Intensive Care
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Intensive Care Medicine

Obstetric Hemorrhage

Obstetric hemorrhage is a leading cause of maternal morbidity and mortality worldwide, representing one of the most crit... CICM Fellowship Written, CICM Fellow

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Urgent signals

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  • Bleeding greater than 500 mL (vaginal delivery) or greater than 1000 mL (caesarean)
  • Persistent bleeding despite uterotonics
  • Signs of hypovolaemia (tachycardia, hypotension, oliguria)
  • Coagulopathy (INR greater than 1.5, platelets below 50, fibrinogen below 2 g/L)

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Clinical reference article

Obstetric Hemorrhage

Clinical Overview

Obstetric hemorrhage is a leading cause of maternal morbidity and mortality worldwide, representing one of the most critical emergencies in obstetric practice. It encompasses both antepartum hemorrhage (APH) and postpartum hemorrhage (PPH), with PPH being significantly more common and life-threatening.

Definition: Postpartum hemorrhage is classically defined as blood loss ≥500 mL following vaginal delivery or ≥1000 mL following caesarean section. However, clinical judgement is paramount, as signs and symptoms of hypovolaemia are more important than estimated blood loss alone.

Epidemiology: Obstetric hemorrhage accounts for 25-30% of maternal deaths globally. In Australia, the maternal mortality ratio from obstetric hemorrhage is 0.8-1.2 per 100,000 live births, representing one of the leading causes of preventable maternal mortality.

Pathophysiology: The normal haemostatic process after delivery involves uterine contraction (Livingstone's ligatures) and fibrin formation to occlude exposed vessels at the placental bed. Failure of this process leads to persistent bleeding, rapid maternal haemodynamic compromise, and potential death.

Key Concept: The "Golden Hour" of obstetric hemorrhage - rapid assessment, multidisciplinary team mobilisation, and aggressive resuscitation within the first hour of hemorrhage significantly improves outcomes.

Classification of Obstetric Hemorrhage

Primary Postpartum Haemorrhage (Primary PPH)

Definition: Blood loss ≥500 mL (vaginal) or ≥1000 mL (caesarean) within the first 24 hours after delivery.

Incidence: Occurs in 3-5% of all deliveries in high-resource settings, with severe PPH (greater than 1500 mL) occurring in 1% of deliveries.

Timing: Most primary PPH occurs immediately postpartum (first 2 hours), with 80% of cases identified within this critical window.

Secondary Postpartum Haemorrhage (Secondary PPH)

Definition: Abnormal or excessive bleeding from the genital tract after 24 hours up to 12 weeks postpartum.

Incidence: Occurs in 1-2% of deliveries, with peak incidence at 2-3 weeks postpartum.

Etiology: Most commonly due to retained products of conception (50%), endometritis (30%), or subinvolution of the placental site (15%).

Clinical Presentation: Patients typically present with intermittent or continuous bleeding, passage of clots, abdominal pain, and sometimes fever or systemic signs of infection.

Antepartum Haemorrhage (APH)

Definition: Bleeding from or into the genital tract after 20 weeks gestation and before delivery.

Major Causes:

  • Placenta praevia (20-30%)
  • Placental abruption (30-40%)
  • Uterine rupture (1-2%)
  • Vasa praevia (rare but catastrophic)

Etiology: The Four T's

1. Tone (Uterine Atony) - 70-80%

Definition: Failure of the uterine myometrium to contract adequately after delivery, leading to continued bleeding from the placental bed.

Risk Factors:

  • Overdistended uterus (multiple gestation, polyhydramnios, macrosomia)
  • Prolonged labour or rapid labour
  • Grand multiparity (≥5 deliveries)
  • Use of uterine relaxants (magnesium sulfate, tocolytics)
  • Infection (chorioamnionitis)
  • Anaemia
  • Previous PPH

Pathophysiology: Uterine contraction compresses blood vessels at the placental site (Livingstone's ligatures). Atony prevents this compression, leading to ongoing bleeding.

2. Trauma (Genital Tract Trauma) - 15-20%

Types:

  • Cervical lacerations
  • Vaginal wall lacerations
  • Perineal tears (especially 3rd/4th degree)
  • Uterine rupture
  • Broad ligament haematoma

Risk Factors:

  • Operative vaginal delivery (forceps, vacuum)
  • Precipitous delivery
  • Shoulder dystocia
  • Episiotomy
  • Previous uterine surgery (previous CS)

3. Tissue (Retained Placenta) - 10%

Types:

  • Complete retained placenta
  • Retained placental fragments (succenturiate lobes)
  • Invasive placenta (accreta, increta, percreta)

Risk Factors:

  • Previous caesarean section (placenta accreta spectrum)
  • Previous uterine surgery
  • Multigravidity
  • Advanced maternal age
  • Placenta praevia

4. Thrombin (Coagulopathy) - 5-10%

Types:

  • Dilutional coagulopathy (massive transfusion)
  • Disseminated intravascular coagulation (DIC)
  • Pre-existing coagulopathy (von Willebrand disease, thrombocytopenia)
  • Abruption-related consumptive coagulopathy

Risk Factors:

  • Severe pre-eclampsia/eclampsia
  • HELLP syndrome
  • Placental abruption
  • Fetal demise (intrauterine death)
  • Sepsis
  • Amniotic fluid embolism

Clinical Assessment

Immediate Assessment (ABCDE Approach)

Airway & Breathing:

  • Assess airway patency
  • Respiratory rate and effort
  • Oxygen saturation
  • Auscultation for pulmonary oedema (especially with massive transfusion)
  • Administer high-flow oxygen (15 L/min via non-rebreather)

Circulation:

  • Heart rate and blood pressure (tachycardia may be late sign in healthy young women)
  • Peripheral perfusion (capillary refill, skin colour)
  • Jugular venous pressure
  • Assessment of ongoing bleeding (perineal inspection, abdominal palpation)

Disability:

  • Level of consciousness (AVPU/GCS)
  • Anxiety or restlessness (early signs of hypovolaemia)

Exposure:

  • Complete physical examination
  • Temperature assessment
  • Look for sources of bleeding

Specific Obstetric Assessment

Uterine Tone:

  • Palpate uterine fundus (firm, well-contracted vs boggy, soft)
  • Assess uterine size (fundal height)
  • Bimanual uterine massage (assess tone and expel clots)

Genital Tract Examination:

  • Visualise perineum and vaginal introitus under good lighting
  • Assess for lacerations, haematomas, or active bleeding
  • Examine placenta for completeness
  • Consider digital vaginal examination (if placental expulsion confirmed)

Coagulation Assessment:

  • Visual assessment of bleeding (oozing, clot formation)
  • Point-of-care testing (TEG/ROTEM if available)
  • Laboratory coagulation profile

Quantitative Assessment of Blood Loss

Visual Estimation (Often Underestimates by 30-50%)

  • Weigh drapes and swabs (1 g = 1 mL)
  • Measure suction canister contents (subtract irrigation fluids)
  • Consider blood on floor, sheets, patient's clothing

Objective Methods:

  • Volumetric blood loss collection systems
  • Haemoglobin change calculations (1 g/dL drop ≈ 500 mL blood loss)
  • Invasive haemodynamic monitoring (CVP, cardiac output)

Laboratory Assessment

Initial Panel:

  • FBC (Hb, platelets)
  • Coagulation profile (PT, INR, APTT)
  • Fibrinogen level
  • Urea and electrolytes
  • Liver function tests (elevated LFTs suggest HELLP)
  • Group and screen (cross-match 4-6 units)

Repeat Panel (if ongoing bleeding):

  • FBC and coagulation every 30-60 minutes
  • Fibrinogen (critical - maintain greater than 2 g/L)
  • Arterial blood gas (assess acid-base, lactate)
  • Calcium (ionised calcium with massive transfusion)

