyDis 1997; 30: 50-7.

2. Churchill DN, Taylor DW, Cook RJ, Laplante P et al.Canadian hemodialysis morbidity study. Am J KidneyDis 1992; 19: 214-34.

3. Kaufman JL. The decline of the autogenous he-modialysis access site. Semin Dial 1995; 8: 59-61.

4. Eggers P, Milam R. Trends in Vascular Access Proce-dures and Expenditures in Medicare’s ESRD Pro-gram, in Vascular Access for Hemodiaysis, edited byHenry ML, edition 7, Chicago, W. L. Gore & Associ-ates Inc. and Precept Press, 2001, pp 133-43.

5. 2003 Annual Report-ESRD Clinical PerformanceMeasures Project. Department of Health and HumanServices-Center of Medicare & Medicaid Services, De-cember 2003, p 24

6. Nguyen VD, Griffith C, Treat L. Multidisciplinaryteam approach to increasing AV fistula creation. Acommunity-based nephrology practice experience.Nephrology News & Issues 2003; 17: 54-61.

7. Robbins ML, Chamberlain NE, Lockhart ME, Galli-chio MH, Young CJ, Delerhoi MH, Allon M. He-modialysis arteriovenous fistula maturity: USevaluation. Radiology 2002; 225; 59-64

8. Malovrh M. Native arteriovenous fistula: preoperativeevaluation. Am J Kidney Dis 2002; 39: 1218-25.

9. Rodriguez J, Armadans L, Ferrer E, Olmos A, et al.The function of permanent vascular access. NephrolDial Transplant 2000; 15: 402-8.

10. Hakaim A, Nalbandian M. Superior maturation andpatency of primary brachiocephalic and transposedbasilic vein AVF. J Vasc Surg 1998; 27: 154-7.

11. Silva M, Hobson R, Pappas P, Haser P, et al. A strategyfor increasing use of autogenous hemodialysis accessprocedures: Impact of preoperative noninvasive eval-uation. J Vasc Surg 1998; 27: 302-8.

12. Ascher E, Gade P, Hingorani A, Mazzariol F, et al.Changes in the practice of angioaccess surgery: Im-pact of dialysis outcome and quality initiative recom-mendations. J Vasc Surg 2000; 31: 84-92.

13. Allon M, Lockhart ME, Lilly RZ, et al. Effect of pre-operative sonographic mapping on vascular accessoutcomes in hemodialysis patients. Kidney Int 2001;60: 2013-8.

APPENDIX:

COPY OF DIALYSIS PATIENT VASCULAR ACCESS PLAN-NING

VASCULAR ACCESS CHECK LIST

Patient Name:

Nephrologist:

Primary Care Physician:

Previous or Current access: Date:

Vein mapping: date:best vein: size: Depth:2nd best vein: size: Depth:

Surgeon: Appointment date:

Surgery Plan A:

Surgery Plan B:

Tunneled catheter needed: