[Fetal pulse oximetry: from the first experimental studies of broad clinical use. An assessment of current status]

Pulse oximetry has triggered a revolutionary change in monitoring patients in many branches of medicine. For 4 years fetal sensors with specially calibrated pulse oximeters are tested clinically. Additional examination methods are required for accurate monitoring the fetus intrapartum because of the low specificity of cardiotocographs and also to avoid unnecessary operative deliveries. Research on hand up to now has demonstrated that fetal pulse oximetry is a method easy to learn, easily applicable and well quanitifiable to improve fetal monitoring and the interpretation of the fetal heart rate patterns intrapartum. Prospective intervention studies involving management studies still have to prove the clinical value of this new technology. Only after examining a large number of hypoxic-risk fetuses we can assess whether pulse oximetry in a management can replace invasive fetal blood analysis as a continuous, non-invasive method of monitoring. Various teams try to prove a context between arterial saturation values (SpO2) and biochemical changes of the fetus in connection with a crucial limiting value of 30% by correlating changes of the fetal scalp with the oxygen saturation. Guidelines for the assessment of the SpO2-values are established according to the present level of knowledge and future aspects of the method are examined.