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E. Continued, but close, observation of the patient with treatment initiated if the
bleeding recurs.
After loss of the above hemoaccess, a new autogenous AVF was available for construction in the right arm, which remained functional until the patient’s demise 3
years later.
Commentary
Question 1
The first order of business is to determine whether the individual has a reversible
condition such as obstructive uropathy, drug-induced acute tubular necrosis, or
another nephrotoxic condition. Commencement of hemoaccess would be unnecessary at this time since the individual has minimal symptoms; however, the degree of
renal insufficiency is sufficient to predict that it will likely be required within several
months to a year. Since some access procedures require several months before they
are usable, an experienced surgical specialist should be contacted to construct the
hemoaccess, if the nephrologist confirms that the individual has chronic progressive
renal insufficiency [1]. [Q1: D]
Urgent or immediate hemodialysis is not indicated and because of the associated
morbidity, catheter placement is contraindicated in the absence of acute renal
failure. Likewise, it is inappropriate to refer directly to the surgical specialist
without determining the cause of the renal insufficiency, whether it is reversible,
and whether the individual should be placed on the eligibility list for transplantation. Simply referring the individual to the nephrologist is not wrong, but the best
option includes the diagnostic evaluation, management of treatable etiologies, and
consideration for hemoaccess assuming that commencement of hemodialysis is
imminent within several months to a year. It is clear that early nephrology consultation is of benefit, from the perspective of directing appropriate therapy [2–5].
Likewise, early consideration of hemoaccess options facilitates preservation of vascular assets and reduces the incidence of catheter placement and the subsequent
morbidities.
Question 2
The complete clinical vascular examination is an important adjunct to surgical
planning and may direct the surgeon to either upper extremity; clearly the nondominant upper extremity is preferred, unless a preferred access option is only
available in the dominant extremity. While reliance on the clinical examination
alone may be accurate in many cases, experience currently suggests that valuable
information is contributed by the non-invasive ultrasound survey [6–9].
While reliable duplex ultrasound (DU) examinations may not be available in all
practice situations, it does provide the “best” option by decreasing the likelihood of
unsuccessful operations while increasing the options for autologous conduit.
Additional information from the duplex examination may reveal proximal vein
occlusion, visible superficial veins which are post-phlebitic, arterial abnormalities
352 Vascular Surgery
(location of the brachial bifurcation, occlusive disease, inadequate palmar arch collateralization, large branch veins, and relative size of the arteries and veins).
An added reason for preoperative DU survey is that the diabetic population is the
group most likely to harbor asymptomatic upper extremity arterial occlusive
disease. It is unknown whether this is the reason, but functional patency of hemoaccess is usually reduced in the diabetic population [8, 10, 11]. In obese patients the
lack of visible superficial veins may be countered by duplex examination; the depth
of the veins precludes clinical identification and may mask prior thromboses. The
depth of an otherwise acceptable vein is an important consideration and may
mandate transposition to a more superficial site. Failure to identify superficial
upper extremity veins on clinical examination is not an acceptable rationale for
commencing access at a lower extremity site; even if no superficial veins are available, a prosthetic graft can usually be constructed between the artery and one of the
deep veins in the upper extremity.
As before, there is still no indication for immediate dialysis, so that placement of
a catheter at the time of the permanent access is not indicated in this clinical scenario. [Q2: C]
Question 3
The list includes all of the usual information needed for proper operative planning.
The goal is to construct the most durable hemoaccess from autogenous tissue.
When acceptable options exist only in the dominant upper extremity, it is selected;
thus, both arms should be studied.
Adequate arterial inflow is essential for the fistula or graft to function properly.
Failure was universal with an arterial diameter <1.6 mm in one study [9]. Although
upper extremity atherosclerotic occlusive disease is uncommon in the arm, diabetics are the group most likely to have diseased arteries, and thus it should be considered for this patient. While all vascular laboratories may not subscribe to this
position, no palpable pulses were described in the core scenario such that some
reassurance is needed regarding adequate arterial flow.
