placenta previa
TRANSCRIPT
DefinitionDefinition
• The presence of placental tissue overlying or proximate to the cervical os .
Several forms of PP : Several forms of PP :
• Complete PP .
• Partial PP .
• Marginal PP
• Low – lying PP . ( within 2-3 cm os . )
Iincidence : PP Iincidence : PP • 4/1000 pregnancy over 20 weeks
Risk factors :Risk factors :_ parity ( 0/2% nullipara – 5% grand multipara _ maternal age : • 0/03 % nullipara 20 < age < 29 • 0/25 % nullipara > 40 year_ number of perior c/s : • ( incidence 10% after 4 or more ) _ number of curettage for spontaneous or induced abortion _ maternal smoking : _ residence at higher altitudes _ male fetus_ multiple gestation ( 39/1000 twin live and 2.8 previa /1000 lit) _ gestational age : early pregnancy
Pathogenesis of PP : Pathogenesis of PP :
• Endometrial scarring in the upper segment
• Initial tropnoblastic nidation or unidirectional growth into LS .
• Increased placental surface to compensate for a reduction in uteroplacental oxygen
• the length of lower uterine segment 0/5cm(20 weeks )
• 5 cm ( at term )
Clinical manifestations : Clinical manifestations : • Painless vaginal bleeding ( 70 – 80 % ) VB + uterine contraction : ( 10 – 20 % ) • Asymptomatic (ultrasound ) : ( <10 % ) Initial bleeding : typically 34 weeks • 1/3 : Bleeding prior to 30 weeks Blood
transfunsions & preterm delivery & perinatal mortality
• 1/3 : VB 30 - 36 weeks • 1/3 : VB after 36 weeks contraction - vaginal
exam - Coitus vaginal Bleeding
Associated conditions : PP Associated conditions : PP
• mal presentation
• PPROM
• IUGR : 16%
• Congenital anomaly
Differential diagnosis : Differential diagnosis :
• Third trimester bleeding 3-4% : pregnancy
• Abruptio placenta ( 31% )
• PP ( 22% )
• Other cause ( 47% ): labor
rupture
neoplasm
Ultrasonography Ultrasonography Trans vaginalTrans vaginal : gold standard _ safe _ effective
technique .• accuracy than 99% Trans labial ultrasoundTrans labial ultrasound • excellent images Trans abdominal ultrasoundTrans abdominal ultrasound • accuracy 95% • false negative rate 7%
• ** an over distended bladder for anterior previa
• ** for posterior previa : Trendelenburg position
Persistence after second trimester diagnosis : Persistence after second trimester diagnosis :
• 10 _ 20 weeks GA 4 _ 6% PP • 10 folds third trimester (0/4 % )
• Complete previa • Amount of overlap • Overlap (20 - 23 w)> 25 mm persistence 40%
• Overlap < 14 to 15 mm 20% • Repeat ultrasound: 28 w and 34 w
Exclusion of placenta accreta Exclusion of placenta accreta MRI : MRI : • Posterior previa
• High cost
• Limited availability
Antepartum management Antepartum management
• General principles :
• Sonography
• Avoidance of coitus & digital cervical examination & exercise & decrease activity
• Counseling to seek immediate medical attention if VB
Acute care of symptomatic PP : Acute care of symptomatic PP : • admit to the labor • maternal & fetal monitoring • large bore IV & crystalloid & hemodynamic
stability & adequate urine out put . • Type a cross _ match for four units packed
blood cells . (Actively bleeding HCT > 30 ) • maternal cardiac monitor: BP &PR every 15
min/h • FHR : continuously monitored . • FHR or FHR or sinusoidal : Anemia & Hypoxia
• quantitative monitoring of VB loss
• Urine output : hourly with Foley catheter
• Laboratory monitoring
• HB-HCT /q 4 -6 h
• Serum electrocytes & indexs of renal function:every 6-8 / h
• PT _ PTT _ CBC _ PLT- fibrinogen
• DIC delivery
• Unstable hemodynamic or underlying disease (cardiac& pulmonary) place swan Ganz catheter ( CVP )
• ( PCWP ) & cardiac out put
• Tocolysis is not administeral to VB If : VB or ceased
Delivery indicated . Delivery indicated . • FHR • Life threatening maternal VB • VB after 34weeks & in presence of pulmonary
maturity • C/S : choice • ND : hemodynamical stability & fetal demise &
previable fetus & some cases of marginal previa
• Anesthesia : G A for emergency Cs
• Regional A for stable patients
• RH ( D ) negative women
• RH ( D ) _ Immune globulin .
