NONINVASIVE MONITORING OF REGIONAL CEREBR AL OXYGEN-SATURATION - EXPERIENCES IN INTENSIVE-CARE MEDICINE

Regional cerebral oxygen saturation (rSO(2)) was studied in 15 healthy volunteers aged between 23 and 53 years (mean age: 34.2 +/- 8.7 years ) and in 17 intensive care patients (mean age: 37.2 +/- 18.6 years; ra nge 17-70). An infrared spectroscopy technique (INVOS(R) 3100, Somanet ics Co.) was used. The results were analysed in terms of age, heart ra te, temperature at the recording site, blood pressure and peripheral o xygen saturation. The mean +/- SD of rSO(2) was 69.4 % +/- 7.0 % in th e healthy volunteers and 66.4 % +/- 7.4 % in intensive care patients ( 65.3 % +/- 6.2 % in 7 patients with a cerebral lesion, 67.1 % +/- 8.4 % in 10 patients with no cerebral lesion). Individual examples are pre sented to show that infrared spectroscopy is a useful non-invasive met hod of investigating cerebral oxygenation. However, regional pathologi cal-anatomical limitations of the technique, and possible extracerebra l artefacts make necessary a critical interpretation of the rSO(2) val ues.