Obstetrics - Amniotic Fluid Embolus

Question 1

Define AFE

Answer 1

RareCatastrophicObstetric EmergencyPresent with sudden maternal collapse.Associated with hypoxaemia Shock CoagulopathyOccurs 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 emboliBut now two phase immune repsone:1 - Fetal tissue antigens –> release vasoactive substances Pulmonary artery vasospasm –> acute RHF, hypotension and hypoxiaLasts 30 mintutes2 - RV recovers, LVF, pulmonary oedema. Severe hypoxaemia and mediatorys –> increased cap permeabiltiy, DIC, uterine atony, MOH

Question 4

Clinical features of AFE

Answer 4

TRIADHypoxaemia - breathlessness, cyanosisCardiovascualr Collapse - hypotnesion, dysrhythmia, Coagulopathy - DICSudden maternal collapseMay be non specific

Question 5

Risk factors for AFE

Answer 5

Advanced maternal agePlacenta patholgoy - abruption/praeviaIOLOperative delvieryMultiparityPolyhydramniosUterine ruptureIUDTrauma (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 supportive2) ABCDE Principles: early recognition prompt resus expedite delviery of fetus1) Left lateral tilt2) Rapid iv resus and direct acting vasopressors3) Delivery fetus4) Activate major haemorrhage protocol Surgical intervention for haemorrhage control Maintain uterine tone - synto, ergometrine, prostaglandi5) invasice monitoring but beware consumptaive coagulapathy