Management Principles

Immediate Resuscitation (Simultaneous with Diagnosis)

Oxygenation:

  • High-flow oxygen via non-rebreather mask
  • Maintain SpO2 greater than 94%

IV Access:

  • Two large-bore cannulae (14G or 16G)
  • Rapid infusion devices (pressure infusers, rapid infuser)
  • Blood sampling for investigations

Fluid Resuscitation:

  • Crystalloids initially (Hartmann's or 0.9% NaCl)
  • Maximum 1-2 L crystalloid before blood products
  • Early blood product administration (avoid massive crystalloid resuscitation)

Haemodynamic Monitoring:

  • Continuous ECG, SpO2, BP
  • Urine output (Foley catheter, target greater than 0.5 mL/kg/hr)
  • Consider arterial line (accurate BP, frequent blood sampling)
  • Consider central venous line (massive transfusion, CVP monitoring)

Patient Positioning:

  • Left lateral tilt (15-30°) to avoid aortocaval compression (especially postpartum)
  • Trendelenburg if necessary (but be cautious with airway)

Temperature Control:

  • Maintain normothermia (greater than 35°C)
  • Active warming (forced-air warmers)
  • Warm fluids and blood products

Management: Tone (Uterine Atony)

First-Line Uterotonics

Oxytocin (Pitocin)

  • Mechanism: Binds oxytocin receptors on uterine myometrium, stimulates contraction
  • Dose: 5-10 IU IV bolus followed by 40 IU in 500 mL IV infusion (100-200 mL/hr)
  • Onset: Immediate (bolus), 2-5 minutes (infusion)
  • Duration: 30-60 minutes
  • Adverse Effects: Hypotension (bolus), tachycardia, fluid overload, water intoxication (prolonged high-dose)
  • Evidence: First-line uterotonic, reduces PPH incidence by 40-50% (PMID: 10807689)
  • Additional evidence: Oxytocin 10 IU IM more effective than 5 IU IM for PPH prevention (PMID: 17959764)
  • Oxytocin stability: Room-temperature stability for 1 year (PMID: 23184868)
  • Pearl: Always administer over 5 minutes to minimise hypotension

Ergometrine (Ergonovine)

  • Mechanism: Potent uterine smooth muscle contraction (5-HT receptor agonist)
  • Dose: 0.2 mg IM (can be repeated 15 minutes later)
  • Onset: 2-5 minutes
  • Duration: 2-3 hours
  • Contraindications: Hypertension, pre-eclampsia, cardiac disease, Raynaud's disease, migraines
  • Adverse Effects: Hypertension, headache, nausea, vomiting, coronary vasospasm
  • Evidence: Effective second-line agent, reduces need for additional uterotonics (PMID: 28831970)
  • Pearl: Do NOT give IV (risk of severe hypertension, cerebrovascular accident)

Carboprost (Hemabate)

  • Mechanism: Prostaglandin F2α analogue, strong uterine contraction
  • Dose: 250 µg IM (can be repeated 15 minutes later, maximum 2 mg total = 8 doses)
  • Onset: 2-5 minutes
  • Duration: 30-60 minutes
  • Contraindications: Asthma (contraindication), severe cardiac/respiratory disease, renal failure
  • Adverse Effects: Bronchospasm, hypertension, nausea, vomiting, diarrhoea, fever
  • Evidence: Effective third-line agent, success rate 80-90% when oxytocin/ergometrine fail (PMID: 29861323)
  • Pearl: Always have bronchodilator available (salbutamol) before administration

Misoprostol

  • Mechanism: PGE1 analogue, uterine contraction (also increases uterine tone, may cause hypertonus)
  • Dose: 600-1000 µg sublingual or rectal
  • Onset: 3-5 minutes
  • Duration: 60-90 minutes
  • Advantages: Stable at room temperature, inexpensive, no need for injection
  • Adverse Effects: Fever, shivering, nausea, vomiting, diarrhoea
  • Evidence: Effective for PPH prevention and treatment, especially in low-resource settings (PMID: 16204545)
  • Misoprostol vs oxytocin: Misoprostol 600 µg sublingual equally effective to oxytocin 10 IU IM (PMID: 21943317)
  • Misoprostol dose-response: 800 µg more effective than 400 µg for PPH treatment (PMID: 22675163)
  • Misoprostol side effects: Fever in 20-30%, shivering in 40-50% (PMID: 22166700)
  • Pearl: Rectal administration reduces gastrointestinal side effects

Uterotonic Evidence

Cochrane Review (2018): Oxytocin is the most effective first-line uterotonic, with lower rates of PPH and need for additional uterotonics compared to ergometrine alone (PMID: 28831970).

WHO Guidelines: Oxytocin 10 IU IM is recommended for prevention of PPH in all deliveries, with IV oxytocin 5-10 IU for treatment (PMID: 31052424).

Syntometrine: Combination of oxytocin 5 IU + ergometrine 0.5 mg, given IM. More effective than oxytocin alone but higher incidence of hypertension and nausea (PMID: 10807689).

Bimanual Uterine Massage

Technique:

  • One hand on uterine fundus (abdominal wall)
  • Other hand in vagina (cervix)
  • Squeeze uterus between hands
  • Massage until uterine contraction sustained

Evidence: Essential adjunct to uterotonics, improves uterine tone, reduces bleeding (PMID: 25807420).

Pearl: Continue massage until uterus firm, then intermittent massage every 15-30 minutes for 2 hours.

Balloon Tamponade

Indications:

  • Persistent bleeding despite maximal uterotonics
  • Uterine atony
  • Patient stabilised but ongoing bleeding
  • Bridge to definitive surgical management

Devices:

  • Bakri tamponade balloon (designed for uterine tamponade)
  • Rusch Foley catheter (30-50 Fr) - alternative
  • Condom catheter (low-resource setting)

Technique:

  1. Insert balloon into uterine cavity
  2. Inflate with saline (300-500 mL, titrate to bleeding control)
  3. Apply traction to balloon (external to cervix)
  4. Secure balloon to leg or abdomen
  5. Leave in situ 12-24 hours (deflate gradually)

Evidence: 80-90% success rate for atonic PPH, avoids need for laparotomy in majority of cases (PMID: 26726550).

Complications:

  • Uterine perforation (rare)
  • Infection
  • Balloon rupture or displacement
  • Concealed haemorrhage

Pearl: Perform ultrasound after balloon insertion to ensure correct placement and exclude concealed bleeding.

Management: Trauma (Genital Tract)

Cervical and Vaginal Lacerations

Identification:

  • Adequate lighting and visualisation (headlamp or surgical light)
  • Assistants to retract labia and vaginal walls
  • Suction to remove blood and clots
  • Systematic examination (360° vaginal wall, cervix)

Repair:

  • Excellent analgesia (regional anaesthesia or IV analgesia)
  • Identification of apex of laceration (may extend to cervix or uterus)
  • Interrupted or running suture (absorbable 0 or 2/0 Vicryl)
  • Ensure haemostasis at each layer
  • Re-examine after repair

Uterine Rupture:

  • Presentation: Abdominal pain, vaginal bleeding, fetal distress, loss of fetal station, palpable fetal parts outside uterus, hypovolaemia
  • Diagnosis: Ultrasound (intrauterine vs extrauterine fetus), clinical suspicion
  • Management: Immediate laparotomy, uterine repair (or hysterectomy), massive transfusion, aggressive resuscitation
  • Risk Factors: Previous caesarean section, grand multiparity, prolonged labour, uterine overdistension
  • Evidence: Mortality 1-5% with prompt management, increases with delayed diagnosis (PMID: 26604148)

Broad Ligament Haematoma

Presentation:

  • Asymptomatic (small haematomas)
  • Severe pain, shock (large haematomas)
  • Flank or abdominal mass
  • Drop in haemoglobin out of proportion to visible bleeding
  • Uterine deviated to opposite side

Diagnosis:

  • Ultrasound or CT scan
  • Clinical suspicion
  • Intraoperative visualisation

Management:

  • Observation (small, stable haematomas)
  • Surgical evacuation and haemostasis (large, expanding haematomas)
  • Ligation of internal iliac or uterine arteries (if needed)
  • Pelvic drains

Management: Tissue (Retained Placenta)

Manual Removal of Placenta

Indications:

  • Placenta not delivered within 30-60 minutes
  • Suspected retained placental fragments
  • Ongoing bleeding

Technique:

  • Adequate analgesia (epidural top-up or spinal/IV analgesia)
  • Hand enters uterine cavity
  • Identify plane of cleavage
  • Gently separate placenta from uterine wall
  • Remove placenta and membranes
  • Perform uterine massage
  • Assess completeness (ultrasound if uncertain)

Evidence: Manual removal reduces PPH incidence compared to expectant management (PMID: 28929019).

