Clinical: Placental Insufficiency Flashcards Preview

Block I: Reproduction & Sexuality > Clinical: Placental Insufficiency > Flashcards

Flashcards in Clinical: Placental Insufficiency Deck (51):
1

Size of mature placenta

  • 20 cm diameter
  • 2-3 cm thick
  • Weight 1/7th of fetus
  • Villi surface area 11-14 m2

2

Describe the shape of the mature placenta

Discoid (chorionic plate = decidual plate)

3

2 components of the fetal surface

Amnion and chorion, fetal vessels

4

2 components of the maternal surface of the mature placenta

Lobes/cotyledons and placental septae

5

4 causes of abnormal placentation

  • Maternal hyper-coagulability
  • Incomplete invasion of spiral arteries
  • Hydatidiform mole
  • Choriocarcinoma

6

4 potential consequences of maternal hyper-coagulability

  • Blood clots in the lacunae
  • Poor diffusion
  • Fetal death
  • Miscarriage (often recurrent)

7

5 potential consequences of incomplete invasion of spiral arteries (leading to abnormal placentation)

  • Placental ischemia
  • Production of ischemic/necrotic factors
  • Continued high resistance system
  • Fetal growth retardation
  • Pre-eclampsia

8

3 ischemic/necrotic factors produced due to incomplete invasion of spiral arteries

  • Soluble fms-related tyrosine kinase 1
  • Soluble endoglin
  • Decreased PIGF

9

7 potential consequences of pre-eclampsia

  • HTN
  • Proteinuria
  • Edema
  • Fetal growth retardation
  • Cerebral edema -- fitting/seizures
  • Still-birth
  • Maternal death

10

How to diagnose defective placentation

Uterine artery Doppler waveforms

  • High resistance to maternal circulation characterized by notching

11

Define intra-uterine growth retardation/restriction (IUGR)

  • Fetal growth failing (arising from maternal, placental, or fetal origins)
  • Birth weight lower than expected in the suitable gestational week

12

Dynamic definition of IUGR

Delay of the growth of the fetus estimated as a decrease of 25 centiles in the measure of the abdominal circumference, according to the standard curve at the gestational age, and in subsequent echographic evaluations performed at least every 2 weeks

13

2 classes of IUGR

Asymmetrical

Symmetrical

14

Define asymmetrical IUGR

Late onset (around 30 weeks) where abdominal growth is more affectedthan head circumference

15

Define symmetrical IUGR

Early onset (beginning of second trimester) where there is proportional lagging of the head circumference, abdominal circumference, and long bone growth

16

3 fetal risk factors for IUGR

  • Chromosomal abnormalities
  • Structural malformations (especially cardiac malformations)
  • Fetal infections

17

3 chromosomal abnormalities that have a risk for IUGR

  • Triploidy
  • Trisomy 13 and 18

18

4 fetal infections that have a risk for IUGR

  • TORCH
  • Parvovirus B19
  • Syphilis
  • Listeriosis

19

5 placental risk factors for IUGR

  • Abnormalities of the placentation
  • Acute atherosis
  • Obliteration of small muscular arteries of the tertiary villi
  • Confined placental mosaicism
  • Chorioangioma

20

Abnormality of the placentation that may cause IUGR

Reduction of number of thin-walled, distended uteroplacental vessels

21

10 maternal risk factors for IUGR

  • Low socioeconomic status
  • Chronic maternal under nutrition
  • Malnutrition (anorexia nervosa, bulimia)
  • CVD (cardiac failures, HTN, pre-eclampsia)
  • Gestroenteric diseases (chronic enteritis, malabsorption)
  • Pulmonary diseasees (CF, asthma, resp failure)
  • Renal diseases
  • Anemia
  • Alcohol and drug abuse, smoking
  • Uterine abnormalities (fibroids, uterine malformations)

22

Approx 25% of women with unilateral persistant notch and 50% of those with bilateral notch on doppler exam of uterine arteries will have what 2 conditions?

