The function of permanent vascular access

Juan A. Rodriguez, Luis Armadans, Eugenio Ferrer, Antonio Olmos, Salvador Codina, Jorge Bartolomé, Javier Borrellas and Luis Piera

Hospital General Universitario Vall d'Hebron, Servicio de Nefrologia, Barcelona, Spain

Correspondence and offprint requests to: J. A. Rodriguez, Hospital General de la Vall d'Hebron, Servicio de Nefrologia, Psg. Vall d'Hebron 119–129, E-08035 Barcelona, Spain.



   Abstract
 Top
 Abstract
 Introduction
 Subjects and methods
 Results
 Discussion
 References
 
Background. Complications arising from vascular access (VA) are major causes of morbidity in patients on renal replacement therapy (RRT). They contribute to frustration of health care providers and to high medical cost. To prevent failures in the future it will be helpful to identify the factors that are related to VA malfunction.

Methods. In a retrospective analysis we analysed the types, duration and primary rate of patency of 1033 permanent vascular accesses in 544 consecutive patients established during a 13-year period in a tertiary care hospital. Patient characteristics, incidence, and risk factors related to VA failure were registered. In addition, VA outcomes in patients who started haemodialysis with a catheter and in whom initial VA failure occurred were analysed separately.

Results. Forty-five per cent of patients required a central catheter at the start of HD, but 92% of them were being dialysed with an a-v fistula at the last observation. The total number of complications was 0.24 episodes per patient per year at risk and the rate of thrombosis 0.1. A total of 52% of patients were dialysed throughout the observation period with their initial a-v fistula; 9.3% had more than three episodes of VA failure. The radiocephalic a-v fistula was the VA with the best median duration, exceeding 7 years, but also the type that had the highest initial failure rate, i.e. 25% of patients and 13% of the events. The brachiocephalic a-v fistula was the second most frequent type of VA, with a median duration of function of 3.6 years, in contrast to the humerobasilic a-v fistula, which exceeded 5 years. Average patency of the different types of grafts did not exceed 1 year, with the exception of the autologous saphenous graft with a median duration of function of 1.4 years. Patients with glomerulonephritis had the best function rates for their VA, the median exceeding the duration of the study, whereas in half of the diabetic patients it was less than 1 year. The duration of patency of the VA was twice in patients below age 65 years and in elderly males compared to elderly females. Patients who started HD with a catheter, as well as those with initial VA failure, had a higher rate of VA failure in the subsequent course on RRT.

Conclusion. The radiocephalic and the humerobasilic a-v fistulae are the two types of VA with the longest duration of function, although a high rate of initial failure is seen with the radiocephalic a-v fistula. Age, female gender, presence of diabetic nephropathy, start of dialysis with a catheter, and failure to wait for initial maturation of the VA are risk factors, and account for the majority of VA failures during RRT.

Keywords: end-stage renal disease; haemodialysis; renal replacement therapy; vascular access



   Introduction
 Top
 Abstract
 Introduction
 Subjects and methods
 Results
 Discussion
 References
 
Introduction of haemodialysis (HD) as routine treatment for end-stage renal disease (ESRD) made it necessary to find a simple form of repeated access to the vascular system. It was only after the introduction of external silastic canulae by Quinton and Scribner in 1960 that extracorporeal treatment could be established [1]. Several years later, Brescia and Cimino [2] devised the arteriovenous (a-v) fistula, which overcame the limitations of frequent infections and thrombosis. In the 1970s, implantation of grafts was introduced [35], which permitted renal replacement therapy (RRT) in patients devoid of venous vessels.

This rapid progress of innovations in vascular access (VA) has not continued at the same rate as in the first decade of haemodialysis. Contributions in recent years were not paralleled by improvements in results and in quality of life. Currently, complications of vascular access, i.e. dysfunction, thrombosis, or infection are a major cause of hospital admission. They affect the quality of life. For this there are objective reasons (they make it difficult to administer sufficient dose of dialysis) and subjective ones (anxiety because of uncertainty about correct functioning). Furthermore they give rise to frustration in health care personnel [68]. Recently, repeated VA failure has been identified as a risk factor for mortality [9]. Finally, VA failure causes high economical costs, accounting for up to one-third of ESRD expenditure [10].

