Evaluation of the role of distal revascularization with interval ligation (DRIL) and revision using distal inflow (RUDI) in treatment of dialysis associated steal syndrome

Evaluation of the role of distal revascularization with interval ligation (DRIL) and revision using distal inflow (RUDI) in treatment of dialysis associated steal syndrome

Mohamed M Elwageh, MD(a); Ahmed H Elbarbary, MD(aJ;

Amro M AboRahma, MD(a); MohamedArafa MSdb)

(a) Department of Vascular Surgery, Tanta University.

(b) Department of General Surgery Department, Tanta University.

Objective:  Dialysis-associated steal syndrome (DASS) is a complication that may occur in

>4% of patients with arteriovenous fistula. The best treatment method for this condition is up till now controversial.

Aim of the work:  The purpose of this study was to evaluate two common procedures to treat this condition; Distal Revascularization  with Interval Ligation (DRIL) or Revision Using Distal Inflow (RUDI) aiming at preservation of both the function of the fistula and the limb.

Patients and methods:  Fourteen patients having native brachiocephalic  or brachiobasilic hemodialysis  AV  fistula  complicated  by  dialysis  associated  steal  syndrome  (DASS),  were randomly divided according to treatment method into DRIL and RUDI groups with 7 patients in each group. Patients with proximal or distal arterial disease and those with low-flow steal were excluded  Short term access patency and limb salvage were set as primary endpoints. In all patients great saphenous vein was harvested  from the thigh. Early post-procedural  follow up and mid-term  follow up were after one and three months.

Results:  From November 2011 to March 2013, 14 patients presented with (DASS). In DRIL group  (7 patients),  the mean age  was 49.2 years,  4  females and 4 diabetics  while in RUDI group (7 patients), the mean age was 52.3 years, 5 females and 7 diabetics. All fistulas were brachiocephalic  and  only one  was brachiobasilic  AVF in DRIL group.  All patients in both groups presented with pain, pallor, coldness and cyanosis of the hand  Stage III DASS {rest pain) was present in 2 cases of each group, whereas Stage IV small superficial ulcers were present in 3 vs 4 and digital gangrene in 2 vs. 1 in DRIL vs. RUDI respectively   In group 1 (DRIL) technique; 5 patients (71.4%)  had marked improvement of pain, cyanosis, capillary refill and coldness. Pallor improved in all cases. Distal pulses returned in 4 patients, remained  weak in one patient and failed to return in 2 (28.6%). Closure of the access was necessary in 2 patients due to infection in one and due to risk of limb loss in the other; access patency was (71.4%) and limb salvage was (100%). In RUDI cases, pain, hand coldness, pallor and cyanosis greatly improved in all cases post-operatively. Distal pulses and capillary refill returned and became comparable to the healthy  side in 6 patients  (85 7%). Limb salvage and access patency  were achieved in all cases (100%).

Conclusion:  RUDI  procedure incorporates  most  of the advantages  of other  access  and hand-preserving procedures. In contrast to DRIL procedure, it is the fistula that is placed at risk by ligation and revascularization,  not the native arterial supply to the ischemic  hand  RUDI may become the procedure of choice  for patients with dialysis-associated  steal syndrome after a brachial artery-based arteriovenous fistula.

Key words:  Steal syndrome, DASS, AVfistula, DRIL, RUDI.

Introduction:

Arteriovenous fistulae in the arm are commonly   used  for  hemodialysis   in  end­ stage  renal disease. All fistulae shunt  blood away from the distal arm, and physiological steal (reversed flow in the artery distal to the arteriovenous fistulae) can occur in 70% of radiocephalic fistulae and 90% of brachial artery   based  fistulae.   However,  symptoms of hand ischemia (pain, pallor, cyanosis, paraesthesia,  ulcers or gangrene) only occur inl-2% of radiocephalic fistulae and 5-10% of brachial artery based fistulae.l-5