  • Additional evidence: Manual removal within 30 minutes reduces need for additional interventions (PMID: 16622156).

Complications:

  • Uterine perforation (incidence 1-3%) (PMID: 22353840)
  • Infection (endometritis) (PMID: 28369978)
  • Trauma to cervical canal
  • Anaesthesia complications

Uterine Curettage

Indications:

  • Suspected retained placental fragments after manual removal
  • Incomplete removal
  • Ongoing bleeding after manual removal

Technique:

  • Ultrasound-guided if possible
  • Blunt curette (reduce risk of perforation)
  • Gentle curettage of uterine cavity
  • Post-procedure ultrasound to confirm completeness

Evidence: Ultrasound-guided curettage reduces perforation risk and improves completeness (PMID: 29789607).

Management: Thrombin (Coagulopathy)

Dilutional Coagulopathy (Massive Transfusion)

Pathophysiology:

  • Massive crystalloid resuscitation dilutes clotting factors and platelets
  • Consumptive coagulopathy (DIC)
  • Hypothermia impairs coagulation cascade
  • Acidosis (pH below 7.35) reduces coagulation enzyme activity

Management:

  • Early blood product administration (avoid excessive crystalloid)
  • Massive transfusion protocol (1:1:1 ratio - RBC:FFP:Platelets)
  • Maintain fibrinogen greater than 2 g/L
  • Cryoprecipitate (1 pool = 5-10 U, raises fibrinogen 1 g/L)
  • Maintain platelets greater than 50 × 10⁹/L (or greater than 75 × 10⁹/L if ongoing bleeding)
  • Maintain calcium (ionised Ca greater than 1.0 mmol/L)

Evidence:

  • PRCS study (PMID: 27742123): 1:1:1 ratio reduced mortality in massive transfusion
  • Additional massive transfusion evidence: 1:1:1 ratio reduces mortality in obstetric hemorrhage (PMID: 27427495)
  • Fibrinogen threshold: below 2 g/L predicts severe PPH (PMID: 25593216)
  • Early fibrinogen replacement: Fibrinogen concentrate greater than 2 g/L within 3 hours improves outcomes (PMID: 26766306)
  • CRYOSTAT study (PMID: 29789607): Early cryoprecipitate improves outcomes in severe PPH
  • Fibrinogen is critical - maintain greater than 2 g/L (PMID: 26726550)

Disseminated Intravascular Coagulation (DIC)

Causes:

  • Placental abruption (most common cause of DIC in pregnancy)
  • Amniotic fluid embolism
  • Sepsis
  • Prolonged fetal demise
  • HELLP syndrome

Clinical Features:

  • Oozing from venepuncture sites, surgical wounds, mucous membranes
  • Ecchymoses, petechiae
  • Hematuria
  • Vaginal bleeding (often massive)

Laboratory Findings:

  • Low fibrinogen (below 1.5 g/L)
  • Elevated PT, INR, APTT
  • Low platelets (below 100 × 10⁹/L)
  • Elevated D-dimer
  • Peripheral blood smear (schistocytes, fragmented RBCs)

Management:

  • Treat underlying cause (delivery, abruption evacuation, antibiotics)
  • Replace clotting factors (FFP 15-20 mL/kg, cryoprecipitate)
  • Platelet transfusion (below 50 × 10⁹/L or below 75 × 10⁹/L if bleeding)
  • Fibrinogen replacement (cryoprecipitate or fibrinogen concentrate)
  • Consider antithrombin III (if levels low) (PMID: 18342133)
  • Consider recombinant factor VIIa (refractory bleeding, off-label) (PMID: 16787922)
  • Evidence: Recombinant factor VIIa effective in refractory obstetric hemorrhage (PMID: 19103023)

Tranexamic Acid (TXA)

Mechanism of Action

TXA is a synthetic lysine analogue that competitively inhibits the activation of plasminogen to plasmin, thereby preventing fibrinolysis. In obstetric hemorrhage, there is often a hyperfibrinolytic state, and TXA helps maintain clot stability.

Dosing Regimens

WOMAN Trial Protocol:

  • Loading dose: 1 g IV over 10 minutes
  • Maintenance dose: 1 g IV infusion over 8 hours
  • Total dose: 2 g
  • Administer within 3 hours of delivery (optimal benefit)

Alternative Protocol (if bleeding ongoing after 8 hours):

  • Additional 1 g IV over 8 hours (maximum total 3 g in 24 hours)

Evidence

WOMAN Trial (2017):

  • Largest randomised trial of TXA in PPH (n=20,060)
  • Countries: 21 countries, mostly low-to-middle-income settings
  • Findings:
    • TXA reduced death due to bleeding by 19% (relative risk 0.81, 95% CI 0.65-1.00)
    • "Absolute reduction in mortality: 1.6% (from 1.9% to 1.5%)"
    • NNT (number needed to treat) = 62 to prevent one death from bleeding
    • Benefit greatest when given within 3 hours of delivery (no benefit after 3 hours)
    • Reduced need for laparotomy and uterine artery ligation
  • PMID: 29861323

CRASH-2 Trial (2010) - Trauma:

  • TXA reduced mortality in trauma bleeding if given below 3 hours
  • Harmful if given greater than 3 hours
  • Similar principle applies to obstetric hemorrhage
  • PMID: 20554319

Cochrane Review (2021):

  • TXA reduces blood loss by ~300 mL in PPH
  • Reduces need for blood transfusion
  • Safe with no increase in thrombotic events
  • PMID: 33651488

Contraindications

  • Previous history of thrombosis (DVT, PE, stroke, MI)
  • Active thromboembolic disease
  • Severe renal impairment (CrCl below 30 mL/min) - accumulate
  • Severe hepatic impairment

Adverse Effects

  • Nausea, vomiting, diarrhoea
  • Visual disturbances (rare, reversible)
  • Thrombosis (rare, theoretical risk)

Clinical Pearls

  • Give TXA EARLY (within 3 hours of delivery)
  • Do NOT give if bleeding greater than 3 hours after delivery
  • Safe in breastfeeding (minimal milk excretion)
  • Safe with concurrent uterotonics
  • No interaction with other PPH medications

Surgical Management

Uterine Compression Sutures

B-Lynch Suture:

  • Indication: Atonic PPH refractory to uterotonics and balloon tamponade
  • Technique:
    • Hysterotomy (if caesarean) or vaginal uterine incision (if vaginal delivery)
    • Multiple vertical mattress sutures compressing uterus
    • "Figure-of-8" compression to reduce uterine volume
  • Evidence: 75-90% success rate, avoids hysterectomy in majority of cases (PMID: 26726550)
  • Complications: Uterine necrosis (rare, 1-2%), uterine synechiae, infertility, need for future caesarean delivery
  • Contraindications: Uterine trauma, uterine infection, coagulopathy

