Mastering Postpartum Haemorrhage for SCE: A Clinical Guide

Postpartum Haemorrhage (PPH) is a critical obstetric emergency and a leading cause of maternal mortality worldwide. For candidates preparing for the Specialty Certificate Examination (SCE), a comprehensive understanding of PPH – its causes, timely diagnosis, and effective management – is paramount. This guide will distill the essential knowledge required to ace PPH scenarios in your SCE.

Defining PPH: Know the Numbers

PPH is defined as a blood loss of 500 ml or more within 24 hours after a vaginal birth, or 1000 ml or more after a Caesarean section. It can be further classified:

• Primary PPH: Occurs within the first 24 hours after birth.

• Secondary PPH: Occurs more than 24 hours and up to 12 weeks postpartum.

While these definitions are useful, remember that any blood loss that causes hemodynamic instability or requires intervention is clinically significant.

The "4 Ts" of Primary PPH Etiology

Understanding the causes is the first step to effective management. The mnemonic "4 Ts" is invaluable:

1. Tone (Atony): This is the most common cause (70-80%). Uterine atony is the failure of the uterus to contract adequately after birth, leading to persistent bleeding from the placental site. Risk factors include prolonged labour, grand multiparity, multiple pregnancy, polyhydramnios, large baby, rapid labour, chorioamnionitis, and retained placental tissue.

2. Trauma: Accounts for about 20% of cases. This includes lacerations (cervical, vaginal, perineal), uterine rupture, or uterine inversion. Always inspect the birth canal meticulously after birth, especially if bleeding persists despite a well-contracted uterus.

3. Tissue: Retained placental tissue or membranes (10%). Any residual tissue prevents the uterus from contracting effectively. Manual removal of placenta or exploration of the uterine cavity may be necessary.

4. Thrombin: Coagulopathy (1%). Pre-existing bleeding disorders (e.g., von Willebrand disease), HELLP syndrome, DIC (due to severe preeclampsia, amniotic fluid embolism, placental abruption, sepsis), or anticoagulant therapy can all impair clotting, leading to excessive bleeding.

Rapid Assessment and Initial Management: The Golden Hour

Time is of the essence in PPH. A systematic approach is crucial:

1. Call for Help: Activate the PPH protocol/emergency team immediately. Designate roles (e.g., one person for vital signs, one for IV access, one for medication, one for communication).

2. Resuscitate:

   • Airway, Breathing, Circulation (ABC): Ensure patent airway, provide oxygen (10-15 L/min via non-rebreather mask).

   • IV Access: Establish at least two large-bore IV cannulae (14G or 16G).

   • Fluid Resuscitation: Rapid infusion of warm crystalloids (e.g., Normal Saline or Ringer's Lactate) or colloids. Consider blood transfusion early if bleeding is severe or ongoing (request cross-matched blood, O negative if immediate action needed).

   • Monitor Vitals: Closely monitor blood pressure, heart rate, respiratory rate, oxygen saturation, and urine output (catheterise if not already done).

3. Identify and Address Cause (4 Ts simultaneously):

   • Tone: Uterine Massage: Rub the fundus firmly through the abdomen to stimulate contractions. Uterotonic Agents:

     • Oxytocin: First-line. 10 units IM or 5-10 units slow IV bolus, followed by 20-40 units in 500-1000 ml IV fluid at 125 ml/hour (or as per local guidelines).

     • Ergometrine: 0.2-0.5 mg IM or IV. Contraindicated in hypertension, preeclampsia, cardiac disease.

     • Carboprost (Hemabate): 250 mcg IM, repeated every 15-90 minutes up to 8 doses. Contraindicated in asthma.

     • Misoprostol: 800-1000 mcg rectally. Useful when injectables are not available or as an adjunct.

     • Tranexamic Acid: 1g IV over 10 minutes, repeated if necessary after 30 minutes, or within 3 hours if bleeding continues. Should be given within 3 hours of birth for suspected PPH.

   • Trauma: Inspect the cervix, vagina, and perineum carefully. Repair any lacerations. If uterine rupture or inversion is suspected, prepare for immediate surgical intervention.

   • Tissue: Manual removal of retained placental fragments. Uterine exploration for retained tissue or clots. Ultrasound can confirm retained products.

   • Thrombin: Send blood for FBC, coagulation profile (PT, aPTT, fibrinogen), cross-match. Administer blood products (FFP, cryoprecipitate, platelets) as indicated by laboratory results and clinical picture.

Escalation and Advanced Management

If initial measures fail, escalate care:

• Bimanual Uterine Compression: If uterine atony persists.

• Intrauterine Balloon Tamponade (e.g., Bakri balloon): Effective for atonic PPH, applies direct pressure to the bleeding placental site.

• Surgical Options:

  • Uterine Compression Sutures (e.g., B-Lynch suture): Surgical technique to compress the uterus and promote hemostasis.

  • Ligation of Uterine or Internal Iliac Arteries: Reduces blood flow to the uterus.

  • Hysterectomy: A life-saving measure as a last resort in uncontrollable PPH.

Secondary PPH

Causes often include retained placental fragments, endometritis, or rarely, placental site subinvolution. Management involves:

• Antibiotics for suspected infection.

• Uterotonic agents (e.g., oral ergometrine or misoprostol).

• Evacuation of retained products of conception (ERPC) if retained tissue is confirmed.

Key Takeaways for SCE:

• Prioritize ABCs and Resuscitation.

• Systematic application of the 4 Ts.

• Know the doses and contraindications of uterotonic drugs.

• Understand the escalation pathway – from medical to surgical.

• Communication is key: Keep the team informed and calm.

• Practice scenario-based questions to apply your knowledge under pressure.

PPH is a high-stakes topic. By mastering the systematic approach to diagnosis and management, you'll be well-prepared to demonstrate your competence and ensure optimal patient outcomes in your SCE exams.