Outcome and cost analysis after femorocrural and femoropedal grafting for critical limb ischaemia.
BACKGROUND
The past decade has seen an increase in the use of distal arterial bypass grafts for treating critical lower limb ischaemia. However, this surgical policy is associated with variable results. The aims of this study were to identify factors that affect outcome and to calculate the cost of such surgical interventions.


METHODS
A prospective analysis of femorocrural and femoropedal bypass grafts and primary amputations was performed between June 1991 and January 1995. A consecutive series of 109 limbs with critical lower limb ischaemia underwent a bypass graft to a single crural or pedal vessel shown on either preoperative intra-arterial digital subtraction angiography or at surgical exploration. Complete data were available for all patients during follow-up which ranged from 0 to 42 (median 12) months. The factors assessed were age, sex, diabetes, pedal arch, graft material, outflow vessel, number of calf vessels, number of vessels crossing the ankle, inflow state, previous revascularization procedures and foot gangrene and tissue necrosis. Chief outcome measures were survival, knee and limb salvage, patency rates and hospital cost. The Kaplan-Meier method was used to construct life tables and the log rank test for comparison of factors. Cost was measured according to National Health Service criteria, and comparisons were made by the Mann-Whitney U test.


RESULTS
At 36 months primary patency was 27 per cent, primary assisted patency 31 per cent and secondary patency 45 per cent; limb salvage was 54 per cent, knee salvage 73 per cent and survival 58 per cent. Significant factors in predicting outcome were graft material (P = 0.004), inflow state (P = 0.0001), number of calf vessels (P = 0.039), number of vessels crossing the ankle (P < 0.0001) and the condition of pedal vessels (P < 0.0001). Cost analysis showed that the median price for a successful bypass was 4320 pounds, that of a failed bypass leading to amputation 17,066 pounds and that of primary amputation in patients with non-reconstructable distal disease 12,730 pounds.


CONCLUSIONS
The patency rate of femorotibial and peroneal bypass depends on the inflow state, the availability of a venous conduit, the number of calf vessels, the presence of straight flow to the foot and the presence of patent pedal vessels. These factors can help in the selection of patients for femorodistal reconstruction and may explain the wide variation in published results. The low cost of revascularization compared with amputation justifies attempted reconstruction. However, repeated attempts to reconstruct patients with severe distal disease who may benefit more from primary amputation will significantly increase the cost.
Panayiotopoulos
Y P
YP
Department of Surgery, Guy's and Lewisham Hospitals, London, UK.
Tyrrell
M R
MR
Owen
S E
SE
Reidy
J F
JF
Taylor
P R
PR
D000368:Aged; D000369:Aged, 80 and over; D000842:Ankle / Q000098:blood supply; D001807:Blood Vessel Prosthesis / Q000191:economics / Q000379:methods*; D003362:Cost-Benefit Analysis; D005260:Female; D005263:Femoral Artery; D005528:Foot / Q000098:blood supply; D006085:Graft Survival; D006801:Humans; D007511:Ischemia / Q000191:economics / Q000601:surgery*; D007866:Leg / Q000098:blood supply*; D008297:Male; D008875:Middle Aged; D011138:Polytetrafluoroethylene / Q000627:therapeutic use; D011446:Prospective Studies; D015996:Survival Rate; D014654:Vascular Patency
D011138:Polytetrafluoroethylene