Duplex scan surveillance during the first year after infrainguinal autologous vein bypass grafting surgery: Costs and clinical outcomes compared withother surveillance programs

Purpose: In this study we assessed the costs and clinical outcomes of duple x scan surveillance during the first year after infrainguinal autologous ve in bypass grafting surgery and compared duplex scan surveillance, ankle-bra chial index surveillance, and clinical follow-up. Methods: In a clinical study, 293 patients (mean age, 70.1 years; 58.7% men ) with peripheral arterial disease were observed in a duplex scan surveilla nce program after infrainguinal autologous vein bypass grafting surgery. Co sts were calculated from the health care perspective for surveillance and s ubsequent interventions from 30 days to 1 year post operatively. All costs are presented in 1995 US dollars per patient. In a simulation model, we est imated the costs and amputations of duplex scan surveillance, ankle-brachia l index surveillance, and clinical follow-up conditional on the indication for surgery The main outcome measure was the incremental cost per major amp utation per patient avoided during the first postoperative year. Results: Duplex scan surveillance was the least expensive ($2823) and resul ted in the fewest major amputations (17 per 1000 patients examined), compar ed with ankle-brachial index surveillance ($5411 and 77 amputations per 100 0 patients) and clinical follow-up ($5072 and 77 amputations per 1000 patie nts). In patients treated for critical limb ischemia, duplex scan surveilla nce was the least expensive ($2974) and resulted in the fewest major amputa tions (19 per 1000 patients). Under all surveillance programs, 13 major amp utations per 1000 patients treated for intermittent claudication were perfo rmed, and clinical follow-up had the lowest costs ($1577). In a sensitivity analysis that assumed that duplex scan surveillance could have avoided six major amputations per 1000 patients treated for intermittent claudication compared with the other programs, duplex scan surveillance had an increment al cost of $80,708 per major amputation per patient avoided compared with c linical follow-up. Conclusion: Duplex scan surveillance is highly effective for patients treat ed for critical limb ischemia, leading to a reduction of major amputations and consequently to a reduction in costs compared with other surveillance p rograms. In patients treated for intermittent claudication, the evidence su pporting duplex scan surveillance is less firm, but if duplex scan fan avoi d six major amputations per 1000 patients examined, the incremental costs a re justified.