ANTEPARTUM HAEMORRHAGE Flashcards
What is the definition of antepartum haemorrhage?
Any bleeding from the genital tract that occurs after 24+0 weeks gestation and before birth of the infant.
What is the incidence of antepartum haemorrhage?
3-5%
What are the uterine causes of antepartum haemorrhage (as opposed to lower genital tract causes)?
Placenta praevia
Placental abruption
Vasa praevia
Circumvallate placenta
Remember that up to 50% of cases of APH, no specific cause is found.
What are the lower genital tract causes of antepartum haemorrhage (as opposed to uterine causes)?
Cervical ectropion - extension of endocervical columnar epithelium Cervical polyp Cervical carcinoma Cervicitis Vaginitis Vulval varicosities
Remember that up to 50% of cases of APH, no specific cause is found.
When taking a history from a women with antepartum haemorrhage, what are the key point to ask and why?
Amount of bleeding - Thinking about ressucitation
Triggers - such as sexual intercourse could be a sign of cervical ectropion.
Association with abdominal pain and/or contractions - allows distinction between placenta praevia and a placental abruption
Association with mucoid discharge - could be show signifying beginning of labour
Date and results of last smear - rules out cervical cause
What might you look for on examination of a woman who presents with antepartum haemorrhage?
Maternal: Obs - HR, BP, RR Pallor Uterine tenderness Uterine contractions Cervical abnormalities on speculum Cervical change on contraction (through digital examination - ONLY IF PLACENTA PRAEVIA HAS BEEN EXCLUDED)
Fetal:
Lie/presentation/engagement
Auscultation of heart to determine viability
What investigations should be done for a woman who presents with antepartum haemorrhage?
Haemoglobin Group and save / crossmatch Rhesus status Coagulation profile Kleihauer test U&Es LFTs CTG USS
What is the Kleihauer test?
Examining the blood film of the mother to look for fetal blood cells and hence determine whether there has been feto-maternal haemorrhage (as seen with placental abruption)
What is placenta praevia?
This is when the placenta is wholly or partially attached to the lower uterine segment.
How do we grade the level of placenta praevia?
Traditionally this was done by grading I - IV, however minor and major is more often used nowadays.
I - Encroaches the lower segment - minor
II - Reaches the internal os - minor
III - Overlies the internal os - major
IV - Centrally placed in the lower segment
What are the risk factors for placenta praevia?
Previous placenta praevia
Previous caesarian section
Advanced maternal age
Multiparity
Multiple pregnancy
Presence of a succenturiate (accessory) placental lobe
Smoking
What are the clinical features of placenta praevia?
Painless
Unprovoked
Bright red vaginal bleeding
Absence of labour
At what point in gestation does placenta praevia normally present with antepartum haemorrhage?
In the third trimester, from about 32 weeks
What would you expect to find on digital examination of a woman with antepartum haemorrhage caused by placenta praevia?
YOU MUST NEVER DO A DIGITAL EXAMINATION OF A WOMAN WITH SUSPECTED PLACENTA PRAEVIA AS THIS CAN PROVOKE MASSIVE BLEEDING
What would you expect to find on abdominal examination of a woman with antepartum haemorrhage caused by placenta praevia?
Soft, non tender uterus
Cephalic presentation not engaged
At what point in gestation are most cases of placenta praevia diagnosed?
Low lying placenta is normally visible on routine 20 week ultrasound scan. If low lying placenta is noted at this point then follow up in third trimester should be arranged to make diagnosis.
How do you manage a patient with placenta praevia?
ABCDE approach
Immediate caesarian section if there is maternal or fetal compromise
Steroids to improve fetal lung maturity
Caesarian section is usually advised if placenta is encroaching within 2 cm of cervical os.
What are the complications of placenta praevia?
Increased risk of postpartum haemorrhage
Patients need to be given adequate counselling regarding possible need for medical and surgical measures to control bleeding including hysterectomy.
What is the recurrence rate of placenta praevia?
4-8% with an increased rate of placenta accreta (placental invasion of the myometrium) in each pregnancy.
What is placental abruption?
The placental lining has separated from the uterus of the mother prior to delivery. The placental attachment is disrupted by haemorrhage as blood dissects under the placenta, possibly extending into the amniotic sac or the uterine muscle.
What proportion of pregnancies in the UK are affected by placental abruption?
1%
What are the risk factors for developing placental abruption?
Previous abruption
Advanced maternal age
Multiparity
Maternal hypertension or pre-eclampsia
Abdominal trauma (eg following RTA)
Cigarette smoking
Cocaine use
Lower SEC
External cephalic version (manoeuvre used when baby is lying in wrong position)
What are the clinical features of placental abruption?
Sudden onset abdominal pain
Prolonged contractions
Tenderness of abdomen
Vaginal bleeding (however, not always present as haemorrhage can be internal)
Haemorrhagic shock
Symptoms of pre-eclampsia - headache, blurred vision, nausea, epigastric pain
On examination of a patient with placental abruption, what would you expect to find?
Tender uterus
Tonic contraction felt - makes uterus feel hard
Difficult to palpate fetal parts
BP and proteinuria should be checked due to association between pre-eclampsia and abruption.
What pattern on the CTG would indicate feto-maternal haemorrhage?
Sinusoidal pattern
How would you manage a patient with placental abruption?
ABCDE approach
Immediate caesarian section if there is maternal or fetal compromise
Steroids to improve fetal lung maturity
What are the complications of placental abruption?
Severe haemorrhage - DIC and renal failure
Postpartum haemorrhage which can lead to Sheehan’s syndrome (pituitary necrosis secondary to hypovolaemic shock)
What is the risk of recurrence of placental abruption?
8%
What is vasa praevia?
Fetal blood vessels cross or run near the internal os of the cervix, in front of the presenting part. These vessels are at risk of rupture when the supporting membranes rupture, as they are unsupported by the umbilical cord or placental tissue.
What type of bleeding is the bleeding associated with vasa praevia?
Unlike placenta praevia and placental abruption, the blood loss this time is from the fetus.
What test would confirm that the blood loss is fetal and therefore possibly as a result of vasa praevia?
Kleihauer test - this must only be done if the CTG is normal as otherwise delivery should not be delayed.
How do you manage a patient with vasa praevia?
Urgent delivery before fetus exsanguinates.
What is circumvallate placenta?
A type of placental disease in which the fetal membranes (chorion and amnion) “double back” on the fetal side around the edge of the placenta. It develops secondary to outward proliferation of the chorionic villi into the decidua.
How does circumvallate placenta affect placental function?
It doesn’t
What are the complications of circumvallate placenta?
It is associated with antepartum haemorrhage, placental abruption, premature birth, miscarriage and oligohydramnios.
What is the perinatal mortality rate of antepartum haemorrhage relative to normal pregnancy?
Double
What is placenta accreta?
Placenta accreta describes the attachment of the placenta to the myometrium, due to a defective decidua basalis. As the placenta does not properly separate during labour there is a risk of post-partum haemorrhage.
What are the risk factors for placenta accreta?
Previous cesarean section
Placenta praevia
