APH and placental abruption

Question 1

Define ‘antepartum haemorrhage’

Answer 1

Bleeding from the genital tract from 24+0 weeks until delivery

Question 2

What % of pregnancies are affected by APH?

Answer 2

3-5%

Question 3

What % of pregnancies affected by APH are considered low risk?

Answer 3

70%

Question 4

List your differential diagnoses for APH under the headings of:

• Uterine
• Cervical
• Vaginal

Answer 4

• Uterine causes:
  
  • Placental edge bleeding
  • Placenta praevia 20%
  • Placental abruption 30%
  • Uterine rupture (rare)
  • Vasa praevia (rare)
• Cervical causes:
  
  • Bloody show
  • Cervical ectropion
  • Cervical polyp
• Vaginal causes:
  
  • Vaginitis
  • Vaginal trauma
  • Warts
  • Polyps

Question 5

What are the risk factors for placental abruption?

Answer 5

• Previous placental abruption:
  
  • Risk of recurrence 4% if one previous abruption.
  • Risk of recurrence 19-25% if two previous abruptions.
• Abdominal trauma.
• Maternal factors:
  
  • Pre-eclampsia
  • Cocaine and amphetamine use during pregnancy.
  • Smoking
  • AMA
  • ART
  • Low BMI
  • Multiparity
  • Maternal thrombophilias (factor V Leiden, prothrombin 20210A)
• Fetal factors:
  
  • IUGR
  • Non-vertex presentations
  • Polyhydramnios
• Obstetric factors:
  
  • Premature rupture of membranes
  • Intrauterine infection
  • First trimester bleeding
  • Subchorionic haematoma

Question 6

What are the maternal and fetal effects of APH?

Answer 6

Maternal effects:

• Anaemia
• Infection
• Shock
• Renal tubular necrosis
• DIC
• PPH
• Prolonged hospital stay
• Psychological sequelae
• Complications of blood transfusion

Fetal effects:

• IUGR
• Stillbirth
• Preterm birth
• Fetal hypoxia

Question 7

Evaluate the utility of ultrasound in diagnosing a placental abruption.

Answer 7

Not useful for diagnosing a placental abruption because:

• Low sensitivity 25% i.e. it fails to detect 75% of cases.
• High specificity 96% i.e. when USS suggests an abruption, the likelihood that there is an abruption is high.
• Positive predictive value: 88%
• Negative predictive value 53%

Question 8

Discuss your considerations around tocolysis in the context of APH:

Answer 8

• Senior obstetrician should may decision regarding initiation of tocolysis in event of APH, especially if:
  
  • Very preterm
  • Needing transfer to hospital that can provide NICU care
  • Not completed full course of steroids
• Absolute contraindication: placental abruption.
• Relative contraindication: mild bleeding from placenta praevia.
• Choice of tocolysis if to be used:
  
  • Avoid nifedipine as causes maternal hypotension.

Question 9

Regarding massive transfusion protocol:

In suspected DIC, how much fresh frozen plasma (FFP) and cryoprecipitate can be given while awaiting coagulation study results?

Answer 9

• 4 units of FFP
• 10 units of cryoprecipitate