Conservation management of stable preterm patients Conservation management of stable preterm patients
• Hospitalized at bed rest , minimize constipation ( high fiber diet & stool softens ) • Periodic maternal HCT • Ferrous gluconate supplements ( 3- 4 time/day ) + vitamin
C • Maternal blood sample type, cross match ( 2 _ 4 units P.C )
HCT > 30 • Corticosteroid therapy : ( 24 _ 34 weeks ) • RH ( D ) _ immunoglobolin : ( 3 weeks ) • Fetal Heart rate monitoring : • sonography : IUGR _ AF _ placenta location • Tocolysis : contraction ( Mg so4 4 H2o ) • Cervical cercelage : longer gestations heavier birth
weight , reduction in antenatal hospitalization .
PPROM & PP : PPROM & PP :
• Tocolysis : controversial _ hemodynamically stable & uninfected women
• Corticosteroid < 32 weeks
Out patient management : Out patient management : • Restriction activity • 48 h after stopped bleeding • Live within 15 min of the hospital • Have an adult companion available 24h/day ( for transport & cell ambulance ) • Be reliable & able to maintain bed rest at home . • understand the risks of PP . • Benefits of out patients • Longer duration of pregnancy ( 33- 36 w ) higher
mean birth weight • Lower over all cost
Delivery Delivery
Timing :
• FHR
• Life threatening material hemorrhage
• After 34 weeks : presence fetal pulmonary maturity .
• Amniocentesis at 36 weeks : repeat every week .
Procedure :Procedure :• Abdominal delivery ( complete previa ) • Expect : fetal demise _ previable fetus marginal PP
placenta > 2 cm from OS • C/S : placenta within 2 cm of internal • Available 2 to 4 units PC . • Surgical instruments : CS hysterectomy • 5 - 10 % risk placenta accreta . • Pre operative sonographyic localization of placenta .• Incised placenta : delivered rapidly & cord clamped to hemorrhage from fetus .
Out come PP : Out come PP :
• General General • Maternal mortality : 1 % • perinatal mortality : 10 % • Principal causes of prenatal mortality • * Preterm delivery • *Fetal anemia• *Hypoxia • *Growth restriction • Recurrence rate :Recurrence rate : 4 _ 8 %
Pregnancy termination : Pregnancy termination : • Termination at 13 _ 24 weeks : laminaria
D&E ( blood loss )
• Associated conditions :
• Velamentous umbilical lord
• Vasa previa
• Placenta accreta
Velamenous umbilical cord : Velamenous umbilical cord : • Vessels surrounded by fetal memberan,no whartons jelly • 1% singleton • 10% multiple gestation • 25% fetal anomalies • sonography :sonography : umbilical cord insertion, 12.5 __ single
umbilical artery • Diagnosis :Diagnosis : color Doppler , flow • Obstetric complications :Obstetric complications : IUGR - Prematurity _ congenital
anomalies low APGAR scores , fetal bleeding, retained placenta .
• Cord compression by fetal descending fetal death . • Pregnancy should not be allowed to proceed beyond 40
weeks .
Vasa previa :Vasa previa :• low lying placenta previa • monochorionic twin gestations • velamentous cord insertion • multi lobed placenta • IVF • Diagnosis :Diagnosis : VB + abnormality of FHR (sinusoidal
pattern) • Ultrasound color Doppler Ultrasound color Doppler vasa previa • ___ cord movement • Termination : C/S 35- 36 weeks ( corticosteroids ) •
Placenta accreta :Placenta accreta :
• 5_ 10 % : with PP
• 25 % : PP + one P C/S
• 50 % : PP + 2 or more P C/S
Introduction : Introduction : • A.P : premature separation of a normally implanted
placenta after 20 weeks but prior to delivery infant .
Immediate cause : • Rupture of defective maternal vessels in decidua• basallis
Rare cause :• Bleeding fetal _ placenta vessels . • Separation of placenta : hematoma • Retro placenta complete partial
exchange gases nutrient to the fetus
Incidence Incidence • 0/4 to 1/3% ( 1/75 _ 1/225 )
• Incidence to be increasing • Sever AP to still birth : 1/ 830 • 1/3 antepartum bleeding ___ AP • Pathogenesis :Pathogenesis :• Catastrophic trauma • PPROM• Chronic pathologic vascular process ( IUGR _
preterm labor )
Risk factors : Risk factors : mechanical factors :mechanical factors :• Truma : external compression decompression ,
rapid acceleration _ deceleration present within 24h of event Monitoring : 4_ 6 h period ( VB _ tenderness ) Sudden internal decompression of the
uterus : PPROM • Placental implantation over uterine anomaly or
myoma Hypertension :Hypertension : server & chronic, 5 folds server
Abruption • Antihypertensive therapy dose not reduce risk
of Abruption
cigarette smoking :cigarette smoking : 2.5 fold server A.P Risk : 40% / pocket / day Mechanism : ischemic peripheral necrosis of
decidua cigarette smoker & hypertension are synergistic .
