Download Middle cerebral artery Doppler waveforms

Doppler Ultrasonography in
Obstetrical Practice
China Medical University Hospital
OBS & GYN department
Chien Chung, Lee
Conditions That Place Fetuses at Risk for Adverse Outcomes
Maternal
Chronic hypertension
Collagen-vascular
diseases
Sickle cell anemia
Current substance abuse
Impaired renal function
Asthma
Pneumonia
Significant cardiac
disease
Seizure disorders
Diabetes
Acute febrile illnesses
Significant anemia
(hematocrit <26%
Fetal
Intrauterine growth
restriction
Congenital
anomalies
Fetal cardiac
arrhythmias
Isoimmunization
Hydrops fetalis
Fetal infections such
as parvovirus,
coxsackievirus B,
syphilis,
toxoplasmosis
Pregnancy-related
Poorly controlled
gestational diabetes
Multiple gestations
Pregnancy-induced
hypertension
Cholestasis of pregnancy
Premature rupture of the
membranes (preterm)
Unexplained elevated
maternal
serum alpha-fetoprotein
Polyhydramnios
Oligohydramnios
Placental abruption
Abnormal placentation
Postdates
Unexplained stillbirth in a
prior pregnancy
General Guidelines for Antepartum Testing
Indication
Initiation
Frequency
Post-term pregnancy
41 weeks
Twice a week
Preterm rupture of the membranes
At onset
Daily
Oligohydramnios
26 weeks or at onset
Twice a week
Polyhydramnios
32 weeks
Weekly
Class A1 DM (well-controlled, no complications)
36 weeks
Weekly
Class A2 and B (well-controlled, no complications)
32 weeks
Twice a week
Class A or B with poor control, Class C-R
28 weeks
Weekly
Chronic or pregnancy-induced hypertension
28 Weeks
Weekly
Steroid-dependent or poorly controlled asthma
28 Weeks
Weekly
Collagen-vascular disease including antiphospholipid
antibody syndrome
28 Weeks
Weekly
Impaired renal function
28 weeks
Weekly
Uncontrolled thyroid disease
32 weeks
Weekly
Maternal heart disease (NYHA class III or IV)
28 weeks
Once a week
Substance abuse
32 weeks
Weekly
At 2 weeks before prior fetal death
Weekly
32 weeks
Weekly
Fetal growth restriction
26 weeks or at onset
Twice a week
Decreased fetal movement
At time of complaint
Once
32 weeks
Weekly
Prior stillbirth
Multiple gestation
Cholestasis
Biophysical profile for fetal assessment in high
risk pregnancies (Cochrane Methodology Review)
Reviewers' conclusions: At present, there is not
enough evidence from randomised trials to evaluate
the use of biophysical profile as a test of fetal wellbeing in high risk pregnancies.
Alfirevic Z, Neilson JP. In: The Cochrane Library, Issue 4, 2003.
Doppler ultrasound for fetal
assessment in high risk pregnancies
(Cochrane Methodology Review)
Reviewers' conclusions: The use of Doppler
ultrasound in high risk pregnancies appears to
improve a number of obstetric care outcomes
and appears promising in helping to reducing
perinatal deaths.
Neilson JP, Alfirevic Z. . In: The Cochrane Library, Issue 4, 2003.
Descriptive characteristics of randomized trials evaluating the use of Doppler
ultrasonography in pregnancy included in overview
Reference
No. of
participant
Perinatal
deaths (%)
Type of Doppler ultrasonography used
AEDV
(%)
Trudinger et al.,
1987,
l289
2.1
Umbilical artery, CW 4 MHz
McParland and
Pearce, 1988
509
5.1
Umbilical and uterine arteries, PW
15.1
Death before discharge from hospital
Tyrell et al., 1990
500
1.2
Umbilical and uterine arteries, CW, 4 MHz,
100 hZ
2.7
No. of days in neonatal intensive care
unit, frequency of low Apgar score
Hofmeyr et al.,
1991
897
1.3
Umbilical artery, CW, 4 MHz, 50 Hz filter
Newnham et al.,
1991
545
3.3
Umbilical artery, CW, 280 Hz filter
Burke et al., 1992
476
1.5
Umbilical artery, CW, 4 MHz, 150 Hz filter
?
