|Year : 2021 | Volume
| Issue : 2 | Page : 134-138
Outcome of prosthetic arteriovenous graft in lower limb for hemodialysis: A series of 10 patients
Mohd Azam Haseen1, Mayank Yadav1, Sumit Pratap Singh1, Renu Yadav2
1 Department of CTVS, Jawahar Lal Nehru Medical College and Hospital, AMU, Aligarh, Uttar Pradesh, India
2 Department of Radiology, Vardhman Mahavir Medical College and Safdarjung Hospital, New Delhi, India
|Date of Submission||21-Jun-2020|
|Date of Acceptance||07-Jul-2020|
|Date of Web Publication||13-Apr-2021|
Department of CTVS, Jawahar Lal Nehru Medical College and Hospital, AMU, Aligarh, Uttar Pradesh
Source of Support: None, Conflict of Interest: None
Background: The burden of chronic kidney disease and the incidence of end-stage renal disease in India are continuously increasing. For each of these patients, adequate vascular access for dialysis is essential for survival. Access to patients' blood can come in the form of a catheter, native arteriovenous fistula (AVF), or prosthetic graft. It is apparent that the number of new “incident” patients and “prevalent” patients will continue to increase, requiring stable forms of vascular access. An alternative to autologous AVF is placement of a synthetic vascular graft prosthesis. Methods: This is a retrospective study which aims to evaluate the outcome of 10 consecutive patients with arteriovenous grafts (AVGs) made for hemodialysis in patients with exhaustive veins/failed AVFs with central venous catheters (CVCs) in situ. Results: The mean age of patients in our study was 54 years. The primary patency rate of AVGs was 50% and 30%, whereas the secondary patency rate was found to be 80% and 60% at 6 months and 1 year, respectively. Conclusion: AVGs can be used as an alternative to AVFs with acceptable results.
Keywords: Arteriovenous grafts, hemodialysis, outcome
|How to cite this article:|
Haseen MA, Yadav M, Singh SP, Yadav R. Outcome of prosthetic arteriovenous graft in lower limb for hemodialysis: A series of 10 patients. Indian J Vasc Endovasc Surg 2021;8:134-8
|How to cite this URL:|
Haseen MA, Yadav M, Singh SP, Yadav R. Outcome of prosthetic arteriovenous graft in lower limb for hemodialysis: A series of 10 patients. Indian J Vasc Endovasc Surg [serial online] 2021 [cited 2021 Jun 24];8:134-8. Available from: https://www.indjvascsurg.org/text.asp?2021/8/2/134/313572
| Introduction|| |
Hemodialysis (HD) trend in India has shown a significant proportion of young patients, especially diabetics requiring long-term dialysis. Vascular access-related morbidity remains the major impediment to full rehabilitation of the chronic HD patient. This has led to an increased requirement of more complex vascular access modalities for long-term HD. Prosthetic arteriovenous grafts (AVGs) can be considered as one such option but are associated with increased morbidity with an inferior primary and secondary patency as compared to autogenous arteriovenous fistulas (AVFs).,,,
In spite of being an established practice, “fistula first” strategy may not be universally applicable in patients undergoing HD, either because of nonsuitable veins or the maturation issues in AVFs leading to long-term Central venous cathete (CVC) exposure. Another important issue is that patients not currently on dialysis but needing HD in the near future do not consult a vascular specialist for arteriovenous (AV) access unless their dialysis starts. Hence, when these patients come to a vascular surgeon, already few of their autogenous AV access sites are either temporarily or permanently not usable. Paradigm innovation has modified the “fistula first” into “fistula first, catheter last” in which AVGs find a re-entry as an important tool in the above subsets of patients undergoing HD.
In this study, we aim to evaluate the outcome of consecutive ten patients of AVGs requiring HD.
| Methods|| |
The study was conducted at our single center from January 2017 to January 2019. This retrospective study included ten consecutive patients in whom AVGs were made as a permanent access for HD between right common femoral artery and vein. The reason for performing AVGs for HD in our study was failed AVF/exhausted AV access sites in the upper limb.
