Br. J. Surg. 1987, Vol. 74, April, 249-251 Distal arterial bypass by composite

grafting

The use of non-autogenous prostheses for femorodistal grafting has been attended by relatively poor patency rates. We have attempted to improve on these disappointing results by fashioning a composite graft using expanded PTFE (GORE-TEX) and transposed non-reversed saphenous vein, placed between the femoral artery and anterior tibial artery. We report the early results using this technique in 25 critically ischaemic limbs. A t 12 months, the cumulative graft patency for this group of patients was 65 per cent (mean follow-up of 19 months). Eighteen of the twenty-jive limbs were saved and there was no mortality. This technique offers a useful alternative to other forms of distal grafting and appears superior to the results obtained using non-autogenous

J. P. Brittont and S. H. Leveson

Department of Surgery, York District Hospital, Wigginton Road, York. UK Correspondence to: femorodistal conduits. Mr S. H. Leveson Keywords: Femorodistal bypass grafting, composite graft

Femorodistal bypass grafting offers a method of saving the critically ischaemic lower limb. The technique is now widely accepted and practised, but the success of the procedure varies with the material used for the bypass conduit.

Present evidence suggests that the most suitable bypass graft is the saphenous vein, used in situ in preference to the reversed graft. However, in many cases, the vein is neither available in sufficient length, nor of suitable calibre, certainly for the reversed technique where a vein diameter of 4mm is recommended. Studies of alternative graft materials, human umbilical vein or expanded PTFE, have produced inconsistent, but generally unsatisfactory, results and their use in distal reconstruction is probably not justified'. The technique of composite grafting with PTFE and autogenous reversed vein has been described, but problems exist because of lumen disparity at the anastomoses,

We describe tl conduit, a composite graft of GORE-TEX* and transposed tlon-reversed mphenous vein running from the fernoral artery to the antetiof tibial attefy, and report the early results.

Patients and methods Over a period of 21 months, 25 bypass grafts were performed on 24 patients using the composite graft technique described below. One patient underwent surgery to both limbs, with an interval of 3 weeks. Arteriography was performed pre-operatively on all patients, either by the translumbar route or via the femoral artery using the Seldinger technique. The operation was performed under general anaesthesia, with single dose peroperative antibiotic prophylaxis. In six early grafts, conventional 6 mm GORE-TEX was used; in the remainder, we used 6 mm thin-walled GORE-TEX. The composite anastomosis was fashioned above the knee to avoid the need for GORE-TEX to cross the knee joint.

Aspirin, 300 mg once daily, and dipyridamole, 100 mg three times daily, were prescribed postoperatively, but no other anticoagulation methods were used. Early mobilization was encouraged. The patients were followed up at 3 month intervals after discharge from hospital and patency of the graft assessed clinically and by Doppler pressure measurements .

The series included 14 men and 10 women with an age range of 52-78 years (mean age 66.6 years). Nine patients (38 per cent) were diabetic, 6 controlled on oral hypoglycaemic agents, and 3 on insulin. Fifteen patients (63 per cent) were smokers up to the time of surgery, and a further four patients had been smokers in the past. In two limbs,

* Trademark of W. L. Gore & Associates, Inc. t Present address: The General Infirmary at Leeds, Great George Street, Leeds Lsl 3 E X , UK

ipsilateral femoropopliteal in situ vein grafts had previously been performed and had occluded. In both cases, further vein was harvested from the contralateral limb.

Almost all operations were performed for limb salvage. The indications for surgery are shown in Table 1 . Pre-operative ankle/ brachial Doppler pressure indices were recordable in 10 patients: the mean pressure index was 0.25 (range 0.2C0.32).

All patients were shown to have a patent anterior tibial artery on pre-operative arteriography. There was single vessel run-off in 13 limbs (52 per cent), two vessel run-off in 10 limbs (40 per cent), and three patent vessels in 2 limbs (8 per cent).

