[Preliminary study of the use of fetal pulse oximetry during labor].

OBJECTIVE

To assess continuous monitoring of fetal blood oxygen staturation (SpO2) during labour using a fetal pulse oxymeter.

STUDY DESIGN

Preliminary results obtained with the Nellcor N-400 fetal pulse oxymeter at the Maternité Port-Royal-Baudelocque between November 1992 and November 1993 in cases of abnormal fetal heart rate are presented. We analyzed: the correlation between SpO2 during labour and cord vein pH as well as Apgar score, the correlation between changes in SpO2, expressed as a desaturation index, and cord vein pH as well as Apgar score. The negative predictive value of oxymetry was assessed.

RESULTS

We found a significant positive correlation between the last SpO2 measurement during labour and umbilical vein pH as well as 1 minute Apgar score. We observed a highly significant correlation between the index of desaturation and cord vein pH as well as 1 minute Apgar score. No neonatal pH below 7.20 was observed when SpO2 was > or = 40% during labour. The negative predictive value of oxymetry was 100% in this short series of patients.

CONCLUSION

If these results were confirmed in a larger series of patients, a normal SpO2 value during labour could be reassuring in case of abnormal fetal heart rate.