Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Obstetrics > Foetal Abnormalities > Flashcards

Foetal Abnormalities Flashcards

1
Q

What is breech presentation? Why is this significant?

A

When the foetus presents buttocks or feet first (rather than head in cephalic presentation).
It has significant implication in terms of delivery - especially if occurring at term (>37 weeks). Carries a higher perinatal mortality and morbidity largely due to birth asphyxia/trauma, prematurity and an increased incidence of congenital malformations.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the types of breech presentation?

A

Complete (flexed)
- both legs flexed at the hips and knees - sitting cross-legged

Frank (extended) - most common
- both legs flexed at the hip and extended at the knee

Footling
- one or both legs extended at the hip so that the foot is the presenting part

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What percentage of babies are breech at 28 weeks and what percentage are breach at term?

A

20% are breech at 28 weeks
The majority spontaneously revert to cephalic presentation
Only 3% breech at term

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What are the uterine risk factors for breech presentation?

A

Multiparity
Uterine malformations e.g. septate uterus
Fibroids
Placenta praevia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the foetal risk factors for breech presentation?

A 
Prematurity
Macrosomia
Polyhydraminos
Twin pregnancy (or higher order)
Abnormality e.g. anencephaly
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What are the clinical features of breech presentation?

A

Diagnosis made at 32-35 weeks 9as likely to revert to cephalic before)
Foetal head felt in upper part of the uterus on palpation and irregular mass (buttocks and legs) in the pelvis.
Foetal heart auscultation higher on the maternal abdomen
If not diagnosed until labour - foetal distress, meconium-stained liquor
Sacrum/foot felt through cervical opening on vaginally exam.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What are the differentials for breech presentation?

A

Oblique lie - diagonally in uterus with head/buttocks in one iliac fossa
Transverse lie - across uterus with head on one side and buttocks other (shoulder usually presenting part)
Unstable lie - presentation changes day to day, more likely if known polyhydraminos/woman is multparous.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the investigations for breech presentation?

A

USS

  • can identify the type of breech
  • can also reveal predisposing foetal/uterine abnormalities
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are the options for management of breech presentation?

A

External cephalic version
Caesarean section
Vaginal breech birth

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is external cephalic version?

A

The manipulation of the foetus to a cephalic presentation through the maternal abdomen. If successful, can attempt a vaginal delivery.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are the complications of external cephalic version?

A

Transient foetal abnormalities
More persistent heart problems e.g. foetal bradycardia (rare)
Placental abruption (rare)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

When is external cephalic version contraindicated?

A

Recent antepartum haemorrhage
Ruptured membranes
Uterine abnormalities
Previous C section

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

When is a c section indicated as management for a breech presentation?

A

If external cephalic version is unsuccessful, contraindicated or declined by the woman

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

When is vaginal breech birth indicated in breech?

A

Patient preference/presentation at labour

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the contraindications of vaginal breech delivery?

A

Footling breech (as the feet and legs can slip through a non-fully-dilated cervix and the shoulders and head can then become trapped)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What must be done hen conducting a breech vaginal delivery?

A

Hands off - putting traction on can cause foetal head extension and cause it to get trapped
Foetal sacrum should be maintained anteriorly by holding the foetal pelvis
Some manoeuvres may be needed if the baby does not deliver spontaneously (flexing foetal knees, Losvett’s manoeuvre, MSV manoevre)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the complications of breech presentation?

A

Cord prolapse (umbilical cord drops down below the presenting part and becomes compressed)
Foetal head entrapment
Premature rupture of membranes
Birth asphyxia (usually secondary to delay in delivery)
Intracranial haemorrhage (rapid compression of the head during delivery)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Define lie.

A

The relationship between the long axis of the foetus and the mother
Can be longitudinal, transverse or oblique

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Define presentation.

A

The foetal part that first enters the maternal pelvis.
Cephalic vertex presentation is the most common and safes.
Others include breech, shoulder, face and brow

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Define position.

A

The position of the foetal head as it exits the canal.
Usually the head engages occipito-anterior (occipital facing anteriorly).
Others include occipito-posterior and occipito-transverse

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the risk factors for abnormal foetal lie, malpresentation and malposition?

A 
Prematurity
Multiple pregnancy
Uterine abnormalities 
Foetal abnormalities
Placenta praevia
Primiparity
22
Q

How can the foetal lie be assessed?

A

Face the patient’s head
Place hands on either side of the uterus and gently apply pressure
One side will feel fuller and firmer (back)
Foetal limbs may feel knobbly on the opposite side

23
Q

How can the foetal presentation be assessed?

A

Face the patient’s head
Palpate the lower uterus (above the pubic symphysis) with the fingers of both hands
The head feels hard and round (cephalic)
The bottom feels soft and triangular (breech)
May be able to push the foetal head gently from side to side

24
Q

When might it not be possible to identify the foetal lie and presentation?

A

Mother has a high BMI
Full bladder
Foetus is small
Polyhydraminos

25
Q

How can the foetal position be assessed?

A

During labour, vaginal examination is used to assess the foetal head
The landmarks include the anterior and posterior fontanelles which indicate the position

26
Q

What investigations are done for abnormal foetal lie, malpresentation and malposition?

A

USS

Can also demonstrate predisposing uterine or foetal abnormalities

27
Q

What is the management for abnormal foetal lie?

A

External cephalic version can be attempted between weeks 36 and 38

28
Q

What is the management for foetal malpresentation?

A

Breech - ECV/vaginal breech delivery/C-section
Brow - C section
Face - if chin anterior - normal labour (however, can be prolonged and a c section may be necessary)
- if chin posterior - C section
Shoulder - C section

29
Q

What is the management for foetal malposition?

