Placental Abruption with DIC

Placental abruption is premature separation of a normally implanted placenta, complicating about 0.4 to 1% of pregnancies. Disseminated intravascular coagulation (DIC) develops in about 10 to 20% of severe abruptions (those with fetal death in about 30%).

Release of tissue factor (thromboplastin) from decidua and placenta into the maternal circulation triggers massive thrombin generation, fibrinogen consumption, hyperfibrinolysis, and factor depletion, with microvascular thrombosis and bleeding. Hypofibrinogenaemia is the earliest and most useful marker.

Complications:

• Haemorrhagic shock.
• Acute kidney injury (acute tubular necrosis, cortical necrosis).
• Sheehan syndrome and ARDS.
• Fetal hypoxia and death.
• Maternal death (about 1% in severe cases).

Risk factors:

• Previous abruption (recurrence about 10 to 25%).
• Pre-eclampsia and hypertension.
• Trauma (including domestic violence).
• Cocaine and smoking.
• PPROM and chorioamnionitis.
• Thrombophilia.
• Multiparity and older age.
• Polyhydramnios with rapid decompression.
• Uterine fibroids.

• Vaginal bleeding (dark blood; may be concealed in up to 20 to 35%) with constant abdominal pain, a tense "woody" tender uterus, and uterine hypertonus or frequent contractions
• Fetal distress: bradycardia, late decelerations, sinusoidal pattern, or fetal death
• Maternal shock out of proportion to visible blood loss; Couvelaire uterus (blood infiltration into the myometrium)
• DIC: bleeding from venepuncture sites, mucosa, wounds, haematuria, petechiae, oozing from surgical sites, and failure of blood to clot; organ failure (renal, hepatic, respiratory)
• Back pain, preterm labour

• Clinical diagnosis; ultrasound is insensitive (detects retroplacental clot in only about 25 to 50%)
• Blood tests: full blood count, fibrinogen, PT, aPTT, D-dimer (markedly raised), fibrin degradation products, platelets, urea, creatinine, liver function, lactate, group and crossmatch, and Kleihauer-Betke test (fetomaternal haemorrhage)
• Fibrinogen below 2 g/L in pregnancy is a red flag; below 1 g/L predicts severe haemorrhage
• Rapid bedside clot observation test: a clot that fails to form in 7 to 10 minutes suggests fibrinogen below 1 g/L
• ROTEM or TEG for rapid assessment of fibrinogen function and fibrinolysis
• Cardiotocography for fetal status
• ISTH DIC score (platelet count, D-dimer, PT, fibrinogen) of 5 or more confirms overt DIC; pregnancy modified score

• Activate the major obstetric haemorrhage protocol: two large bore cannulae, oxygen, bloods, crossmatch 4 to 6 units, warm fluids, and urinary catheter.
• Aggressive resuscitation: warmed crystalloid initially, with early transfusion of red cells and component therapy in a ratio approaching 1:1:1 (red cells, fresh frozen plasma, platelets).
• Targets and adjuncts:
  • Cryoprecipitate or fibrinogen concentrate (target fibrinogen above 2 g/L; fibrinogen concentrate 2 to 4 g, or cryoprecipitate 10 units (2 pools)).
  • Platelets above 50,000/microlitre, and PT/aPTT ratio below 1.5.
  • Tranexamic acid 1 g IV over 10 minutes, repeated after 30 minutes if bleeding continues.
  • Correct calcium (calcium gluconate 10 mL of 10% IV) and temperature.
  • Use cell salvage when available.
  • Recombinant factor VIIa is a last resort therapy.
• Delivery: immediate delivery in severe abruption with fetal compromise. Perform emergency caesarean if the fetus is alive and viable, accepting that DIC increases surgical bleeding; correct coagulopathy in parallel.
• If the fetus is dead and the mother is stable, use vaginal delivery with amniotomy and oxytocin. Aim for rapid delivery (within 6 hours) with continuous coagulation monitoring.
• Postpartum haemorrhage prevention: oxytocin 5 to 10 IU slow IV, then infusion 40 IU in 500 mL.
• Additional uterotonics: carboprost 250 micrograms IM every 15 minutes up to 8 doses unless asthmatic; misoprostol 800 micrograms. Use uterine massage and compression.
• For refractory bleeding: Bakri balloon, uterine compression sutures, uterine artery embolisation, or hysterectomy. Couvelaire uterus usually still contracts and does not require hysterectomy.
• Renal protection: maintain urine output above 0.5 mL/kg/hour, avoid nephrotoxins, and use renal replacement therapy for AKI.
• Anti-D immunoglobulin for RhD-negative women (dose by Kleihauer-Betke).
• ICU monitoring for at least 24 to 48 hours. Give thromboprophylaxis after bleeding is controlled (enoxaparin 40 mg daily when haemostasis restored).
• Follow up: counselling regarding recurrence (about 10 to 25%), pre-conception optimisation, aspirin in subsequent pregnancy, and early surveillance. Screen for Sheehan syndrome (failure of lactation, amenorrhoea, hypopituitarism).