Messgrößen in der Perinatalmedizin - pO₂und SO₂

Abstract

For fetal surveillance only oxygen saturation (%) -- not pO(2) and oxygen content -- is a useful variable. Due to the BOHR/HALDANE effect the fetus is able to rapidly mobilize his oxygen reserves and thus to compete with hypoxia; acidosis makes sense in this context. The three oxygen parameters analysed so far offer less diagnostic power than actual pH and base excess.

Die Pulsoxymetrie als additives Verfahren in der modernen Überwachung des Feten unter der Entbindung

“…Au ß erdem wurden die Phasen (10 min kontinuierlich) berechnet, die eine FSpO2 < 40 % und < 35 % beinhalteten. 60 80 100 120 140 160 180 0 20 40 60 80 100 120 140 160 180 0 20 40 60 80 100 120 140 160 180 0 20 40 60 80 100 120 140 160 180 110 100 90 80 70 60 50 40 30 20 Pulsoxymetrie mit einer durch den BOHR-Eff ekt verschleierten, kontinuierlichen pH-Messung [10] . Normwerte wie in der postnatalen Phase existieren unter der Entbindung zurzeit nicht.…”

Fetal monitoring technologies for the detection of intrapartum hypoxia - challenges and opportunities

“…Oxygen saturation is the most useful parameter for fetal monitoring. Other metrics sometimes used such as DsO 2 , the difference in oxygen between venous and arterial blood samples, is not a sensitive acid-base indicator, with its limited diagnostic value [110].…”

“…Severe fetal hypoxia will cause a high accumulation of lactic acid, a large drop in pH, and an increase in the base deficit [104]. Conversely, other biomarkers are of more limited value for example DpCO 2 is associated more with disorders of other systems [109], while DsO 2 is limited in evaluating fetal hypoxia [110]. Along with the knowledge of these biomarkers, fetal surveillance can be achieved using monitoring technologies based on biophysical parameters.…”