[Reliability of the transcutaneous PO2 measurement in the adult by the TCM 1 radiometer electrode].

The accuracy of transcutaneous PO2 measurements (PtcO2; Radiometer TCM 1) was evaluated by comparison with arterial PO2 (PaO2) on 115 recordings in 35 patients: 20 during exercise testing (group I) and 14 during assisted ventilation at different FIO2 values (group II). The correlation coefficient between PaO2 and PtcO2 was satisfactory (r = 0.977; n = 115). However PaO2 and PtcO2 mean values were significantly different in group I, and in group II at 45% FIO2. The analysis of variance showed that the difference between PaO2 and PtcO2 was significant among the patients but did not vary with exercise and FIO2 changes (group I: F19 = 6.28, p less than 0.001; group II: F19(19) = 2.54, p less than 0.025). In the adult, transcutaneous PO2 measurement by TCM 1 radiometer electrode seems to be interesting in the context of monitoring blood gases with exercise and assisted ventilation. The significant variation with arterial PO2 sometimes registered should make one cautious in the interpretation of accurate measurements.