Any     vascular     disease     that     affects the proximal or distal arteries (e.g. atherosclerosis, vasculitis, Buerger's disease) can reduce flow to cause symptoms. The risk factors for ischemic steal syndrome include diabetes  mellitus,  peripheral  artery  disease, age greater than 60 years, women, upper arm versus lower arm fistulae, multiple operations in  the  same  limb,  and  the  use  of  PTFE grafts.4,6-9  These factors presumably relate to increased or more diffuse arteriosclerosis  of the arteries in the forearm and hand, and poor development  of collaterals.lO

Several  techniques   have  been  used  for

managing dialysis associated steal syndrome (DASS)     Figure (1),    including    banding, access ligation, distal revascularization with interval   ligation   (DRIL),ll   revision   using distal  inflow  (RUDI),  and  proximalization of the arterial inflow (PAI).l2 None of these techniques have been proven to be the method of choice. In distal radiocephalic fistulae, simple  ligation  of the distal  radial artery  is often used to eliminate  retrograde flow into the AVF.l3

Patients and methods

Study design: This prospective randomized study was conducted on fourteen patients presented with dialysis associated steal syndrome (DASS) after native brachial artery­ based hemodialysis arteriovenous fistula admitted to vascular surgery unit, department of general surgery, Tanta University Hospitals during the period from November 2011 to March 2013. Patients were divided randomly between 2 groups : group one 7 patients who

had distal revascularization interval ligation (DRIL) technique;  and group two 7 patients who had revision using distal inflow (RUDI) technique. Randomization was done by allocation of cases presented by odd numbers to  group  1  (DRIL)  and cases  presented  by even numbers to group 2 (RUDI).

Inclusion criteria:

•    Dialysis associated steal syndrome presented by rest pain, ulcer, necrosis or gangrene due to native brachiocephalic or brachiobasilic dialysis AV fistula.

Exclusion criteria:

•      Patients   with    proximal    or   distal arterial disease.

•       Patients with low-flow steal syndrome.

Study endpoints:

•     Short term access patency and limb salvage.

Before participation in the study a written

informed  consent  was taken  from  each patient according to the ethical committee arrangement measures of the faculty.

Outcome variables: A detailed history including demographic data, continuous medical diseases as diabetes mellitus, hypertension and ischemic heart disease. Duration,  type and site of AV fistula; presenting signs and symptoms as pain, coldness, numbness,trophic changes, necrosis and digital gangrene. Check up of radial and ulnar pulses before and after compressing the anastomotic site to record the change in pulse volume  and force  and  whether  radial  and/ or ulnar pulses return or not. The degree of ischemic steal was recorded in each patient according to the following Table(l).

Duplex   study   was   performed   for   the

affected limb to evaluate; venous outflow volume,  state  of  arterial  tree  in the  upper limb proximal and distal to the fistula and augmentation of flow after compression of anastomotic site. CT arteriography  of the affected  arm  was  done  when  proximal  or distal   arterial   lesions   were   suspected   by duplex or when no return of radial or ulnar pulses after compression of anastomotic site.

Operative procedure: Under general anaesthesia    a   skin    incision    was    done just  above  the  cubital  fossa  for  proximal

anastomosis  and another one in the forearm for distal (radial or ulnar) anastomosis, skeletonization of brachial artery and venous side  of  fistula  from  proximal  incision  and distal arteries(radial or ulnar) from distal incision. (1)  In DRIL procedure,  Figure (2) the brachial artery just below the fistula was ligated to prevent reversal of flow in the distal artery, and a bypass graft was placed from the brachial artery well above the fistula (3-5cm) to the dominant artery (radial or ulnar) distal to the fistula. (2) In RUDI, Figure (2), ligation of the venous limb of the fistula at its origin and creation  of a bypass  to the fistula from one ofthe more distal forearm arteries, distal anastomosis  first then proximal  anastomosis was done. In all patients the graft was from the great saphenous  vein harvested from the thigh.

Follow-up:   Patients   were   subjected   to

early clinical follow up and mid-term clinical and duplex follow up after one and three months; to quantify blood flow in fistula and evaluate reversal of blood flow in artery distal to fistula.