The graft material used was polytetrafluoroethylene (PTFE) Impra: BARD/Impra Inc., Tempe, AZ, with addition of an expanded cuff to a PTFE graft (Venaflow) to obviate the problem of outflow venous stenosis. All patients were hospitalized, and after due preanesthetic clearance, surgery was done under spinal anesthesia. Both femoral artery and vein were exposed, and graft was tunneled in subcutaneous plane in semicircular fashion. After heparinization, vessels were opened in between clamps. Venous anastomosis was done first with broader end of graft using 6-0 prolene in running fashion. Arterial anastomosis was done in a similar fashion and after de-airing clamps were released. Hemostasis was achieved and wound was closed in layers. Thrill in the graft was checked along with distal flow in the popliteal artery to check for any steal. Patients were kept hospitalized for 3 days to give injectable antibiotics and unfractionated heparin in a dose of 100 IU/kg 8 hourly for 72 h.
All patients were discharged on a single antiplatelet drug as well as on low-dose warfarin to keep the international normalized ratio between 1.5 and 2. Patients were followed up every month till 1 year to look for graft patency and any intervention required if the graft is not working.
Time to primary access patency was defined as the length of time between access placement and either permanent failure or first revision requiring a procedure to restore or maintain patency. An access revision was considered to have occurred when the access failed, and a thrombectomy, thrombolysis, angioplasty, or major revision was needed. Time to secondary access patency was defined as the length of time between access placement and permanent failure of the access. Access failure was considered to have occurred when a new vascular access was created or when a venous HD catheter was inserted.
Primary and secondary graft patency rates were analyzed using the Kaplan–Meier method. The frequency of access intervention was calculated by dividing the total number of procedures by the total years of access patency.
| Results|| |
The study consisted of ten patients who underwent placement of a permanent dialysis access in the form of AVG on the right side from the femoral artery to the femoral vein and whose access was subsequently used successfully for HD.
The mean age of patients in this study was 54 years (44–67 years). Other demographic data and clinical characteristics observed in these patients are summarized in [Table 1].
The primary patency rate of AVGs was 50% and 30%, whereas the secondary patency rate was found to be 80% and 60% at 6 months and 1 year, respectively [Figure 1].
The rate of interventions per year was 1.1, with synthetic PTFE graft used as a permanent access for HD. Seven out of 10 (70%) grafts required thrombectomy 11 times to resume patency of the grafts. The number of grafts requiring intervention was (70%), but because of the need for repeat procedures, the rate of intervention was high, as shown in [Table 2]. Despite the increased number of interventions, the resultant secondary patency at 1 year was 60% as compared with the primary patency of 30%.
The surgery for AVGs is quite safe, and no unexpected or catastrophic complications were experienced in our study. Prolonged bleeding because of increased venous resistance which was repaired by revision was reported as a bleeding event. The incidence of thrombosis was 1.3 events per year, and the incidence of infection was 0.2 events per year. The linearized rate of all events was 1.8 events per graft year [Table 3]. Few of the complications are shown in [Figure 2],[Figure 3],[Figure 4],[Figure 5].
|Figure 4: Image showing removal of thrombus from the thrombosed arteriovenous graft|
Click here to view
A total of 40% ( n = 4) of synthetic grafts used for AVGs were abandoned. The primary causes of abandonment were thrombosis and infection. One graft was explanted as a result of infection after 5 months.
| Discussion|| |
Expanded PTFE was first used as a conduit for vascular access in late 1970 and has since become the most popular graft material, despite its high incidence of occlusion (usually due to myointimal hyperplasia at the venous end), seroma formation, high infection rates, and suboptimal patency rates.
Patients with AVF as compared to AVG require much more interventions before successful access cannulation. This advantage of AVG was counterbalanced, however, by the higher rate of interventions required to maintain long-term AVG patency after successful use.
