Placental abruption - ?finished Flashcards
What is placental abruption and what are the causes? [2]
What are the two types? [2]
Placental abruption refers to when the placenta separates from the wall of the uterus during pregnancy.
- The site of attachment can bleed extensively after the placenta separates.
- Unknown cause
Types:
- Placental abruption can be either concealed (bleeding remains within the uterus and is not visible) or revealed (visible vaginal bleeding).
When does placental abruption occur in the pregnancy? [1]
Abruption is more likely to occur in the last trimester, particularly during the last few weeks prior to birth.
Name 5 RF for placental abruption [5]
Alcohol ingestion:
- it accumulates on the fetus and amniotic fluid after crossing the placenta. It causes vasospasm in the placenta and umbilical cord, which might lead to abruption of the placenta.
Advanced maternal age
Cigarette smoking
Pre-eclampsia
Cocaine usage during pregnancy
- the high blood pressure and increased levels of catecholamines released by cocaine are considered to be responsible for the vasoconstriction in the uterine blood vessels that causes placental separation and abruption.
Abdominal trauma:
- injuries cause separation of the placental attachment from decidua.
Describe the clinical features of placental abruption
The typical presentation of placental abruption is sudden constant pain with or without dark red vaginal bleeding (>24 weeks gestation). The pain is continuous
Shock (hypotension and tachycardia)
Characteristic “woody” abdomen on palpation, suggesting a large haemorrhage. Uterus is extremely hard and tender, and it does not relax.
Back pain
NB: In 20% of cases it is possible for the blood to become trapped inside the uterus (concealed), so even with a severe placental abruption, there might be no visible bleeding.
Describe the investigations used for placental abruption
Ultrasound Imaging
- should have an ultrasound scan performed to confirm or exclude placenta praevia if the placental site is not already known.
Cardiotocograph (CTG):
- should be performed in women above 26 weeks gestation to assess fetal wellbeing.
- Abruption can result in fetal hypoxia and abnormalities of the fetal heart rate pattern
Blood Tests
Describe the difference in pathophysiology of important ddx to placental abruption [1]
Abnormal vaginal bleeding during the second half of pregnancy is usually due to either placental abruption or placenta praevia. It is important to differentiate these two conditions.
- With placental abruption, the placenta partially or completely detaches itself from the uterine wall before delivery
- With placenta praevia, the placenta is located over or near the cervix, in the lower part of the uterus.
Describe the difference in speed of presentation of placental abruption and placental praevia [1]
placental abruption:
- onset of symptoms is acute and severe
- Haemorrhage may be visible or concealed
- abdominal pain are intense and acute
- Fetal hearts sounds are absent or may show distress
placental praevia:
- quiet and insidious
- Haemorrhage may be external and visible
- Fetal hearts sounds are normal
The RCOG guideline (2011) defines the severity of antepartum haemorrhage as: [4]
Spotting: spots of blood noticed on underwear
Minor haemorrhage: less than 50ml blood loss
Major haemorrhage: 50 – 1000ml blood loss
Massive haemorrhage: more than 1000 ml blood loss, or signs of shock
Describe what is meant by a concealed abruption [1]
Concealed abruption is where the cervical os remains closed, and any bleeding that occurs remains within the uterine cavity. The severity of bleeding can be significantly underestimated with concealed haemorrhage.
Describe the mx of placental abruption
Initial resuscitation
Delivery of baby: women with antepartum haemorrhage and associated maternal and/or fetal compromise are required to be delivered immediately
- But not if < 37 weeks or > 37 weeks but only spotting or mucus streaks of blood
- Minor or major antepartum bleeding = induce labour for normal vaginal delivery
Post natal: it is highly recommended to provide active management of the third stage of labour in these patients for the prevention of postpartum haemorrhage.
The risk of preterm births is increased in placental abruption and therefore RCOG suggests a single dose of [] may offer between 24th and 34th weeks of gestation.
Corticosteroids: the risk of preterm births is increased in placental abruption and therefore RCOG suggests a single dose of corticosteroid may offer between 24th and 34th weeks of gestation.
What sort of prophylaxis do you need to think about in bleeding pregnant women [1]
Rhesus-D negative women require anti-D prophylaxis when bleeding occurs.
Which test can be used to determine how much fetal blood is mixed with maternal? [1]
A Kleihauer test is used to quantify how much fetal blood is mixed with the maternal blood, to determine the dose of anti-D that is required.
A woman who is 35-weeks pregnant presents with lower abdominal pain and a small amount of vaginal bleeding. Her blood pressure is 86/60 mmHg and pulse 114/min - placental abruption
QuesMed flashcard
How is placental abruption diagnosed?
Placental abruption is diagnosed clinically.
An USS is performed to rule OUT placenta praevia
