With placental abruption, blood loss may not always be visible per vaginam and can be dangerously underestimated.
About
- Placental abruption refers to the separation of the placenta from the uterine wall before the baby is born.
- It is a leading cause of antepartum haemorrhage (bleeding before delivery).
Aetiology
- Occurs in 1-2% of pregnancies, where bleeding occurs into the decidua basalis (the maternal part of the placenta).
- Blood loss can be severe and rapid due to the high uterine blood supply, which is 600-800 mL/min at term.
Risk Factors for Abruption
- Pre-eclampsia
- Chorioamnionitis
- Cocaine use
- Race: Higher risk in Black women than White women
- Male fetus
- Hypertension
- Polyhydramnios (excess amniotic fluid)
- Smoking
- Trauma (e.g., from a car accident or fall)
Clinical Features
- Vaginal bleeding (although sometimes blood loss is concealed).
- Severe, constant abdominal or back pain.
- Uterine contractions.
- Tense and tender uterus.
- Fetal distress (abnormal or absent fetal heartbeats).
Possible Differential Diagnoses
- Uterine rupture
- Appendicitis
- Chorioamnionitis
Investigations
- Ultrasound scan (USS) can diagnose placental abruption in only 50% of cases. A clinical diagnosis is often made based on symptoms.
Management
- Supportive care: IV access, blood transfusion, and stabilization of the mother.
- Fetal viability: Assess the fetus to determine if it is still viable.
- Steroids: Administer corticosteroids to promote fetal lung maturity if preterm delivery is anticipated.
- Monitor for coagulopathy: Keep a close watch for signs of disseminated intravascular coagulation (DIC).
- Delivery: Vaginal delivery can be considered if both the mother and fetus are stable.
- Emergency C-section: If there is significant haemorrhage or fetal distress, an immediate caesarean section is required.
Complications
- Hemorrhagic shock: Severe blood loss can lead to shock.
- Disseminated intravascular coagulation (DIC): blood clots form throughout the body, leading to bleeding elsewhere.
- Acute tubular necrosis (ATN): Ischaemic damage to the maternal kidneys due to severe blood loss.
- Couvelaire uterus: Blood leaks into the uterine muscle, causing uterine atony and potential complications during delivery.