title: [Reference values for the pulsatility index and the resistance index of blood flow curves of the umbilical artery and fetal aorta in the 3d trimester].
abstract: In 209 pregnancies without complications we recorded blood velocity waveforms of the umbilical artery and the foetal aorta between 29 and 42 weeks of gestation by means of a Duplex-pulsed Doppler system (umbilical artery: n = 276; foetal aorta: n = 244). We calculated the pulsatility index (PI) and the resistance index (RI). Both indices were normally distributed. The regression lines and reference ranges for the 95% confidence intervals are shown. The PI as well as the RI of waveforms of the umbilical artery demonstrated a significant fall with increasing gestation. The PI of the foetal aorta demonstrated a gentle, non-significant fall; RI showed no changes throughout the third trimester. Comparisons with the reference ranges published by other authors are discussed.
authors.affiliation: Abteilung für Geburtshilfe und Gynäkologie, LKH-Klagenfurt.
authors.forename: K
authors.initials: K
authors.lastname: Hecher
authors.forename: R
authors.initials: R
authors.lastname: Spernol
authors.forename: S
authors.initials: S
authors.lastname: Szalay
authors.forename: H
authors.initials: H
authors.lastname: Stettner
authors.forename: U
authors.initials: U
authors.lastname: Ertl
mesh_terms: D001783:Blood Flow Velocity; D005260:Female; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D008431:Maternal-Fetal Exchange; D011247:Pregnancy / Q000502:physiology*; D012016:Reference Values; D012815:Signal Processing, Computer-Assisted; D014463:Ultrasonography; D014655:Vascular Resistance
vernacular_title: Referenzwerte für den Pulsatilitätsindex und den Resistance-Index von Blutflusskurven der Arteria umbilicalis und der fetalen Aorta im dritten Trimenon.