Amniotic Fluid Embolism Flashcards
Define
Definition
When foetal cells/ amniotic fluid enters the mother’s blood stream and stimulates a reaction which results in cardio respiratory collapse
Epidemiology
Very rare: 1.25/ 100,000
Associated with a high mortality rate
Aetiology
There is a consistent link between maternal age and induction of labour
The maternal circulation must be exposed to foetal cells/ amniotic fluid in order for an amniotic fluid embolism to occur -> pulmonary artery spasm -> incr in pulmonary artery pressure and RVP -> hypoxia myocardial and pulmonary cap damage -> LVF and death
However, the precise underlying pathology of this process which leads to an embolism is not well understood, though suggestions have been made about an immune mediated process (anaphylactic reaction of complement cascade provoked by embolism)
Risk Factors
Induction of labour esp use of uterotonics
≥ 35 years old
Multiple pregnancy
C section
Symptoms
This occurs in labour or delivery, or within 30 minutes after delivery
‘sudden collapse after rupture of membranes’
Symptoms
- Acute onset
- Chills, feeling cold
- Shivering
- SOB, respiratory distress
- Restlessness, anxiety - sense of impending doom
- Distress and panic
- Coughing
- N+V
- Pins and needles in fingers
Signs
- Cyanosis
- Acute hypotension
- Acute hypoxia
- Bronchospasms
- Tachycardia
- Tachypnoea
- PO
- Arrhythmia
- Myocardial infarction
Coagulopathy (severe DIC) often develops
- This can result in massive PPH
- Foetal distress
Investigations
Diagnosis is usually CLINICAL- it is a diagnosis of exclusion
ABG – hypoxaemia, raised PACO2
FBC– low Hb
Clotting – ¯ platelets, PT/APTT, ¯fibrinogen, UE, X-match
CXR – cardiomegaly, pulmonary oedema
ECG – right heart strain, rhythm abnormalities
Management
This is an EMERGENCY!
ABC Approach – resuscitation and supportive care
- Resuscitate with high flow oxygen- most will need endotracheal intubation
- Fluids to maintain BP (but do NOT fluid overload) - 2 large bore cannula
- Inotrope support may be needed
- Early aggressive treatment of coagulopathy using FFP (cryoprecipitate, plts or transfusion)
- Treat uterine atony if present -> PPH management
- Measure cardiac output to help guide therapy
Early involvement with senior staff- obstetrician, anaesthetist, haematologist, intensivist - crash bleep
Delivery baby ASAP if not already delivered (consider hysterectomy)
Complications
Seizures
Cardiac arrest
LV failure
Coagulopathy
Uterine atony and PPH
ARDS
Renal fail
Prognosis
- poor
- Of those who die, 25% die in first hour