The radiocephalic a-v fistula is the preferred VA, because of its low complication rates, its long survival, and its ease of puncture once it has matured [1113]. Nevertheless, its establishment on the wrist or in the tabaquière anatomique (anatomical snuffbox) of the non-dominant arm is potentially inconvenient for two reasons (i) 4–8 weeks are necessary until the venous wall has arterialized, and (ii) a high rate, 8–30%, of initial failure or insufficient development is observed, necessitating the use of other modalities of VA [14]. Recently, a-v fistulae higher up in the forearm and on the upper arm have been put forward as acceptable alternatives. Some studies have documented primary patency rates, >80%, in the first 2 years of observation [15], but there is no information on the long-term outcome for this type of a-v fistula.

The second mode of permanent VA are grafts, the use of which has increased in recent years, and in numerous centres it is today the most frequently used type of VA [16]. This tendency has been related to recent demographic changes in the HD population, the scarcity of transplants with the consecutive increased time on HD treatment, and increased comorbidity of patients beginning RRT. In fact the median age of incident patients is actually around 60 years, more than half of the patients have at least two comorbid conditions, and 20–40% are diabetic—all factors that could affect the success of the VA [10,17]. On top of this, patients are not infrequently referred to the nephrologists in the terminal stages of renal failure or during an episode of acute deterioration of pre-existing renal failure. In these circumstance it is frequently impossible to create a VA in time [18].

It is of obvious interest to the nephrologists to identify the different problems related to the VA and to improve results by consensus. With this in mind, we performed the present retrospective study with the following aims: (i) to assess the relative proportions of the different modalities of VA and the respective duration of their function, (ii) to analyse the clinical and demographic factors associated with VA failure, and (iii) to verify whether absence of a functioning VA at the time when HD is started and/or initial failure of the VA affects the results of long-term VA.



   Subjects and methods
 Top
 Abstract
 Introduction
 Subjects and methods
 Results
 Discussion
 References
 
We performed a retrospective study on all patients attending the renal service of the University Hospital Valle de Hebrón of Barcelona who received a VA for chronic HD treatment between 1 January 1985 and 31 December 1997. The hospital is a tertiary care hospital with a catchment area of 800000 inhabitants. We sampled and analysed the following items: demographic characteristics of the patients, primary renal disease, the site of VA, and duration of function. End-point was the date when the VA was no longer regularly used either because of change of treatment modality (CAPD or renal transplantation), change of residence, death, complications, i.e. dysfunction or thrombosis, or end of the study period (31.12.1997). For each episode, the time interval from creation of the VA to intervention was calculated. Dysfunction related to any type of complication, other than thrombosis, that necessitated any type of intervention. As VA we considered only a-v fistulae or grafts, either autologous or heterologous; permanent catheters were not considered a VA, except when all possibilities of access to the vascular system had been exhausted.

Primary renal disease was categorized as glomerular, interstitial (mostly ascending infection), vascular (nephroangiosclerosic or ischaemic), cystic (ADPKD), or diabetic nephropathy. The designation `others' includes different systemic diseases, particularly SLE and vasculitis.

We analysed clinical and demographic characteristics of patients who started HD treatment using a catheter and compared them with patients who at that moment had a mature VA. We also studied whether there were differences in the total number of VA in the two populations in the course of HD treatment. Similarly, we compared the patients with an initial failure of the primary VA or failure of adequate development of the VA with those patients in whom the VA matured normally.

Every patient who needs a VA is examined in our hospital by a vascular surgeon who assesses, as the first option, the possibility of creating a radiocephalic a-v fistula in the upper extremity of the non-dominant arm. If this VA fails, we tend to place a similar VA on the opposite arm. In cases of failure we systematically try to place new a-v fistulae in the upper forearm or the upper arm in the following order: brachiocephalic (BC) and humerobasilic (HB) with subsequent transposition. Generally, implantation of grafts is not considered unless all possibilities of a-v fistulae in both extremities have been exhausted.