Not stated
Almstrom et al.,
1992
426
0.7
Umbilical artery, PW, 3 MHz, 100 Hz filter
1.9
Not stated
Biljan et al., 1992
674
0.7
Umbilical artery, CW, 4 MHz, 100 Hz filter
1.3
No. of antenatal tests per patient,
duration of antenatal stay
Johnstone et al.,
1993
2329
1.2
Umbilical artery, CW, 4 MHz, 60-80 Hz filter?
Pattison et al.,
1994
212
6.6
Umbilical artery, CW, 4 MHz, 100 Hz filter
9.4
Perinatal mortality
Neales et al
467
5.3
Umbilical artery, CW, 4 MHz
6.4
Not stated
Nienhuis and
Hoogland
150S
3.4
Umbilical artery, PW, 50 Hz filter
?
Not stated
?
?
2.9
?
Controls Prespecified primary end
point with sample size calculations
Gestational age at delivery
Not stated
Neonatal hospital stay
Not stated
Proportional effect of Doppler ultrasonography on number of dead babies
(stillbirths and neonates) when used in high-risk pregnancies.
Meta-analysis shows that clinical action guided by Doppler ultrasonography reduced the
odds ratio of perinatal death by 38%
Effects of Doppler ultrasonography on perinatal outcomes in
high-risk pregnancies. Post hoc analysis.
The 16% reduction in the number of elective deliveries, 31% reduction in fetal distress in labor, and
87% reduction in hypoxic encephalopathy in the Doppler group reached statistical significance.
Conditions for Doppler ultrasound
(1)
Pregnancies complicated by IUGR
(2)
Pregnancies in which the fetus is at risk for anemia
(3)
Multiple gestations
(4)
Pregnancies treated with prostaglandin inhibitors to
monitor the ductus arteriosus
Fetal echocardiograms
(5)
Doppler Flow Velocity in the First Trimester
Comparison of endometrial thickness, RI, & gestational age between groups
Retained tissue
Not retained tissue
P
Gestational age
10.0(3.3)
7.6(2.0)
0.001
Endometrial
thickness(mm)
19.5(1.8)
10.2(7.0)
0.001
RI
0.38(0.16)
0.59(0.12)
0.001
Alcazar JL, Ortiz CA. Eur J Obstet Gynecol Reprod Biol. 2002 Apr 10;102(1):83-7.
Doppler Flow Velocity in Uterine Artery
Bewley et. al.
Br J Obstet Gynaecol 1989;96:1040–6
(A) Normal uterine artery at 12 weeks shows
relatively high resistance, absent notching.
(B) Normal midtrimester uterine artery,
increased diastolic flow.
(C) Normal third trimester uterine artery, very
low resistance.
(D) High resistance with persistent notching
may be normal in first trimester, not in this
24-week gestation.
(E) Very high resistance, marked notching,
absent diastolic velocities in a woman with
pre-eclampsia, and severe intrauterine
growth restriction (IUGR) at 28 weeks.
Doppler Flow Velocity in Umbilical Artery
(A) Normal umbilical artery at 18 weeks shows
relatively high resistance, but consistent
diastolic flow.
(B) Normal umbilical artery at 36 weeks, low
resistance, generous diastolic flow.
(C) High resistance, diastolic velocity low.
(D) Absent end-diastolic velocity (AEDV).
(E) Reversed diastolic velocity (REDV) in
severe intrauterine growth restriction (IUGR).
Doppler Flow Velocity in Umbilical Artery
Fetuses with absent end-diastolic velocity
of the umbilical artery all died in utero
within 3 weeks (median 7 days).
Madazli R, Uludag S, Ocak V.