Technique The anterior tibial artery is exposed through a lateral incision and a 4 cm length mobilized. Topical papaverins is applied. The femoral vessels are exposed through a longitudinal incision and control of the superficial femoral, common femoral and profunda femuris arteries achieved with dings The long sdphenoue Veih is mobilized distally from the shphtnofemord junction to provide an adequate length of veiti lo fun ffum the lowet thigh to the anterior tibia1 attety

After dn intravenous bolus injection of 5000 units uf hepeiih, &imps ate placed actoss the groin vesads and a longitudinal attcriotomy of approximatelfr 3 cm is made in the common femoral artery Heparinized saline is instilled into the vessels. The proximal anastomosis of 6 mm GORE-TEX to the common femoral artery is constructed by an end-to- side technique using continuous 5/0 Prolene. A clamp is placed across the graft and a satisfactory anastomosis confirmed. A 4cm longitudinal incision is made on the lateral aspect of the lower thigh and the GORE- TEX graft tunnelled using a long aortic clamp

An adequate length of long saphenous vein is removed and branches ligated with silk or clips The composite anastomosis unites the GORE- TEX graft and the proximal end of the long saphenous vein in an oblique fashion using continuous 6/0 Prolene With the clamp removed from the proximal graft, the competent valves prevent blood flow A Cartier valve stripper is passed up the vein to destroy the valves and achieve flow The vein is then tunnelled from the distal incision

With the anterior tibial artery controlled, the oblique distal end of the long saphenous vein is anastomosed to a 15-2cm longitudinal arteriotomy using continuous 6/0 Prolene Wounds are closed with suction drainage, subcutaneous catgut and skin clips.

Table 1 Indications for bypass surgery

Rest pain Necrosis/ulceration Rest pain and necrosis Severe claudication

-

0007-1323/87/04024943$3.00 0 1987 Butterworth & C o (Publishers) Ltd 249

Distal arterial bypass: J. P, Britton and 6. H. Leveeon

.- 3 404

I I 1 I 1 1 I --,I=-- I ~

0 3 6 9 12 15 18 21 24 Time (months)

Cumukutiur g r u j putenti' rule for disful bypuss wirk the Figure 1 composiie gruJt (numbers ut risk shown)

Results The patency rate of the graft and limb survival have been calculated by the life table method2. The cumulative graft patency rate is depicted in Figure 1. The overall probability of patency at 12 months is 65 per cent with a mean follow-up of 19 months. Ankle/brachial Doppler pressure indices were measured in the postoperative period; the mean pressure index for the patent grafts was 0.89 (range 062-1.3). In the grafts that failed, the pressure indices returned to the pre-operative values.

Nine (36 per cent) of the twenty-five grafts are known to have occluded. Three grafts at the beginning of the series occluded in the early postoperative period; thrombectomy and revision of the distal anastomosis was successful In two cases. Eight grafts occluded between 2 and 11 months after surgery (mean 6.1 months); thrombectomy and revision were attempted in four cases but without success, Of the nine limbs with occluded grafts, five proceeded to below-knee amputation and one to above-knee amputation. Three cases retained a viable limb not requiring amputation despite graft occlusion. One below-knee amputation was performed for rest pain dbspite a patent graft.

Minor wound sepsis was experienced in three cases and haemorrhage from the proximal anastomosis in one case. One patient had a myocardial infarction in the early postoperative period. There was no perioperative mortality.

Discussion Femorodistal grafting is a worthwhile procedure if it can be shown to save the critically ischaemic limb and prevent amputation. The major problem is the ideal choice of graft material and, to an extent, the site of the distal anastomosis. We have described a technique which may offer a satisfactory conduit for bypass grafting.

If the popliteal artery is occluded, a decision must be made to bypass on t o one of the three distal arteries. The anterior tibial artery is suitable because of its relatively superficial position and accessibility on the anterolateral side of the leg.

A cumulative graft patency rate of more than 80 per cent at 12 months has been reported using the in qitu vein graft for infrapopliteal bypass3. This technique requires the prescnce of a vein of adequate distal calibre, Situated on the medial aspect of the knee, the distal saphenous vein has to be extensively mobilized to join on to the anterior tibial artery and runs a circuitous route. The patient must be fit to withstand the necessary prolonged anaesthesia. However, the technique offers a relatively non-thrombogenic graft with appropriate flow

characteristics, anastomosing vessels of comparable lumen diameter.