  • IUGR fetus
  • Develop pre-eclampsia
  • Experience both

23

Doppler exam findings on umbilical arteries for fetuses with IUGR

Reduced blood flow pattern during diastole

24

5 signs of fetal compromise

  • Gradually increasing resistance to blood flow in umbilical arteries
  • End distolic component may disappear or may reverse
  • Redistribution of blood flow occurs
  • Brain, heart and adrenal glands preferentially perfused
  • MCA blood flow increases

25

Define brain sparing

Cerebroplacental ratio is below 2SD prior to abnormal CTG recordings about a couple days to 2 weeks

26

Condition that brain sparing phenomenon is assocaited with

Fetal hypoxia

NOTE: When resistance in MCA begins to rise, cerebral edema occurs

27

7 tests of placental function

  • Maternal weight
  • Uterine growth - fundal height
  • Fetal body movements
  • Fetal growth (US)
  • Fetal activity (biophysical profile, non-stress test)
  • Color doppler studies
  • Placental biochemical tests

28

Most important indication of placental function

Fetal well-being (i.e. "kick count" or how long it takes for the fetus to move 10 times)

29

2 methods of assessing fetal activity

  • Non-stress test (Cardiotocography)
  • Biophysical profile

30

Describe the non-stress test

Continuous record of FHR over a period of 30 min or more. Includes recording of changes in FHR variability (from beat to beat) in association with fetal movements and uterine contractions

31

Describe the biophysical profile

A score based on real time ultrasound observation of fetal breathing, gross body movements, tone and amniotic fluid volume

32

Define hydatidiform mole

Benign trophoblastic disease with overactive trophoblast/reduced resistance.

Accumulation in villi before circulation --> distension/swelling --> fetus dies and is resorbed

33

Define still birth

Dead fetuses or newborns weighing >500 gm or >20 weeks gestation

34

4 signs of still birth

  • Absence of uterine growth
  • Loss of fetal movement
  • Absence of fetal heart
  • Disappearance of the signs & symptoms of pregnancy

35

2 x-ray findings of still birth/IUFD

  • Spalding's sign
  • Robert's sign

36

4 fetal causes of still birth (IUFD) (25 - 40%)

  • Chromosomal anomalies
  • Birth defects
  • Non-immune hydrops
  • Infections

37

7 placental causes of IUFD (still birth) (25 - 35%)

  • Abruption
  • Cord accidents
  • Placental insufficiency
  • Intrapartum asphyxia
  • Placental previa
  • Twin to twin transfusion S
  • Chorioamnionitis

38

14 maternal causes of IUFD (still birth) (5 - 10%)

  • Antiphospholipid antibody
  • DM
  • HPT
  • Trauma
  • Abnormal labor
  • Sepsis
  • Acidosis/Hypoxia
  • Uterine rupture
  • Postterm pregnancy
  • Drugs
  • Thrombophilia
  • Cyanotic heart disease
  • Epilepsy
  • Severe anemia

39

6 potential aspects of family history for still birth (IUFD)

  • Recurrent abortions
  • VTE/PE
  • Congenital anomalies
  • Abnormal karyotype
  • Hereditary conditions
  • Developmental delay

40

10 maternal medical conditions that may be found in a history for IUFD (still birth)

  • VTE/PE
  • DM
  • HPT
  • Thrombophilia
  • SLE
  • Autoimmune disease
  • Severe anemia
  • Epilepsy
  • Consanguinity
  • Heart disease

41

6 potential findings of past OB history for IUFD (still birth)

  • Baby with congenital anomaly/hereditary condition
  • IUGR
  • Gestational HPT with adverse sequelae
  • Placental abruption
  • IUFD
  • Recurrent abortion

42

9 potential findings of current pregnancy when taking history for IUFD (still birth)

  • Maternal age
  • Gestational age at fetal death
  • HPT
  • DM/gestational D
  • Smoking, alcohol, or drug abuse
  • Abdominal trauma
  • Cholestasis
  • Placanetal abruption
  • PROM or prelabor SROM

43

8 potential placental/cord complications when taking history for IUFD (still birth)

  • Large or small placenta
  • Hematoma
  • Edema
  • Large infarcts
  • Abnormalities in structure, length or insertion of the umbilical cord
  • Cord prolapse
  • Cord knots
  • Placental tumors

44

6 placental investigatoins in event of IUFD

  • Chorionocity of placenta in twins
  • Cord thrombosis or knots
  • Infarcts, thrombosis, abruption
  • Vascular malformations
  • Signs of infectoin
  • Bacterial culture for E coli, Listeria, gp B strep

45

7 places specimen for karyotype fetal investigation can be taken

  • Cord blood
  • Intracardiac blood
  • Body fluid
  • Skin
  • Spleen
  • Placental wedge
  • Amniotic fluid

46

Complication of IUFD

Hypofibrinogenemia

47

3 abnormal placental invasions

  • Placenta accreta
  • Placenta increta
  • Placenta percreta

48

Define placenta accreta

Chorionic villi attach to the myometrial cells

49

Define placenta increta

Placenta penetrates the myometrium

50

Define placenta percreta

Placenta penetrates through the serosal surface

51

3 cancers that may cause placental metastases, although very rare (immunoprotective effect)

  • Malignant melanoma
  • Breast cancer
  • Leukemias