Acta Obstet Gynecol Scand 2001; 80:702
FACTORS AFFECTING UMBILICAL ARTERY DOPPLER FLOW
VELOCITY WAVEFORMS
Gestational age
EDFV ratio increases with advancing gestational age
Fetal heart rate
EDFV decreases with decreasing fetal heart rate
Fetal breathing movements
Increases variability in the measurements
Site of measurement
EDFV is higher near the placental insertion than near the
umbilical cord insertion into the fetal abdomen
Equipment used : continuous Doppler
versus pulsed Doppler
Continuous Doppler is more a “blind technique” compared
with pulsed Duplex Doppler, allowing 2D real time ultrasound
User experience
Reliability increases with increasing experience
Radius of the umbilical artery
Decreasing radius (vasoconstriction) increases EDFV
Impedance to pulsatile flow propagation
Increasing vascular impedance increases EDFV
Downstream vascular resistance within the
microcirculation
Increasing vascular resistance decreases EDFV
Angle of the fetal Doppler insonation
Best if less than 45˚; <15˚ for MCA absolute peak systolic
flow
velocity
Diagnostic efficacy of umbilical arterial Doppler in IUGR
Author
DI
Prevalence
Sensitivity
Fleischer
Aruidini
Berkowitz
Divon
Gaziano
Ott
Maulik
Lowery
Lee
Specificity PPV
S/D>3.0
16.8
78
83
49
PI>1SD
S/D>3.0
S/D>3.0
S/D>4.0
S/D>3.0
S/D>2.9
S/D>4.0
S/D>3.0
30.7
25
35.4
9.4
10.4
12.3
22.6
15
60.8
55
49
79
59
75
65
91.7
73
92
94
66
84
71
66
68.7
50
73
81
79
29
27
24
84.6
Middle cerebral artery Doppler waveforms
Normal flow of the Middle Cerebral Artery in 1º
trimester
Normal flow of the Middle Cerebral Artery in
2º and 3º trimester
Middle cerebral artery Doppler waveforms
(A) Normal middle cerebral artery (MCA) at term
- normal peak systolic velocity (58 cm/s), high
resistance, low end-diastolic velocity.
(B) ‘Brain sparing’ MCA - lower peak, much
higher diastolic velocity suggests
cerebrovasodilation.
(C) Anemic fetus with retained high resistance,
elevated peak systolic velocity (77 cm/s).
Doppler Flow Velocity in Ductus venosus
The upper panel represents the venous waveform,
correlated with the EKG in the lower panel. A = atrial
systole, S = ventricular systole, D = early ventricular
diastole. The colored portions of the waveform
represent the Tamx for atrial systole (gold), ventricular
systole (red), and early ventricular diastole (blue). The
yellow arrows represent the measurement of the peak
velocity for ventricular systole and early ventricular
diastole. The black arrow represents the peak velocity
for atrial systole.
(A) Ductus venosus (DV) Doppler
waveforms at 12 weeks gestation.
(B) At 12 weeks gestation, an abnormal awave (a), correctly predicted anomalous
pulmonary and systemic venous return,
proven by fetal echocardiography at 24
weeks.
(C) DV at 26 weeks, with 4-phase waveform.
(1) atrial contraction (2) ventricular systole, (3)
return (ascent) of the annulus (called the ydescent of the DV waveform), & (4) diastole.
(D) Normal waveform from the middle
hepatic vein which, is only a few millimeters
from the DV.
Doppler Flow Velocity in IUGR
Progressive changes in Doppler parameters in IUGR fetuses delivered for an
abnormal Biophysical Profile Score.
Hemodynamic changes occurring in fetal arterial vessels during
hypoxemia and acidemia induced by uteroplacental insufficiency
Vessel
Impedance to flow
Descending aorta
Increased
Renal artery
Increased
Femoral artery
Increased
Peripheral pulmonary artery
Increased
Mesenteric arteries
Increased
Cerebral arteries
Decreased
Adrenal arteries
Decreased
Splenic arteries
Decreased
Coronary arteries
Decreased
Fetal Systemic Vascular Responses in IUGRA/REDV, absent or reversed enddiastolic velocities
HARMAN: Clin Obstet Gynecol, 46(4).December 2003.931-946
Aortic isthmus blood velocity waveform
a) normal blood flow pattern in an
uncomplicated pregnancy
b) antegrade net blood flow
(antegrade/retrograde ratio of 2.0)
c) retrograde net blood flow with a
corresponding value of 0.54 in
pregnancies complicated by placental
insufficiency.
