Background
- Obstetric emergency often presenting as sudden, profound and unexpected maternal collapse associated with hypotension, hypoxaemia and DIC
- Majority die within an hour of symptom onset
- Also a major cause of neonatal morbidity and mortality (high as 70%)
- Caused by amniotic fluid/foetal cells enter the maternal circulation
- Rare (between 1 in 8000 and 1 in 80000 pregnancies) but still accounts for ~5% of maternal deaths in the UK
- Most occur during labour (70%); 19% in C-section and 11% following vaginal delivery (can also be caused by procedures such as amniocentesis, although this is actually a rare cause)
Risk factors
- A few things seem to be associated (not proven)
- Advanced maternal age
- Multiparity
- Meconium stained liquor
- Intrauterine foetal death
- Polyhydramnios
- Strong, frequent or tetanic uterine contractions
- Maternal history of allergy/atopy; chorioamnionitis; microsomia; uterine rupture and placenta accreta
Pathophysiology
- Amniotic fluid increases the systemic and pulmonary resistance leading to acute pulmonary hypertension, with associated left ventricular failure and pulmonary oedema.
- Accompanied by pulmonary vasospasm, hypoxia is often profound (may lead to ARDS)
Presentation
- Maternal collapse, breathlessness, cyanosis, hypotension, dysrhythmias, DIC
- May be preceded by foetal distress and sudden chills, shivering, sweating, anxiety, and coughing followed by signs of respiratory distress, shock, cardiovascular collapse, and convulsions
- Other milder signs may include cough, headache, chest pain
Management
- Often clinical diagnosis
- Even where the diagnosis has not been confirmed- oxygen therapy, CPR if required and DELIVERY
- Plasma transfusion may be appropriate
Notes on Medicine/Surgery 