The indication for prosthetic AVG includes: failed AVF/exhausted superficial veins; lack of suitable vessels, particularly in elderly and diabetic patients; destroyed vessels by indiscriminate venipuncture; late referral for vascular access; need for immediate cannulation with avoidance of a central venous catheter (relative indication); and children who cannot tolerate multiple painful venipuncture associated with autogenous AVFs.
Although insertion sites in the upper limb are preferred because of the lower risk of associated sepsis, when the upper limb sites are exhausted, the thigh is the next favored site.,,
The major drawbacks associated with synthetic grafts are stenosis with or without graft thrombosis, infection, and vascular steal syndrome. Other complications include venous hypertension, pseudoaneurysm formation, and neurological disorders.
AV grafts begin to thrombose at flow rates <600 ml/min well above the level required for adequate dialysis (300 ml/min). Thrombosis is usually due to outflow tract obstruction in most cases, although in about 20%, no identifiable cause is found. Potential causes include dehydration, hypotension, compression during sleep, and excessive pressure to stop hemorrhage postvenipuncture or dialysis. Intimal hyperplasia is responsible for stenosis at the graft-vein anastomosis. Efforts at reducing the incidence of intimal hyperplasia have evolved from research into the following concepts: flow diffuser, graft geometry, and anastomotic geometry. Treatment options include surgical thrombectomy, mechanical thrombectomy, and pharmacomechanical thrombolysis. Green et al. in their randomized controlled trials concluded that surgical thrombectomy gave superior results to other forms of treatment. Dialysis can be resumed immediately after surgical thrombectomy without the need for an interim dialysis catheter, and the procedure is less painful and poses less risk of complications for the patient, although various studies suggest that the results of pharmacological thrombolysis are comparable to those of surgical thrombectomy.,
PTFE usage compared to autogenous AVF is associated with a five-fold increase in access infection., The risk factors for AV graft infections include diabetes mellitus, insertion in the thigh, history of multiple infections, number of surgical revisions, immunocompromised state, obesity, and thrombosed, abandoned AV grafts.,, Infection is a common cause of graft loss. The critical issues in the management of AV graft infection are the need to eradicate infection and to achieve HD with reduced morbidity. Treatment involves intravenous antibiotics, and graft excision may be required in some patients.
A less common, but more challenging, complication of AV grafts is symptomatic extremity ischemia caused by the diversion of arterial flow through the access site. The risk factors for steal (distal hypoperfusion ischemic syndrome) include female gender, age >60 years, diabetes mellitus, previous operations on the same limb, and the use of a brachial instead of the radial artery. In a recent review of the subject, Malik et al. described three etiological entities for vascular access associated steal: arterial stenosis, high fistula flow, and lack of vascular adaptation or collateral flow.
Limb swelling, hyperemia, and pain after AV graft insertion usually signify hypertension within the venous system. When limb swelling occurs distal to the site of the prosthetic graft, it is often due to incompetent valves in the deep venous system. However, if swelling involves the whole of the upper limb, central vein stenosis is the cause.
Pseudoaneurysm: Pseudoaneurysms have been reported in about 16% of thigh PTFE grafts. They are formed due to repeated puncture of grafts for HD.
Primary failure (failure within 30 days or before use for dialysis) of dialysis AV graft is often caused by technical problems influenced by surgical access construction, patient demographics, comorbidity, and graft loss due to premature cannulation and hematoma formation.,
Previous studies have reported the primary patency rates of PTFE AVGs as 28% at 12 months and 24% at 2 years  with secondary patency rates of 76% at 6 months, 55%–59% at 12 months, ,, and 43% at 24 months, respectively. It corresponds to the result of our study.