maternal age & paritymaternal age & parity 2.5 % • Endometrial scarring & impaired
decidualization cocaine abuse :cocaine abuse : 10% • Acute vasoconstriction ischemia
reflex vasodilation bleeding
PPROM :PPROM : 2 - 5 % AP • Infection or oligohydramnios 7 to 9 fold• Abruption thrombin proteas PPROM
inherited thrombophiliainherited thrombophilia : : 1/5 – 12 folds • factor V leiden: • maternal venous thromboembolism , fetal death
,IUGR , sever PIH , abruption • Prc ,Prs , Antithrombin • VII , VIII , IX , XI • Hyperhomocysteinemia : 31% Ab • Congenital hypofibrinogenemia
afibrinogenemia, XIII AP : (Heparin & folate)
Previous Abruption :Previous Abruption : • Ten folds . AP multifetal gestation & polyhydramniosmultifetal gestation & polyhydramnios • 3 folds AP • cause : rapid uterine decompression upon
delivery of one twin . others : others : • folate deficiency , leiomyoma ,
circumvallata placenta
Clinical manifestation Clinical manifestation • VB > 80% • Abdominal pain > 50% • Uterine contraction ( tachy systole ) • Uterine tenderness • FHR• Uterine tone• Back pain : posterior placenta • Preterm birth • Chronic abortion
Concealed hemorrhageConcealed hemorrhage
• 20%
• placental margins remain adherent
• The fetal membrane retain their attachment to the uterine wall
• The fetal head obstruct cervical os
Coagulopathy Coagulopathy
• server abruption with death fetus 20% coagulopathy
• hypofibringenemia
• DIC
• Kidney
• Fetus : BPP
• Utero placental insufficiency
Diagnosis :Diagnosis :• Clinic
• Sonography _ difficult
• Laboratory not useful _ CA 125, D- Dimer _ thrombo modolin -Fibrinogen 200 mg / dl-PLT
• Pathologic findings:
• Clot depression Maternal surface of placenta
Differential diagnosis :Differential diagnosis :
• Placenta previa
• Vasa previa
• Labor
• Uterine rupture
• Cervicovaginal neoplasm
• Abdominal disorder ( pain without bleeding )
Management Management • Initial approach :
• Closely monitoring
• Large _ Bore IV
• Maternal hemodynamic status:
• BP- PR-Out Put - BG Rh- HCT- PLT-Fib- PT- PTT
• Normotensive + normal HCT & Abruption :
• Previousely hypertensive & acute bleeding
• Fetal monitoring• Crystalloid infusion • RBC , packed cells • 300 cc packed cell 200 cc RBC 3-4% HCT• PT & PTT( 1/5 times): 2 units FFP • 5 units packed cell: PTT- PT - fibrinogen - PLT • PLT < 50,000 : 6 units of PLT • Tocolysis : contraindication ( sever abruption ,
DIC FHR
managementmanagement
• Delivery :Delivery : optimal treatment
• Mild Abruption : Expectant management
• Corticosteroid therapy < 34 weeks
• tocolysis < 34 weeks
Labor : Labor : • Monitoring on labor room . • Mode & timing delivery :• Condition & gestational age• Condition ( BP , DIC , Hemorrhage status of cervix , FHR ) • VD : Amniotomy _ Internal & monitoring of fetus &
intrauterine press catheter • Pressure > 25 abnormal uterine flow oxygenation of
fetus • Poor condition sever hypertone , hemorrhage ,DIC, FHR
• C/S : HCT > 25% , fibrinogen (150- 200 mg/dl ), PLT >
60,000 • Anesthesia : GA • Appropriate mode of delivery : C/S• ( VD : cervical dilation in Parous women
Out comeOut come• Perinatal mortality 20% (still birth, 50% placenta
separation) • IUGR• Prematurity : 4 folds • C/S : 3 /4 delivery ( Sweden ) • Midtrimester abruption poor prognosis • Recurrence risk : 5 _ 15 % • Base line risk : o/4% to 1/3% • Two abruption: risk 25% • Sever abruption: ( dead fetus ) 7% • Abruption & subsequent pregnancy :• Abruption • SGA • Preterm labor • PIH
Management in subsequent pregnancy Management in subsequent pregnancy
• Risk factors : Cigarette • Thromboprophylaxis : Thrombophialias • SGA • Preterm labor • Six weeks prior GA of initial abruption • Elective C/S 39 to 40 • recurrent abruption & fetal death • Preterm Delivery after lung maturition