Non-invasive continuous fetal transcutaneous pO2 and pCO2 monitoring during labor

: Continuous measurements of fetal scalp transcutaneous pO2 (tcpO2) and pCO2 (tcpCO2) monitoring were performed for 49 patients for the purpose of the evaluation of the fetal well-being. The equipment used was transcutaneous pO2/pCO2 monitor Micro Gas 7640 (KONTRON, Switzerland), which was inserted through the vagina and attached to the fetal head with a suction ring. Blood was taken from the umbilical vessels and pO2 and pCO2 values were analyzed. The correlation coefficient between pO2 in the umbilical artery and tcpO2 was 0.78 (p less than 0.01), and that between pCO2 in the umbilical artery and tcPCO2 was 0.79 (p less than 0.01). Relationships between the transcutaneous blood gas analysis and FHR patterns were discussed. Increase of pCO2 and decrease of tcpO2 was observed in the cases of variable deceleration, not observed in the case of early deceleration. FHR patterns don't always indicate fetal condition, for example in the case of fetal arrhythmia, especially fetal bradycardia. But tcpO2 monitoring of the fetus affected fetal arrhythmia during labor aids diagnosis of fetal distress by FHR patterns, especially in the case of fetuses affected by fetal bradycardia.