Results with bypass grafting vary widely, presumably due to variation in patient selection and operatibe technique. Howcver, consistently poor results are obtained using non-autogenous conduit materials in femorodistal grafting. A recent study using glutaraidehyde-stabilized human umbilical vein for femoro- tibial grafting produced a cumulative patency of 28 per cent a t 1 year, falling to 9 per cent at 2 years4, although in contrast, Dardik achieved a patency rate of 67 per cent at 1 year'. Using GORE-TEX in the femoropopliteal position, graft patency rates have varied from 63 per cent a t 1 year' to 29 per cent at 2 years7. Although readily available and simple to insert, distal anastomoses with non-autogenous grafts are generally not favoured I

The use of composite grafts was first described in €9628. Recently, composite grafts of GORE-TEX and reversed autogenous long saphenous vein have been used for distal revascularization of ischaemic lower l i m b . The results achieved include: 63 per cent patcncy after mean follow-up of 1 t months (24 cases)'; 65 per cent after 24 months (42 cases)"; greater than 70 per cent at 12 months (76 cases)l I . The indication for surgery was limb salvage in approximately 80 per cent of cases and for claudication in approximately 29 per cent of cases. In another series, a patency rate of 81 per cent at 2 years was achieved using this composite graft for limb salvageL2. The standard technique of composite grafting is simple and relatively quick to perform, as only a short segment of vein has to b(: harvested. Difficulty is encountered because of lumen disparity between the synthetic material and reversed vein at the site of anastomosis and because the calibre of the reversed vein is often greater than that of the tibial vessels, This produces a suboptimal distal anastornotic configuration.

The described graft of GORE-TEX and transposed non- reversed long saphenous vein evolved as a method of avoiding the problems associated with the various types of conduit. We report a series of 25 cases of femoral artery to anterior tibial artery bypass using a consistent technique by the same operator (S.H.L.). A cumulative patency rate of 65 per cent at 12 months has been achieved (mean follow-up of 19 months) with 60 per cent of grafts being patent in the small number reaching 2 years. Almost all operations were for limb salvage and the need for surgical intervention in the cases reported is indicated by the fact that six of the nine limbs with occluded grafts required amputation.

In the UK, current opinion favours the use of the in situ vein for femorodistal grafting and reaeonably questions the use of synthetic conduits. We feel that this technique offers a viable alternative method for femorodistal grafting, and is associated with an acceptable patency rate.

References 1 .

2.

3.

4.

5.

6 .

I.

8.

Bell PRF Are distal vascular procedures worthwhile? Br J Surg 1985; 72: 335 . Underwood CJ, Faragher EB, Charlesworth D The uses and abuses of life-table methads in vascular surgery E r J Surg 1984,

Simms MH. Slaney F. In situ vein grirfts to the distal peroneal artery Rr J Surg 1984; 71: 308 Klimach 0, Charlesworth D Femorotibial bypasc for limb salvage using human umbilr.al vein Br J Sury 1983, 70: 1 3 Dardik H, Ibrahim I M , Jarrah M, Sussman BC, Dardik €1 Three years experience with glutaraldehyde-stabilized umbilical vein for limb salvage Rr J Surg 1980, 67: 229 32 McAuley CE, Steed DL, Webster MW Seven year follow-up of expanded polytetrafluoroethylene (PTFE) femorepopliteal bypass grafts Ann Surg 1984; 199: 57-60. Williams MR, Mikulin T, Lemberger J, Hopkinson BR, Makin GS F i v e year experience using PTFE vascular grafts for lower limb i\chaemid Ann R Coll Surg Engl 1985, 67: 152 5 Dale WA, Pridger WR, Shoulders HH Failure of composite (Teflon and vein) grafting in small human arteries Surgery 1062; 51: 258 62

71: 495-8

260 Br. J. Surg., Vol. 74. No. 4, April 1987

Distal arterial bvpaaa: d. P. Brittan and 8. H. Lsveaan

9 Snyder SO, Gregory RT, Wheeler JR, Gayle RG Composite graft utilising polytetrafluoraethylcne~auto~enaus tissiie for lower extremity arterial reconstruct~ons. Sirryrrq 1981, 90: 881 8, Gall I- P, Franke F, Raithel D. Indications, technique and results in 336 tibiaperoneal reconstructions. Cordraimc Disrure~ 1980,7: 266-7 1. Gregory RT, Raithel D, Snyder SO, Wheeler JR, Gaylc RG

10.

I I

Composite grafts: an alternative to saphenous vein for lowcr extremity arterial recanstruction. .I Carrliurcrsc Surg 1983: 24 53 7 Verta MJ. Composite scquantial bypasses to the ankle and bcyand for limb salvage. .I lbsc Surg 1984; 1: 381 85.