Statistical analysis
Using descriptive statistics, we analysed all patients and separately analysed all accesses. The {chi}2 test was used to assess associations between qualitative variables. Student's t-test was used for group comparisons. To assess the association between the number of VA in a given patient and the type of initial vascular access (catheter or a-v fistula) the {chi}2 test for trend was used. To assess time to access failure, the Kaplan–Meier-method was used. To study the association between this time interval and potential risk factors, the log-rank-test was used. To estimate reasons for the incidence of VA failures, proportional hazards regression models were used. To evaluate the association between failure of the initial a-v fistula and potential risk factors, odds ratios were tested using the {chi}2 test. To identify independent predictors of initial VA failure, the multiple regression technique was used with a model that included variables consecutively into the model if their log-likelihood ratios were significant by {chi}2 test. To evaluate the association between numbers of VA in a given patient and initial VA failure the chi-square test for linear trends was used. Calculations were carried out using SPSS for Windows, Release 6.0, (SPSS Inc., Chicago, IL, 1993).



   Results
 Top
 Abstract
 Introduction
 Subjects and methods
 Results
 Discussion
 References
 
The essential characteristics of the study group are given in Table 1Go. The sample of 544 patients had a mean age of 56.2 years (range 17–82). The male/female ratio was 1.7. Patients suffered from different primary renal diseases (see Table 1Go), and overall follow-up time was 2532.8 patient years on treatment.


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Table 1. Characteristics of the patient population (n=544)
 
Type of vascular access
Out of the total of 1033 VA created, 899 (87%) were native a-v fistulae, of which 502 remained patent at the end of the study. At that time, 92% of patients were dialysed using this type of VA (Table 2Go). The radiocephalic fistula is the type most often created and is the type of VA most frequently used (64.5% of patients). Slightly more than 25% of the patients were dialysed using a brachiocephalic fistula and less than 5% using a humerobasilic fistula.


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Table 2. Types of vascular access
 
One hundred and thirty-four grafts were implanted (13%). Of these 47 were autologous saphenous grafts (three on the left extremity) and 87 were PTFE grafts (10 on the left extremity). At the end of the study, only 38 grafts (7%) had remained patent, 35 on the left and only three on the right upper arm. Although PTFE grafts were used twice as frequently as autologous grafts, the saphenous vein was used by most patients (3.2%) in preference to heterologous grafts in a similar location.

During the study period, 456 patients (84%) used only native a-v fistulae as permanent VA; in 75 (14%) was it necessary to resort to alternative a-v fistulae or grafts, whilst only 13 patients were dialysed with grafts exclusively. In three patients, complete obliteration of accessible vessels necessitated treatment with a central catheter (two cases) or PD (one patient).

Number of required accesses per patient
Out of the total number of patients in this study, 286 (52.5%) required creation of only a single VA, and no complication whatsoever of the VA was present during the time of treatment. Of the remaining cases, 141 patients required two VAs, 66 patients three VAs, and 51 patients, i.e. 9.3%, four VAs or more. The mean age of the latter group (27 males) was 57.2 years compared to 55.8 years in the other patients (NS). In the patients with higher numbers of VA failures, no significant relation to the type of primary renal disease was noted.

Complications
Table 3Go lists the complications encountered. On 546 occasions, the VA was complication-free until the end of the study, whereas on 489 occasions some type of intervention was required. The rate of complications was 0.24 per patient and year at risk. Most interventions were associated with fistula dysfunction (51%), most frequently insufficient development of the VA, i.e. in one-quarter of the cases. The other interventions concerned repair for episodes of VA thrombosis, i.e. 0.1 episodes per patient and year at risk. The mechanism causing thrombosis could not be determined in the majority of patients; technical complications were involved only in 8%.


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Table 3. Breakdown of 489 complications
 
Vascular access survival
Figures 1 and 2GoGo give the actuarial survival curves for different types of vascular access; obviously, a-v fistulae have longer survivals than grafts.



