Obstetric Doppler Assessment for Placental Insufficiency

Ultrasound scanning guidelines

• Umbilical Artery Doppler (UA)
  
• Middle Cerebral Artery (MCA)
  
• Ductus Venosus Doppler (DV)
  

Umbilical Artery Doppler Umbilical Artery Doppler should be performed when: fetal biometry indicates FGR/I.U.G.R Amniotic fluid volume is reduced Maternal medical conditions related to placental insufficiency including: pre-eclampsic toxemia (PET)/pregnancy-induced hypertension (PIH) hypertension SLE and other auto-immune disorders that complicated pregnacy Maternal diabetes Growth discrepancy in twin pregnancy (significant discrepancy is a 20% difference in EFW or greater than 20mm difference in AC) Assess: Mid cord Pulse Wave spectral trace of the umbilical artery (ideally during fetal apnoea). Obtain an R.I by averaging 5 or more cycles from one trace using an auto-calculation tool, or a single cycle R.I obtained manually (depending on signal quality) Amniotic fluid volume Fetal position and presentation Documentation: Mid cord Pulse Wave spectral trace of the umbilical artery with R.I measurement Amniotic fluid volume (AFI) Presentation

Middle Cerebral Artery (MCA) Should be obtained if Umbilical Artery Doppler is equivocal or abnormal Assess: Pulse Wave spectral trace obtained in the proximal portion of the MCA. Obtain an R.I. by averaging 5 or more cycles from one trace using an auto calculation tool, or a single cycle R.I obtained manually (depending on signal quality) Documentation: Pulse Wave spectral trace of MCA with R.I. measurement

Ductus Venosus Doppler (DV) Should be obtained if the MCA or UA are abnormal Assess: Pulse Wave spectral obtained in the distal end of the DV. A single cycle, manual measurement of the S/a ratio should be obtained Documentation Pulse Wave spectral trace of Ductus Venosus with S/a measurement

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