A key function of the preoperative duplex examination is to determine the
acceptability of the superficial vein network of the forearm and arm. In addition to
location and diameter, identification of large branches, occluded segments, scarring, other post-thrombotic changes, and depth of vein below the skin are all critical
to success. Failure was also universal when preoperative DU identified stenotic vein
segments [9]. Vein diameters of less than 2.5–3 mm are generally considered unacceptable, but since there is little data to support this recommendation, the reporting
standards did not incorporate a recommendation for a minimum venous diameter
[7]. Complete evaluation of superficial upper extremity veins should include the
forearm basilic vein [6, 12]. Transposition of the basilic vein is usually necessary
whether in the forearm or upper arm, and any vein that is too deep (greater than
0.5–1.0 cm) may need to be transposed before anastomosis.
Central vein stenoses or occlusions are usually due to prior central vein catheterizations, but the surgeon should also be wary of transvenous wires from implanted
pacemakers or defibrillators [1, 13, 14]. Forty percent of patients with known subclavian vein catheterization had moderate to severe subclavian vein stenoses that
were clinically silent [15].
In the absence of an autogenous option, the surgeon should still be informed
regarding the best location for the first graft. The anatomic variant of a high
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brachial bifurcation occurs in ~10 percent of individuals. This anatomic variant
may preclude placement of a prosthetic graft at a given site, but should have little
adverse effect on an autogenous AVF.
Routine evaluation of the lower extremity is unnecessary, but may be considered
when upper extremity sites have been completely exhausted. [Q3: E]
Question 4
This is a complex issue and the correct answer [Q4: E] is derived from a combination
of experience and the recommendations of the United States Kidney Dialysis
Outcomes Quality Initiative (K-DOQI). The best answer is a combination of the
“best” choices summarized from the principles of all autogenous, most distal, nondominant extremity. Thus, since almost all options are really open for this individual, the non-dominant, radiocephalic AVF is the best first choice; a potential
collateral benefit is communication with (and arterialization of) the proximal basilic
vein. Recognition of problems causing failure to mature are the major impediment
to wider utilization of this modality [1, 8–10, 16]. Failure to mature a forearm AVF
may occur in 34–53 percent, and may be less attractive in the elderly, the diabetic,
and female patients [8, 9].
The proximal options of brachial and cephalic anastomoses and transpositions
have experienced a higher incidence of arterial steal and ignore the basic principle
of progression from distal to proximal [1]. The forearm loop graft was equated with
the proximal brachial transposition by K-DOQI, but current initiatives more
emphatically encourage autogenous fistula [5, 16].
Catheter access is to be avoided if at all possible, and is clearly not indicated in
this situation; multiple autogenous options are available and commencement of
dialysis is not emergent [4, 5, 13, 14].
A left radiocephalic AVF serves the dual purpose of increasing lifetime site
options, and allows the distal AVF to develop more proximal veins for subsequent
autogenous hemoaccess options. A forearm vein transposition has been touted as a
better option than the radiocephalic AVF but this option was not available, even in
the dominant extremity, because of post-thrombotic changes [12, 17].
Question 5
Although this is a common clinical question, informed decisions are difficult since
there is a paucity of concrete data. There is little data to support any course of action,
and the correct answer is based upon opinion [1]. [Q5: C] Clearly a healed wound, a
palpable thrill, and unobstructed flow are essential. Two weeks is generally considered early for an AVF, and the minimum recommended interval is 6–8 weeks. For
prosthetic grafts, 2–3 weeks is usually satisfactory, as long as the edema has resolved
sufficiently to identify the outline of the graft. Since the functional patency is so low,
a prosthetic AV graft should not be inserted until dialysis is imminent [1].
A period of 6–8 weeks is an arbitrary interval often used in practice and supported by K-DOQI. However, if at all possible, a longer interval is preferable, since a
matured access is more likely to provide durable function.
A large branch vein within 5 cm of the arteriovenous anastomosis can prevent
maturation, by diversion and diffusion of fistula flow and should be ligated [9].
Thickening of the wall is one of the few indicators of arterialization in the conduit
walls and would therefore be desirable, but there is no data to support this course of
354 Vascular Surgery
action, or to guide the obvious question of how thick? In reality, the progression of
the individual’s renal disease will likely be the best guide. If early referral can be
achieved, urgent commencement of dialysis becomes a moot question and the
hemoaccess is ready for use when the time arrives [1].
