Transcutaneous determination of arterial oxygen tension

Arterial oxygen tension measurements were performed simultaneously using two different techniques: (1) the conventional method of analyzing a blood sample obtained from the radial artery by means of a Clark electrode and (2) a new method of transcutaneous oxygen tension recording using a newly developed surface electrode containing a built-in heating device to ensure optimal cutaneous perfusion at the site of measurement. Two groups of newborn infants were used as subjects: (1) 70 clinically healthy babies who were tested during normoxia and hyperoxia (breathing 80% to 100% oxygen) and (2) 20 sick preterm and term infants receiving inspired oxygen concentrations of between 21% and 100% during the measurement. Our results indicate a satisfactory accuracy for the transcutaneous oxygen tension measurements in normoxia and hyperoxia (percentage coefficient of variation, 15.9% and 24.1%, respectively). In hypoxia agreement between the two methods varies depending on the degree of circulatory derangement. Overall correlation coefficients were greater than 0.85 in each group.