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Postpartum Collapse

Definition

"An acute event involving the cardiorespiratory systems and/or brain, resulting in a reduced or absent conscious level, and potentially death, occurring after delivery."

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Causes

Obstetric-Specific Causes (most common)

Modified 4 H's (in postpartum context)

• Hypovolaemia - haemorrhage (overt or concealed)
• Hypoxia - AFE, PE, aspiration, airway obstruction
• Hypo/Hyperkalaemia & metabolic - magnesium toxicity (if receiving MgSO4 for eclampsia), hypoglycaemia
• Hypothermia - contributes in massive transfusion

Modified 4 T's (in postpartum context)

• Thrombosis - pulmonary embolism, amniotic fluid embolism, coronary thrombosis
• Tension pneumothorax - after central line insertion or trauma
• Tamponade - cardiac
• Toxins/Drugs - magnesium sulphate overdose, local anaesthetic systemic toxicity (LAST) from epidural, opioid overdose, oxytocin bolus causing hypotension

Cardiac Causes

• Peripartum cardiomyopathy - dilated cardiomyopathy with onset in the last month of pregnancy or within 5 months postpartum; accounts for a significant proportion of maternal cardiac deaths
• Myocardial infarction - rare, but incidence increased in pregnancy
• Arrhythmias - aortic dissection
• Undiagnosed valvular disease (e.g., severe mitral stenosis unmasked by postpartum haemodynamic shifts)

Other Causes

• Intracranial haemorrhage (subarachnoid, intracerebral)
• Anaphylaxis (to drugs, blood products, latex)
• Hypoglycaemia (especially in diabetic patients)
• Aortic dissection - rare; associated with Marfan's syndrome, bicuspid aortic valve, severe hypertension

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Management

Step 1 - Immediate Resuscitation (ABCDE)

Step 2 - Monitoring and Investigations

• Continuous cardiac monitoring, pulse oximetry, BP
• 12-lead ECG
• Urinary catheter for urine output monitoring
• ABG / VBG
• Bedside USS (FAST scan) for concealed haemorrhage, cardiac function
• Chest X-ray

Step 3 - Cause-Specific Management

Haemorrhage (PPH)

• Bimanual compression of uterus + oxytocin infusion (40 units in 500 mL NS over 4 hours)
• Ergometrine 500 mcg IV/IM (if not hypertensive)
• Carboprost (15-methyl PGF2a) 250 mcg IM every 15 min (max 8 doses)
• Tranexamic acid 1g IV stat within 3 hours of delivery
• Massive transfusion protocol: packed red cells, FFP, platelets in 1:1:1 ratio
• If unresponsive: uterine tamponade balloon, B-Lynch suture, uterine artery ligation, interventional radiology (embolisation), hysterectomy as last resort

Eclampsia

• Magnesium sulphate: 4g IV loading dose over 5-10 minutes, then 1g/hour infusion
• Control BP: labetalol or hydralazine IV to target systolic <160 mmHg
• Monitor for Mg toxicity (absent reflexes, respiratory depression) - calcium gluconate 10 mL of 10% solution as antidote

Amniotic Fluid Embolism

• Supportive: early intubation, 100% oxygen with PEEP
• High-quality CPR if in arrest
• Treat coagulopathy with blood products (TEG/ROTEM-guided if available)
• Vasopressors/inotropes for haemodynamic instability
• Consider ECMO for refractory cardiac failure
• If undelivered: emergency caesarean section to improve maternal resuscitation

Pulmonary Embolism

• Massive PE with cardiac arrest: immediate systemic thrombolysis (alteplase 50 mg IV bolus) - contraindications apply
• Anticoagulation: unfractionated heparin infusion
• Surgical embolectomy or catheter-directed thrombolysis in specialist centres

Magnesium Toxicity

• Stop MgSO4 infusion immediately
• Calcium gluconate 10 mL of 10% IV slowly as antidote
• Respiratory support as needed

Peripartum Cardiomyopathy

• Diuretics (furosemide) for pulmonary oedema
• ACE inhibitors / ARBs (avoid in breastfeeding), hydralazine + nitrates as alternatives postpartum
• Beta-blockers (carvedilol, metoprolol)
• Anticoagulation (thromboembolism risk)
• Refer to cardiology; bromocriptine has shown benefit in some studies

Septic Shock

• Blood cultures before antibiotics
• IV broad-spectrum antibiotics within 1 hour (e.g., piperacillin-tazobactam + metronidazole)
• Fluid resuscitation; vasopressors (noradrenaline) if refractory
• Source control: surgical drainage, evacuation of retained products if indicated

Step 4 - Transfer and Ongoing Care

• Transfer to ICU/HDU with appropriate monitoring
• Multidisciplinary team involvement (obstetrics, critical care, cardiology, haematology as needed)
• Document carefully - implications for future pregnancies

