Objectives: Investigate the prediction of birth acidemia in pregnancies with placental insufficiency using two newly created venous-arterial Doppler ratios: pulsatility index (PI) of the ductus venosus (DV) over PI of the middle cerebral artery (MCA) and PI of the DV over PI of the umbilical artery and establish cut-off values for this prediction.
Methods: This was a prospective cross-sectional study involving 47 patients with placental insufficiency managed in two Brazilian hospitals. All pregnancies were singleton, over 26 weeks of age and without structural or chromosome anomalies. A ROC curve was calculated for the venous-arterial ratios (independent variable) and acidemia (dependent variable).
Results: The DV/AU PI ratio was not a good predictor of acidemia at birth. The DV/MCA PI ratio was related to fetal acidemia (area under the ROC curve 0.785, p = 0.004). The cut-off value was 0.582, sensibility 66.7%, specificity 77.1% and accuracy 74.5%.
Conclusions: The DV/MCA PI ratio is adequate for the diagnosis of acidemia at birth in pregnancies with placental insufficiency. The cut-off value was 0.582.
2006 S. Karger AG, Basel