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Fig. 1. Actuarial curve of primary patency of different modalities of a-v fistulae. HB, humerobasilic; BC, brachiocephalic; RC, radiocephalic.

 


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Fig. 2. Actuarial rate of primary patency of different types of grafts. SF HC, saphenous humerocephalic, PT HC, PTFE humerocephalic; PT HB, PTFE humerobasilic.

 
The rate of primary patency of radiocephalic a-v fistulae was 77% at 3 months and 72% at 6 months. In contrast, in other types of VA the percentage is almost 10% higher, with the exception of PTFE grafts of the forearm where abnormal function rate of only 50% was noted. The lesser function rate of radiocephalic a-v fistulae is due to the fact that primary malfunction is seen in 15%. The rate patency of radiocephalic a-v fistulae, once the fistula has developed sufficiently to permit at least one puncture, rises to 85% in the first and to 80% in the second year postoperatively. At any given time, the rate of patency of radiocephalic a-v fistulae is superior to that of humerocephalic fistulae. The radiocephalic fistula is the type of VA with the highest long-term function rate, i.e. 45% at 10 years and 38% at 12 years respectively. Finally, the humerobasilic a-v fistula yields the best function rates, surpassing the humerocephalic a-v fistula by 5, 18, and 13% after 1, 3 and 5 years respectively.

The survival rates of grafts is comparable with that of a-v fistulae during the first 6 months, with the exception of PTFE forearm grafts, for which the survival rate at that point in time is lower by 50%. After the first 6 months, the function rate of grafts diminishes progressively and at a faster rate with PTFE grafts and with saphenous grafts. Of the latter, more than 40% function at the end of the second year compared to 20% of the PTFE grafts in a similar location.

Table 4Go gives median duration of a-v survival as a function of different variables.


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Table 4. Duration of function of 1033 vascular accesses as a function of different variables
 
Type of VA.
The radiocephalic a-v fistula achieves the best results, i.e. a median duration of function of 7 years, followed by the humerobasilic a-v fistula and the humerocephalic a-v fistula. The duration of grafts is inferior to that of a-v fistulae; median survival of the saphenous forearm grafts exceeds that of the PTFE graft in the same location by a factor of 2 and that of the PTFE humerobasilic graft by a factor of 3.

Age.
In patients aged above 65 years, median survival of the VA is somewhat higher (P<0.03) than in younger individuals.

Gender.
The median duration of VA in males, i.e. 7 years, is three times higher than in females (RR 1.35, 95% confidence interval 1.13–1.61, P<0.012).

Primary renal disease.
In patients with primary glomerular disease, longer duration of VA was noted and more than half of them had a duration exceeding 13 years. ADPKD came second with a median duration of 7 years (RR 1.15, confidence interval 0.8–1.7). Patients with interstitial nephropathy or vascular nephropathy had intermediate durations, whilst in patients with diabetic nephropathy the average duration of function of VA did not exceed 1 year (RR 2.4, confidence interval 1.8–3.2, P<0.001).

Patients with a central catheter as first vascular access
Somewhat less than half of the patients (45%) had to start dialysis using a central catheter because a well-developed a-v fistula was not available (Table 5Go). When this cohort was compared to patients who initially had a functioning a-v fistula it became obvious that patients who required a catheter were significantly older (58.9 vs 55.4, odds ratio 1.7, 95% confidence interval 1.2–2.5, P<0.04). Notable differences were also found according to the type of primary renal disease. Absence of a mature a-v fistula was most frequently seen in patients with vascular or diabetic disease, compared to patients with ADPKD or interstitial disease (P=0.006).


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Table 5. Type of vascular access at beginning of haemodialysis according to patient characteristics
 
Patients who start haemodialysis using a central catheter have more frequent VA failure than patients with a mature fistula. Whereas 61.6% of patients starting dialysis with a functioning VA had not one single episode of VA failure throughout their HD treatment, this proportion was considerably lower, i.e. 41.6% for patients who started HD using a central catheter ({chi}2 for linear trend 28.6, P<0.001). The number of patients with two failures is virtually identical in the two populations. The risk of requiring three or more vascular accesses is almost double amongst patients who start HD treatment using a central catheter.

