Quantitative continuous measurement of partial oxygen pressure on the skin of adults and new-born babies

Summary It is possible to perform continuous quantitativeP_O2 measurements on vasodilated skin by means of surface Pt electrodes according to Clark when the electrode is fixed to the skin with a synthetic plastic material and in situ calibration is performed. A new in situ calibration of theP_O2 electrode is described. At first the skinP_O2 increases with O₂ inspiration. After perfusion stop the skinP_O2 shows a linear decrease because of the skin respiration, down to aP_O2 at which hemoglobin liberates chemically bound O₂. As thisP_O2 value of hemoglobin is known it is possible to use it for calibrating the electrode. TheP_O2 of normal skin is about 0–7 Torr. After vasodilation obtained by rubbing with a nicotinic acid derivate (Finalgon^®, Anasco, Wiesbaden),P_O2 increases to a mean value of 38.1 (±8.1) Torr (n=77). Under these conditions, skinP_O2 reaches arterial values never in adults and rarely in new-born babies.Part of the results have been reported during the Workshop on Oxygen Transport in Tissue, 19–22 July, 1971, in Dortmund and at the 4. Deutsche Kongress für Perinatale Medizin, 4–6 Nov. 1971, in Berlin. The study was carried out with partial support from the German Research Council (DFG).