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Key Points

• Haemorrhage is the most common cause; always assume concealed bleeding until proven otherwise
• The "4 H's and 4 T's" framework helps systematic identification of reversible causes
• AFE and peripartum cardiomyopathy are among the most difficult diagnoses to make rapidly
• Perimortem caesarean (if applicable and baby still in utero) should be performed at the arrest site within 4-5 minutes; transport to OR significantly delays delivery and worsens CPR quality
• Maternal survivors of postpartum collapse require counselling about risks in future pregnancies

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Postpartum Collapse

1. Definition

"Maternal collapse is a rare but life-threatening event involving the cardiorespiratory systems and/or brain, resulting in reduced or absent conscious level, and potentially death, occurring during pregnancy or in the postpartum period."

• It includes the entire puerperium (up to 6 weeks postpartum)
• It excludes simple vasovagal attacks and the post-ictal state after epilepsy (most common causes of apparent "collapse" - not covered by the RCOG guideline)
• Incidence of true maternal collapse: 0.14 to 6 per 1000 births
• Outcome depends on prompt resuscitation + rapid diagnosis + targeted therapy

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2. Causes

RCOG Modified 4 H's

RCOG Modified 4 T's

Additional Obstetric-Specific Causes

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3. Investigations

Immediate Bedside Investigations (done within minutes)

Urgent Blood Tests (drawn immediately with IV access)

Radiological and Specialist Investigations

Specific Tests for AFE

• Clotted blood sample to histology: cytokeratin staining for fetal squames, mucin, or keratin
• ROTEM / TEG: point-of-care coagulation assessment to guide blood product replacement
• (Note: No reliable antemortem biomarker currently exists; AFE remains a clinical diagnosis)

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4. Management

Immediate Response - Call for Help

• Activate obstetric emergency team: obstetric consultant + anaesthetist + senior midwife + neonatologist (if applicable)
• In hospital: call 2222 - "Obstetric Emergency and Adult Cardiac Arrest"
• Assign a scribe to record all events with timestamps

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A - Airway

• Open airway (head-tilt, chin-lift / jaw thrust)
• Remove any obstruction
• High-flow oxygen: 15 L/min via non-rebreather mask
• If GCS < 8 or respiratory failure: intubate (RSI by anaesthetist; cricoid pressure)
• Note: postpartum women still have aspiration risk (full stomach, oesophageal relaxation)

B - Breathing

• Assess respiratory rate and effort
• Pulse oximetry target: SpO2 > 95%
• Assisted ventilation if inadequate breathing
• Ventilate with bag-valve-mask until intubation ready

C - Circulation

• Two large-bore IV cannulae (14G or 16G) immediately - antecubital fossa
• If no IV access: intraosseous (IO) access
• Aggressive IV fluid resuscitation: crystalloid (warmed if available); switch to blood products early
• Continuous cardiac monitoring, pulse oximetry, non-invasive BP
• Consider arterial line for continuous BP + frequent ABG sampling
• Consider central venous access for CVP monitoring and vasopressors
• Insert urinary catheter - target urine output > 0.5 mL/kg/hour
• Vasopressors (noradrenaline) if fluid-refractory hypotension

D - Disability (Neurological)

• GCS assessment; pupillary response
• Blood glucose - treat hypoglycaemia immediately: 50 mL of 50% dextrose IV
• Temperature
• If seizures: IV benzodiazepine (lorazepam 4 mg IV); treat eclampsia with MgSO4

E - Exposure

• Full examination for source of haemorrhage
• Uterine assessment: atony? inversion?
• Skin: rash (anaphylaxis), jaundice, pallor, peripheral perfusion

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Cardiac Arrest Management (postpartum)

• Standard CPR: 30:2 at 100-120 compressions/minute on a firm flat surface
• No need for left lateral tilt in purely postpartum patients (uterus no longer gravid)
• Early defibrillation for shockable rhythms (VF/pulseless VT)
• Follow ACLS/ALS algorithm
• Address reversible causes: 4 H's and 4 T's
• Perimortem caesarean section only if undelivered with viable fetus: aim delivery within 4-5 minutes of maternal arrest; perform at the arrest site (do not transport to theatre - worsens CPR quality and delays delivery)

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Cause-Specific Ongoing Management

Postpartum Haemorrhage (PPH)

