A scoring system to predict the outcome of long femorodistal arterial bypass grafts to single calf or pedal vessels.

OBJECTIVES

The aim of this study was to develop a scoring system to predict the outcome of long femorocrural and femoropedal bypass grafts performed for critical limb ischaemia.

SETTING

Teaching hospital.

METHODS

An analysis of 109 consecutive femorodistal bypass grafts performed for critical lower limb ischaemia between June 1991 to December 1994. Factors shown to affect the outcome were: inflow, number of patent calf vessels, graft material, straight flow to the foot and patent pedal vessels. These variables were weighted according to their relative significance (multivariate Cox regression) and a scoring system (ranging from 0 to 10) was developed.

RESULTS

Patients with a preoperative score of 0-4 (n = 35) showed a secondary patency of 36% at 1 month, 12% at 3 months and 0% at 10 months (Cum SE = 6.90/0.0). Secondary patency rates for the 46 patients with score 5-7 were 88.7% at 3 months, 56.3% at 12, and 45.1% at 2 and 3 years (Cum SE = 9.82), while the respective values for the 28 patients with score 8-10 were 92.7%, 88.5% and 81.7% (Cum SE = 8.08). The difference was highly significant (p = 0.000) in all tests of equality. In addition, the median total hospital cost was 12,600 Pounds for the group 0-4 compared with 8100 Pounds (group 5-7) and 4400 Pounds (group 8-10) (p = 0.0085).

CONCLUSIONS

This preoperative scoring system appears to correlate well with the outcome of distal revascularisation to single calf or pedal vessels. If applied to patient selection, it could significantly reduce the total hospital cost per leg saved. A prospective testing of its predictive ability is needed and is in progress.