Hematocrit dependent changes of muscle tissue oxygen supply in the lower limb muscle of patients with intermittent claudication.

Hematocrit dependent changes of muscle tissue oxygen supply at rest and after exercise were detected in 23 patients with chronical arterial occlusive disease stage IIb according to Fontaine. In these patients with a concomitant high hematocrit a stepwise isovolemic hemodilution by vena esection and subsequent infusion of 10% hydroxyethylstarch solution (200/0.5%) was achieved intraindividually. Measurements of muscle tissue oxygen pressure (pO2) values in the lower limb muscle using a standardized pedalergometric exercise test as well as pain free walking distance with a treadmill were performed. Improvement of muscle tissue pO2 supply after pedalergometric exercise as well as muscular performance on the treadmill were found at an average hematocrit value of 40.50%, whereas muscle tissue oxygen supply and pedalergometric performance were markedly reduced at hematocrit 50.60% as well as 33.75%. Thus it is likely that an improvement of muscle tissue oxygen supply in severe intermittent claudication can be achieved by isovolemic hemodilution to hematocrit values about 40-41%.