APH Antepartum Haemorrhage Flashcards
What is the incidence of Placenta Previa at term? What are the risk factors for it ?
1 / 200
The incidence increased
1- in women with previous CS
2- maternal smoking
3- assisted reproductive technology
4- increased maternal age
What is the prevalence of placenta accreta?
1/ 300 - 1 / 2000
What is the chance of placental migration if diagnosed at 20 w ?
90% at 32w
What is the definition of :
- placenta praevia
- low lying placenta?
🚩placenta praevia: placenta lies directly over the internal os
🚩 low lying placenta: at > 16 w
placental edge is less than 20 mm from the internal os on TAS or TVS
At what gestation should we screen for placenta praevia, and when to follow up?
*At anomaly scan
*Follow up: TVS is recommended at
32 w to diagnose persistent low lying placenta
* further TVS at 36 w in women remain asymptomatic
What is the role & what are the risks of TVS in low lying placenta?
Is superior to TAS & is safe
Helpful for :
1-placenta localization Especially:for posterior placentas
2- To measure the cervical length
What is the role of measuring cervical length in the management decisions for women with placenta praevia?
A short cervical length( < 25 mm) on TVS before 34 w:
increases the risk of preterm emergency delivery & massive haemorrhage at CS
Where should women with low lying placenta be cared for in 3rd trimester, if she had recurrent bleeding?
Depends on women’s circumstances
( distance from the hospital, hb,..)
* if she was admitted to hospital: assess the risk factors for venous thromboembolism & balance the risk against the risk of bleeding
* if she was treated at home : should attend to the hospital immediately if : any bleeding or pain or contractions
Is there a place for cervical cerclage in women with low lying placenta?
IS NOT RECOMMENDED
At what gestation should women with placenta praevia be offered antenatal steroids?
SINGLE dose is recommended between 34 - 35 w
& delivery 1 w after
& prior to 34 in women with high risk of preterm delivery
Is there a place for tocolytics in women with symptomatic placenta praevia?
Maybe considered for 48h to administer antenatal steroids
At what gestation should planned delivery occur in women with low lying placenta?
- Uncomplicated placenta praevia:
36 - 37 w - history of vaginal bleeding or
High risk of preterm delivery
Late preterm delivery 34 - 36 w
What anaesthetic procedure is most appropriate for women having CS for placenta praevia?
Regional anesthesia
Is considered safe & associated with lower risk of haemorrhage than general anaesthesia
What blood products should be available in the delivery of women with placenta praevia?
1- rapid infusion & fluid warming devices should be available
2- cell salvage for women who decline blood products
⚠️ the decision to transfuse should be made on individual basis EVEN if preoperative hb < 70
What surgical approach should be used for women with placenta praevia?
1- consider vertical skin and / or uterine if the fetus is transverse lie particularly below 28w
2- consider preoperative & intraoperative US
3- if the placenta is transected during uterine incision 👉 immediately clamp the umbilical cord after fetal delivery
4- to control the haemorrhage:
- pharmacology
- intrauterine tamponade
- radiological techniques
- early hysterectomy
If placenta praevia is detected in 32 w , what is the percentage of it will resolve by term ?
50 %
How many of placentas diagnosed as low lying at routine anomaly scan TVS will reclassify them?
26 - 60 % of them
Compare CS for placenta praevia with CS for other indications, regarding risk of massive haemorrhage/ the need for blood transfusion?
The risk of massive haemorrhage is approximately 12 times more likely in CS for placenta praevia
What is the success rate in controlling PPH for Intrauterine balloon tamponade in women with placenta praevia ?
75 - 88%
What are the surgical procedures should be used for women with placenta praevia to reduce blood loss & the risk of PPH?
1- J shaped uterine incision for anterior placentas instead of cutting through the placenta
2- intrauterine balloon tamponade
( Bakri balloon, BT cath ) 400ml / warm saline
3- endouterine sutures ( B-lynch)
4- radiological techniques: transarterial embolization of internal iliac artery
What is the incidence of placenta praevia after CS?
4,5 for one CS
7,4 for 2 CS
6,5 for 3 CS
44,9 for 4 CS or more
according to 2014 studies:
10 / 1000 with 1 CS
28 / 1000 with 3 CS or more
What is the prevalence of malpositions of the fetus occurring with placenta praevia?
35 % of cases the fetus is malpositioned ( transverse/ breech)
What is the definition of placenta accreta ?
A spectrum disorder ranging from abnormally adherent to deeply invasive tissue
If the woman with placenta praevia is asymptomatic & wish for vaginal birth, how to make a decision?
By TVS
If the placental edge less than 20 mm from the internal os in the 3rd trimester OR
placental edge is thicker than 10 mm
👉 CS