• Uterotonic drugs: Oxytocin 10 IU IM or slow IV + oxytocin infusion 40 IU in 500 mL over 4h; Ergometrine 500 mcg IM/IV (if not hypertensive); Carboprost 250 mcg IM every 15 min (max 8 doses); Misoprostol 800-1000 mcg sublingual/rectal
• Tranexamic acid 1g IV within 3 hours of delivery (WOMAN Trial evidence); repeat 1g if bleeding continues after 30 min
• Bimanual uterine compression
• Massive transfusion protocol: pRBC : FFP : Platelets = 1:1:1; ROTEM/TEG-guided if available
• If medical measures fail: uterine tamponade balloon (Bakri balloon), B-Lynch compression suture, uterine/internal iliac artery ligation, interventional radiology (embolisation), peripartum hysterectomy as last resort

Eclampsia

• Magnesium sulphate: 4g IV loading over 5-10 min, then 1-2g/hour maintenance infusion
• Control BP: Labetalol 20 mg IV (repeat up to 80 mg), or Hydralazine 5 mg IV; target systolic < 160 mmHg
• Monitor for Mg toxicity: check reflexes hourly, urine output, RR; antidote = Calcium gluconate 10 mL of 10% IV over 10 minutes
• Fluid restrict: pulmonary oedema risk; target urine output 25-30 mL/hour minimum

Amniotic Fluid Embolism

• Primarily supportive
• Early intubation + mechanical ventilation with 100% O2 and PEEP
• CPR if in arrest - high-quality compressions
• Vasopressors and inotropes for haemodynamic instability (noradrenaline, dobutamine)
• Treat DIC: FFP, cryoprecipitate, platelets, pRBC in 1:1:1 ratio; ROTEM/TEG-guided; avoid recombinant factor VIIa (associated with major organ thrombosis in AFE)
• Consider ECMO for refractory cardiac failure / prolonged arrest
• Transoesophageal echocardiography to guide management once intubated
• If undelivered: emergency caesarean to improve maternal CPR

Pulmonary Embolism

• Haemodynamically unstable / cardiac arrest: Thrombolysis - Alteplase 50 mg IV bolus; CPR must continue 60-90 min after
• Haemodynamically stable: Unfractionated heparin (UFH) infusion (weight-based)
• LMWH for ongoing anticoagulation postpartum
• Surgical embolectomy or catheter-directed thrombolysis in specialist centres for failed thrombolysis

Septic Shock (Sepsis-3 criteria)

• Blood cultures x2 before antibiotics (do not delay antibiotics > 1 hour)
• IV broad-spectrum antibiotics: e.g. Piperacillin-tazobactam 4.5g IV 8-hourly + Metronidazole 500 mg IV 8-hourly; add Gentamicin if Group A Strep suspected
• 30 mL/kg IV crystalloid bolus within 3 hours
• Vasopressors (noradrenaline) if MAP < 65 despite fluid resuscitation
• Source control: evacuation of retained products, surgical drainage of abscess, wound debridement
• ICU referral

Magnesium Sulphate Toxicity

• Stop infusion immediately
• Calcium gluconate 10 mL of 10% IV (1g) slowly as antidote
• Respiratory support; intubation if respiratory arrest
• Check serum Mg levels; signs: loss of patellar reflexes (> 3.5 mmol/L), respiratory depression (> 5 mmol/L), cardiac arrest (> 7 mmol/L)

Peripartum Cardiomyopathy

• Loop diuretics (furosemide 40 mg IV) for pulmonary oedema
• ACE inhibitors (e.g. enalapril) if not breastfeeding; Hydralazine + nitrates if breastfeeding
• Beta-blockers: carvedilol or metoprolol (evidence of reverse remodelling)
• Anticoagulation (LMWH or warfarin) - high thromboembolism risk with EF < 35%
• Bromocriptine 2.5 mg twice daily for 2 weeks has shown benefit in some RCTs
• Urgent cardiology referral; IABP or LVAD for cardiogenic shock refractory to medical therapy

Anaphylaxis

• Adrenaline (epinephrine) 0.5 mg IM into outer thigh (0.5 mL of 1:1000); repeat every 5-10 min if no improvement
• High-flow oxygen, IV fluid bolus
• Chlorphenamine 10 mg IV, hydrocortisone 200 mg IV
• Adrenaline infusion if IM doses inadequate

Local Anaesthetic Systemic Toxicity (LAST)

• Stop LA injection immediately
• Call for help; Intralipid 20% 1.5 mL/kg IV bolus then infusion
• CPR if arrest; avoid vasopressin, calcium channel blockers, beta-blockers

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Ongoing Care and Transfer

• Transfer to ICU / High Dependency Unit once stabilised
• Multidisciplinary team: obstetrics, critical care, cardiology, haematology, interventional radiology
• Contemporaneous documentation of all events and timings
• Complete a Datix / clinical incident report
• Debrief the patient's family
• Counsel about future pregnancy risks - many causes of postpartum collapse carry significant recurrence risk

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Summary Table: Quick Cause-Clue-Action

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