In the sagittal view of the fetus, the aortic arch
and the location of the aortic isthmus (white
triangle) are shown.
Coronary artery blood velocity waveform of a growthrestricted 32 week fetus (heart sparing effect).
Alfred Abuhamad et al. Contemporary Ob/Gyn May 1, 2003;48:56-73
Evaluation of fetal intrapartum hypoxia by middle
cerebral & umbilical artery Doppler velocimetry with
simultaneous cardiotocography & pulse oximetry
Siristatidis C, Salamalekis E, Kassanos D, Loghis C, Creatsas G
Arch Gynecol Obstet. 2003 Nov 5
During active labor the fetus maintains oxygen
supply to the brain by redistributing blood flow. In
cases of hypoxia this is feasible for only 2 min.
Spectral Doppler waveform of an A-A anastomosis with
characteristic bidirectional, pulsatile flow.
Systematic Doppler Evaluation
HARMAN: Clin Obstet Gynecol, Volume 46(4).December 2003.931
Which Doppler Tests Should be Performed?
1.
2.
3.
4.
Uterine arteries depict maternal vascular
effects of the invading placenta
Umbilical artery Doppler reflects downstream
placental vascular resistance
Middle cerebral artery changes begin when the
redistribution of cardiac output reflects rising
placental resistance
precordial veins illustrate fetal cardiac function
DIFFERENTIAL DIAGNOSIS OF OLIGOHYDRAMNIOS
PPROM
--- normal renal vessels, normal umbilical flow & normal
filling of the bladder.
Bilateral renal agenesis or dysplasia
--- umbilical artery Doppler is normal, but no renal vessels &
no bladder filling
Severe hypoxia with IUGR
--- fetal measurements are small for gestation, fetal heart
looks dilated & the bowel is echogenic. Doppler
demonstrates the presence of two renal arteries and absent
or reversed end-diastolic frequencies in the umbilical arteries
Deficient placentation defined by notched uterine arteries
Increased umbilical artery resistance with progression to AEDV/REDV
Declining CPR, brain-sparing MCA
As the arteriovenous ratio decline, ductus venosus abnormality begins
Abnormal biophysical variables emerge
Oligohydramnios and abnormal (non-reactive) fetal heart rate tracing
Loss of fetal breathing movements, body movements and fetal tone
1. Umbilical artery Doppler should be available for assessment of the fetal-placental
circulation in pregnant women with suspected severe placental insufficiency. (I-A)
2. Depending on other clinical factors, reduced, absent, or reversed umbilical artery
end-diastolic flow is an indication for enhanced fetal surveillance or delivery. If
delivery is delayed to enhance fetal lung maturity with maternal administration of
glucocorticoid, intensive fetal surveillance until delivery is suggested for those
fetuses with reversed end-diastolic flow. (II-1B)
3. Umbilical artery Doppler should not be used as a screening tool in healthy
pregnancies, as it has not been shown to be of value in this group. (I-A)
4. Umbilical venous double pulsations, in the presence of abnormal umbilical artery
Doppler waveforms, necessitate a detailed assessment of fetal health status. (II-3B)
5. Measurement of the fetal middle cerebral artery Doppler peak systolic flow velocity
is a predictor of moderate or severe fetal anemia and can be used to avoid
unnecessary invasive procedures in pregnancies complicated with red blood cell
isoimmunization. (II-1A)
6. Since inaccurate information concerning fetal Doppler studies could lead to
inappropriate clinical decisions, it is imperative that measurements be undertaken
and interpreted by expert operators who are knowledgeable about the significance
of Doppler changes and who practise appropriate techniques. (II-1A)
THE USE OF FETAL DOPPLER IN OBSTETRICS
Society of Obstetricians and Gynaecologists of Canada. No. 130, July 2003
Conclusion

No single diagnostic modality can provide
information complete enough to adequately
address the complex nature of IUGR and its
interacting fetal compensations and compromises

Management decisions based on Doppler data
are gestational age dependent
Thank You For Your Attention!