A Placebo-Controlled Study of the Effects of Intravenous Buflomedil on Foot Skin Microcirculation in Patients with Severe Intermittent Claudication

Abstract

Buflomedil hydrochloride (Buflomedil), a vasoactive drug, has been proven to improve pain-free walking distance in patients with peripheral arterial occlusive disease stage II of the lower extremities. In the present double-blind, randomized study, resting skin flux motion activity and skin flux response to a local heat stress at the hallux were assessed by laser Doppler fluxmetry (LDF) in claudicants. Twenty of 39 enrolled patients with severe intermittent claudication received a daily intravenous dose of 400 mg Buflomedil, and the other 19 patients received 0.9% NaCl as placebo over a 5-day period. Before treatment mean LDF skin resting flux, flux frequency, and flux amplitude were 2 ±0.8 Arbitrary Units (AU), 8.4 ±0.5 cycles per minute (c/min), and 0.12 ±0.01 AU, respectively in the Buflomedil group, and 2.3 ±0.3 AU, 8.7 ±0.7 c/min, and 0.13 ±0.02 AU in the placebo group (NS). Also the response to heat stress was identical in both groups: a slow initial increase of skin flux, followed by a reflex reduction, with a maximal initial flux increase to 138 ± 12% of the resting value in the Buflomedil group, and 155 ± 16% in the placebo group (NS). (continued on next page) After 5 days of treatment the mean LDF skin resting flux, flux frequency, and flux amplitude were unchanged in both patient groups. The response to heating on the contrary was dramatically enhanced in the Buflomedil group (226 ±33%), against that in the placebo group, which remained unchanged (144 ±13%) after 3 minutes (P<0.05), while after reflex reduction the flux in the Buflomedil group remained stable at 200% of resting value during further heating and was only approximately 140% in the placebo group (P<0.05). It is concluded that Buflomedil, administered in a daily intravenous dose of 400 mg, does not alter the mean LDF skin flux and flux motion at the hallux in claudicants in resting conditions. Local skin heating on the contrary provokes a significant LDF monitored skin flux increase, suggesting an improved capacity of cutaneous microvessel perfusion in stressed conditions.