Intrapartum Care: Amniotic Fluid Embolus, Uterine Rupture & Uterine Inversion

Question 1

What is an amniotic fluid emoblism?

Answer 1

A rare but severe condition where the amniotic fluid passes into the mother’s blood. This usually occurs around labour and delivery.

The amniotic fluid contains fetal tissue, causing an immune reaction from the mother.

This immune reaction to cells from the fetus leads to a systemic illness.

It has more similarities to anaphylaxis than venous thromboembolism.

Question 2

Mortality rate of amniotic fluid embolism?

Answer 2

> 20%

Question 3

What are the 2 key risk factors for amniotic fluid embolus?

Answer 3

1) increasing maternal age

2) induction of labour

Question 4

When does amniotic fluid embolism usually present?

Answer 4

Amniotic fluid embolisation usually presents around the time of labour and delivery, but can be postpartum.

Question 5

Presentation of amniotic fluid embolisation?

Answer 5

It can present similarly to sepsis, pulmonary embolism or anaphylaxis, with an acute onset of symptoms of:

1) Chills
2) Shivering
3) Sweating
4) Anxiety
5) Coughing

Signs:
1) SOB
2) Hypoxia
3) Hypotension
4) Coagulopathy
5) Haemorrhage
6) Tachycardia
7) Confusion
8) Seizures
9) Cardiac arrest

Question 6

Management of amniotic fluid embolism?

Answer 6

Supportive (no specific treatments).

Medical emergency - likely transferral to ICU.

ABCDE approach:
A – Airway: Secure the airway
B – Breathing: Provide oxygen for hypoxia
C – Circulation: IV fluids to treat hypotension and blood transfusion in haemorrhage
D – Disability: Treat seizures and consider other neurological deficits
E – Exposure

Question 7

What is uterine rupture?

Answer 7

A complication of labour, where the muscle layer of the uterus (myometrium) ruptures.

Question 8

What are the 2 main types of uterine rupture?

Answer 8

1) Incomplete

2) Complete

Question 9

What is an incomplete uterine rupture (or uterine dehiscence)?

Answer 9

Where the uterine serosa (perimetrium) overlying the uterus remains intact.

In this case, the uterine contents remain within the uterus.

Question 10

What is a complete uterine rupture?

Answer 10

The serosa ruptures along with the myometrium, and the contents of the uterus are released into the peritoneal cavity.

Question 11

What are some risk factors for uterine rupture?

Answer 11

Risk factors that generally make the uterus inherently weaker:

1) Previous c-secton (greatest risk factor for uterine rupture)

2) Previous uterine surgery e.g. myomectomy

3) Induction - (particularly with prostaglandins) or augmentation of labour.

4) Obstruction of labour: important risk factor to consider in developing countries.

5) Multiple pregnancy

6) Multiparity

Question 12

What is the greatest risk factor for uterine rupture?

Answer 12

Previous c-section

Question 13

What incision in c-section carries the highest risk for uterine rupture?

Answer 13

Classical (vertical) incisions.

Question 14

Clinical features of uterine rupture?

Answer 14

Non-specific, which makes diagnosis and prompt management difficult.

1) Sudden & severe abdo pain (most common presenting symptom)
- pain persists between contractions

2) May also experience shoulder-tip pain (from diaphragmatic irritation)

3) May have vaginal bleeding.

4) May be signs of significant haemorrhage & hypovolaemic shock:
- tachycardia
- hypotension.

5) Ceasing of uterine contractions

Question 15

On examination, what may be seen in uterine rupture?

Answer 15

There may be regression of the presenting part, with abdominal palpation revealing scar tenderness and palpable fetal parts.

Question 16

What are the 3 main differentials to consider in uterine rupture?

Answer 16

1) Placental abruption:
- presents with abdominal pain +/- vaginal bleeding
- uterus is often described ‘woody’ and tense on palpation.

2) Placenta praevia:
- typically causes a painless vaginal bleeding.

3) Vasa praevia:
- characterised by a triad of ruptured membranes, painless vaginal bleeding, and fetal bradycardia.

Question 17

What is a key investigation in women at risk of uterine rupture?

Answer 17

Intrapartum monitoring with cardiotocography (CTG) is vital.

Question 18

What are early foetal indicators for uterine rupture?

Answer 18

1) Changes in fetal heart rate pattern (such as recurrent or late decelerations)

2) Prolonged fetal bradycardia

Question 19

Management of uterine rupture?

Answer 19

Obstetric emergency.

In many cases, a pathological CTG prompts an emergency section – with uterine rupture noted intra-operatively.

Question 20

If there is a suspicion of uterine rupture in the pre-labour setting, what investigation can be done?

Answer 20

US for diagnosis

Question 21

What features may be seen on an US in uterine rupture?

Answer 21

• abnormal fetal lie or presentation
• haemoperitoneum
• absent uterine wall

Question 22

What should the decision-incision interval in operative intervention in uterine rupture be?

Answer 22

<30 minutes

Question 23

What is uterine inversion?

Answer 23

A rare complication of birth, where the fundus of the uterus drops down through the uterine cavity and cervix, turning the uterus inside out.

It is a very rare occurrence, and you are unlikely to see one in your career unless you become a midwife or obstetrician.

It is a life-threatening obstetric emergency.

Question 24

What are the 2 types of uterine inversion?

Answer 24

1) Incomplete (partial)

2) Complete

Question 25

What is an incomplete (partial) uterine inversion?

Answer 25

Where the fundus descends inside the uterus or vagina, but not as far as the introitus (opening of the vagina).

Question 26

What is a complete uterine inversion?

Answer 26

Involves the uterus descending through the vagina to the introitus.

Question 27

What may uterine inversion be the result of?

Answer 27

May be there result of pulling too hard on the umbilical cord during active management of the third stage of labour.

Question 28

Presentation of uterine inversion?

Answer 28

Uterine inversion typically presents with a large postpartum haemorrhage. There may be maternal shock or collapse.

Exam:
- An incomplete uterine inversion may be felt with manual vaginal examination.
- With a complete uterine inversion, the uterus may be seen at the introitus of the vagina.

Question 29

What are the 3 management options for treating uterine inversion?

Answer 29

1) Johnson manoeuvre

2) Hydrostatic methods

3) Surgery

Question 30

What is the Johnson manoeuvre?

Answer 30

1) Involves using a hand to push the fundus back up into the abdomen and the correct position.

2) The whole hand and most of the forearm will be inserted into the vagina to return the fundus to the correct position.

3) It is held in place for several minutes, and medications are used to create a uterine contraction (i.e. oxytocin).

4) The ligaments and uterus need to generate enough tension to remain in place.

Question 31

When the Johnson manoeuvre fails in uterine inversion management, what is then used?

Answer 31

Hydrostatic methods

Question 32

What are hydrostatic methods in uterine inversion?

Answer 32

This involves filling the vagina with fluid to “inflate” the uterus back to the normal position.

It requires a tight seal at the entrance of the vagina, which can be challenging to achieve.

Question 33

Where both the Johnson manoeuvre and hydrostatic methods fail, what is the next step in management of uterine inversion?

Answer 33

Surgery –> a laparotomy is performed (opening the abdomen) and the uterus is returned to the normal position.