_previa前置胎盘课件

If you are a doctor nIn the midnight, the pregnant women awakens to find that they have to sleep in a pool of blood How to diagnosis？ How to management？ You Antepartum Hemorrhage Obstetrics & Gynecology Hospital of Fudan University Xu Huan Rationale (why we care) 4-5% of pregnancies complicated by 3rd trimester 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 third- trimester 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 acute renal failure, Sheehans, 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 Prior cesarean delivery/myomectomy Prior previa (4-8% recurrence risk) Previous abortion Increased parity Multiple pregnancy Advanced maternal age Abnormal presentation Smoking Etiology Causes 1.Endometrial abnormality 1)Scared or poorly vascularized endometrium in the corpus. 2)Curettage, Delivery, CS and infection of endometrium 2.Placental abnormality Large placenta (multiple pregnancy), succenturiate lobe 3.Delayed development of trophoblast Classification Complete placenta previa Partrial placenta previa Marginal placenta previa Classification Symptoms(1) 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 vThe mean gestational age of first bleed: 30 wks v1/3 before 30 weeks Symptoms(2) 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 Abnormal position/lie Non-reassuring fetal status If significant bleeding: Tachycardia Postural hypertension Shock Diagnosis(1) History 1.Painless hemorrhage 2.At late pregnancy or delivery 3.History of curettage or CS Diagnosis(2) Signs 1.Abdominal findings 1)Uterus is soft, relaxed and nontender. 2)Contraction may be palpated. 3)A high presenting part cant be pressed into the pelvic inlet. (Breech presentation) 4)Fetal heart tones maybe disappear (shock or abruption) Diagnosis(3) 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(4) 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 vremember: no digital exams unless previa RULED OUT! Diagnosis(5) 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 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 Velamentous placenta vasa previa Effects obstetrical hemorrhage Placenta accreta, increta, and percreta Anemia and infection Premature labor or fetal death or fetal distress Abnormally adherent placentation. A. Placenta accreta. B. Placenta increta. C. Placenta percreta A B C Management(1) Less than 36 wks gestation - expectant management if stable, reassuring Rest: keep the bed No vaginal exams (not negotiable) Steroids for lung maturation (32 wks) Controlling the contraction: MgSO4 Treatment of anemia Preventing infection v70% will have recurrent vaginal bleeding before 36 completed weeks requiring emergent cesarean Management(2) Initial evaluation/diagnosis Observe/admit to Labor & Delivery Intravenous access, routine (maybe serial) labs Continuous electronic fetal monitoring Continuous at least initally May re-evaluate later if stable, no further bleeding Delivery? Management Termination of pregnancy 1.CS 1)total placenta previa (36th week), Partial placenta previa (37th week) and heavy bleeding with shock 2)Preventing postpartum hemorrhage: pitocin and PG 3)Hysterectomy: Placenta accreta or uncontroled bleeding Cesarean hysterectomy specimens with placenta percreta. Cesarean hysterectomy specimens with placenta percreta. (Lateral fundal percreta caused hemoperitoneum in late pregnancy ) Management 36+ weeks gestation Cesarean delivery if positive fetal lung maturity by amniocentesis Delivery vs expectant management if fetal lung immaturity Schedule cesarean delivery at 37 weeks Discussion/counseling regarding cesarean hysterectomy vNote: 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) vNOT the delivery you want to do at 2 am Management 2.Vaginal delivery Marginal placenta previa (2cm) Vaginal bleeding is limited 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 Cocaine maternal hypertension abdominal trauma smoking prior abruption preeclampsia multiple gestation 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 hemorrhageconcealed hemorrhagemixed hemorrhage Total placental abruption with concealed hemorrhage and fetal death Maternal-fetal risk perinatal mortality: 35% DIC hypovolemic shock acute renal failure Sheehans 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 Foll