Results:

Total number  of patients  in both  groups was 14  with  7 patients  in each group.  The mean age for DRIL group was 49.2 years and that of RUDI group was 52.3 years. In DRIL group  there  were  3  males  and  4  females, while  in  RUDI  group  there  were  2  males and  5 females.  Interval  from  AVF creation to intervention (DRIL or RUDI) had a mean of 13 months (ranging from 0 to 45 months). Hypertension  was  present  in  8  cases  4  in each group,  diabetes  mellitus in  11 cases  4 in group (1) and 7 in group (2). All fistulae were brachiocephalic and only one was brachiobasilic  AVF in group (1). All fistulae were functioning with palpable thrill and audible murmur at time of first examination. Clinical presentation and staging of patients was described in Tables (2,3).

Pain, pallor, cyanosis and coldness were constant features in all patients. Motor and sensory weakness were observed during examination in 5 patients ; 3 in group (1) and

2 in group (2). Radial pulse was not palpable

in 10 cases 5 in each group and weaker than the contra-lateral  palpable radial pulse in the remaining  4 cases.  Compression  on the site of anastomosis augments pulse force in the weak group and rendered the radial pulse palpable  in  10  cases  (71.43%)  this  finding was also confirmed by Doppler examination.

Preoperative  CT  angiography  was  done

in 4 cases to confirm or exclude associated concomitant arterial occlusive disease suspected   by   previous   duplex   study.   No arterial  stenosis proximal  or distal  was revealed  in these  cases.  Two more  patients who   did   not   yet   start   dialysis   did   not undergo angiography because of concerns of nephrotoxicity.

Post-operative outcome:

I. Clinical  outcome Table (3): In patients who  had  correction  of  steal  syndrome  by DRIL  technique;   marked   improvement   of pain,  cyanosis,  capillary  refill and  coldness was observed in 5 patients (71.4%), the other

2 (28.6%)  had no or minimal improvement.

Hand pallor improved in all cases, however in

2 cases (28.6%) cyanosis was reported during dialysis sessions. Distal pulses returned in four patients, remained weak in one patient and failed to return  in the remaining  2 (28.6%). In 2 patients  (stage  IV)(28.6%)  amputation of gangrenous digits was performed without significant  wound  complications.  A closure of  the  access  was  necessary  in  2  patients due to infection in one and due to failure of improvement  of  manifestations  and  risk  of limb loss in the other; so access patency here was  only  (71.4%)  trying  for  limb  salvage which was (100%).

In  cases  managed  by  RUDI  technique the  results  were  much  better  where  pain, hand coldness, pallor and cyanosis greatly improved in all cases post-operatively. Distal pulses returned and became comparable to the healthy side in 6 patients (85. 7%) and weaker than the healthy side in one patient, capillary refill improved to normal in 6 patients (85.7%) and delayed in 1 patient (14.3%). No early postoperative   complications   happened.   In one patient (stage IV)(14.3%) an amputation of gangrenous distal two phalanges of medial

3 fingers of left hand was performed without

wound  complications. Limb  salvage  and access   patency   were   achieved   in  all  cases (100%).

II.  Clinical  follow-up: The  mean  follow­ up period was 75 days; range (35-90 days). Amputation of gangrenous digits was performed for stage IV patients in both groups without    significant   wound    complications and healing  of stumps  occurred  after a mean period of 40 days in DRIL group and 43 days in RUDI group. Healing of ulcers and trophic lesions Figures (4,5) was observed in all cases after  a mean  period  of 29 days  in group  (1) and  21 days in group  (2); except  in one case of group (1) in which absence of healing after

3 weeks  together  with  lack  of improvement

of symptoms and signs  necessitated ligation of fistula.

III. Duplex  results : There was a reduction in   mean   venous   (fistula)   outflow   velocity and mean vein diameter in face of improved proximal  (brachial) and distal artery flow velocity  and wave patterns.