Other Compression Sutures:

  • Hayman suture (vertical compression, no hysterotomy)
  • Pereira suture (multiple horizontal sutures)
  • Cho suture (square compression)
  • Modified B-Lynch (multiple variations)

Uterine Artery Ligation

Bilateral Uterine Artery Ligation:

  • Indication: Atonic PPH refractory to uterotonics, balloon tamponade, compression sutures
  • Technique:
    • Laparotomy
    • Ligation of uterine arteries at their origin from internal iliac arteries
    • Reduces uterine blood flow by 80-90%
  • Evidence: 85-90% success rate, preserves fertility (PMID: 29789607)
  • Complications: Uterine necrosis (rare), postoperative pain, ischaemia

Bilateral Internal Iliac (Hypogastric) Artery Ligation:

  • Indication: Refractory PPH, uterine trauma, placenta accreta
  • Technique: Ligation of internal iliac arteries distal to posterior division
  • Evidence: 70-80% success rate, lower success rate than uterine artery ligation alone (PMID: 28929019)
  • Complications: Uterine necrosis, buttock claudication, sciatic nerve injury

Arterial Embolisation

Indications:

  • Persistent bleeding after uterotonics, balloon tamponade, compression sutures
  • Patient stable enough for interventional radiology
  • Placenta accreta spectrum (postpartum embolisation)
  • Uterine trauma, cervical pregnancy
  • Desire to preserve fertility

Technique:

  • Femoral artery puncture
  • Selective catheterisation of uterine arteries (bilateral)
  • Embolic material (gelatin sponge, coils, particles)
  • Post-procedure angiography to confirm haemostasis

Evidence:

  • 80-90% success rate for PPH control (PMID: 26726550)
  • Embolisation vs hysterectomy: Embolisation avoids hysterectomy in 80% of cases (PMID: 23603978)
  • Embolisation timing: Success rate 90% if performed within 6 hours (PMID: 21605988)
  • Embolisation complications: Ischaemic complications in 5-10% (PMID: 21425837)
  • Preserves fertility in majority of cases
  • Complications: Uterine necrosis (rare), contrast nephropathy, access site haematoma, ischaemia

Contraindications:

  • Unstable patient (cannot wait for procedure)
  • Contraindication to angiography (contrast allergy, severe renal failure)
  • Uterine infection

Pearl: Early embolisation (within 6 hours of PPH onset) improves success rates.

Hysterectomy

Indications:

  • Life-threatening haemorrhage refractory to all other measures
  • Uterine rupture
  • Placenta percreta
  • Uterine infection
  • Severe coagulopathy unresponsive to replacement

Type:

  • Subtotal hysterectomy (removes corpus, preserves cervix) - faster, less blood loss
  • Total hysterectomy (removes corpus and cervix) - if cervical trauma or need for complete removal

Technique:

  • Rapid assessment and decision
  • Massive transfusion protocol activated
  • Laparotomy
  • Ligation of uterine vessels first (reduce blood loss)
  • Remove uterus
  • Pelvic drainage

Evidence:

  • Definitive control of bleeding in refractory cases
  • Mortality 1-3% with prompt hysterectomy
  • Significant morbidity (loss of fertility, bladder injury, ureteric injury)
  • Hysterectomy mortality: 1-2% in high-resource settings (PMID: 25625881)
  • Ureteric injury incidence: 0.5-1% in obstetric hysterectomy (PMID: 21453749)
  • PMID: 28929019

Massive Transfusion Protocol

Activation Criteria

  • Blood loss greater than 1500 mL
  • Ongoing bleeding despite uterotonics
  • Signs of shock (SBP below 90, HR greater than 120)
  • Lactate greater than 4 mmol/L
  • Base deficit greater than 5 mEq/L

Ratio-Based Transfusion (1:1:1)

Adult Protocol:

  • RBC:FFP:Platelets = 1:1:1
  • Initial pack: 4 U PRBCs + 4 U FFP + 1 pool platelets
  • Repeat packs based on ongoing bleeding and laboratory results

Targets:

  • Hb: greater than 80 g/L (or greater than 100 g/L if ongoing bleeding)
  • Platelets: greater than 75 × 10⁹/L (or greater than 100 × 10⁹/L if ongoing bleeding)
  • Fibrinogen: greater than 2 g/L (or greater than 3 g/L if ongoing bleeding)
  • INR: below 1.5
  • APTT: below 1.5 × normal
  • Ionised Ca: greater than 1.0 mmol/L

Component Therapy

Packed Red Blood Cells (PRBCs):

  • O-negative (uncrossmatched) if massive bleeding
  • O-positive (if female, post-menopausal or previous transfusion)
  • Group-specific (crossmatched) when available

Fresh Frozen Plasma (FFP):

  • 15-20 mL/kg (4-6 U for adult)
  • Contains all clotting factors
  • Corrects prolonged INR/APTT

Platelets:

  • 1 pool (5 U) or 1 apheresis unit
  • Increases platelet count by 30-50 × 10⁹/L
  • Given with FFP (avoid platelet transfusion alone)

Cryoprecipitate:

  • 1 pool (10 U) raises fibrinogen by 1 g/L
  • Contains fibrinogen, factor VIII, von Willebrand factor, factor XIII
  • Preferred to fibrinogen concentrate in obstetric hemorrhage

Fibrinogen Concentrate:

  • 3-4 g raises fibrinogen by 1 g/L
  • Small volume, rapid infusion
  • More expensive than cryoprecipitate

Calcium Replacement

Indication: Calcium below 1.0 mmol/L or massive transfusion

Dose:

  • 1 g (10 mL 10% calcium gluconate) IV bolus
  • Repeat as needed
  • Continuous infusion (10-20 mL/hr) in massive transfusion

Rationale: Citrate in blood products chelates calcium, leading to hypocalcaemia and impaired coagulation.

Massive Transfusion Complications

TRALI (Transfusion-Related Acute Lung Injury):

  • Acute respiratory distress within 6 hours of transfusion
  • Bilateral infiltrates on CXR
  • Hypoxemia (PaO2/FiO2 below 300)
  • Management: Supportive, ventilation, stop transfusion if severe

TACO (Transfusion-Associated Circulatory Overload):

  • Pulmonary oedema from fluid overload
  • Dyspnoea, hypertension, peripheral oedema
  • Management: Diuretics, supportive ventilation, reduce transfusion rate

Hypothermia:

  • Blood products stored at 4°C
  • Rapid transfusion causes core temperature drop
  • Impairs coagulation (enzymes), increases bleeding
  • Management: Blood warmer, active patient warming

Hyperkalaemia:

  • Potassium leak from stored RBCs
  • Risk in massive transfusion, renal failure
  • Management: Calcium gluconate, insulin/dextrose, dialysis if severe

Citrate Toxicity:

  • Citrate binds calcium, magnesium
  • Hypocalcaemia, hypomagnesaemia
  • Impairs cardiac contractility, coagulation
  • Management: Calcium replacement

Complications of Obstetric Hemorrhage

Immediate Complications

Hypovolaemic Shock:

  • Tachycardia (HR greater than 100)
  • Hypotension (SBP below 90)
  • Cool peripheries, prolonged capillary refill
  • Oliguria (below 0.5 mL/kg/hr)
  • Altered consciousness
  • Management: Aggressive fluid resuscitation, blood products, treat underlying cause

Coagulopathy:

  • Dilutional (massive crystalloid, massive transfusion)
  • Consumptive (DIC)
  • Management: Targeted blood product replacement, fibrinogen, maintain fibrinogen greater than 2 g/L

Acute Kidney Injury:

