Journal of Ultrasound in Medicine, Vol 4, Issue 9 453-458, Copyright © 1985 by American Institute of Ultrasound in Medicine
Serial echo-Doppler measurements of human fetal abdominal aortic blood flow
M. W. Eldridge, W. Berman Jr and E. R. Greene
An echo-Doppler duplex scanner (DS) was used to make serial noninvasive
measurements of human fetal abdominal aortic blood flow (Q). In 18
uncomplicated pregnancies (16 weeks to term), Doppler shifted frequency
spectral waveforms (delta f), Doppler incident angles (theta), and peak
systolic lumen diameters (D) were measured. Using the measured values of
delta f and theta, the temporal average blood velocity (V) in the cardiac
cycle was calculated from the Doppler equation. Values of Q were calculated
using the equation: Q = pi X (D2/2) X V X HR, where HR is the heart rate.
Gestational age (GA) and fetal weight (FW) were estimated from biparietal
and transverse abdominal diameters. Each fetus was studied three to eight
times at 2- to 4-week intervals. Results showed that Q increased
nonlinearly with GA. Normalized to estimated FW, values of Q/kg did not
vary significantly with estimated GA and gave an overall mean value (+/-
standard deviation) during gestation of 184 +/- 35 ml/kg/min.
