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Flashcards in Fetal complications Deck (60):
1

Defined as a fetus weighing below the 10th percentile for gestational age

Intrauterine growth retardation IUGR/ Fetal growth restrictions

2

The most accurate dating of a pregnancy is by the first trimester ________ _________ _______or a firmly known _______ _______ __________ ___________

Crown rump length, or a firmly known last menstrual period date

3

There are many causes of IUGR with most of them relating to conditions related to the __________, _________, and ________ __________ _________

Uterus, placenta, and placental transfer rate

4

A decreasing uterine plasma volume is thought to be a ________ physiologic factor in IUGR

Major

5

What will happen to the developing fetus when it does not receive enough nutrition to provide for normal metabolic needs?

It won't grow

6

Maternal conditions which may affect uterine plasma volume

Poor nutritional status
Smoking, drug or alcohol abuse
Multiple gestation
severe anemia
Diabetes
Torch infection
Chronic renal disease
Severe chronic asthma
RH sensitization
Extremes of age under 17 or over 35
High altitude
Heart disease

7

Placental conditions which may affect uterine plasma volume

Placental infarcts and hamangiomas/ chorioangiomas
Small placenta
Single umbilical artery
Abruption
Placental insufficiency

8

Fetal conditions which may affect uterine plasma volume

Chromosomal or genetic abnormalities
Intrauterime infection

9

Growth restricted fetuses are born with diminished stores of fat and glycogen and therefore, likely to be _________

Hypoglycemic

10

Nutritional support is needed until the infant ____________ it's glycogen and fat deposits

increases

11

Clinical signs or IDGR include?

Uterus measuring small for dates
History of maternal condition which is associated with IUGR

12

IUGR can be ___________ or __________

Symmetric or asymmetric

13

Accounts for 25%
Less common
Affects the entire fetus
Etiology is often genetic or due to maternal infection
Onset may be earlier in gestation

Symmetric IUGR

14

Sono findings for Symmetric IUGR

All measurements are more than two wks below expected in the 2nd trimester or below three wks in the 3rd trimester
(remember the 1, 2, 3 rule about size in 1st, 2nd, and 3rd trimester)
Oligohydramnios
Low biophysical profile score

15

What are the two things that all measurements are based on?

either a firm LMP date or on a first trimester ultrasound

16

The __________ ___________ is usually consistent with dates when the other parameters are less than expected

transcerebellar diameter

17

Accounts for 75% or the vast majority of intrauterine growth retardation
Occurs usually in the last 8-10 wks of pregnancy

Asymmetric IUGR- brain sparing IUGR

18

____________ patterns in the fetus attempt to protect the fetal brain so it receives most of the nutrient rich blood first, and as a result, there is __________ between the head size and the abdominal size

Hemodynamic, Asymmetry

19

Ultrasound findings for Asymmetric IUGR

-The head to body ratio for HC/ AC ratio is greater than two standard deviations above normal
-The abdominal circumference measures greater than two weeks behind the head circumference
- Oligohydramnios
**The head is of normal size and the abdomen is smaller

20

What Doppler technique has been proven as diagnostic for IUGR?

There is no single Doppler technique that has been proven as a diagnostic for IUGR

21

The predictive value of Doppler in IUGR has been shown to be, ?

low, 20-40%

22

Measurements of _________ ____________ resistance are the most widely accepted

Umbilical artery

23

Normally, there is a progressive decrease in the resistance in the umbilical artery during the course of

Pregnancy

24

Why is the umbilical artery low during pregnancy?

to make it easy for the fetus to get rid of wastes back to the placenta

25

Resistive index should be

less than 0.8

26

Systolic/ diastolic ratio greater than ______is considered abnormal after _______ wks

3.0, 30

27

Ratios can be higher if measured closer to the fetal cord insertion so they should be taken closer to the

Placental cord insertion

28

Absent or reverse flow in the umbilical artery is an

ominous sign

29

What is the proper technique to measure the resistance and the systolic/ diastolic ratio

have an angle of insonation as close to zero with respect to the umbilical artery (as parallel as possible to the artery)

30

Destruction of fetal red blood cells by antibodies with subsequent fetal or neonatal complications

Erythoblastosis fetalis

31

What are the causes of Erythroblastosis fetalis

RH incompatibility
ABQ incompatibility
Iso immune disease
other minor blood group incompatibilities

32

What are the clinical manifestations for erythroblastosis fetalis?

