The oxygen supply of body organs is clinically estimated by parameters of whole body oxygen transport and hemodynamics. However, the oxygen delivery to a certain organ is not necessarily indicated by changes in these parameters. Even if cardiac output is measured by Swan Ganz thermodilution technique, thus allowing calculation of the whole body oxygen delivery, its distribution to different organs is unknown and might change, particularly in peripheral organs (e.g. in shock, by administration of vasoactive drugs) (Abrams 1985, Feltes et al. 1987, Slater et al. 1973). Therefore, clinically applicable devices for measurement of the distribution of oxygen partial pressure within peripheral organs have been developed (Kessler and Lübbers 1966, Ehrly 1987, Weiss and Fleckenstein 1986) with the aim to determine the state of oxygen supply more directly.