Question 6
The best option again emphasizes the principles of most distal site, autogenous if
possible, and in this instance the recruitment of additional vein collaterals from the
long-standing prior left radiocephalic AVF [17, 18]. [Q6: D] The initial DU examination specifically noted the communication from the cephalic feeding the basilic
system; the proximal forearm basilic has a good size and does not exhibit postthrombotic changes from this point into its termination in the brachial veins. Thus,
the transposition of the proximal basilic vein, which may already be arterialized, is
the preferred choice [17, 18]. The arterial inflow for this may be the proximal
forearm radial artery if the vein length is satisfactory; if not the high bifurcation
would still make the inflow from the radial the best choice. Even though the diameter of the artery would be less than the usual brachial diameter, this should not
present a problem for construction of an autogenous fistula.
The brachial arterial variant would compromise the inflow to a left forearm loop
prosthetic graft and even a brachial to axillary prosthetic graft in the arm.
The right forearm loop graft would be an acceptable alternative, except that there
are good autogenous alternatives bilaterally. It moves the access to the dominant
upper extremity and fails to take advantage of the previously arterialized proximal
venous channels.
Any right forearm transposition is inappropriate because both veins have evidence of prior thrombosis.
Central catheter access is to be avoided if at all possible. Multiple autogenous
options are available and dialysis can be maintained in the interval with the existing, but poorly functioning left radiocephalic AVF. By mobilizing a proximal basilic
vein segment that has already been exposed to arterialized fistula flow, the time for
maturation may be reduced [1]. The arm will need to be observed for possible arterial steal, in which case the failing AVF may need to be sacrificed and a hemoaccess
catheter inserted until the new left radiobasilic transposition has matured satisfactorily [13].
Questions 7 and 8
The presence of subclavian vein electrodes in the subclavian vein is the inciting
factor for subclavian vein thrombosis or stenosis whether for pacing or defibrillation. [Q7: E] Symptoms from acute subclavian vein thrombosis are often expressed
for only a short time in patients without an arteriovenous fistula. Edema will be
severely and continuously exacerbated from the additional limb blood flow of the
AVF [13, 14]. Often the edema becomes chronic, and precludes accurate puncture
of an ipsilateral access. Untreated venous hypertension from this combination may
produce the typical symptoms of venous stasis: edema, hyperpigmentation and
even ulceration. Therefore any treatment must include ligation of the access.
Although lymphatic disruption from an infraclavicular pocket incision is possible, this would be so rare as to be remarkable. The electrodes are usually inserted
The Optimal Conduit for Hemodialysis Access 355
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indirectly and do not require surgical exposure of the vein; this reduces the likelihood of injury to the lymphatic channels in the axillary-subclavian vascular sheath.
Localized swelling in the pocket would be a more likely complication than arm
swelling.
There is no evidence for hypercoagulability. Since the electrodes pass through the
SVC, obstruction there is theoretically possible. However, the absence of contralateral upper extremity edema or a swollen head fails to suggest SVC thrombosis.
Replacing the device on the right complicates the issue immeasurably. In addition
to incurring a real risk of SVC obstruction, it also places the remaining (right)
upper extremity at risk for problems with subsequent hemoaccess.
The combination of a high flow AVF with probable subclavian vein obstruction
suggests a rather poor prognosis for the left arm radiobasilic AVF. Thus, investigation of the etiology with a fistulagram and venogram is appropriate. [Q8: D] A DU
should also be obtained, but since central vein visualization is poor it is inadequate
to confirm the suspected diagnosis. Although unlikely, it is entirely possible that the
device has nothing to do with the venous obstruction and that the outflow vein of
the AVF may be stenotic from an intimal hyperplastic response in a different
anatomic location more amenable to a salvage procedure. If this is a subclavian
thrombosis, it may be a good opportunity to consider thrombolysis. However, even
if the vein could be reopened, a subclavian vein angioplasty and/or stent has not
proven a durable solution in this anatomic site [13]. Finally, thrombolysis carries a
small but real risk of intracranial hemorrhage, which would be less acceptable
without a real benefit. Removal of the electrodes would be complicated and risky.
