Transcript Placenta previa

If you are a doctor

In the midnight, awakens
to find that they have to
sleep in a pool of blood
You
 How to diagnosis？
 How to management？
Antepartum Hemorrhage
Obstetrics & Gynecology Hospital of Fudan University
Xu Huan
Rationale (why we care…)
• 4-5% of pregnancies complicated by 3rd trimester
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bleeding
Immediate evaluation needed
Significant threat to mother & fetus
(consider physiologic increase in uterine blood flow)
Consider causes of maternal & fetal death
Priorities in management (triage!)
Objectives
 We will be able to:
• Describe the approach to the patient with thirdtrimester bleeding
• Compare symptoms, physical findings, and
diagnostic methods that differentiate bleeding
etiologies
• Describe management and delivery options for 3rd
trimester bleeding etiologies
• Describe potential maternal and fetal morbidity &
mortality
• Describe management of postpartum hemorrhage
• Apply knowledge in the discussion of clinical case
scenarios
Vaginal Bleeding: Differential diagnosis
• Common:
• Abruption, previa, preterm labor, labor
• Less common:
• Uterine rupture, fetal vessel rupture,
lacerations/lesions, cervical ectropion, polyps,
vasa previa, bleeding disorders
• Unknown
• NOT vaginal bleeding!!!
(happens more than you think!)
Other Etiologies
• Cervicitis
• infection
• Cervical erosion
• Trauma
• Cervical cancer
• Foreign body
• Bloody show/labor
Perinatal mortality and morbidity
• Previa
• Decreased mortality from 30% to 1% over last 60
years
• Now emergent cesarean delivery often possible
• Risk of preterm delivery
• Abruption
• Perinatal mortality rate 35%
• Accounts for 15% of 3rd trimester stillbirths
• Risk of preterm delivery
• Most common cause of DIC in pregnancy
• Massive hemorrhage --> risk of ARF, Sheehan’s, etc.
Placenta previa
Definition
 After 28 pregnant weeks placental implantation over
the cervical os or in the lower uterine segment
 It constitutes an obstruction of descent of the
presenting part
 Main cause of obstetrical hemorrhage(20%)
 Incidence
0.24%-1.57% (our country).
Risk factors & Associations
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Prior cesarean delivery/myomectomy
Prior previa (4-8% recurrence risk)
Previous abortion
Increased parity
Multiple pregnancy
Advanced maternal age
Abnormal presentation
Smoking
Etiology
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Causes
Endometrial abnormality
Scared or poorly vascularized endometrium in the
corpus.
Curettage, Delivery, CS and infection of
endometrium
Placental abnormality
Large placenta (multiple pregnancy), succenturiate
lobe
Delayed development of trophoblast
Classification
Marginal
placenta previa
Partrial
Complete
placenta previa
placenta previa
Manifestation(1) Symptoms
• Painless vaginal bleeding (70%)
• Spontaneous,After coitus
• The most characteristic symptom
• late pregnancy (after the 28th week) and delivery
• Characteristics: sudden, painless and profuse
• Contractions
• No symptoms
• Routine ultrasound finding
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The mean gestational age of first bleed: 30 wks
1/3 before 30 weeks
Manifestation(2)
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Anemia or shock
repeated bleeding→ anemia
heavy bleeding→ shock
Abnormal fetal position
a high presenting part
breech presentation (often)
Physical Findings
• Bleeding on speculum exam
• Cervical dilation
• Bleeding a sx related to PTL/normal labor
• Abnormal position/lie
• Non-reassuring fetal status
• If significant bleeding:
• Tachycardia
• Postural hypertension
• Shock
Diagnosis(1)
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History
Painless hemorrhage
At late pregnancy or delivery
History of curettage or CS
Diagnosis(1)
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Signs
Abdominal findings
Uterus is soft, relaxed and nontender.
Contraction may be palpated.
A high presenting part can’t be pressed into the
pelvic inlet. Breech presentation
Fetal heart tones maybe disappear (shock or
abruption)
Diagnosis
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Speculum examination
Rule out local causes of bleeding, such as cervical
erosion or polyp or cancer.
Limited vaginal examination (seldom used)
Palpation of the vaginal fornices to learn if there is
an intervening bogginess between the fornix and
presenting part.
Rectal examination is useless and dangerous
Limited vaginal examination
Diagnosis(1)
• Ultrasound
• abdominal 95% accurate to detect
• transvaginal (TVUS) will detect almost all
• consider what placental location a TVUS may
find that was missed on abdominal
• MRI
• Check the placenta and membrane after delivery
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remember: no digital exams unless previa RULED
OUT!
