Red - Amniotic Fluid Embolus

Question 1

Define AFE

Answer 1

Rare

Catastrophic

Obstetric Emergency

Present with sudden maternal collapse.

Associated with hypoxaemia
Shock
Coagulopathy

Occurs when fetal cells enter maternal circulation

Question 2

Incidence of AFE

Answer 2

1-12 per 100,000

Question 3

Pathophysiology of AFE

Answer 3

Initially thought to be fetal cells physically blocking maternal circulation as emboli

But now two phase immune repsone:

1 - Fetal tissue antigens –> release vasoactive substances

Pulmonary artery vasospasm --> acute RHF, hypotension and hypoxia

Lasts 30 mintutes

2 - RV recovers, LVF, pulmonary oedema. Severe hypoxaemia and mediatorys –> increased cap permeabiltiy, DIC, uterine atony, MOH

Question 4

Clinical features of AFE

Answer 4

TRIAD

Hypoxaemia - breathlessness, cyanosis
Cardiovascualr Collapse - hypotnesion, dysrhythmia,
Coagulopathy - DIC

Sudden maternal collapse

May be non specific

Question 5

Risk factors for AFE

Answer 5

Advanced maternal age
Placenta patholgoy - abruption/praevia
IOL
Operative delviery
Multiparity
Polyhydramnios
Uterine rupture
IUD
Trauma (lacerations)

Question 6

Differential diagnosis of AFE

Answer 6

Obstetic:
   Placental abruption
   Eclampsia
   Uterine ruptutre
   PPH

Non-
    Anaphyaxis
    Total spinal
     Sepsis
     PE

Question 7

Managing AFE

Answer 7

1) its supportive
2) ABCDE

Principles: early recognition
prompt resus
expedite delviery of fetus

1) Left lateral tilt
2) Rapid iv resus and direct acting vasopressors
3) Delivery fetus
4) Activate major haemorrhage protocol
Surgical intervention for haemorrhage control
Maintain uterine tone - synto, ergometrine, prostaglandi

5) invasice monitoring but beware consumptaive coagulapathy