Unfortunately, if the obstruction is not well collateralized, the left arm should be
excluded from future access options [1, 13, 14, 18].
Question 9
The best choice is the right forearm loop prosthetic graft. [Q9: A] Either an internal
jugular (IJ) or femoral catheter site has significant clinical negatives, and fails to
offer a durable solution in the face of numerous better options.
The right brachial to cephalic is an attractive option, which is considered equivalent to the loop graft in the DOQI guidelines; however, as presented in the question,
ligation of the contralateral symptomatic radiobasilic AVF is not accomplished.
More importantly, the two proximal transposition options remain available for construction of subsequent hemoaccess.
Ligation of the left radiobasilic AVF is essential to control the venous obstructive
symptoms. While a jugular vein turn-down would offer preservation of the left
radiobasilic AVF, there is not likely to be sufficient length to reach a non-thrombosed segment of axillary vein. A prosthetic extension to the jugular is another
alternative. Adequate central outflow from the jugular would need to be assured by
venography before further consideration of either option [14, 19].
Question 10
Although there is very little data to provide a clear answer to this clinical problem,
the best choice and DOQI recommendation is prosthetic interposition. [Q10: C] It
preserves a functioning access in someone who has already lost the use of the contralateral upper extremity to venous outflow obstruction [1, 20, 21].
356 Vascular Surgery
Ligation solves the bleeding problem but sacrifices the access. Removal may subsequently be required, but is not essential at this juncture. Revision with primary
closure of the aneurysm is unattractive since the tissues and graft material are
friable and usually destroyed by the repetitive puncture. Close observation is
doomed to fail with a real risk of bleeding and hemorrhage.
Although prosthetic interposition is the appropriate choice, this option is not
without complications. Our own experience identified an increased incidence of
infection, and good material to anastomose may require bypass of lengthy segments
[22]. Recent introduction of the covered stent is an attractive, but unproven option.
Percutaneous access, control of the neck of the pseudoaneurysm, and retention of
hemoaccess function are currently offset by limited clinical data, and high expense
[13, 23].
Comment
The initial use of distal sites, and judicious consumption of the available autogenous assets facilitated construction of several different hemoaccess sites during this
patient’s 14-year odyssey with hemodialysis. Problems such as these are common
and require forethought and ingenuity for successful cumulative function and minimization of major complications.
References
1. NKF-K/DOQI Clinical Practice Guidelines for Vascular Access: Update 2000. Am J Kidney Dis
2001:37:S137–81.
2. Stack AG. Impact of timing of nephrology referral and pre-ESRD care on mortality risk among new
ESRD patients in the United States. Am J Kidney Dis 2003:41:310–18.
3. Khan IH. Co-morbidity: the major challenge for survival and quality of life in end stage renal disease.
Nephrol Dial Transplant 1998:13:S1 76–9.
4. Powe NR. Early referral in chronic kidney disease: an enormous opportunity for prevention. Am J
Kidney Dis 2003:41:505–7.
5. Pisoni RL, Young EW, Dykstra DM, Greenwood RN, Hecking E, Gillespie B, et al. Vascular access use
in Europe and the United States: results from the DOPPS. Kidney Int 2002:61:305–16.
6. Silva MB, Hobson RW, Pappas PJ, Jamil Z, Araki CT, Goldberg MC, et al. A strategy for increasing
use of autogenous hemodialysis access procedures: impact of preoperative noninvasive evaluation. J
Vasc Surg 1998;27:302–8.
7. Sidawy AN, Gray R, Besarab A, Henry M, Ascher E, Silva M, et al. Recommended standards for
reports dealing with arteriovenous hemodialysis accesses. J Vasc Surg 2002;35:603–10.
8. Miller PE, Tolwani A, Luscy CP, Deierhoi MH, Bailey R, Redden DT, Allon M. Predictors of adequacy
of arteriovenous fistulas in hemodialysis patients. Kidney Int 1999;56:275–80.
9. Wong V, Ward R, Taylor J, Selvakumar S, How TV, Bakran A. Factors associated with early failure of
arteriovenous fistulae for haemodialysis access. Eur J Vasc Endovasc Surg 1996;12:207–13.
