Maternal Collapse

Question 1

What are the differentials for a maternal collapse? (14)

Answer 1

1. Vasovagal episode
2. High epidural/total spinal block
3. Local anaesthetic toxicity
4. Haemorrhage
5. Hypertensive diseases of pregnancy (eclampsia)
6. Pulmonary embolus
7. Uterine rupture
8. Amniotic fluid embolus
9. Cardiac event
10. Cerebral event
11. Anaphylaxis
12. Electrolyte derangement (hypoglycaemia, hyponatraemia)
13. Hypovolaemia
14. Hypoxaemia

Question 2

Outline an initial management plan for a maternal collapse

Answer 2

1. Call for help
2. Position into (L) lateral for uterine displacement
3. Apply high flow oxygen
4. Assess ABCs
5. Commence CPR if no output
6. If any seizure activity - needs Magnesium 1gm over 5mins or Midazolam 2mg bolus
7. Intubate if required
8. Establish IV access
9. Apply monitoring
10. Treat reversible causes
11. O&G review of fetal wellbeing

Question 3

Outline the management of an eclamptic seizure

Answer 3

1. Call for help
2. Position (L) lateral
3. Apply high flow O2, but don’t bag while seizing
4. Terminate seizure with Magnesium 1gm over 5mins, Midazolam 2mg boluses, Propofol or Thiopentone
5. Correct any hypotension, hypoxia, hypoglycaemia or electrolyte disturbances
6. Establish monitoring
7. O&G review of fetal wellbeing
8. Commence Magnesium infusion
9. Phenytoin load if no response to Magnesium
10. Treat hypertension - Nifedipine, Clonidine or Hydralazine
11. Neuro assessment once seizure terminated
12. Bloods including coags
13. Organise appropriate post-event monitoring space

Question 4

How is a magnesium infusion prepared?

Answer 4

10gm of Magnesium (20mLs 50%) diluted to 50mLs with normal saline (200mg/mL)

Commence at 5mLs/hr (1gm/hr)

Monitor knee jerk reflex, serum Mg level and ECG

Loss of reflexes, hypotension, widening QRS/AV block are signs of toxicity

Question 5

What is the treatment for Magnesium toxicity?

Answer 5

Calcium chloride

Question 6

What are the possible causes of hyponatraemia in pregnancy?

Answer 6

• Hyponatraemia of pregnancy related to Osmoreceptor re-set
• Dextrose containing solutions
• Syntocinon (analogue of Vasopressin)
• SIADH
• Pre-eclampsia

Question 7

What are the presenting signs of amniotic fluid embolism?

Answer 7

• Dysnpoea
• respiratory distress
• cardiovascular collapse
• seizures
• Occ coagulopathy

Question 8

Outline management of amniotic fluid embolism

Answer 8

No specific management

Supportive care following the management plan for maternal collapse

Question 9

What are the anaesthetic considerations for a patient with pre/eclampsia?

Answer 9

• Coagulopathy is likely - regional will be contraindicated
• Tight control of blood pressure - needs an IAL and IDC
• Continue Magnesium infusion due to risk of seizure both during and post anaesthesia
• Often significant airway oedema - anticipate a difficult intubation
• Sympathetic response to intubation will exacerbate hypertension - response needs to be blunted (Remifentanil 1mcg/kg bolus, Alfentanil 10mcg/kg bolus, Mag, Esmolol)
• NDMRs will have prolonged effect
• Suxamethonium will no produce fasciculations
• Ergometrine and NSAIDs are contraindicated
• Likely require ICU post-op