Bioeffects
LOGIQ 500 Advanced Reference Manual
2276614–100 Rev. 0
6–13
Efficacy of Fetal Doppler
The following are clinical obstetrical conditions where there are
experimental data that demonstrate the efficacy of Doppler.
Provided by John C. Hobbins, M.D. and Peter Burns, Ph.D.
4
IUGR
Many studies have shown a good correlation between abnormal
waveform (or decreased blood flow) and increased perinatal
mortality
5
, fetal hypoxia
6,7,8
, and neonatal events such as
necrotizing enterocolitis (NEC), and interventricular hemorrhage
(IVH).
8
It must be pointed out that the Doppler studies initially
designed to identify altered fetal growth had a predictably low
sensitivity
9
because the category of small for dates frequently
includes genetically small but completely normal fetuses and
neonates. Thus far, all studies have shown that the rare
Doppler pattern of reverse diastolic flow in the umbilical artery
has been very highly correlated with adverse outcome
10,11
and
may warrant immediate intervention.
Conversely, a normal
waveform in the umbilical artery has been rarely associated
with stillbirth in a high risk pregnancy.
Cardiac Anomalies
Doppler has become an integral part of fetal echocardiographic
studies. Its use has been directly derived from well
-
documented
pediatric and adult Doppler research. The etiology and
seriousness of fetal arrhythmias is relatively easy to determine
with pulsed Doppler interrogation of ventricular diastolic filling
patterns.
12–15
Benign patterns such as premature atrial
extrasystoles can be more easily diagnosed with Doppler than
with the older approach of M-Mode echocardiography. Doppler
has proven useful as well in the understanding and
interpretation of structural heart disease in the fetus. A close
correlation has been found between atrioventricular valve
regurgitation in the fetus with structural heart disease and the
appearance of non
-
immune hydrops
16
. Improved diagnostic
and prognostic ability has permitted more accurate counseling
of parents whose fetuses have structural cardiac abnormalities.
Summary of Contents for Logiq 500
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