A

90% spontaneously rotate as labour progresses
If not - rotation and operative vaginal delivery
Alternatively - C section

30
Q

What is oligohydraminos?

A

A low level of amniotic fluid during pregnancy

Defined by an amniotic fluid index below the 5th centile for the gestational age

31
Q

What is the pathophysiology of oligohydraminos?

A

Amniotic fluid increases until 33 seeks and then plateaus (approx 500ml).
Mainly made of foetal urine output (small contributions as well from placenta and foetal secretions e.g. respiratory).
Foetusbreathes and swallows amniotic fluid, processes it, fills the bladder and is voided.
Problems with any structures in this pathway can lead to either too much or too little fluid. (Anything blocking production of urine, blocks output or cause amniotic fluid to leak - rupture of membranes)

32
Q

What is the aetiology of oligohydraminos?

A

Preterm prelabour ROM
Placental insufficiency (blood flow redeistributed to foetal brain instead of kidneys - poor urine output)
Renal agenesis (Potter’s syndrome)
Non-functioning foetal kidneys e.g. bilateral multicystic dysplastic kidney
Obstructive uropathy
Genetic/chromosomal abnormalities
Viral infections (may also cause polyhydraminos)

33
Q

How is oligohydraminos diagnosed?

A

USS

Amniotic fluid index - measure maximum cord-free vertical pocket of fluid in 4 quadrants and adding together

34
Q

What is asked about in the history of oligohydraminos?

A

Symptoms of leaking fluid and feeling damp all the time (new urinary incontinence)

35
Q

What is done on examination of oligohydraminos?

A

Measure the symphysis fundal height

Perform a speculum examination - ?pool of liquor in vagina

36
Q

What is looked for on ultrasound in oligohydraminos?

A 
Liquor volume
Structural abnormalities 
Renal agenesis
Obstructive uropathy
Measure foetal size (small babies can result from placental insufficiency)
37
Q

When would karyotyping be indicated in oligohydraminos?

A

In cases of early and unexplained oligohydraminos

38
Q

When considering ruptured membranes as a cause of oligohydraminos, what bedside test can be done?

A

Test for IGFBP-1 in the vagina.

This protein is found in amniotic fluid and if detected, is strongly suggestive of membrane rupture.

39
Q

What are the 2 most common causes of oligohydraminos?

A

Rupture of membranes

Placental insufficiency

40
Q

What is the management of ruptured membranes as a cause of oligohydraminos?

A

Labour likely to commence within 24-48 hours
If preterm rupture/labour doesnt start automatically - induce labour around 34-36 weeks (in the absence of infection)
Course of steroids given o aid foetal lung development and antibiotics to reduce the risk of ascending infection.

41
Q

What is the management of oligohydraminos caused by placental insufficiency?

A

Babies likely to be delivered before 36-37 weeks

Timing of delivery depends on rate of foetal growth, umbilical artery and MCA doppler, CTG

42
Q

What is the prognosis for oligohydraminos in the 2nd trimester?

A

Poor prognosis
Majority caused by premature ROM (may or may not be associated with infection)
Subsequent premature delivery and pulmonary hypoplasia (can cause significant respiratory distress at birth)

43
Q

What is the prognosis of oligohydraminos when it is associated with placental insufficiency?

A

Higher rate of preterm deliveries usually through planned induction of labour

44
Q

What is a complication of oligohydraminos?

A

Amniotic fluid allows the foetus to move its limbs in utero (exercise)
Without this, the foetus can develop severe muscle contractures which may lead to disability despite physio at birth

45
Q

What is polyhydraminos?

A

An abnormally large level of amniotic fluid during pregnancy.
Amniotic index above the 95th centile for gestational age.

46
Q

What is the aetiology of polyhydraminos?

A

50-60% idiopathic
Any condition preventing the foetus swallowing e.g. CNS abnormalities, muscular dystrophies, oesophageal atresia
Duodenal atresia (double bubble on USS)
Anaemia (viral infections, alloimmune disorders)
Foetal hydrops
Twin-to-twin transfusion syndrome
Increased lung secretions (cystic adenomatoid malformation of lung)
Genetic/chromosomal abnormalities
Maternal diabetes
Maternal ingestion of lithium (leads to foetal diabetes insipidus)
Macrosomia (larger babies produce more urine)

47
Q

How is polyhydrminos diagnosed?

A

USS and amniotic fluid index

48
Q

Describe the clinical assessment of polyhydraminos.

A

Palpate uterus to see if tense
USS (measure liquor volume, assess foetal size, assess foetal anatomy to detect structural causes, doppler to detect foetal anaemia)
Maternal glucose tolerance test
Karyotyping if structural abnormalities/foetus is small
TORCH screen
Maternal red cell antibodies (routinely checked at 28 weeks for all)

49
Q

What is the management for polyhydraminos?

A

No medical intervention in the majority.
If symptoms severe e.g. breathlessness - amnioreduction
Indomethacin - eater retention - reduces foetal urine output
If idiopathic - need to be examined before first feed - NG tube should be passed to ensure no trachoesophageal fistula or oesophageal atresia

50
Q

Why is amnioreduction not performed routinely?

A

It is associated with infection and placental abruption

51
Q

Why should indomethacin not be used beyond 32 weeks?

A

Associated with premature closure of the ductus arteriosis

52
Q

What is the prognosis for polyhydraminos?

A

Increased perinatal mortality due to the likely presence of an underlying abnormality/congenital malformation (1%) and an increased incidence of preterm labour (over-distension of the uterus)
Malpresentation more likely - more room to move about - careful in rupture of membranes as higher risk of cord prolapse
Postpartum haemorrhage (uterus has to contract further to achieve haemostasis)

Obstetrics (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions