Influence of normovolemic hemodilution with 10% HES 200 on tissue PO2 in the M. tibialis ant. of 7 male volunteers.

The aim of the present study was to investigate the effect of normovolemic hemodilution with a middle molecular HES solution on oxygen supply and PO2 pressure distribution in the extremity muscles of healthy male subjects. In addition to a significant reduction of the hematocrit (Hct) by hemodilution from about 44% to about 37% and unchanged arterial blood gas values, an increase of the mean muscle PO2 from about 16 mmHg (before hemodilution) to about 27 mmHg (30 minutes after having reached normovolemia) was observed. The increase of the mean tissue PO2 is demonstrable already 30 minutes after the start of infusion (t = 30) (see Table 2). The markedly raised level of the tissue PO2 in the M. tibialis anterior as compared with the initial value is demonstrable both during and after normovolemic hemodilution. In addition to this dilution-related increase of the mean tissue PO2, a marked change of configuration of the PO2 histograms is found. There is an increase filling of the PO2 classes in the pressure ranges above 40 mmHg. The conspicuous increase of the intra-individual dispersion of PO2 mean values during and after infusion of HES 200 cannot be interpreted for the moment. Similar observations were, for example, reported by Landgraf and Ehrly in 1985 when measuring the muscular tissue oxygen pressure in patients with intermittent claudication before, after and during infusion of 0.9% saline solution. This could be interpreted as an increased perfusion of certain areas of the muscular capillary system.(ABSTRACT TRUNCATED AT 250 WORDS)