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Flashcards in Abnormal Fetal Growth Deck (45)
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1

Standard Routine Measurements

Biparietal diameter (BPD)
Head circumference (HC)
Abdomen circumference (AC)
Femur length (FL)

2

Head Measurements

BPD
HC
Cephalic index (CI)
Transverse Cerebellum
Binocular

3

Criteria for BPD

CSP (Cavum septum pellucidum) & thalamus
No cerebellum
Hemispheres symmetrical
Ultrasound beam 90 degrees to midline echo
Calipers placed at widest part of skull

4

IUGR vs SGA

DO NOT confuse IUGR with term small for gestational age (SGA).
SGA describes fetus with weight below 10th percentile without reference to cause.
Fetal growth restriction describes subset of SGA fetuses with weight below 10th percentile as result of pathologic process from variety of maternal, fetal, placental disorders.

5

Symmetric IUGR

All measurements small (BPD, HC, AC, FL)
genetic disorders (e.g., trisomy 18), fetal infections (e.g., rubella and cytomegalovirus), congenital malformations, and a variety of syndromes (e.g., Cornelia de Lange)

6

Asymmetric IUGR

Head measurements correlate with age (BPD, HC)
Other measurements small (AC, FL)
relative nutritional and oxygen deprivation

7

Prenatal effects of IUGR

Increased mortality
Decrease in umbilical vein volume
Decreased cardiac output
Increased cerebral circulation
Heart failure

8

Postnatal effects of IUGR

Increased
Short and long term morbidity
Learning disabilities
Behavioral problems
Reduced cognitive function
High blood pressure
Diabetes
Acquired heart disease

9

Maternal risk factors with IUGR

Low socioeconomic status/ poor maternal nutrition
Coexisting maternal disease, infection or genetic disorder incl:
Collagen vascular disease ( i.e. systemic lupus erythematosus)
Chronic and severe renal cardiovascular or respiratory diseases
Hypertension and preeclampsia
Diabetes Antiphospholipid antibody syndrome
Inflammatory bowel disease
Lung disease
Sickle cell anemia
Maternal drug use/teratogenic exposure
Hx of child of unexplained low birth wt.
Hx of IUGR pregnancy
Hx. Preterm birth

10

Fetal risk factors with IUGR

Aneuploidy
Congenital infections ( CMV, varicella zoster)
Genetic syndromes
Congenital anomalies
Monochorionic twins
Twin to twin transfusion
Higher order multiples

11

Placental risk factors of IUGR

Placental abruption
Placenta previa
Marginal or velamentous umbilical cord insertion
Placental neoplasms
Circumvillate placenta
Advanced placental grade
Placental mosaicism

12

weight-based theories

Low birth weight
Varies with gestational age
IUGR
Borderline at 25%
Diagnosed at 10%

13

weight-based theories requirements

Gestational age
Estimated fetal weight (EFW) calculation
BPD, AC (Shepard)
HC, AC, FL (Hadlock)
Gestational age (weeks), HC, AC (multiplied by 2), FL (Sabbagha)
Third trimester measurements

14

echogenic bowel can indicate

Pathology

15

Doppler fetus IUGR

redistribution of blood within the fetus and placenta

16

what factors affect the fetal spectral waveform

-patient position
-fetal/maternal breathing
-fetal cardiac abnormalities
-maternal ingestion of pharmacologic agents

17

umbilical artery

normal-low resistance above the baseline
Abnormal-high resistance with no or little end-diastolic flow, possible flow reversal

18

Cerebral blood flow

Normal pregnancy there is continuous forward flow in the fetal MCA
MCA is the main lateral branch of the circle of Willis
High resistance circulation results in a high Doppler reading in a normal fetus (this is opposite of the case in other fetal vessels)
With fetal growth restriction, there is a marked decrease in cerebral resistance - Results in a low Doppler ratio

19

what occurs with growth restriction

Blood will be shunted towards the brain, which will change the MCA from being high resistant to low resistant and will have a low Doppler ratio

20

what will occur in hypoxia

Blood will be shunted towards the braian, the heart and the adrenal gland

21

with compensation, during diastolic

will see increased blood flow

22

Uterine Artery Doppler

Uterine artery travels along the lateral aspect of the uterus from the level of the cervix
Most readily identifiable location for sampling the uterine artery with u/s is at the level of the cervix
In non pregnant women & early pregnancy ut artery has a notch at the beginning of the diastolic phase of the cardiac cycle
In the 2nd / 3rd trimester the presence of a notch or persistently elevated ratios – pregnancy may suffer inadequate nutrition or O2- this can lead to pre eclampsia and IUGR

23

Macrosomic

Weight greater than 4200-4500 grams regardless of the GA

24

Large for Gestational Age

LGA refers to a fetus or infant who is larger than expected for the age and gender. It can also mean an infant with a birth weight above the 90th percentile.

25

large for gestational age complications

A baby that is large for gestational age has a higher risk of birth injury.
There is also a risk of complications of low blood sugar after delivery (if the LGA is due to maternal diabetes).

26

Common causes of large for Gestational age

Gestational diabetes
Prolonged pregnancy
Erythroblastosis fetalis
Some non chromosomal genetic syndromes (e.g., Beckwith-Weidemann synrome)

27

what is APGAR

Apgar is a quick test performed on a baby at 1 and 5 minutes after birth.

The 1-minute score determines how well the baby tolerated the birthing process.

The 5-minute score tells the doctor how well the baby is doing outside the mother's womb.

In rare cases, the test will be done 10 minutes after birth.

28

what are the five components of APGAR score

Breathing effort
Heart rate
Muscle tone
Reflexes
Skin color

Each category is scored with 0, 1, or 2, depending on the observed condition.

29

Biophysical components

Nonstress test (NST)
Fetal
Breathing
Movements
Tone
Qualitative amniotic fluid volume

30

fetal movement

2 points if three or more discrete body or limb movements within 30 minutes of observation