Thrombosis and/or stenosis account for most causes of AV graft impairment or loss. Uncorrected stenosis is associated with eventual AV graft thrombosis. Access surveillance coupled with radiological or surgical intervention has been known to prolong access life.,
The major limitation of this study is very small patient population, and it is not good to conclude on the basis of this small study population, although the results of this study are similar to other major studies.
| Conclusion|| |
The use of synthetic AV grafts for vascular access is associated with a number of advantages. AV grafts are technically easier to cannulate as it has a large surface area for cannulation and offers a shorter maturation period. The main disadvantages include the development of graft stenosis, particularly at the graft venous anastomosis. In other words, AVG required fewer interventions before successful cannulation but more interventions after successful use.
The clinical decision about the optimal access choice in a patient dialyzing with a CVC should consider the anticipated access patency, the frequency of interventions to maintain access patency for dialysis, and the patient's life expectancy.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Kapoian T, Sherman RA. A brief history of vascular access for hemodialysis: An unfinished story. Semin Nephrol 1997;17:239-45.
Enzler MA, Rajmon T, Lachat M, Largiadèr F. Long-term function of vascular access for hemodialysis. Clin Transplant 1996;10:511-5.
Coburn MC, Carney WI Jr. Comparison of basilic vein and polytetrafluoroethylene for brachial arteriovenous fistula. J Vasc Surg 1994;20:896-902.
Gibson KD, Caps MT, Kohler TR, Hatsukami TS, Gillen DL, Aldassy M, et al
. Assessment of a policy to reduce placement of prosthetic hemodialysis access. Kidney Int 2001;59:2335-45.
Mosquera D. Regarding “Vascular access survival and incidence of revisions: A comparison of prosthetic grafts, simple autogenous fistulas, and venous transposition fistulas from the United States Renal Data System Dialysis Morbidity and Mortality Study”. J Vasc Surg 2003;37:238-9.
Sorom AJ, Hughes CB, McCarty JT, Jenson BM, Prieto M, Pannenton JM, et al
. Prospective, randomized evaluation of a cuffed e-PTFE graft for hemodialysis vascular access. Surgery 2002;132:135-40.
Elliott MP, Gazzaniga AB, Thomas JM, Haiduc NJ, Rosen SM. Use of expanded polytetrafluoroethylene grafts for vascular access in hemodialysis: Laboratory and clinical evaluation. Am Surg 1977;43:455-9.
Won T, Min SK, Jang JW, Choi SH, Choi KB, Han JJ, et al
. Early result of arteriovenous graft with deep forearm veins as an outflow in hemodialysis patients. Ann Vasc Surg 2002;16:501-4.
Fan PY, Schwab SJ. Vascular access: Concepts for the 1990s. J Am Soc Nephrol 1992;3:1-1.
Applebaum H, Shashikumar VL, Somers LA, Baluarte HJ, Gruskin AB, Grossman M, et al
. Improved hemodialysis access in children. J Pediatr Surg 1980;15:764-9.
Khadra MH, Dwyer AJ, Thompson JF. Advantages of polytetrafluoroethylene arteriovenous loops in the thigh for hemodialysis access. Am J Surg 1997;173:280-3.
Tashjian DB, Lipkowitz GS, Madden RL, Kaufman JL, Rhee SW, Berman J, et al
. Safety and efficacy of femoral-based hemodialysis access grafts. J Vasc Surg 2002;35:691-3.
Salimi J. Patency rate and complications of vascular access grafts for hemodialysis in lower extremities. Saudi J Kidney Dis Transpl 2008;19:929-32.
] [Full text]
Sullivan KL, Besarab A, Bonn J, Shapiro MJ, Gardiner GA Jr., Moritz MJ. Hemodynamics of failing dialysis grafts. Radiology 1993;186:867-72.
Green LD, Lee DS, Kucey DS. A metaanalysis comparing surgical thrombectomy, mechanical thrombectomy, and pharmacomechanical thrombolysis for thrombosed dialysis grafts. J Vasc Surg 2002;36:939-45.
Beathard GA. Thrombolysis versus surgery for the treatment of thrombosed dialysis access grafts. J Am Soc Nephrol 1995;6:1619-24.