Discussion:

Storey  et al. in  1969  first described steal syndrome associated  with  vascular  accesses for  dialysis,  secondary to a Brescia-Cimino fistula   between  the   radial   artery   and  the distal cephalic vein.l4,15 In this type of fistula approximately  75%   of  the   blood   flow   is supplied by  the  proximal   radial  artery,  but

25%  comes  from  a  patent  ulnar  artery  via the   distal  radial   artery   and  palmar   arch.l6

In elbow  fistulae, the periarticular arterial collaterals have the same  impact. 1

Physiologic steal (stage I) with retrograde flow  in the  arm  artery  distal  to the  fistula  is common after the creation of a fistula because of the  low vascular resistance of the venous outflow   compared to  the  higher   peripheral arterial        resistance.l7,18            The                development and  dilatation of collateral  arteries  from  the proximal inflow artery over months following creation   of  the  fistula  increases blood  flow to  the   handl7   compensating  for   enhanced systolic  AV  flow   and   also   for   diastolic retrograde inflow  into the  fistula.l8  Another contributing factor  is  hypotension which  is a common  event  during  a dialysis  treatment

which tends to lower venous  return, reducing cardiac output and lowering the perfusion pressure  in the fistula outflow artery and collaterals that  supply  the handl8  and may subsequently result in symptoms of steal only during periods  of hypoperfusion related to hypotensionl9 (stage II).

Pathological      steal      with      continuous

ischemic symptoms can occur  because  of proximal   inflow  disease,  reduced   collateral flow to the hand, or distal outflow obstruction. These all disturb the normal compensatory mechanisms      (peripheral      vasodilatation and increased collateral  flow) to preserve perfusion to the distal arm.lO Arterial stenosis upstream  of the anastomosis prevents the necessary flow increase  in the feeding  artery; severe  peripheral arterial occlusive disease (PAOD)  or vasculitis enhance  the resistance of  distal  arteries  and  simultaneously impair the  function  of  natural  collaterals.l8 Instead of  a  steal   syndrome  stage   I  (also   named steal phenomenon) or II during  dialysis  or exertion, the  more   advanced   stages   III  or IV develop, with clinical signs of peripheral ischaemia. Under these conditions, during diastole virtually all blood coming from the collaterals is drained  into the access.20

Several diagnostic tools,  including measurement   of   systolic    pressure    index (SPI), finger-arm pressure  index, digital plethysmography with  oxymetry,  and pulsed Doppler,  have  been proposed to evaluate hemodynamic parameters distal to AVF to identify   patients   at   risk   for   development of     symptomatic     steal     syndrome.5,21-24

Although  these    techniques   can   detect   a decrease   in  pressure   and  digital   perfusion that  improves  after  compression of the AVF, they  are  poor  predictors of  the  risk of  hand ischemia.25 Thus careful clinical examination is  important  to   determine   the   severity  of symptoms  and   thus   the   need   for   prompt surgical  treatment to avoid the appearance of irreversible neurologic sequelae  or extensive trophic            manifestations that       can                require major  amputation. Appearance of neurologic symptoms can mimic carpal tunnel syndrome, which    can   delay   diagnosis  and   lead   to unwarranted intervention for  decompression

Banding              DRIL               RUDI                 PAl

CephallcV.

Ffstual

Ligation{

r

Figure {1): Several methods tomanage DASS; {DRIL, distal revascularization, interval ligation; RUDI, revision using distal inflow; PAl, proximal arterial inflow graft. 13)

Figures {2,3): 2) above DRIL, below RUDI  3) CT angiography in DASS case with no proximal or distal arterial lesion.

Figures {4,5): A case oftrophic ulcers healed after RUDI

Table 1: Classification of dialysis associated steal syndrome.l

Table 2: Clinical staging of study cases at time of presentation.