Patients with initial vascular access failure
Of the 531 patients who received a-v fistulae, the VA did not achieve definite function in 135 cases (121 radiocephalic and 14 humerocephalic a-v fistulae, see Table 6Go). Causes were immediate thrombosis for technical reasons (40 cases, 7.5%) and insufficient maturation to permit puncture (95 patients, 18%). When patients with normal VA development are compared to patients with initial VA failure, one finds a predominance of females amongst the latter (OR 1.67, 95% CI, 1.12–2.49, P<0.01). Half of the patients with diabetic nephropathy had initial failure, whilst approximately 20% of patients with other primary renal diseases had this complication, with no significant differences between the disease categories. Multivariate analysis showed that female gender and diabetic nephropathy are independent predictors of initial VA failure (see Table 7Go).


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Table 6. Initial developments of the a-v fistula according to characteristics
 

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Table 7. Independent risk factors associated with initial a-v fistula failure (multivariate analysis)
 
One notes also that patients who experience normal development of the primary VA have fewer VA failures during the treatment period. More than one-third of the patients with maturation of the initial VA have no VA failure whatsoever during the treatment period, whereas the proportion of patients requiring two, three, or more VAs is twice, thrice, and eight times higher amongst patients who had initial VA failure ({chi}2 for linear trend 179, P<0.001).



   Discussion
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 Abstract
 Introduction
 Subjects and methods
 Results
 Discussion
 References
 
Our approach to the creation of VAs for patients requiring renal replacement therapy is in agreement with the recent NKD-DOQUI guidelines, i.e. an initial effort to create an autologous a-v fistula at a peripheral site, advancing from the distal to the proximal part of the extremity when revisions are required. Grafts are reserved for patients whose venous vascular bed has been exhausted. The above long-term study shows that a strategy designed to maximize the use of native a-v fistulae permits satisfactory use of this form of VA in practically all patients (92%); in no less than 84%, this is the only modality of VA in the entire course of their treatment. We also believe that this strategy resulted in a low incidence of thrombosis, i.e. eight times lower than the average figures reported from the USA and 50% lower than that proposed by the National Kidney Foundation as the future goal [19].

The factors that determine the patency of the VA depend mainly on patient characteristics, surgical skill, and care of staff. It is therefore scarcely surprising that published results differ. Some non-randomized studies report that the duration of function of fistulae and grafts is similar [20], but the majority of reports finds the opposite [6,8,19]. In our study, the patency rate of a-v fistulae is markedly superior to grafts, although detailed statistical analysis is not possible, because creation of an a-v fistula had priority over a graft.

The radiocephalic a-v fistula was tried first, as generally accepted, in view of its technical advantages for implantation and high function rate [13,19]. In this study, the rates of patency of this type of VA are similar to reports in literature, i.e. 90 and 80% in the first and second year respectively. Long-term observations show that more than half of our patients have a patent fistula at more than 7 years post-operatively and 36% more than 12 years post-operatively. Undoubtedly, the radiocephalic approach has the inconvenience that there is a high initial failure rate. Studies published since the late 60s report a primary failure rate between 9 and 30%; in our study it was 25%, a figure which undoubtedly could be improved with new non-invasive techniques that allow the estimation of calibre and flow of vessels before creation of a fistula and to predict the potential of adequate vessel maturation [21].

The brachiocephalic a-v fistula is the preferred type of VA, if the radiocephalic approach fails. It should be created as the primary fistula if adequate vessels are not available, which is frequently the case in diabetic patients. Four-year permeability rates of 80% have been reported [15]. In our study, survival of the brachiocephalic a-v fistula was lower than that of the radiocephalic: slightly more than one-half of patients have patent fistulae after 4 years and one-third after more than 8 years.

