A 66-year-old man, an ex-smoker with hypertension and hypercholesterolaemia, had undergone a Dacron bifurcated aortic graft and bilateral ureteric stents for an inflammatory aortic aneurysm with ureteric obstruction at another hospital 4 years previously. The left limb of the graft had been anastomosed to the common femoral artery and the right limb to the common iliac bifurcation. Postoperatively he had suffered a mild groin wound infection, which had healed with antibiotics. At follow-up he complained of left calf and thigh claudication. On examination, he appeared generally well with a midline abdominal scar and a left vertical groin scar. He had good right femoral pulse but an absent left femoral pulse.

Question 1

What should be the first investigation?

A.  Intra-arterial digital subtraction angiography (DSA). B.  Duplex ultrasound scan of the aortic graft.

C.  99Technetium-labelled leucocyte scan. D.  CT angiography of the graft.

E.  Erythrocyte sedimentation rate (ESR).

A duplex scan showed an occluded left limb of the aortic graft with patent common femoral arteries. There was no evidence of any stenosis of the left common femoral artery but a perigraft fluid collection was noted around the intra-abdominal portion of the graft.

C.P. Gibbons

Department of Vascular Surgery, Morriston Hospital, Swansea, UK

Question 3

Having confirmed the presence of infection what is the best option for management?

A.  Prolonged antibiotic therapy.

B.  Drainage of the perigraft pus under anaesthesia. C.  Insertion of gentamicin beads.

D.  Excision of the graft.

E.  Excision of the graft with in situ replacement with an antibiotic bonded graft. F.  Graft excision and extra-anatomical prosthetic bypass.

G.  Graft replacement with autologous vein. H.  Graft replacement with an aortic allograft.

In situ replacement with autologous vein was chosen because of the reduced risk of persistent infection.

Question 4

Which autologous veins may be used for aortoiliac or aortofemoral graft replacement?

A.  Long saphenous vein. B.  Cephalic vein.

C.  Femoropopliteal vein. D.  Iliac vein.

Femoropopliteal vein was used as it is ideally suited to supra-inguinal graft replacement as it is relatively thick-walled, is of adequate diameter and has sufficient length.

Question 5

What further preoperative investigations should be performed?

A.  Plain abdominal X-ray. B.  Bone scan.

C.  MRI scan of the abdomen.

D.  Duplex scan of the femoral veins. E.  Repeat abdominal ultrasound scan.

A duplex scan of the femoral veins confirmed that they were patent and of adequate calibre. The patient was operated on electively on the next available operating list.

Question 6

What other preoperative preparations should be undertaken?

A.  Routine full blood count.

B.  Urea and electrolyte estimation.

C.  Chest X-ray and electrocardiogram (ECG). D.  Compression stockings.

E.  Subcutaneous heparin.

F.  Combination antibiotic therapy.

Routine blood investigations, chest X-ray and ECG were all performed, and in view of the magnitude of the procedure, echocardiogram and lung function tests were also ordered. They were all satisfactory. Because the bacteriology of the infection was not known preoperatively in this patient, intravenous combination antibacterial therapy with teicoplanin, ciprofloxacin, co-amoxiclav and metronidazole was given immediately before surgery.

Question 7

How should the operation be performed?

A.  Laparotomy, excision of the aortic graft, harvesting of the femoral veins and graft replacement.

B.  Harvesting of femoral veins followed by laparotomy, excision of the infected graft and replacement with femoral vein.

C.  Laparotomy and exposure of the infected graft, then femoral vein harvest followed by graft replacement.

The anaesthetised patient was catheterised, prepared and draped so that the abdomen and both legs were exposed. First, both superficial femoral veins were simultaneously dissected out by two operative teams and the branches divided between clips from the profunda femorisveintothekneejoint.Thefemoralveinswereleftinsituwhilsttheabdomenwasopened, exposing the graft and obtaining control of the proximal infrarenal aorta and the right commoniliacbifurcation.Thegraftwasencasedinfibroustissue,makingdissectiondifficultand hazardous.Theunderlyingprosthesisshowedpoortissueincorporationandtherewasalocalised abscess between the graft and the duodenum, which was evacuated and cultured. The left groin was exposed, obtaining control of the common femoral artery, its branches and the profunda femoris artery. After systemic heparinisation, the vessels were clamped and the infected graft excised and sent for culture. The graft bed was washed repeatedly with povidone iodine and hydrogen peroxide. One femoral vein was excised, reversed and inserted end-to-end from the infrarenal aorta to the right common iliac artery bifurcation using 4/0 polypropylene sutures. Size discrepancy at the aortic anastomosis was overcome by “fishmouthing”theendoftheveintopreventtheangulationassociatedwithspatulation(Fig.39.3). Theotherfemoralveinwasreversedandanastomosedendtosidetotheintra-abdominalpart of the vein graft and to the left common femoral artery (Fig. 39.4). Both veins were led through a fresh tunnel and surrounded by greater omentum to avoid contact with the bed of the infected graft. The arterial anastomoses were covered by gentamicin-impregnated collagenfoamandthewoundswereclosedwithsuctiondrainage.Antibioticprophylaxisandlow molecular weight heparin were continued postoperatively. Despite the copious pus around the graft, no organisms were grown in the laboratory. Combination antibiotic therapy was stopped after 7 days but co-amoxiclav was continued empirically for a further 5 weeks.