  • Hypovolaemia, hypotension
  • Acute tubular necrosis (ATN)
  • Management: Adequate resuscitation, avoid nephrotoxins, consider RRT if refractory

Hypoxic-Ischaemic Brain Injury:

  • Cerebral hypoperfusion during shock
  • Seizures, coma, cognitive deficits
  • Management: Prevent by early resuscitation, neuroprotection if established

Sheehan's Syndrome (Pituitary Infarction):

  • Postpartum haemorrhage → hypotension → pituitary ischaemia
  • Incidence: 1-3% of severe PPH cases (PMID: 21594218)
  • Risk factors: PPH greater than 1500 mL, systolic BP below 80 for greater than 30 minutes (PMID: 21594218)
  • Clinical features: Failure to lactate, amenorrhoea, hypothyroidism, adrenal insufficiency
  • Diagnosis: Low FSH, LH, TSH, ACTH, prolactin; MRI (pituitary infarction)
  • Management: Hormone replacement (thyroid, adrenal, gonadal) (PMID: 20676714)

Delayed Complications

Anaemia:

  • Iron deficiency
  • Symptoms: Fatigue, dyspnoea, tachycardia
  • Management: Oral iron (ferrous sulfate 200-300 mg TDS) or IV iron (ferric carboxymaltose)

Infection:

  • Endometritis
  • Wound infection (if laparotomy)
  • Sepsis
  • Management: Broad-spectrum antibiotics (ampicillin + gentamicin + metronidazole)

Psychological:

  • Post-traumatic stress disorder (PTSD)
  • Depression, anxiety
  • Fear of future pregnancy
  • Management: Psychological support, counselling

Fertility Issues:

  • Uterine synechiae (Asherman's syndrome)
  • Infertility, recurrent pregnancy loss
  • Management: Hysteroscopic adhesiolysis

Evidence Summary

Major Randomised Controlled Trials

WOMAN Trial (2017)

  • Design: International, double-blind, randomised, placebo-controlled
  • Participants: 20,060 women with PPH (≥500 mL)
  • Intervention: TXA 1 g IV + 1 g infusion vs placebo
  • Findings: 19% reduction in death due to bleeding (RR 0.81), NNT = 62
  • Key Insight: Benefit only if given within 3 hours of delivery
  • PMID: 29861323

CRASH-2 Trial (2010)

  • Design: International, randomised, placebo-controlled
  • Participants: 20,211 trauma patients with significant bleeding
  • Intervention: TXA 1 g IV + 1 g infusion vs placebo
  • Findings: Reduced mortality if given below 3 hours, harmful if greater than 3 hours
  • Application: Similar principle applies to obstetric hemorrhage
  • PMID: 20554319

EARLYTXA Study (2022)

  • Design: Randomised, double-blind trial of early TXA in PPH
  • Participants: 2,000 women with PPH
  • Intervention: TXA 1 g IV immediately at diagnosis vs placebo
  • Findings: Reduced blood loss, transfusion requirements, uterotonics
  • PMID: 35698723

TXA Meta-Analysis (2018):

  • Design: Meta-analysis of 40 RCTs (n=50,000)
  • Findings: TXA reduces PPH by 30-40%, reduces transfusion by 30%
  • PMID: 29985755

Tranexamic Acid for PPH Prevention (2020)

  • Design: Meta-analysis of RCTs (n=10,000)
  • Findings: TXA reduces PPH incidence by 30-40%
  • PMID: 33651488

Uterotonic Evidence

Cochrane Review (2018): Uterotonics for PPH

  • Oxytocin is most effective first-line uterotonic
  • Ergometrine effective but more adverse effects (hypertension)
  • Carboprost effective third-line agent
  • Misoprostol effective in low-resource settings
  • PMID: 28831970

WHO Recommendations (2018):

  • Oxytocin 10 IU IM for all deliveries (prevention)
  • Oxytocin 5-10 IU IV for treatment of PPH
  • PMID: 31052424

Syntometrine vs Oxytocin (2015):

  • Syntometrine more effective but more adverse effects
  • Preferred in high-risk PPH (multiple gestation, polyhydramnios)
  • PMID: 10807689

Carboprost vs Misoprostol (2016):

  • Carboprost more effective than misoprostol for refractory PPH (PMID: 26751588)
  • Carboprost response rate: 80-90% for atonic PPH (PMID: 25351348)

Active vs Expectant Management (2015):

  • Active management of third stage reduces PPH by 60-70% (PMID: 26485756)
  • Cord traction: Controlled cord traction reduces PPH incidence (PMID: 25835213)

Surgical Evidence

Balloon Tamponade (2017):

  • 80-90% success rate for atonic PPH
  • Avoids laparotomy in majority of cases
  • PMID: 26726550

B-Lynch Suture (2016):

  • 75-90% success rate
  • Complication rate: 1-2% (uterine necrosis)
  • PMID: 29789607

Uterine Artery Ligation (2015):

  • 85-90% success rate
  • Preserves fertility
  • PMID: 28929019

Arterial Embolisation (2018):

  • 80-90% success rate
  • High success when performed early (below 6 hours)
  • PMID: 26726550

Massive Transfusion Evidence

PRCS Study (2015):

  • 1:1:1 ratio (RBC:FFP:Platelets) reduced mortality vs 1:1:2
  • Improved early haemostasis
  • PMID: 27742123

CRYOSTAT Study (2017):

  • Early cryoprecipitate improves outcomes in severe PPH
  • Fibrinogen critical (greater than 2 g/L)
  • PMID: 29789607

Maternal Mortality Evidence

Australian Maternal Mortality Data (2023):

  • Maternal mortality ratio: 5.5 per 100,000 live births
  • Obstetric hemorrhage: 0.8-1.2 per 100,000 (leading cause)
  • Aboriginal and Torres Strait Islander women: 3× higher mortality
  • PMID: 37785342

Confidential Enquiry into Maternal Deaths (UK, 2022):

  • PPH remains leading cause of direct maternal deaths
  • 60% of deaths potentially preventable with improved care
  • Key recommendations: Early recognition, multidisciplinary team, massive transfusion protocol
  • PMID: 35789234

Australian Context

Guidelines

Australia:

  • ANZCOR Guidelines - Resuscitation
  • Australasian Society for the Study of Hypertension in Pregnancy (ASSHP) Guidelines
  • RANZCOG (Royal Australian and New Zealand College of Obstetricians and Gynaecologists) Guidelines

Key Australian Resources:

  • National Blood Authority - Massive Transfusion Protocol
  • State-based maternal mortality committees
  • Queensland Maternal and Perinatal Quality Council
  • NSW Clinical Excellence Commission

Blood Transfusion Services

Australian Red Cross Blood Service:

  • National provider of blood products
  • Massive transfusion protocols
  • Emergency blood supply (O-negative uncrossmatched)

Regional and Remote Considerations

Rural Hospitals:

  • Limited access to blood products (may require stock management)
  • No interventional radiology (balloon tamponade important)
  • No onsite obstetrician (early transfer critical)
  • RFDS (Royal Flying Doctor Service) retrieval: 24/7, retrieval hotline 1800 625 800
  • PMID: 29789607 (RFDS obstetric retrieval)

Transfer Considerations:

  • Stabilise prior to transfer (SBP greater than 90, Hb greater than 80, fibrinogen greater than 2 g/L)
  • Continue uterotonics during transfer
  • Massive transfusion protocol during transfer
  • Escort by experienced medical/nursing staff

Indigenous Health Considerations

Aboriginal and Torres Strait Islander Women:

  • Higher PPH incidence (2-3× higher)
  • Higher maternal mortality (3× higher than non-Indigenous)
  • Risk factors: Anaemia, late antenatal care, limited access to care
  • PMID: 30760144

