Obstetric emergencies

Question 1

Features of AFE

Answer 1

- collapse during labour or delivery or within
30 minutes of delivery 
- acute hypotension, 
- respiratory distress 
- acute hypoxia

If AFE occurs prior to delivery, profound fetal distress develops acutely.

Question 2

Phases of progression of AFE

Answer 2

1. vascular occlusion either by debris or by vasoconstriction
2. pulmonary hypertension
3. left ventricular dysfunction or failure develops.
4. Coagulopathy often develops if the mother survives long enough, often giving rise to massive postpartum
   haemorrhage.

The underlying pathophysiological process has been compared to anaphylaxis or severe sepsis.

Diagnosis in nonfatal cases is clinical, as there is no established accurate diagnostic test premortem.

Question 3

A 34 year old woman suddenly collapses and suffers a seizure following a normal delivery of a healthy term infant.

a. List the classical clinical features that would make you suspect amniotic fluid embolus (AFE) as the cause. (5 marks)

Answer 3

• Sudden & catastrophic hypotension, hypoxia & respiratory distress
• Cardiopulmonary arrest – 87%
• Disseminated intravascular coagulopathy (DIC) – 83%
• Pulmonary oedema
• Seizures
• Fetal distress (if not delivered)

To make clinical diagnosis need all 4 of the following:

1. Acute hypotension or cardiac arrest
2. Acute hypoxia (breathlessness, cyanosis, seizures)
3. Evidence of DIC or massive haemorrhage in absence of other possible explanations
4. All occurring during labour, Caesarean section, ERPC or within 30 minutes of delivery, with no other possible explanation for findings

Question 4

. What other conditions might you consider in your differential diagnosis? (4 marks) (maternal collapse)

Answer 4

• Pulmonary embolus
• Anaphylaxis
• Local anaesthetic toxicity
• Myocardial infarction
• Sepsis
• Haemorrhage
• Eclampsia
• Simple vasovagal attack
• Ruptured abdominal viscus
• Cardiac arrhythmia
• Dissection of thoracic aorta
• Cardiomyopathy
• Cardiac arrest
• Stroke
• Subarachnoid haemorrhage
• Substance abuse-related

Question 5

Prioritise your initial management of AFE in this post partum patient. (6 marks)

Answer 5

• Call for help – obstetric, midwifery, anaesthetic, intensivists, theatre staff, blood bank, haematologists etc.
• Initial management:
A Airway – intubate
B Breathing – high-flow oxygen
C Circulation – aggressive replacement of oxygen-carrying capacity with fluids and blood products. Instigate massive transfusion protocol if one available. Need at least 2 large bore IV cannulae initially but will need central venous access & arterial line later
D Disability – check blood sugar level, temperature, lactate
E Everything else – check for other causes of exacerbators of collapse e.g. bleeding, genital tract tears etc.
• If cardiac arrest – start cardiopulmonary resuscitation as per national & hospital protocol
• Monitoring – continual monitoring of pulse, blood pressure, respiratory rate, oxygen saturations, urine output, ECG etc.
• Correct any coagulopathy – up to and including recombinant factor VII
• May need vasopressor (noradrenalin), inotropes (dobutamine) to maintain MAP >65
• May need inotropes (digoxin) to improve cardiac output due to myocardial pump failure
• Dopamine may improve renal perfusion and myocardial contractility
• Address bleeding – ecbolics (including prostaglandin F2), possibly transfer to theatre, consider laparotomy for B Lynch suture / uterine artery ligation / hysterectomy
• Transfer to ICU once more stable
• Debrief with woman, her family and the staff involved afterwards
• Carefully document events

Question 6

Incidence of AFE?

Answer 6

2/100,000 (RCOG)

Question 7

What is the morbidity / mortality of AFE?

Answer 7

20% maternal mortality rate
Significant neurological morbidity among survivors
135/1000 perinatal mortality
(RCOG)