If the cephalic vein cannot be used, one has the alternatives of implantation of a forearm graft and creation of a humerobasilic a-v fistula. Selection of this type of VA has certain technical disadvantages, i.e. the basilic vein must be superficialized to make it easily accessible for puncture. The technique can also cause steal phenomenon and local oedema. On the other hand it has certain advantages. Since the basilic vein is not visible, it has usually not been damaged by cannulations prior to end-stage renal disease. Published information on patency rates gives values of 75% at 8 years [22]. In our study, the patency rate of humerobasilical a-v fistulae resembles that of the radiocephalic (excluding early failure) and is superior to the brachiocephalic a-v fistula.

As in other studies, age, female gender, and diabetes are the principal factors that determine the long-term function of VA [23,24]. More than 50% of patients keep their initial VA over 13 years of follow-up. We believe that such remarkable function rates in patients with glomerular disease are due to several facts: (i) patients with this disease are referred to the nephrologist early; (ii) the disease course is progressive but predictable; and (iii) the disease affects relatively young individuals: all these are points that contribute to adequate timing and early creation of a VA. ADPKD also has a long disease course, but the results of VA are not so good as in glomerular disease, presumably because of the higher age of the patients. The short duration of functional VA in patients with interstitial nephropathy could be explained by the preponderance of the female sex, which is an independent risk factor for VA failure.

Recently, Woods and Port emphasized the importance to define the factors which are involved in the failure of the first VA, since such predisposing factors could predict future failures and poor overall results as well [22,25]. Our study is in line with this recommendation and shows that more than two-thirds of patients in whom the first VA developed successfully did not have any subsequent VA failure, whereas initial failure increased the risk of subsequent failure by a factor of 2–8. Again, female gender and presence of diabetes were risk factors related to VA failure (Table 7Go); in female diabetic patients, the risk was elevated by a factor of 6. Another factor predisposing to multiple episodes of VA failure is absence of a mature VA at the start of haemodialysis [26]. In almost half of the patients of our study, treatment had to be started with a central catheter. In this subgroup, the risk of future VA failure was double that of patients starting dialysis with a mature VA.

An ideal VA must provide sufficient flow for HD and cause minimal complications. This ideal type of VA is not available, but autologous a-v fistulae come closest to satisfying this requirement. In order to minimize morbidity and cost, a multidisciplinary effort should be directed at the goal that all patients starting HD treatment have a VA ready to be punctured.



   Acknowledgments
 
We thank Dr Ritz for suggestions and translation from Spanish to English.



   References
 Top
 Abstract
 Introduction
 Subjects and methods
 Results
 Discussion
 References
 