Table 3: Clinical examination of the patients before and after management.

of the median nerve.26,27

Pre-operative   duplex  evaluation   is  also not   sufficient   to  establish   the   diagnosis. Retrograde    flow    in   the   brachial    artery just  distal  to  the  fistula  is  detected  in the majority   of   patients   following   proximal access  creation,  indicating  that  the  access consumes  not  only the  antegrade  flow, but also  a portion  of  the collateral  flow  to  the

forearm.l7  However, pre-operative  duplex is

useful in suspecting proximal or distal arterial lesions  as  well as for  measuring  the  radial and ulnar arterial diameters before planning the intervention  to choose the dominant one for  distal  anastomosis   landing.   Moreover, duplex mapping of the great saphenous  vein is required in most patients. Post-operatively, duplex is useful in detecting that the reversed flow has stopped by any of either maneuvers

(DRIL or RUDI), and that antegrade flow is

in-    ams        ur.           ;

Table 4: Duplex  data preoperative and one month postoperative in both groups:

well  established  with  good  distal  perfusion of forearm and hand arteries. Arteriography, whether conventional, CT angiography  or magnetic  resonance  angiography  (MRA)  of the  donor artery  may be helpful  in the  20-

30% of  patients  who  have proximal  inflow

stenosis.   In  those   cases,   compression   of the AV fistula is an additional  maneuver  to visualize the impaired distal vessels.l7

In     the      present     study,     the      clinical presentation                 was       stage     III                     DASS in

2(28.57%) cases of each group, and stage IV

in the remaining  5 patients  (71.43%).  Stage IV  patients  presented  by  either  superficial hand ulcers  and necrosis  which were found in 7 cases; 3 in group (1) and 4 in group (2) or by gangrene  of digits that required  post­ operative  amputation  which was found  in 2 cases in group (1) and one case of group (2). Interval  from  AVF creation  to  intervention (DRIL or RUDI) was a mean of 13 months (ranging from 0 to 45 months). This time may be to some extent long and this might be due to delay in diagnosis, exclusion of associated proximal  and distal arterial lesions, also not all cases of steal are treated  by intervention but   only   when   conservative   methods   of treatment have failed and stages III or IV have been reached.  Haimov et al.20  reported three hand amputations  and one finger amputation and  Redfern  et  ai28 performed  six  digital amputations   due  to  necrosis.  Illig  et  ai29 reported treatment of9 patients with DRIL, 5 with rest pain (stage III) and 4 with (stage IV) active ulceration or gangrene, two had motor dysfunction.  Interval  from  AVF creation  to

a mean  of 1 year. Seven  DRIL procedures were performed with saphenous vein and two with polytetrafluoroethylene.

Two  treatment   methods  had  been  used

in this  current  study, DRIL and RUDI each was used for treatment of 7 cases of DASS. In DRIL group symptoms of steal clearly improved in 5 patients (71.43%), while 2 patients  were  still  suffering  cyanosis   and pain especially during dialysis, infection necessitated ligation of the access in one of them and deterioration of the limb with no attempts of healing of ulcers necessitated ligation of the other. Access patency was 5 cases (71.43%) and limb salvage was (100%) both at 3 months. Ulcer healing occurred in a mean duration of 29 days. Better results were obtained in RUDI group, where all cases had improved, access patency and limb salvage were  (100%),   mean  duration  of  complete ulcer healing was 21 days.

Schanzer  et  al.  in  1988  first  described the   DRIL  procedure. 11   The  same   authors later  reported  their  results  in  23  patients,

noting   complete   resolution   of   symptoms in  19  patients,  one late  amputation,  95.6% two-year   bypass   patency,  and  73.0%  and

45.5%  one-  and  two-year   fistula  patency, respectively.20     In    a   more           recent            study, Schanzer  and Eisenberg treated  42 patients, with        34         (83%)            experiencing complete resolution  of  symptoms.30   Berman  et  ai19 treated 21 cases with DRIL technique, at one year fistula  patency  was  94%,  while  Knox

et aP1 reported  patencies  of  83% at  1 year

and 71% at 3 years in their 52 cases series.

of 69% at 1 year, they managed 28 cases 10 native fistulae and 18 AV grafts.

