FETAL MONITORING OF DELIVERY BY OXYCARDIO TOCOGRAPHY (OCTG)

Oxycardiotocography is a combination of cardiotocography and continuou s registration of the foetal arterial oxygen saturation (SaO2). In a f ew cases, the value of this additional information of foetal SaO2 is d emonstrated. During uncomplicated deliveries with normal foetal heart rate patterns, the foetal SaO2 usually ranges between 50 % and 70 %. U terine hyperactivity with impaired perfusion of the placenta shows bes ides a changed heart rate patterns, a significant decrease of the foet al oxygen saturation. Conversely, by supplying oxygen to the mother wi th a mask, the foetal oxygen saturation can be increased by approx. 10 %. In case of a breech presentation and application of the sensor to the buttocks, the measured O2-saturation is approx. 10 % to 15 % below the values usually obtained from the scalp because the tissue there i s supplied with mixed blood after the ductus.