10. Hodges TC, Fillinger MF, Zwolek RM, Walsh DB, Bech F, Cronenwett JL. Longitudinal comparison of
dialysis access methods: risk factors for failure. J Vasc Surg 1997;26:1009–19.
11. Kalman PG, Pope M, Bhola C, Richardson R, Sniderman KW. A practical approach to vascular access
for hemodialysis and predictors of success. J Vasc Surg 1999;30:727–33.
12. Choi HM, Lal BK, Cerveira JJ, Padberg FT, Hobson RW, Pappas PJ. Durability and cumulative functional patency of transposed and non-transposed arterio-venous fistula. In press, J Vasc Surg 2003.
13. Cerveira JJ, Padberg FT, Pappas PJ, Lal BK. Prevention and management of Complications from
hemoaccess. In: Pearce W, Yao J, Matsumura J, editors. Trends in vascular surgery. Chicago, IL:
Greenwood Academic, 2004.
14. Currier CBJ, Widder S, Ali A, Kuusisto E, Sidawy A. Surgical management of subclavian and axillary
vein thrombosis in patients with a functioning arteriovenous fistula. Surgery 1986;100:25–8.
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15. Surratt RS, Picus D, Hicks ME, Darcy MD, Kleinhoffer M, Jendrisak M. The importance of preoperative evaluation of the subclavian vein in dialysis access planning. AJR Am J Roentgenol
1991;156:623–5.
16. 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.
17. Silva M, Hobson RW, Simonian GT, Haser PB, Jamil Z, Padberg FT, et al. Successful autogenous
hemodialysis access placement after prosthetic failure: the impact of non-invasive assessment.
Poster presentation at SVS/AAVS 2000, Toronto, CA.
18. Haser PB, Padberg FT Jr. Complex solutions for hemoaccess. In: Matsumura J, Pearce W, and Yao
JST, editors. Trends in Vascular Surgery, 2003;Ch 33.
19. Puskas JD, Gertler JP. Internal jugular to axillary vein bypass for subclavian vein thrombosis in the
setting of brachial arteriovenous fistula. J Vasc Surg 1994;19:939–42.
20. Raju S. PTFE grafts for hemodialysis access. Techniques for insertion and management of complications. Ann Surg 1987;206:666–73.
21. Ryan SV, Calligaro KD, Sharff J, Dougherty MJ. Management of infected prosthetic dialysis arteriovenous grafts. J Vasc Surg 2004;39:7378.
22. Padberg FT, Lee BC, Curl GR. Hemoaccess site infection. Surg Gynecol Obstet 1992;174:103–8.
23. Lin PH, Johnson CK, Pullium JK, Koffron AJ, Conklin B, Terramani TT, et al. Transluminal stent
graft repair with Wallgraft endoprosthesis in a porcine arteriovenous graft pseudoaneurysm model.
J Vasc Surg 2003;37:175–81.
39. Acute Ischaemia of the Upper Extremity
Following Graft Arteriovenous Fistula
Miltos K. Lazarides and Vasilios D. Tzilalis
A 65-year-old woman with end-stage renal disease and insulin-dependent diabetes was admitted for access construction in order to start haemodialysis. There
was a lack of suitable veins to construct an arteriovenous (AV) fistula, and the
patient underwent placement of a 6-mm polytetrafluoroethylene (PTFE) AV
bridge graft between the brachial artery and the axillary vein in the left arm.
Question 1
Which of the following is the order of preference for placement of a permanent
angioaccess in new patients requiring chronic haemodialysis?
A. (1) A brachio-cephalic AV fistula. (2) A wrist radial-cephalic AV fistula. (3) An
AV PTFE bridge graft or a transposed brachial-basilic AV fistula. (4) A cuffed,
tunnelled central venous catheter.
B. (1) A wrist radial-cephalic AV fistula. (2) A brachio-cephalic AV fistula. (3) An
AV PTFE bridge graft or a transposed brachial-basilic AV fistula.
C. (1) A wrist radial-cephalic AV fistula. (2) A transposed brachial-basilic AV
fistula. (3) A brachio-cephalic AV fistula. (4) An AV PTFE bridge graft.
Question 2
Which of the following statements represent advantages of the autologous AV
fistulas over AV grafts?