Diagnosis
 Before 20 weeks’ gestation,4-6% have some degree
of placenta previa on ultrasonic examination
 90% of these resolving by the third trimester
 Only 10% of complete placenta
Differential Diagnosis
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Placental abruption
vagina bleeding with pain, tenderness of uterus.
vasa previa
In cases of velamentous cord insertion fetal vessels
cover cervical os
Abnormality of cervix
cervical erosion or polyp or cancer
vasa previa
Effects
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obstetrical hemorrhage
Placenta accreta, increta, and percreta
Anemia and infection
Premature labor or fetal death or fetal distress
Treatments
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Expectant therapy
Rest: keep the bed
Controlling the contraction: MgSO4
Treatment of anemia
Preventing infection
Treatments
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Termination of pregnancy
CS
total placenta previa (36th week), Partial placenta
previa (37th week) and heavy bleeding with shock
Preventing postpartum hemorrhage: pitocin and PG
Hysterectomy: Placenta accreta or uncontroled
bleeding
Treatments
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Vaginal delivery
Marginal placenta previa
Vaginal bleeding is limited
Management
• Initial evaluation/diagnosis
• Observe/admit to L&D
• IV access, routine (maybe serial) labs
• Continuous electronic fetal monitoring
• Continuous at least initally
• May re-evaluate later if stable, no further bleeding
• Delivery???
Management
• Less than 36 wks gestation - expectant management
if stable, reassuring
• Bed rest (negotiable)
• No vaginal exams (not negotiable)
• Steroids for lung maturation (<32 wks)
• Possible mgmt at home after 1st bleed
 70%
will have recurrent vaginal bleeding before
36 completed weeks requiring emergent cesarean
Management
• 36+ weeks gestation
• Cesarean delivery if positive fetal lung maturity by
amniocentesis
• Delivery vs expectant mgmt if fetal lung immaturity
• Schedule cesarean delivery at 37 weeks
• Discussion/counseling regarding cesarean hysterectomy
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Note: given stable maternal and reassuring fetal status, none
of these management guidelines are absolute (this is why
Obstetrics is so much fun!)
Other Considerations
• Placenta accreta, increta, percreta
• Cesarean delivery may be necessary
• History of uterine surgery increases risk
• Must consider these diagnoses if previa present
• Could require further evaluation, imaging (MRI
considered now)
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NOT the delivery you want to do at 2 am
A
B
Abnormally adherent placentation. A. Placenta
accreta. B. Placenta increta. C. Placenta percreta
C
Cesarean hysterectomy specimens with placenta percreta.
Cesarean hysterectomy specimens with placenta percreta.
Placental abruption
Definition
• abruptio placentae or placental abruption:
placental separation from its implantation site
before delivery (the normally implanted
placenta )
• Incidence
• complicates 0.5-1.5% of all pregnancies
• recurrence risk
• 10% after 1st episode
• 25% after 2nd episode
Risk factors & Associations
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Cocaine
maternal hypertension
abdominal trauma
smoking
prior abruption
preeclampsia
multiple gestation
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prolonged PROM
uterine decompression
short umbilical cord
chorioamnionitis
multiparity
Pathology
 Placental separation is initiated by hemorrhage
into the decidua basalis with formation of a
decidual hematoma
 Concealed hemorrhage
 Revealed hemorrhage
revealed hemorrhage
concealed hemorrhage
Total placental abruption with concealed hemorrhage and fetal death
Maternal-fetal risk
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perinatal mortality: 35%
DIC
hypovolemic shock
acute renal failure
Sheehan’s syndrome
Symptoms
• Vaginal bleeding
• Abdominal or back pain
• Uterine contractions
• Uterine tenderness
Physical Findings
• Vaginal bleeding
• Uterine contractions
• Hypertonus
• Tetanic contractions
• Non-reassuring fetal status or demise
• Can be concealed hemorrhage
Laboratory Findings
• Anemia
• may be out of proportion to observed blood
loss
• DIC
• Can occur in up to 10% (30% if “severe”)
• First, increase in fibrin split products
• Followed by decrease in fibrinogen
Diagnosis
• Clinical scenario
• Physical exam
• Not digital pelvic exams until rule out previa
• Careful speculum exam
• Ultrasound
• Can evaluate previa
• Not accurate to diagnose abruption
Management
• Physical exam
• Continuous electronic fetal monitoring
• Ultrasound
• Assess viability, gestational age, previa, fetal
position/lie
• Expectant management
• vaginal vs cesarean delivery
• Available anesthesia, OR team for stat
cesarean delivery
Partial placental abruption with adhered clot
Couvelaire Uterus