  1. Quinton WE, WE, Dillard DH, Scribner BH. Cannulation of blood vessels for prolonged hemodialysis. Trans Am Soc Artif Intern Organs 1960; 6: 104–113[ISI][Medline]
  2. Brescia MJ, Cimino JE, Appel K, Hurwich BJ. Chronic hemodialysis using venipuncture and a surgically created arteriovenous fistula. N Engl J Med 1996; 275: 1089–1092
  3. Flores-Izquierdo G, Vivero RR, Exaire E, Chavez AH, Rios JG. Autoinjerto venoso para hemodialysis. Arch Inst Cardiol Mex 1969; 39: 255–266
  4. Dunn I, Frumkin E, Forte R, Raquena R, Levowitz BS. Dacron velour vascular prosthesis for hemodialysis. Proc Clin Dial Transplant Forum 1972; 2: 85
  5. Baker LD, Johnson JM, Goldfarb D. Expanded polytetrafluoroethyl (PTFE) subcutaneous arteriovenous conduit: an improved vascular access for chronic hemodialysis. Trans Soc Artif Intern Organs 1976; 22: 382–3 87
  6. Fan PY, Schawab SJ. Vascular Access: Concepts for the 1990s. J Am Soc Nephrol 1992; 3: 1–11[Abstract]
  7. Himmelfarb J, Saad T. Hemodialysis vascular access: emerging concepts. Curr Opin Nephrol Hypertens 1996 5: 485–491[Medline]
  8. Hakim R, Himmelfarb J. Hemodialysis access failure: A call to action. Kidney Int 1998: 54: 1029–1040[ISI][Medline]
  9. Almeida E, Dias L, Teixeira F, Mil-Homens MC, Pataca I, Martins M. Survival in hemodilysis: is there a role for vascular access? Nephrol Dial Transplant 1997; 12: 852
  10. Feldman HL, Kobin S, Wasserstein A. Hemodialysis vascular access morbidity. J Am Soc Nephrol 1996; 7: 523–535[Abstract]
  11. Kinnaert P, Vereerstraeten P, Taussaint C, Van Geertruydent J. Nine years' experience with internal arteriovenous fistulas for hemodialysis: a study of some factors influencing the results. Br J Surg 1977; 64: 242–246[ISI][Medline]
  12. Reilly DT, Wood RFM, Bell PRF. Prospective study of dialysis fistulas: problem patients and their treatment. Br J Surg 1982; 69: 549–553[ISI][Medline]
  13. Windus DW. Permanent vascular access: A nephrologist's view. Am J Kidney Dis 1993; 21: 457–471[ISI][Medline]
  14. Winset OE, Wolmn FJ. Complications of vascular access for hemodialysis. South Med J 1985; 66: 23–28
  15. Bender MH, Bruininckx CM, Gerlag PG. The brachiocephalic elbow fistula: A useful alternative angioaccess for hemodialysis. J Vasc Surg 1994; 20: 808–813[ISI][Medline]
  16. Kaufmann JL. The decline of autogenous hemodialysis access site. Semin Dial 1995; 8: 59–61[ISI]
  17. US Renal Data System. USRDS 1998 Annual Data Report. National Institutes of Health, National Institute of Diabetes and Digestive and Kidney Diseases. Bethesda, 1998
  18. Obrador GT, Brian GG, Pereira DM. Early referral to the nephrologist and timely initiation of renal replacement therapy: A paradigm shift in the management of patients with renal failure. Am J Kidney Dis 1998; 31: 398–417[ISI][Medline]
  19. Schwab SJ, Besarab A, Beathard G et al. National Kidney Foundation DOQI Clinical Practice Guidelines for Hemodialysis Vascular Access Working Group. Am J Kidney Dis 1997; 30 [Supp 3]: S154–196
  20. Kherlakian GM, Roedersheimer LR, Arbaugh JJ, Newmark KJ, King LR. Comparison of autologous fistula versus expanded polytetrafluoroethylene graft fistula for angioaccess in hemodialysis. Am J Surg 1986; 152: 238–243[ISI][Medline]
  21. Lemson MS, Leunissen KLM, Tordoir JHM, Does pre-operative duplex examination improve patency rates of Brescia–Cimino fistulas? Nephrol Dial Transplant 1998; 13: 1360–1361[ISI][Medline]
  22. Coburn MC, Carney WI. Comparison of basilic vein and polytetrafluoroethylene. J Vasc Surg 1994; 20: 896–904[ISI][Medline]
  23. Feldman HJ, Held PJ, Hutchinson JT, Stoiver E, Hartigan MF, Berlin JA. Hemodialysis vascular access morbidity in the United States. Kidney Int 1993; 43: 1091–1096[ISI][Medline]
  24. Woods JD, Turenne MN, Strawderman RL et al. Vascular access survival among incident hemodialysis patients in the United States. Am J Kidney Dis 1997; 30: 50–57[ISI][Medline]
  25. Woods JD, Port FK. The impact of vascular access for haemodialysis on patient morbidity and mortality. Nephrol Dial Transplant 1997; 12: 657–659[Free Full Text]
  26. Schillinger F, Schillinger D, Montagnac R, Milcent T. Post catheterization vein stenosis in haemodialysis: comparative angiographic study of 50 subclavian and 50 internal jugular accesses. Nephrol Dial Transplant 1991; 6: 722–724[Abstract]
Received for publication: 5. 7.99
Accepted in revised form: 11.10.99