12.

Paper accepted 21 September 1986

Br. J. Surg. 1987, Val, 74. April, 251

Access for acute haemodialysis: a unique, pulse preserving shunt

A. H. McL. ROSS", N. Eke and A. McL. Jenkins

Vascular Unit. Royal Infirmary, Edinburgh, UK Correspondence to; Mr A. McL. Jenkins

In patients who require immediate haemodialysis for renal failure a Quinton Scribner shunt inserted at the ankle or wrist provides satisfactory vascular access'. Such shunts result in permanent reduction of arterial flow distal to the site of insertion. As a result of this, or because of the presence of occlusive diseasc, patients with a recurrent need for haemodialysis may evcntually exhaust the standard sites for temporary vascular access. Dialysis through a subclavian venous cannula is commonly uscd but may be difficult to establish and can rcsult in poor quality dialysis. Cannulation of the major limb vessel i s contra-indicated by the risk of distal ischaemic complications. However, access to the blood flow in the major vessel may be gained by creating an arteriovenous fistula between the artery and one of its venae commitantes or an adjacent vein. Insertion of the Silastic-Teflon cannula into the venous side of the fistula then allows vascular access without jeopardizing distal arterial flow

Method The brachial or superficial femoral artcries are suitable for this method, the technique being thc same whichever sitc is chosen. Under local, regional, or general anaesthesia thc artery is isolated together with a suitable adjaecnt vein (the basilic vein, the long saphenous vein, or a vena commitans). A 1 cm side-to-side arteriovenous anastomosis is made with continuous 6/0 Prolene. The vein distal to the anastornosis is cannulated with a Teflon cannula the tip of which should lie just beyond the distal end of the fistula (Figure I ) . The proximal draining vein is ligated adjacent to the fistula and a Teflon cannula tied into the vein above this to allow venous return from thc shunt tubing which emerges through adjacent stab incisions.

Removal of the shunt is achieved by simple avulsion after a period of occlusion.

Results The shunt has been constructed in 11 patients over a 7 year period (1979-1985). During this timc 354 Mastic-Teflon shunts were inserted for acute vascular access.

___ ~~- - *Present address: Department o / Surgery, Broomj?eld Hospital, BruamJield, C'helmsford, Essex CM1 J E T U K

VEIN

Figure I sume whether rhr arm or leg i s used

IIlustration ofthe construction oft he shunt The technique I F the

All 11 patients had previously undergone multiple shunt and fistula procedures. The brachial artery was used in eight cases, thc superficial femoral artery in three. Median shunt life was 9 weeks (range: 2-38). All shunts provided excellent flow rates far haemodialysis.

Eight shunts were used uneventfully until no longer required. Three shunts failed prematurely. One thrombosed 24 days after construction in a mildly demented patient on warfarin who had been known to tamper with his many shunts in the past. The second failed after developing a leak around the arterial tubing exit site 6 weeks after construction. The third shunt failure occurred in a patient with aggressive systemic lupus erythematosis, after functioning well for 2 weeks. A further patient developed mild ipsilateral arm and forearm oedema whilst under treatment in the intensive care unit. Her shunt function was unaffected. No patients developed distal arterial insufficiency.

There were no cases of haemorrhage or associated complications after removal. Distal pulses, present prc- operatively, were prcservcd in all patients.

Discussion This shunt has proved an effective and durable means of vascular access applicable t o a small group of problem patients in whom a standard shunt or subclavian cannula arc impossible to establish or provide inadequate function.

It provides a satisfactory high flow rate for dialysis. There have been no significant complications associated with its use, and it has been simple to remove using a standard avulsion technique. Despite using the brachial or superficial femoral arteries the technique ensures preservation of distal arterial flow, a major advantage. It has proved greatly superior to an earlier technique which involved the use of a short, free vein graft in which to inscrt the arterial cannula. This was prone to vein graft angulation and obstruction.

The shunt with its unique preservation of distal limb arterial flow is recommended for use in the few patients in whom standard means of vascular access have been exhausted.

References 1 . Quintan WE, Dillard BH, Cole JJ, Scribner BH. Eight months

expcriencc with Silastic-Teflon bypass cannulas. Trans Am Soc Art f lnrern Organs 1962; 8: 236-45.

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