title: Umbilical artery Doppler velocimetry as a predictor of fetal hypoxia and acidosis at birth.
abstract: We studied the relationship between preoperative umbilical artery Doppler waveforms and umbilical vein pO2 and pH at elective cesarean section. An absence of end-diastolic velocities had a strong statistical association with hypoxia and acidosis, and was an accurate clinical test for hypoxia (sensitivity 78%, specificity 98%, positive predictive value 88%, and negative predictive value 98%) and acidosis (sensitivity 90%, specificity 92%, positive predictive value 53%, and negative predictive value 100%). It was also a clinically sensitive indicator of perinatal morbidity and mortality. Most fetuses with no end-diastolic velocities were growth-retarded, but the reverse was not true. The absence of end-diastolic velocities also divided both mature and immature fetuses into high- and low-risk groups for hypoxia and acidosis. In the presence of end-diastolic velocities, only very high S/D ratios (above 4.5) have any association with hypoxia. As a noninvasive test of fetal umbilical vein pO2 and pH, umbilical artery Doppler performs well.
authors.affiliation: University Department of Obstetrics and Gynecology, St. James's Hospital, Leeds, England.
authors.forename: S
authors.initials: S
authors.lastname: Tyrrell
authors.forename: A H
authors.initials: AH
authors.lastname: Obaid
authors.forename: R J
authors.initials: RJ
authors.lastname: Lilford
mesh_terms: D000138:Acidosis / Q000175:diagnosis* / Q000503:physiopathology; D001783:Blood Flow Velocity; D005260:Female; D005317:Fetal Growth Retardation / Q000453:epidemiology / Q000503:physiopathology; D005311:Fetal Hypoxia / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007231:Infant, Newborn; D007234:Infant, Premature / Q000502:physiology; D010100:Oxygen / Q000097:blood; D011237:Predictive Value of Tests; D011247:Pregnancy; D011263:Pregnancy Trimester, Third; D011296:Prenatal Diagnosis; D014463:Ultrasonography; D014469:Umbilical Arteries / Q000503:physiopathology*
chemical_list: D010100:Oxygen