Doppler in Obstetrics

Farhan Hanif,MD

Maternal Fetal Medicine

• Doppler assessment of the placental and fetal circulation is important tool screening for adverse pregnany outcomes

Arch of the aorta

Foramen ovale

Inferior vena cava

Ductus venosus

Umbilicus

Umbilical vein

Umbilical arteries

Aortic isthmus

Coronary arteries

Pulmonary artery

Hepatic/Splenic

Common iliac artery

Common iliac artery

Br Heart J 1994;71:232-237.

Tricuspid valveMitral valve

MCA

Angle Dependence

Rizzo et al. Ultrasound Obstet Gynecol 1996;7:401-410.

Schematic Representation of Velocity Waveformsof the Inferior Vena Cava and Ductus Venosus

SD

A

Inferior Vena Cava% reverse flow = TVI reverse flow/TVI forward flow x 100

Pre-load index (PLI) = PV A/PV S

S/D = PV S/PV D

S/D TVI = TVI S/TVI D

PVIV = (PV S - PV A)/PV D

PIV = (PV S - PV A)/mean velocity

Ductus VenosusSD

A

S/A = PV S/PV A

Pre-load index (PLI) = (PV S - PV A)/PV S

PVIV = (PV S - PV A)/PV D

PIV = (PVS - PV A)/mean maximum velocity

Doppler in IUGR

• EFW<10th %ile

• EFW <2SD above the mean

• EFW <5th %ile

• AC <5th %ile

• ACOG defines IUGR as EFW <10thile

Compensatory Mechanisms

MCA PI

Echogenic Bowel

AF

Fetal Hypoxemia- placental insufficiency

Blood flow Redistribution

Brain, heart, adrenal Gland

Lung, kidney, bowel

UA

Abnormal Venous Doppler

Abnormal Venous Doppler

Myocardial dysfunctionMyocardial dysfunction

Pressure in Rt Atrium / Dilatation of DV

Pressure in Rt Atrium / Dilatation of DV

Decompensation

Fetal Hypoxemia / AcidosisFetal Hypoxemia / Acidosis

Abnormalities in Central Control of FHR

“ANS” or Direct Myocardial Depression

Abnormalities in Central Control of FHR

“ANS” or Direct Myocardial Depression

Variability Baseline Deceleration

Umbilical artery

Abnormal Umbilical vein

Abnormal Umbilical vein

Abnormal Umbilical artery

MCA waveformsA = Normal

B = “Brain sparing effect”

Normal

Brain Sparing

MCA Doppler In Anemia

• In Anemic fetuses, the PSV will inrease.

• Obtaining PSV at 0 degrees angle is important in anemic fetuses.

• Increase False positive rate after 34 weeks

IUGR

AGA

IUGR

S D

a

Role of Ductus Venosus

Baschat et al ultrasound obstet gynecol 2004

0

5

10

15

20

25

30

35

40

45

Groups

DV Normal

UA A/REDF

DV Abn

DV A/REDF

Temporal Sequence of Cardiovascular changes in

IUGR fetuses

Ferrazi et al. US Obstet Gynecol 2002; 19: 140-6

Doppler Indices and outcomes

• In complicated pregnancies abnormal Doppler indices are powerful predictors of adverse perinatal outcome;

Low Apgar scoreNonreassuring fetal status Low pHPresence of thick meconiumAdmission to NICU

Doppler Indices and outcomes

• Reduce perinatal death and unnecessary induction of labor in the preterm growth restricted fetus.

• A meta-analysis use of Doppler ultrasonography reduced the odds of perinatal death by 38 percent (95% CI 15-55)

Alfirevic Z et al Am J Obstet Gynecol 1995

Umbilical Artery

• Absence or reversal of end-diastolic flow in the umbilical artery is suggestive of poor fetal condition, whereas normal or slightly decreased umbilical Doppler flow is rarely associated with significant morbidity

Ott WJ J Ultrasound Med 2000

IUGR

Serial Growth Scan 4 weeks intervalDoppler UA and MCA every 1-2 weeksEvaluate MCA at term

Doppler UA and MCA

If Normal

Repeat Doppler in 1-2 weeks

If normal

?APFSConsider Delivery at 39 weeks

EDF

Abnormal Doppler UA and MCA

PresentDV Normal

Growth Scan 2-4 wksWeekly UA, MCA,+/-DV

May follow as outpatientBMZ,APFS

Consider Delivery at 35-37 weeks

Absent/Reverse

Admit Steroids NST q shift and daily BPP

Deliver at 32-34wks Abnormal APFS

DV EDFPresent Ab/Reverse

Admit Steroids Continuous monitoring

?Timing of Delivery

EGA

>30weeks

Deliver

<30weeks

Continuous Monitoring Daily BPPDaily DopplerEvaluate AoA, Valves

Deliver for Abnormal BPP,FHT?Reversed AoA,E:A Ratio

Absent or Reversed Flow in the Ductus Venosus

Doppler in AGA Fetuses

• Routine screening with dopplers in AGA fetuses is controversial

• However, abnormal UA identifies the fetuses at risk in uncomplicated pregnancies as

DM Ch HTNSLE

Maternal autoimmune Twins Postterm

Uterine Artery Doppler

First trimester

Early 2nd Trimester

Late 2nd trimester

Uterine Artery Doppler

Outcome Sensitivity Specificity NPV

PE 78 95 99

IUGR <10 23 95 96

IUGR <3 36 96 92

Prediction of PE

Study n Condition Outcome

McParland et al 100 PE ASA 2%, P 19%

Bower et al 60 Severe PE ASA 13%, P 38%

Morris et al 102 PE ASA 8%, P 14% (NS)

Prevention

Uterine Artery in 1st trimester

7797 women with singleton pregnancies at 11 to 13 weeks. In 34 women , at < 34 weeks. At a 5% FPR; The sensitivity 94.1 percent The specificity was 94.3 percent

Doppler in first Trimester

• Increases the sensitivity of first trimester screening and decreases the false postivie rate

• DV reversed flow in DV in first trimester is a risk factor for CHD even in the presence of normal NT

• Can be used as a part of risk calculation for stillbirth

• CAN be used as a tool to