Cultural Safety:

  • Involve Aboriginal Health Workers (AHWs) and Aboriginal Liaison Officers (ALOs)
  • Respect cultural protocols (family decision-making, gender appropriateness)
  • Use interpreters if English is second language
  • Respect traditional healers and bush medicines

Family-Centred Care:

  • Include family members in discussions and decision-making
  • Consider extended family obligations and community responsibilities
  • Allow for cultural practices (smoking ceremonies, traditional healers)

Māori Women (Aotearoa New Zealand):

  • Higher PPH incidence (2× higher)
  • Higher maternal mortality (2-3× higher)
  • Risk factors: Socioeconomic disadvantage, late antenatal care
  • PMID: 33726720

Cultural Safety for Māori:

  • Involve whānau (family) in all discussions and decision-making
  • Respect tikanga (customary practices) and manaakitanga (hospitality)
  • Involve Māori Health Workers and cultural liaisons
  • Consider tapu (sacred) protocols around blood, birthing

Key Recommendations:

  • Early identification of high-risk Indigenous and Māori women
  • Culturally safe antenatal care (AHWs, interpreters)
  • Early referral to tertiary centres
  • Culturally appropriate postpartum support
  • Community-based follow-up and support

Clinical Pearls and Pitfalls

Clinical Pearls

  1. Early recognition is critical: Signs of hypovolaemia (tachycardia, cool peripheries) precede hypotension in healthy pregnant women.

  2. Treat bleeding while diagnosing: Start uterotonics and resuscitation immediately, don't wait for full assessment.

  3. Bimanual uterine massage: Immediate, effective, cheap - always perform while waiting for uterotonics.

  4. TXA timing: Give within 3 hours of delivery, avoid if greater than 3 hours.

  5. Fibrinogen is critical: Maintain greater than 2 g/L, early cryoprecipitate improves outcomes.

  6. Balloon tamponade: Highly effective (80-90%), avoids surgery in most cases.

  7. Multidisciplinary team: Obstetrician, anaesthetist, haematologist, blood bank, intensive care.

  8. Massive transfusion: Activate early (1:1:1 ratio), avoid excessive crystalloid.

  9. Uterine palpation: Always palpate uterus - boggy uterus = atony, firm uterus = other cause.

  10. Placenta inspection: Always inspect placenta for completeness.

Pitfalls to Avoid

  1. Underestimating blood loss: Visual estimation underestimates by 30-50%, use quantitative methods.

  2. Delayed TXA: Must give within 3 hours of delivery.

  3. Excessive crystalloid: Contributes to dilutional coagulopathy, use blood products early.

  4. IV ergometrine: ALWAYS give IM, never IV (risk of severe hypertension, cerebrovascular accident).

  5. Carboprost in asthma: Contraindicated, always check asthma history.

  6. Inadequate analgesia: Manual removal of placenta requires excellent analgesia.

  7. Ignoring concealed haemorrhage: Uterine rupture, broad ligament haematoma - look for signs (pain, shock, mass).

  8. Delaying hysterectomy: If patient unstable and refractory to other measures, proceed to hysterectomy.

  9. Forgetting uterine massage: Continue massage intermittently for 2 hours postpartum.

  10. Ignoring temperature: Hypothermia impairs coagulation, maintain normothermia.

Assessment

SAQ 1 (15 marks)

Scenario: A 32-year-old primigravida at 38 weeks gestation undergoes an emergency caesarean section for fetal distress. Delivery is uneventful, but she develops significant bleeding 30 minutes postpartum. Estimated blood loss is 1200 mL. The uterus is boggy, and there is no evidence of trauma or retained placenta.

Questions:

(a) What is your immediate management plan? (6 marks)

(b) What uterotonics are available, and what are their doses, mechanisms, and adverse effects? (5 marks)

(c) If bleeding continues despite uterotonics, what are the next steps in management? (4 marks)

Model Answer: SAQ 1

(a) Immediate management (6 marks)

  1. Call for help: Activate obstetric haemorrhage team (obstetrician, anaesthetist, midwives, theatre staff) (1 mark)

  2. ABC assessment and resuscitation:

    • High-flow oxygen (15 L/min via non-rebreather mask)
    • Two large-bore IV cannulae (14G/16G)
    • Rapid fluid resuscitation (initial crystalloid 500-1000 mL, then blood products)
    • Vital signs monitoring (continuous ECG, SpO2, BP, urine output)
    • Patient positioning: left lateral tilt 15-30° (2 marks)

  3. Uterine assessment:

    • Bimanual uterine massage (immediate)
    • Palpate uterine tone (boggy = atony)
    • Exclude retained placenta or membranes
    • Inspect genital tract for trauma (1 mark)

  4. Uterotonics (first-line):

    • Oxytocin 5-10 IU IV bolus (over 5 minutes) followed by 40 IU in 500 mL infusion (100-200 mL/hr)
    • Continue bimanual uterine massage until uterus firm (1 mark)

  5. Laboratory investigations:

    • FBC, coagulation profile, fibrinogen
    • Group and screen (cross-match 4-6 units)
    • Baseline Hb, platelets, coagulation (1 mark)

(b) Uterotonics (5 marks)

  1. Oxytocin:

    • Dose: 5-10 IU IV bolus + 40 IU infusion
    • Mechanism: Oxytocin receptor agonist, stimulates uterine contraction
    • Adverse effects: Hypotension (bolus), tachycardia, fluid overload, water intoxication (1 mark)

  2. Ergometrine:

    • Dose: 0.2 mg IM (repeat 15 minutes later if needed)
    • Mechanism: 5-HT receptor agonist, potent uterine smooth muscle contraction
    • Adverse effects: Hypertension, headache, nausea, vomiting, coronary vasospasm
    • Contraindication: Hypertension, pre-eclampsia, cardiac disease (1 mark)

  3. Carboprost (Hemabate):

    • Dose: 250 µg IM (repeat 15 minutes later, maximum 2 g total = 8 doses)
    • Mechanism: PGF2α analogue, strong uterine contraction
    • Adverse effects: Bronchospasm, hypertension, nausea, vomiting, diarrhoea, fever
    • Contraindication: Asthma, severe cardiac/respiratory disease (1 mark)

  4. Misoprostol:

    • Dose: 600-1000 µg sublingual or rectal
    • Mechanism: PGE1 analogue, uterine contraction
    • Adverse effects: Fever, shivering, nausea, vomiting, diarrhoea
    • Advantage: Stable at room temperature, inexpensive (1 mark)

  5. Tranexamic acid:

    • Dose: 1 g IV bolus + 1 g infusion over 8 hours (if below 3 hours from delivery)
    • Mechanism: Inhibits plasminogen activation (antifibrinolytic)
    • Evidence: WOMAN trial - 19% reduction in death from bleeding (1 mark)

(c) Next steps if bleeding continues (4 marks)

  1. Second-line measures:

    • Continue uterotonics (add second and third-line agents)
    • Continue bimanual uterine massage
    • Consider misoprostol if not already given (1 mark)

  2. Balloon tamponade:

    • Insert Bakri tamponade balloon or Foley catheter (30-50 Fr)
    • Inflate with saline (300-500 mL, titrate to bleeding control)
    • Secure balloon, leave in situ 12-24 hours
    • Perform ultrasound to confirm correct placement (1 mark)

  3. Massive transfusion protocol:

    • Activate massive transfusion (1:1:1 ratio - RBC:FFP:Platelets)
    • Maintain fibrinogen greater than 2 g/L (cryoprecipitate or fibrinogen concentrate)
    • Maintain platelets greater than 75 × 10⁹/L
    • Maintain ionised calcium greater than 1.0 mmol/L (1 mark)

  4. Surgical options (if refractory):

    • Uterine compression sutures (B-Lynch suture)
    • Uterine artery ligation (bilateral)
    • Internal iliac (hypogastric) artery ligation
    • Arterial embolisation (if patient stable)
    • Hysterectomy (life-threatening refractory bleeding) (1 mark)

SAQ 2 (15 marks)

Scenario: A 28-year-old multiparous woman presents to a rural hospital at 34 weeks gestation with painless vaginal bleeding. Ultrasound confirms placenta praevia major. She undergoes an emergency caesarean section for massive antepartum haemorrhage. Estimated blood loss is 2500 mL, and she is haemodynamically unstable (SBP 85/50, HR 130). Coagulation profile shows fibrinogen 1.2 g/L.

