A double-blind trial of Dextran-haemodilution vs. placebo in claudicants.

Haemodilution is often recommended for peripheral arterial disease, yet little data is available to support its clinical efficacy. This study was designed to prove or disprove the effectiveness of Dextran-haemodilution in intermittent claudication. Twenty claudicants with long, well-collateralized arterial occlusions were randomized into groups 1 and 2. Group 1 received isovolemic haemodilution with Dextran 40 (500 ml per session) during 3 weeks, which was followed by a wash-out period, followed by placebo treatments for 3 weeks. In group 2 this sequence was reversed. Pain-free and maximal walking distances were measured by standardized treadmill tests along with plethysmographic blood flow, Doppler pressures, haematocrit, blood and plasma viscosity as well as fibrinogen. Walking distances increased significantly by about 50% during haemodilution in both groups. This was paralleled by a fall in haematocrit and blood viscosity. All other variables remained constant. During placebo treatments there were no significant changes of any variable. The treatment was tolerated without complications. Thus Dextran-haemodilution seems safe and effective in selected peripheral occlusive arterial disease (POAD) patients. Potential responders might be identifiable before the start of therapy by angiographic investigations. The clinical effectiveness of Dextran 40 is comparable to that of hydroxyethyl starch 200 as reported in the literature.