FRCA Notes

Major Obstetric Haemorrhage

The March 2023 CRQ on this topic (72% pass rate) came with a surprising lack of snarky comment from the examiners about poor knowledge.

Resources

  • Major obstetric haemorrhage occurs in 1 in 270 (3.7/1,000) pregnancies
  • Defined as:
    • Blood loss >1.5L (or >20ml/kg)
    • Drop in haemoglobin concentration by >4g/dL
    • Acute transfusion requirement of >4 units

Classification

  • Ante-partum haemorrhage occurs between 24 weeks and delivery
  • Post-partum haemorrhage occurs after delivery, and can be further classified as:
    • Early (primary) PPH; within 24hrs of delivery
    • Late (secondary) PPH; from 24hrs until 6 weeks post delivery

  • Ante-partum haemorrhage affects 3% of pregnancies

Aetiology

  • 1/3rd due to placental abruption - leads to massive localised consumption of clotting factors and rapidly developing haemostatic incompetence
  • 1/3rd due to placenta praevia ± placenta accreta/increta/percreta
  • 1/3rd due to uterine rupture, or other causes such as ectopic pregnancy

Risk factors

Maternal Utero-placental
Hypertension inc. PET Uterine overdistension
Smoking Placenta praevia
Cocaine or amphetamines Placenta accreta spectrum disorder
Extremes of maternal age Abdominal trauma
Previous abruption
Previous uterine surgery or LSCS


Aetiology

  • Tone (uterine atony; 70% of cases)
  • Thrombin impaired e.g. congenital or acquired coagulopathy (PET, HELLP, IUD, anticoagulants)
  • Tissue e.g. retained placenta or other conceptual products ± puerperal sepsis (particularly causes secondary PPH)
  • Trauma e.g. genital tract trauma, LSCS (emergency > elective), episiotomy, foetal weight >4kg

Risk factors

Maternal Utero-placental Labour-associated
Age >40yrs Multiple pregnancy Prolonged labour
Grand multip (>P4) Polyhydramnios Augmented labour e.g. oxytocin
Obesity Foetal macrosomia Induced labour
Previous PPH Fibroid uterus
Asian ethnicity Placenta praevia/accreta spectrum disorder
Previous LSCS APH
Coagulopathy


Haematological

  • Anaemia
  • Coagulopathy in DIC
  • Complications associated with blood transfusion
  • Sheehan's syndrome
  • PPH (if already suffered APH)

Non-haematological

  • Infection
  • Shock
  • Renal tubular necrosis
  • Death
  • Psychological sequelae
  • Prolonged hospital stay

  • Recite the opening gambit for any clinical emergency:

    • Major obstetric haemorrhage is an anaesthetic & obstetric emergency and I would seek senior anaesthetic support as well as making a rapid but thorough assessment of the patient

  • This will involve making the appropriate 2222 call and activating a major (obstetric) haemorrhage protocol

Immediate

  1.  Maintain and, if necessary, secure the airway via endotracheal intubation

  2.  Administer 100% oxygen and ensure adequate ventilation

  3.  Position the patient in either left-lateral tilt (ante-partum) or head down (post-partum)
    • Secure 2 x large bore IV access (16G or greater)
    • Smash in some uterotonics (see below)
    • Take blood for: Group & cross-match 6 units, FBC, clotting inc. TEG/ROTEM, VBG, U&E
    • Infuse warmed crystalloid up to 2L or O-Rhesus negative blood (1 RBC : 1 FFP)
    • Give tranexamic acid 1g IV over 10mins followed by 1g over 8hrs (smaller doses are ineffective according to the TRACES study)
    • Spin up the cell salvage machine
    • Use point of care tests to monitor Hb (Haemacue) and clotting profile (TEG/ROTEM)
      • Use of VHA was associated with lower total blood loss, but not fewer RBC or plasma transfusions (BJA, 2022)
  • Targets for management are:
Factor Target Intervention
Hb >70g/L pRBC, cell salvage
Haematocrit >0.3 (30%) pRBC, cell salvage
Platelets >75 x 109/L Platelet transfusion
Fibrinogen >2g/L PCC, FFP, fibrinogen concentrate
Ionised calcium (BJA, 2021) >1.0mmol/L IV calcium 10%
Temperature >36°C Active warming
pH Avoid acidosis May necessitate MV

Specific management

  • Uterine atony should be managed with uterotonics, such as:
    • Oxytocin 5IU bolus x 2 ± 10IU/hr infusion
    • Ergometrine 500μg bolus IM/IV
    • Carboprost 250mcg bolus every 15mins up to 2mg
    • Misoprostol 400 - 1000μg PR (may cause hyperthermia or diarrhoea)
  • The surgeons can also be helping out with a variety of surgical interventions:
    • Bi-manual compression or uterine massage
    • Removing retained tissue
    • Suturing traumatic injuries, be they iatrogenic or foetal-induced
    • Intra-uterine balloon tamponade e.g. Bakri balloon or Rusche balloon
    • Uterine compression sutures i.e. B-Lynch sutures
    • IR-guided intra-arterial tamponade/embolisation
    • Pelvic vessel ligation e.g. uterine, internal iliac, ovarian
    • Hysterectomy
    • Aortic compression/clamp/REBOA

Subsequent

  • Some form of HDU or even ICU environment
  • The trifecta of appropriate documentation, a critical incident form and regular, senior, anaesthetic and obstetric follow-up