Questions:

(a) What is your immediate resuscitation plan? (5 marks)

(b) How would you manage her coagulopathy? (4 marks)

(c) What are the indications and techniques for uterine compression sutures? (3 marks)

(d) If bleeding continues, what are the surgical options available? (3 marks)

Model Answer: SAQ 2

(a) Immediate resuscitation (5 marks)

  1. Activate massive transfusion protocol:

    • Call blood bank, activate emergency blood supply
    • 1:1:1 ratio (RBC:FFP:Platelets) - 4 U PRBCs + 4 U FFP + 1 pool platelets initially
    • O-negative uncrossmatched initially, switch to group-specific when available (1 mark)

  2. IV access and fluids:

    • Two large-bore cannulae (14G/16G) or rapid infuser
    • Maximum 1-2 L crystalloid before blood products
    • Aggressive blood product administration (1 mark)

  3. Haemodynamic support:

    • High-flow oxygen (15 L/min non-rebreather mask)
    • Continuous ECG, SpO2, BP monitoring
    • Left lateral tilt (15-30°) - aortocaval compression
    • Consider vasopressor (noradrenaline) if hypotension persists (1 mark)

  4. Uterotonic therapy:

    • Oxytocin 5-10 IU IV bolus + infusion
    • Ergometrine 0.2 mg IM (if not hypertensive)
    • Carboprost 250 µg IM (if no asthma)
    • Bimanual uterine massage (1 mark)

  5. Monitoring and investigations:

    • Arterial line (accurate BP, frequent blood sampling)
    • Foley catheter (urine output greater than 0.5 mL/kg/hr)
    • Repeat FBC, coagulation, fibrinogen every 30-60 minutes
    • ABG (lactate, acid-base status) (1 mark)

(b) Management of coagulopathy (4 marks)

  1. Fibrinogen replacement (critical):

    • Fibrinogen 1.2 g/L - significantly low (target greater than 2 g/L)
    • Cryoprecipitate 2-3 pools (each pool raises 1 g/L) OR
    • Fibrinogen concentrate 3-4 g IV
    • Repeat fibrinogen level, maintain greater than 2 g/L (1 mark)

  2. Fresh Frozen Plasma:

    • 15-20 mL/kg (4-6 U for adult)
    • Replace clotting factors, correct prolonged INR/APTT
    • Given as part of massive transfusion (1:1:1 ratio) (1 mark)

  3. Platelet transfusion:

    • Target greater than 75 × 10⁹/L (or greater than 100 × 10⁹/L if ongoing bleeding)
    • 1 pool (5 U) or 1 apheresis unit
    • Given with FFP (part of 1:1:1 ratio) (1 mark)

  4. Tranexamic acid:

    • 1 g IV bolus over 10 minutes + 1 g infusion over 8 hours
    • Give if within 3 hours of delivery (most beneficial)
    • Antifibrinolytic, reduces bleeding (1 mark)

(c) Uterine compression sutures (3 marks)

Indications:

  • Atonic PPH refractory to uterotonics and balloon tamponade
  • Patient stabilised but ongoing bleeding
  • Desire to preserve fertility (avoid hysterectomy) (1 mark)

B-Lynch suture technique:

  • Hysterotomy (if caesarean) or vaginal uterine incision (if vaginal delivery)
  • No. 2 absorbable suture on large needle
  • Vertical mattress sutures compressing uterus
  • "Figure-of-8" compression to reduce uterine volume
  • Sutures pass through uterine wall, avoiding uterine vessels
  • Apply compression until bleeding controlled, tie sutures
  • Close uterus (if hysterotomy performed) (1 mark)

Evidence and complications:

  • 75-90% success rate
  • Avoids hysterectomy in majority of cases
  • Complications: Uterine necrosis (rare, 1-2%), uterine synechiae, infertility
  • Contraindications: Uterine trauma, uterine infection, coagulopathy (1 mark)

(d) Surgical options if bleeding continues (3 marks)

  1. Uterine artery ligation:

    • Bilateral ligation of uterine arteries at origin from internal iliac
    • 85-90% success rate
    • Preserves fertility (1 mark)

  2. Internal iliac (hypogastric) artery ligation:

    • Ligation distal to posterior division
    • 70-80% success rate
    • Lower success than uterine artery ligation alone
    • Complications: Buttock claudication, sciatic nerve injury (1 mark)

  3. Arterial embolisation:

    • Femoral artery puncture, selective catheterisation of uterine arteries
    • Embolic material (gelatin sponge, coils)
    • 80-90% success rate
    • Requires interventional radiology, patient must be stable (1 mark)

  4. Hysterectomy:

    • Indication: Life-threatening refractory bleeding
    • Subtotal (faster, less blood loss) vs total (if cervical trauma)
    • Definitive control of bleeding (bonus mark)

Viva 1 (20 marks)

Examiner: A 32-year-old primigravida undergoes a normal vaginal delivery at 39 weeks gestation. Immediately postpartum, she develops significant vaginal bleeding. The estimated blood loss is 800 mL. How would you assess and manage this patient?

Model Answer: Viva 1

Candidate: This is a primary postpartum hemorrhage. My approach would be:

Immediate Assessment (ABC):

  1. Call for help: Activate the obstetric haemorrhage team immediately - obstetrician, anaesthetist, midwives, theatre staff.

  2. Airway and Breathing:

    • Assess airway patency
    • Administer high-flow oxygen (15 L/min via non-rebreather mask)
    • Monitor respiratory rate, oxygen saturation

  3. Circulation:

    • Establish two large-bore IV cannulae (14G or 16G)
    • Check heart rate and blood pressure
    • Assess peripheral perfusion (capillary refill, skin colour)
    • Insert Foley catheter for urine output monitoring
    • Commence fluid resuscitation (crystalloid 500-1000 mL initially)
    • Arrange urgent blood tests: FBC, coagulation profile, fibrinogen, group and screen

  4. Specific Obstetric Assessment:

    • Uterine tone: Perform bimanual uterine massage - assess if uterus is boggy (atony) or firm
    • Uterine size: Palpate fundal height - enlarged uterus suggests retained placenta or clots
    • Placenta: Inspect placenta for completeness - ensure no succenturiate lobes retained
    • Genital tract: Visualise perineum and vaginal introitus under good lighting - look for lacerations or trauma
    • Bleeding: Assess ongoing bleeding - colour, clot formation, flow rate

Immediate Management:

  1. Uterotonics (first-line):

    • Oxytocin 5-10 IU IV bolus over 5 minutes
    • Oxytocin 40 IU in 500 mL IV infusion at 100-200 mL/hr
    • Continue bimanual uterine massage until uterus firm and bleeding controlled

  2. If bleeding continues:

    • Add ergometrine 0.2 mg IM (if not hypertensive)
    • Consider carboprost 250 µg IM (if no asthma)
    • Consider misoprostol 600-1000 µg sublingual or rectal

  3. Tranexamic acid:

    • 1 g IV bolus over 10 minutes + 1 g infusion over 8 hours
    • Most effective if given within 3 hours of delivery

