[Influence of dihydroergotamine and leg compression on the blood volume in different regions of the body (author's transl)].

After intravenous injection of 99mTc labelled autologous erythrocytes the radioactivity of a definite body-region is proportional to the local blood volume. By whole body scintigraphy it is possible to assess simultaneous changes of blood volume in different interesting regions. By this method the influence of 1 mg dihydroergotamine i.v. was investigated in 10 patients and of compression of both legs by inflatable leg cuffs (Jobst) with pressures of 25 and 40 mmHg (3,3 and 5,3 kPa) in 7 patients. After dihydroergotamine statistically significant decreases of blood volume were found in the legs and arms and increases in the thorax and liver. Over the abdominal region there was a statistically not significant decrease of blood volume. After leg compression a statistically significant decrease of blood volume in the legs and an increase in thorax, liver and abdomen were found. The arms showed a statistically not significant blood volume increase. The blood volume diminishing effect of dihydroergotamine in the legs was 20,4% in average, of a leg compression (25 mmHg=3,3 kPa) 33,4%. Contrary to the general opinion a reduction of blood volume was also found in legs with severe varicosis. The diminution of blood volume is even more intense in such cases than in normal legs. The results after dihydroergotamine are explained by its well known constrictor effect on the capacitance vessels in the extremities.