Congestive heart failure
Fetal death
Hydrops fetalis

33

An excessive accumulation of fluid in fetal tissues and body cavities. Interstitial edema, plural and pericardial effusion's and ascites

Hydrops fetalis

34

Name the two types of hydrops

Immune hydrops
Nonimmune hydrops

35

-Secondary to Rh incompatibility (Rh isoimmunization)
-Occurs when Rh negative mother and an Rh positive father have a baby
-The fetus is Rh positive
-Maternal antibodies recognize Rh antigens on fetal blood cells as foreign

Immune hydrops

36

The maternal antibodies attack and destroy __________

Red blood cells

37

What does the destruction of red blood cells result in?

Erythroblastocysts fetalis
Fetal anemia, which results in hydrops

38

Fetal red blood cells generally do not cross the placenta so exposure of fetal cell to maternal circulation occurs at

Delivery,
abortion,
placental abruption,
hemorrhage, amniocentesis

39

During which pregnancy does the most trouble occur, due to maternal antibodies?

In the second pregnancy due to prior blood mixing after delivery of the first baby

40

What is given to the mother after each pregnancy and also after amniocentesis to prevent antibodies from forming, and to protect future pregnancies?

RhoGAM or Rh isoimmunization

41

Middle cerebral artery Doppler can help determine the likelyhood of ?

Fetal anemia

42

The MCA (middle cerebral artery) is examined close to its origin from the ?

Internal carotid artery

43

When measuring the MCA Doppler at what angle of the ultrasound beam and the direction of blood flow be?

0 degrees

44

The risk of anemia is highest in fetuses with a pre-transfusion peak systolic velocity of _______ times the median or higher

1.5

45

True or False
The fetal heart is pumping with a higher velocity and often, a higher rate in an effort to get oxygen to the tissues. Because the number of red blood cells is low, due to destruction the body compensates by doing this.

True

46

Red blood cell destruction

Hemolysis

47

A byproduct of the destruction of red blood cells

Bilirubin

48

The patient may need serial amniocentesis to determine if ____________ is occurring by testing the bilirubin levels in the amniotic fluid.

Hemolysis

49

What is more accurate for fetal anemia to determine if hemolysis is occurring?

Cordocentesis or percutaneous blood sampling (PUBS)

50

Intrauterine transfusions using ultrasound guidance can be performed to treat ___________, ideally after the onset of anemia but before the onset of fetal hydrops


anemia

51

Hydrops due to any other cause besides Rh sensitization

Non-immune hydrops

52

What are the causes of Non-immune hydrops?

Cardiac anomalies/ arrhythmia
Infections like torch and fifths disease
Chromosomal abnormalities
Congenital blood disorders
Twin/twin transfusion syndrome
Abdominal or pulmonary masses which lead to venous obstruction

53

What are the Ultrasound findings in hydrops?

Pericardial effusion (earliest sign)
Ascites
Fetal skin thickening/edema/anasarca
Placental thickening >5cm in AP dimensions
Pleural effusions
Hepatosplenomegally
Polyhydramnios
Enlarged umbilical vein, >1cm

54

Occurs during the second or third trimester,

Fetal demise

55

What does the sonographic appearance of fetal demise depend on?

It depends on when after the demise the fetus is examined`

56

What are the ultrasound findings of fetal demise?

Absent cardiac activity
Exaggerated fetal position, flexion
Roberts sign
Spaulding sign
Fetal maceration
Duels sign/halo sign

57

Echogenic foci which represents gas in pulmonary vessels or in the abdomen, this is a delayed finding, occuring after a wk after demise

Roberts sign

58

Overlapping skull bones, also a delayed finding seen about a wk after demise

Spaulding sign

59

A halo seen radiographically secondary to subcutaneous scalp edema

Duels sign/ Halo sign

60

Oligohydramnios

Low biophysical profile score