A. Excellent long-term patency once established.
B. Lower complication rate.
C. Short lag time from construction to maturation.
D. Easy to correct surgically when thrombosed.
359
360 Vascular Surgery
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Immediately after surgery, the patient complained of numbness of the left hand
with slight pain of the fingers. On examination the left radial pulse, which had existed
previously, was absent, and the fingers were cold and cyanotic. Evaluation of the
patient in the vascular laboratory with forearm Doppler pressure measurement
revealed an index of 0.3. Interestingly the left forearm segmental pressure index was
normalised after manual compression of the graft, while the left radial pulse reappeared with this manoeuvre. The evaluation confirmed an obvious haemodynamic
“steal”. The patient’s condition deteriorated within a few hours; she developed severe,
acute, painful weakness of the hand, wrist-drop, and minimal ability to flex the wrist.
Question 3
Which of the following statements regarding the incidence of steal after proximal
access construction is correct?
A. The incidence of asymptomatic steal after proximal access construction,
detected in the vascular laboratory, is rare.
B. Clinically obvious mild ischaemia after the construction of a proximal AV fistula
occurs in about 10 per cent of cases.
C. Severe ischaemia necessitating surgical correction complicates 2–4 per cent of
patients following a proximal AV fistula.
Question 4
Which of the following are indications for surgical correction of steal after proximal
access construction?
A. Absence of ipsilateral preoperative existed radial pulse.
B. Severe symptoms (rest pain, paralysis, wrist-drop).
C. Abnormal forearm segmental pressure index measurement.
D. Abnormal ipsilateral nerve conduction studies.
E. Reversal of flow in the distal artery in colour-flow duplex imaging.
Urgent surgical correction was performed. Under local anaesthesia, a small
segment of saphenous vein was harvested. The brachial artery was ligated just distal
to the take-off of the graft. A vein bypass was constructed from the brachial artery
4–5 cm proximally to the inflow of the graft to a point distal to ligation (Fig. 39.1).
Complete relief of symptoms occurred immediately postoperatively. The recovery
of the patient was uneventful. She was discharged home on the third postoperative
day with a palpable left radial pulse and a patent AV graft.
Question 5
Which of the following are acceptable corrective options for limb-threatening steal
following proximal access construction?
Acute Ischaemia of the Upper Extremity Following Graft Arteriovenous Fistula 361
a
b
Fig. 39.1. a The operation before the creation of the corrective procedure. b The corrective procedure with liga-
tion of the artery just distal to the AV graft take-off and the venous bypass from a point proximal to the inflow to
a point just distal to ligation (DRIL procedure). A, brachial artery; AV, axillary vein; BV, basilic vein; G, arteriovenous PTFE graft; VG, vein graft.
A. Percutaneous transluminal angioplasty.
B. Flow reduction procedures (banding, plication or tapering of the AV fistula).
C. AV fistula closure.
D. The DRIL (distal revascularization interval ligation) procedure.
Commentary
Construction of an AV fistula provides a sufficiently superficial arterialised vein that
can be punctured with ease while its flow is high enough to permit efficient dialysis.
Post-dialysis compression of a matured thick-wall arterialised vein in order to stop
bleeding can be obtained readily and reliably.
The classic first-choice site for an AV fistula construction is between the radial
artery and the cephalic vein at the wrist, as introduced by Brescia et al. [1] in 1966. If
the cephalic vein at the wrist or forearm is not usable, then the next alternative is to
move to the antecubital fossa. The AV fistula can be constructed at this site between
the median cubital vein and the brachial artery. The superficial cephalic vein provides enough length of vein suitable for haemodialysis venipunctures. Alternatively,
if the cephalic vein is not usable, then the brachial artery can be anastomosed to the
basilic vein of the upper arm. However, the latter is situated under the deep fascia in
the arm, and mobilisation and transposition to a subcutaneous new position is
always necessary. When an autologous AV fistula either at the wrist or the elbow
cannot be created, then an AV graft using synthetic material bridging an artery and a
vein in the upper extremity (either forearm or arm) is the next choice. Grafts may be
placed in straight, looped or curved configurations. AV grafts and fistulas are created
in the lower extremity only rarely, as they are prone to infection at this site.
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