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Fetal Echocardiography and Pulsed-wave Doppler Ultrasound in a Rabbit Model of Intrauterine Growth Restriction
Published on: June 29, 2013
Ultrasound examination of blood flow. I. Flow in the fetal aorta
1Department of Obstetrics and Gynaecology, Szeged University Medical School, Hungary.
The descending part of the fetal aorta was examined in a total of 101 healthy pregnant women on 146 occasions between the 28th and 41st weeks of pregnancy. A Kranzbühler 8130 Duplex Doppler apparatus was used throughout. It was found that the blood flow compared to the estimated fetal weight was near to the same value (180-200 ml/min/kg) during the third trimester. The absolute volume of blood flow--not related to fetal body weight--increased about three times from the 28th week to term (200-600 ml/min). The diameter of the fetal aorta increased from 3-4 mm to 7-8 mm during the 3rd trimester. The velocity of blood flow fluctuated between wide limits (20-40 cm/sec), but the average was 28-32 cm/sec. The A/B ratios (A = systolic peak, B = end diastole), the Resistance Indexes (A-B/A), the Pulsatility Indexes (A-B/mean frequency) were nearly the same during the third trimester.
The descending part of the fetal aorta was examined in a total of 101 healthy pregnant women on 146 occasions between the 28th and 41st weeks of pregnancy. A Kranzbühler 8130 Duplex Doppler apparatus was used throughout. It was found that the blood flow compared to the estimated fetal weight was near to the same value (180-200 ml/min/kg) during the third trimester. The absolute volume of blood flow--not related to fetal body weight--increased about three times from the 28th week to term (200-600 ml/min). The diameter of the fetal aorta increased from 3-4 mm to 7-8 mm during the 3rd trimester. The velocity of blood flow fluctuated between wide limits (20-40 cm/sec), but the average was 28-32 cm/sec. The A/B ratios (A = systolic peak, B = end diastole), the Resistance Indexes (A-B/A), the Pulsatility Indexes (A-B/mean frequency) were nearly the same during the third trimester.
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