title: Venous-arterial Doppler ratios in the prediction of acidemia at birth in pregnancies with placental insufficiency.
abstract: OBJECTIVE
  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.
authors.affiliation: São Paulo Hospital, São Paulo Federal University, Paulista Medical School, Fortaleza, Brazil. herlaniocosta@uol.com.br
authors.forename: F H C
authors.initials: FH
authors.lastname: Carvalho
authors.forename: A F
authors.initials: AF
authors.lastname: Moron
authors.forename: R
authors.initials: R
authors.lastname: Mattar
authors.forename: C G V
authors.initials: CG
authors.lastname: Murta
authors.forename: R M
authors.initials: RM
authors.lastname: Santana
authors.forename: M M
authors.initials: MM
authors.lastname: Barbosa
authors.forename: M R
authors.initials: MR
authors.lastname: Torloni
authors.forename: F A P
authors.initials: FA
authors.lastname: Vasques
mesh_terms: D000138:Acidosis / Q000097:blood* / Q000175:diagnosis* / Q000209:etiology; D000293:Adolescent; D000328:Adult; D001158:Arteries; D003430:Cross-Sectional Studies; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007231:Infant, Newborn; D020768:Middle Cerebral Artery; D010927:Placental Insufficiency / Q000000981:diagnostic imaging*; D011247:Pregnancy; D011446:Prospective Studies; D011673:Pulsatile Flow; D012372:ROC Curve; D012680:Sensitivity and Specificity; D018617:Ultrasonography, Doppler, Pulsed; D014469:Umbilical Arteries; D014680:Veins / Q000196:embryology