Uflacker R, Rajagopalan PR, Vujic I, Stutley JE. Treatment of thrombosed dialysis access grafts: Randomised trial of surgical thrombectomy versus mechanical thrombectomy with the Amplatz device. J Vasc Interv Radiol 1996;7:185-92.
Fong IW, Capellan JM, Simbul M, Angel J. Infection of arterio-venous fistulas created for chronic haemodialysis. Scand J Infect Dis 1993;25:215-20.
Churchill DN, Taylor DW, Cook RJ, LaPlante P, Barre P, Cartier P, et al
. Canadian hemodialysis morbidity study. Am J Kidney Dis 1992;19:214-34.
Schild AF, Simon S, Prieto J, Raines J. Single-center review of infections associated with 1,574 consecutive vascular access procedures. Vasc Endovascular Surg 2003;37:27-31.
Taylor SM, Eaves GL, Weatherford DA, McAlhany JC Jr., Russell HE, Langan EM 3rd
. Results and complications of arteriovenous access dialysis grafts in the lower extremity: A five year review. Am Surg 1996;62:188-91.
Nassar GM, Ayus JC. Infectious complications of the hemodialysis access. Kidney Int 2001;60:1-3.
Cull JD, Cull DL, Taylor SM, Carsten CG 3rd
, Snyder BA, Youkey JR, et al
. Prosthetic thigh arteriovenous access: Outcome with SVS/AAVS reporting standards. J Vasc Surg 2004;39:381-6.
Malik J, Tuka V, Kasalova Z, Chytilova E, Slavikova M, Clagett P, et al
. Understanding the dialysis access steal syndrome. A review of the etiologies, diagnosis, prevention and treatment strategies. J Vasc Access 2008;9:155-66.
Vogel KM, Martino MA, O'Brien SP, Kerstein MD. Complications of lower extremity arteriovenous grafts in patients with end-stage renal disease. South Med J 2000;93:593-5.
Munda R, First MR, Alexander JW, Linnemann CC Jr., Fidler JP, Kittur D. Polytetrafluoroethylene graft survival in hemodialysis. JAMA 1983;249:219-22.
Palder SB, Kirkman RL, Whittemore AD, Hakim RM, Lazarus JM, Tilney NL. Vascular access for hemodialysis. Patency rates and results of revision. Ann Surg 1985;202:235-9.
Katzman HE, Glickman MH, Schild AF, Fujitani RM, Lawson JH. Multicenter evaluation of the bovine mesenteric vein bioprostheses for hemodialysis access in patients with an earlier failed prosthetic graft. J Am Coll Surg 2005;201:223-30.
Gibson KD, Gillen DL, Caps MT, Kohler TR, Sherrard DJ, Stehman-Breen CO. Vascular access survival and incidence of revisions: A comparison of prosthetic grafts, simple autogenous fistulas, and venous transposition fistulas from the United States Renal Data System Dialysis Morbidity and Mortality Study. J Vasc Surg 2001;34:694-700.
Huber TS, Carter JW, Carter RL, Seeger JM. Patency of autogenous and polytetrafluoroethylene upper extremity arteriovenous hemodialysis accesses: A systematic review. J Vasc Surg 2003;38:1005-11.
Hodges TC, Fillinger MF, Zwolak RM, Walsh DB, Bech F, Cronenwett JL. Longitudinal comparison of dialysis access methods: Risk factors for failure. J Vasc Surg 1997;26:1009-19.
Depner TA. Techniques for prospective detection of venous stenosis. Adv Ren Replace Ther 1994;1:119-30.
Martin LG, Macdonald MJ, Kikeri D, Cotsonis GA, Harker LA, Lumsden AB. Prophylactic angioplasty reduces thrombosis in virgin ePTFE arteriovenous dialysis grafts with greater than 50% stenosis: Subset analysis of a prospectively randomised study. J Vasc Intervent Radiol 1999;10:389-96.
[Figure 1], [Figure 2], [Figure 3], [Figure 4], [Figure 5]
[Table 1], [Table 2], [Table 3]