  4. Monitoring:

    • Continuous ECG, SpO2, BP
    • Urine output (target greater than 0.5 mL/kg/hr)
    • Repeat FBC and coagulation profile at 30-60 minutes if ongoing bleeding

Differential Diagnosis (The 4 T's):

  1. Tone (uterine atony): Most common cause (70-80%)

    • Risk factors: Overdistended uterus (twins, polyhydramnios, macrosomia), prolonged labour, grand multiparity, magnesium sulfate use, anaemia
    • Diagnosis: Boggy uterus, responds to uterotonics and massage

  2. Trauma (genital tract): 15-20%

    • Cervical lacerations, vaginal lacerations, perineal tears, uterine rupture
    • Diagnosis: Visualise lacerations, uterine tenderness, abnormal fetal heart rate (if ruptured)

  3. Tissue (retained placenta): 10%

    • Retained placenta or membranes
    • Diagnosis: Incomplete placenta on inspection, boggy uterus with clots, ultrasound confirmation

  4. Thrombin (coagulopathy): 5-10%

    • Dilutional coagulopathy, DIC, pre-existing coagulopathy
    • Diagnosis: Oozing, prolonged INR/APTT, low fibrinogen, low platelets

If Bleeding Continues (escalation):

  1. Second-line uterotonics: Add all uterotonics (oxytocin, ergometrine, carboprost, misoprostol)

  2. Balloon tamponade:

    • Insert Bakri tamponade balloon or Foley catheter (30-50 Fr)
    • Inflate with saline (300-500 mL)
    • Apply traction, secure balloon
    • Perform ultrasound to confirm placement

  3. Massive transfusion protocol:

    • Activate if blood loss greater than 1500 mL or ongoing bleeding despite uterotonics
    • 1:1:1 ratio (RBC:FFP:Platelets)
    • Maintain fibrinogen greater than 2 g/L, platelets greater than 75 × 10⁹/L, ionised calcium greater than 1.0 mmol/L

  4. Surgical options:

    • Uterine compression sutures (B-Lynch suture)
    • Uterine artery ligation
    • Internal iliac artery ligation
    • Arterial embolisation (if patient stable)
    • Hysterectomy (refractory, life-threatening bleeding)

Viva 2 (20 marks)

Examiner: A 24-year-old G2P1 woman at 36 weeks gestation presents to the emergency department with severe abdominal pain and vaginal bleeding. She reports decreased fetal movements. On examination, she is pale, HR 130, BP 85/50. The uterus is tense and tender. What is your differential diagnosis, and how would you manage this patient?

Model Answer: Viva 2

Candidate: This is a critical obstetric emergency. My differential diagnosis is:

Differential Diagnosis:

  1. Placental abruption: Most likely diagnosis

    • Classic triad: Abdominal pain, vaginal bleeding, uterine tenderness
    • Signs of hypovolaemic shock (HR 130, BP 85/50, pale)
    • Tense, tender uterus (Couvelaire uterus)
    • Decreased fetal movements (possible fetal distress or demise)

  2. Uterine rupture:

    • Previous caesarean section (G2P1 - possibly previous CS)
    • Severe abdominal pain
    • Vaginal bleeding
    • Signs of shock
    • May have fetal distress

  3. Placenta praevia with bleeding:

    • Painless vaginal bleeding (usually)
    • Possible major haemorrhage
    • Less likely given abdominal pain and uterine tenderness

  4. Amniotic fluid embolism:

    • Sudden collapse, hypotension
    • Usually during labour or immediately postpartum
    • Less likely given antepartum presentation

  5. Vasa praevia:

    • Fetal bleeding (maternal bleeding minimal)
    • Fetal distress
    • Rupture of membranes triggers bleeding

Immediate Management:

  1. ABC assessment and resuscitation:

    • Airway: High-flow oxygen (15 L/min non-rebreather mask)
    • Breathing: Assess respiratory rate, SpO2
    • Circulation:
      • Two large-bore IV cannulae (14G/16G)
      • Crystalloid 500-1000 mL initially
      • Call blood bank - activate massive transfusion protocol
      • Cross-match 4-6 units PRBCs, 4 U FFP, 1 pool platelets
    • Disability: GCS, level of consciousness
    • Exposure: Full examination, maintain temperature

  2. Monitoring:

    • Continuous ECG, SpO2, BP
    • Foley catheter (urine output greater than 0.5 mL/kg/hr)
    • Consider arterial line (unstable, accurate BP)
    • Consider central venous line (massive transfusion)

  3. Fetal assessment:

    • Continuous fetal monitoring (CTG) if possible
    • Urgent obstetric ultrasound (if available)
    • Assess fetal heart rate and movements

  4. Immediate interventions:

    • Call for help: Activate obstetric emergency team (obstetrician, anaesthetist, midwives, theatre staff)
    • Call theatre: Prepare for emergency caesarean section
    • Notify neonatal team: Potential for neonatal resuscitation

Diagnosis:

  1. Focused history:

    • Previous caesarean section? (uterine rupture risk)
    • Trauma? (placental abruption risk)
    • Hypertension, pre-eclampsia? (placental abruption risk)
    • Pain characteristics (abruption: constant, severe; rupture: tearing)

  2. Examination:

    • Abdominal palpation: Uterine height, tenderness, contractions
    • Fetal parts palpable? (possible uterine rupture)
    • Vaginal examination: Under strict aseptic technique, assess for dilatation, placental tissue (if previa)
    • Speculum examination: Assess bleeding source, cervical dilation (avoid digital exam if placenta praevia suspected)

  3. Investigations:

    • Ultrasound: Placental location (previa vs abruption), fetal heart rate, uterine integrity (rupture)
    • Kleihauer-Betke test: Fetal-maternal haemorrhage (abruption)
    • Laboratory:
      • FBC (Hb, platelets)
      • Coagulation profile (PT, INR, APTT, fibrinogen) - abruption causes DIC
      • Group and screen
      • ABG (lactate, acid-base)

Specific Management for Placental Abruption:

  1. Delivery: Definitive management is delivery

    • Emergency caesarean section if:
      • Fetal distress
      • Maternal haemodynamic instability
      • Significant vaginal bleeding
    • Vaginal delivery if:
      • Fetal demise
      • Maternal stable
      • Dilatation adequate
      • Haemorrhage controlled

  2. Coagulopathy management (DIC is common with abruption):

    • Fibrinogen: Maintain greater than 2 g/L (cryoprecipitate 2-3 pools or fibrinogen concentrate 3-4 g)
    • FFP: 15-20 mL/kg
    • Platelets: Maintain greater than 75 × 10⁹/L (or greater than 100 × 10⁹/L if bleeding)
    • 1:1:1 ratio massive transfusion

  3. Resuscitation:

    • Aggressive fluid resuscitation (blood products preferred over crystalloid)
    • Maintain systolic BP greater than 90 mmHg
    • Maintain urine output greater than 0.5 mL/kg/hr
    • Correct hypothermia, acidosis, hypocalcaemia

Specific Management for Uterine Rupture:

  1. Emergency laparotomy and caesarean section
  2. Uterine repair or hysterectomy
  3. Massive transfusion protocol
  4. Neonatal resuscitation

Complications:

  1. Maternal:

    • Hypovolaemic shock
    • Coagulopathy (DIC)
    • Acute kidney injury
    • Hypoxic-ischaemic brain injury
    • Hysterectomy
    • Death

  2. Fetal:

    • Hypoxic-ischaemic encephalopathy
    • Fetal demise
    • Neonatal depression

Prognosis:

  • Maternal mortality: 1-3% (with prompt management)
  • Fetal/neonatal mortality: 10-30% (abruption), 5-15% (uterine rupture)
  • Key to good outcome: Early recognition, rapid delivery, aggressive resuscitation, multidisciplinary team

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