[Non-invasive determination of oxygen saturation with the oxygenmet pulse wave oximeter. Comparison with the invasive reflectometric method (author's transl)]. / Nichtinvasive Messung der Sauerstoffsättigung mit dem Oxygenmet-Oximeter. Vergleich mit der invasiven reflektometrischen Methode.

Oxygen saturation was determined non-invasively with the oxygenmet pulse wave oximeter 1471 and at the same time with the invasive reflectometric method. The determinations were carried out on 49 children (males = 24, females = 25) during 52 catherizations of the heart. Among these children aged between one week and 15 years were 11 children suffering from cyanotic heart disease. Depending on age and health condition 1-8 blood samples from different arterial regions were analysed reflectometrically. The comparison between the oxygen saturations determined non-invasively with the oxygenmet oximeter and the oxygen saturations obtained invasively with the aid of the reflectometric method, showed a very close correlation (r = 0.923), however the differences were statistically significant. The comparison of the calculated regression line with the ideal regression line revealed that the values of the two methods differed considerably, especially in the range of low oxygen saturations. The causes for these differences, especially the absorption effect of the skin and the subcutaneous tissue of cyanotic patients, were discussed.