Placental Issues Flashcards
What is placenta praevia?
Placenta lies over internal cervical os
What is a “low-lying placenta”?
Placenta low in uterus but does not cover the internal os
What is the most important risk factor for placenta praevia?
Previous C sec
Give other risk factors for placenta praevia
High parity >40 years Multiple preg Prev PP Uterine inferion
How does placenta praevia classically present?
Painless vaginal bleeding after week 24
What is placental abruption?
Some/all of placenta separates from the uterine wall
What is vasa praevia?
Foetal blood vessels run near the internal cervical os
What is the triad of symptoms in vasa praevia?
vaginal bleeding
membrane rupture
foetal compromise
What is uterine rupture?
Full thickness disruption of the uterine muscle and overlying serosa
What are the major risk factors for uterine rupture?
Prev C sec Uterine surgery (eg myomectomy)
Which infections may predispose to placenta praevia?
Candida
BV
Chlamydia
Which local problems may predispose to placenta praevia?
Polyps
Cervical ectropion
Carcinoma
Which test can be performed to determine req’d dose of anti-D?
Kleihauer test
What is HELLP syndrome characterised by?
Haemolysis
Elevated Liver enzymes
Low Platelet count
What is HELLP syndrome?
Variant of pre-eclampsia
What is the main investigation of placenta praevia?
USS
What extra investigation should be performed in women >26 weeks gestation with placenta praevia?
CTG
How is should a low lying placenta discovered at 24 weeks be managed?
Repeat scan at 36 weeks (as is likely it will sort itself)
How should placenta praevia discovered at 24 weeks be managed?
Repeat scan at 32 weeks
How should placenta praevia present at 32 weeks be managed?
Delivery by C sec at 38 weeks
Within how long of bleeding is anti-D given?
72 hours
Which examination should not be performed with placenta praevia?
Digital vaginal
Speculum
Outline the pathophysiology of placental abruption
Rupture of maternal vessels at basal layer of endometrium
Bleeds and splits placenta form basal layer
What are the two main types of placental abruption?
Revealed
Concealed
Describe a revealed placental abruption?
Bleeds down the side of the placental separation and drains through the cervix
Describe a concealed placental abruption
Bleed remains in uterus and forms a retroplacental clot
May causes systemic shock
What are the main risk factors for placental abruption?
Prev PA Pre-eclampsia Abnormal lie Polyhydramnios Abdo trauma Drug use/smoking
How does placental abruption present classically?
Sudden onset extreme pain and bleedign
How does the uterus feel on examination of placental abruption?
Painful
“Woody” (tense)
USS can be used to rule in or out placental abruption true/false
False
Good for ruling in but poor for ruling out
How is placental abruption managed?
Induction of labour/emergency delivery
When in emergency delivery by C-sec offered in placental abruption?
Maternal or foetal compromise
When would induction of labour be offered in placental abruption
No foetal or maternal compromise
