Prediction of fetal anemia in rhesus disease by measurement of fetal middle cerebral artery peak systolic velocity

Autor: Matthias Scheier, Kypros H. Nicolaides, A. Carmo, Edgar Hernandez-Andrade, V. Dezerega
Rok vydání: 2004
Předmět:
Zdroj: Ultrasound in Obstetrics and Gynecology. 23:432-436
ISSN: 0960-7692
DOI: 10.1002/uog.1010
Popis: Objective In red blood cell (RBC) isoimmunized pregnancies fetal anemia is associated with a hyperdynamic circulation. The aim of the present study was to examine further the possible value of fetal middle cerebral artery peak systolic velocity (MCA-PSV) in the management of affected pregnancies. Methods A reference range of fetal MCA-PSV with gestation was constructed from the study of 813 normal singleton pregnancies at 20–40 weeks' gestation. Fetal MCA-PSV was also measured in 58 fetuses from RBC isoimmunized pregnancies, with maternal hemolytic antibody concentration of >15 IU/mL at 19–38 weeks' gestation and within 10 days of measurement of fetal hemoglobin concentration in blood obtained either by cordocentesis (n = 43) or at delivery (n = 15). In the RBC isoimmunized pregnancies each of the measured MCA-PSV and hemoglobin concentrations was expressed as a delta value (difference in SDs from the normal mean for gestation). Regression analysis was used to determine the significance of the association between delta MCA-PSV and delta fetal hemoglobin concentration. Results In the normal pregnancies there was a significant increase in fetal MCA-PSV with gestation (mean MCA-PSV = 100.0223 × GA + 0.963). In RBC isoimmunized pregnancies the fetal MCA-PSV was increased and there was a significant association between delta MCA-PSV and delta hemoglobin concentration (delta hemoglobin = (delta MCA-PSV + 0.093)/−0.356; R2 = 0.638, P < 0.0001). An MCA-PSV of mean + 1.5 SDs detected 96% of severely anemic fetuses, with a hemoglobin deficit of at least 6 SDs, for a false-positive rate of 14%. Conclusion Measurement of fetal MCA-PSV is a useful method of assessing fetal anemia. In the clinical management of isoimmunized pregnancies a cut-off in MCA-PSV of mean + 1.5 SDs can identify nearly all severely anemic fetuses with a low false-positive rate. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
Databáze: OpenAIRE