The DRIL procedure involves ligating the

native vessel just distal to the AV fistula, with revascularization  of the hand via an arterial bypass originating at least 5 em proximal to the fistula. The bypass is thought to help correct the discordance in the resistances of the fistula and  the  distal  vascular  bed by  lengthening the   fistula   and   improving   the   collateral circulation   to   the   distal   vascular   bed.32

However, the main feature  of the procedure

is that it directly prevents the reversal of flow in the  brachial  artery  by ligation  just distal to the fistula.30  The  bypass  ensures  normal flow to the  hand  via an alternate  pathway. DRIL  technique  restores  antegrade  flow to the ischemic limb, eliminates the potential pathway  for  the  steal  mechanism,  and preserves the dialysis access. Ligation of the healthy native (brachial) artery in a relatively ischemic limb is the main drawback of DRIL method, so it leaves the distal arm dependent on a graft for blood supply moreover distal anastomoses   are  technically   more  difficult in patients with diffuse diseases in the distal forearm arteries.8

Attempts to avoid the main disadvantage ofDRIL led Minion et al., in 20058 to describe anothertreatmentmethodforthisclinical entity that maintains the native arterial circulation. RUDI consists of ligating the fistula vein at its origin and re-establishing  inflow to the fistula using a more distal arterial source. The source  consisted  of  the  proximal  radial  or ulnar artery approximately 2 to 3 em distal to the brachial bifurcation. Minion et al8 in their report revised 4 cases ofDASS, the proximal radial artery was used as the supply for the RUDI in two patients and the ulnar artery in the other two. A branch of the cephalic vein was used to reestablish flow in the fistula for two  patients,  and a segment  of the  brachial vein was used in a third. These vein segments were of slightly smaller diameter than the venous outflow of the fistulae. The fourth patient underwent basilic vein transposition at the time of RUDI (with direct reanastomosis to the ulnar artery). Three patients reported complete   relief  of  symptoms.   The  fourth

patient had relief of pain but complained  of mild residual paraesthesia. Limb salvage and access  patency were achieved at last follow up (mean 8 months) in all cases. Corfield et

aP3 performed 3 cases of RUDI with success in  all  and  fistula  patency  of  100%.  These

results are consistent with the current study.

The development of RUDI procedure was encouraged by the use of the proximal radial artery  as inflow for  primary  AV fistulae  by Bums  and  Jennings.34  The  same  principle have been  used by  Ehsan et al, in 2005  in the  so  called  'extension   technique,35  with an  anastomosis   formed  between   proximal radial  or  ulnar  artery,  approximately   2-3 em below the brachial bifurcation, and the median antecubital vein in primary AV fistula creation. Essentially, the RUDI technique is a conversion to this configuration. This supports the use of the proximal radial (or ulnar) artery for inflow during primary fistula construction when feasible in patients thought to be at high risk for developing steal. The rationale behind this technique  is to try to preserve about half of the blood supply to the hand by using one artery beyond the bifurcation.36 This can help to prevent steal syndrome.

RUDI   both   lengthens   the   fistula   and reduces the diameter. Length is added in both the  arterial  and  venous  limbs.  RUDI  thus takes advantage of natural reductions in vessel diameter, in contrast to the artificial extrinsic constriction  of  banding.  Finally,  RUDI restores antegrade flow in the brachial artery and therefore should improve the collateral flow to the  hand in the  remaining  branches of the brachial artery. In patients without concomitant arterial occlusive disease and DASS, it may be noted that RUDI may prove superior to DRIL in that it avoids ligation of a normal artery supplying an ischemic hand.8

Conclusion:

RUDI   procedure   incorporates   most   of the advantages of other access and hand­ preserving  procedures.  By  using  a  smaller distal artery as inflow, it lengthens the fistula, decreases the radius, and preserves antegrade flow in the brachial artery. In contrast to DRIL procedure,  it  is the fistula  that  is placed  at

risk by ligation and revascularization, not the native arterial supply to  the  ischemic hand. We think RUDI may  become the  procedure of choice for patients with  dialysis-associated steal  syndrome after  a brachial artery-based arteriovenous fistula and  no  concomitant arterial  occlusive  disease.  Further follow­ up  and  assessment regarding long-term patency and  incidence of recurrence of  steal is required also  increasing number of patients subjected to the research is essential to obtain satisfactory significant results.

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