title: The effect of cordocentesis on umbilical and middle cerebral artery blood flow velocity waveforms.
abstract: OBJECTIVE
  To investigate the effect of cordocentesis on the umbilical and fetal cerebral circulation.
  
  
  METHODS
  Cross sectional study.
  
  
  METHODS
  Department of Obstetrics and Gynaecology, Regional Referral Centre for Fetal Medicine, Klagenfurt Hospital, Austria.
  
  
  METHODS
  Thirty pregnant women undergoing diagnostic cordocentesis at 18 to 38 weeks' gestation.
  
  
  METHODS
  The pulsatility index (PI) in the umbilical artery and fetal middle cerebral artery was measured by pulsed Doppler ultrasound before and immediately after cordocentesis.
  
  
  METHODS
  Change in umbilical artery PI and middle cerebral artery PI.
  
  
  RESULTS
  Cordocentesis was associated with a significant decrease in both umbilical artery PI (median -0.18, range -2.21 to 1.5, P < 0.004) and middle cerebral artery PI (mean -0.15, SD 0.32, P < 0.03) and the decrease in umbilical artery PI was most marked when cordocentesis was performed transplacentally. In four cases, there were absent or reversed frequencies at the end of diastole (EDF) in the umbilical artery before cordocentesis, and in all cases there were positive EDF after the procedure. In contrast, one of the 26 cases with positive EDF developed reversed EDF following the procedure.
  
  
  CONCLUSIONS
  Acute alterations in the waveforms from both the umbilical and fetal cerebral circulation can be induced by cordocentesis. The decrease in resistance in the fetoplacental circulation could be attributed to the release of vasodilators, and the increase in resistance observed in some cases could be secondary to arterial vasospasm. Better understanding of the underlying mechanisms might help in making cordocentesis a safer procedure.
authors.affiliation: Department of Obstetrics and Gynaecology, Klagenfurt Hospital, Austria.
authors.forename: K
authors.initials: K
authors.lastname: Hecher
authors.forename: H
authors.initials: H
authors.lastname: Stettner
authors.forename: R
authors.initials: R
authors.lastname: Spernol
authors.forename: K
authors.initials: K
authors.lastname: Harrington
authors.forename: S
authors.initials: S
authors.lastname: Szalay
mesh_terms: D001783:Blood Flow Velocity; D002560:Cerebrovascular Circulation / Q000502:physiology*; D017218:Cordocentesis / Q000009:adverse effects*; D003430:Cross-Sectional Studies; D005260:Female; D005333:Fetus / Q000098:blood supply; D005865:Gestational Age; D006801:Humans; D011247:Pregnancy; D011296:Prenatal Diagnosis; D014463:Ultrasonography; D014469:Umbilical Arteries / Q000000981:diagnostic imaging / Q000502:physiology*