Peripartum Hemorrhage

1. Peripartum Hemorrhage Anita M. Backus, M.D. Associate Clinical Professor, UCLA School of Medicine Director of Obstetric Anesthesia, UCLA Medical Center

2. Peripartum Hemorrhage • Causes of maternal death in US, 1987-90 (9.1/100,000) • hemorrhage: 28.7% (*) • embolism: 19.7% (*) • pregnancy-induced hypertension: 17.6% (*) • infection: 13.1% (*) • cardiomyopathy: 5.6% (*) • anesthesia: 2.5% (*) * compared with 1979-86

3. Antepartum Hemorrhage • 4% of women may develop antepartum hemorrhage. • Causes: • placenta previa (1/200) • placental abruption (1/100) • uterine rupture (<1% in scarred uterus) • vasa previa (1/2000-3000)

4. Placenta Previa • Definitions: • Total: covers the cervical os • Partial: covers part of the os • Marginal: lies close to, but does not cover, the os • Risk factors: • multiparity • advanced maternal age • prior C/S or other uterine surgery • prior placenta previa

5. Placenta Previa: Diagnosis • Painless vaginal bleeding in 2nd/3rd trimester • Confirmed by ultrasound • Vaginal exams are avoided • Up to 10% may have simultaneous abruption • Maternal shock is uncommon with 1st presentation of bleeding

6. Placenta Previa: Obstetric Management • If possible, delay delivery until fetus is mature • Indications for delivery: • active labor • documented fetal lung maturity •  37 weeks gestational age • excessive bleeding • development of another obstetric complication mandating delivery

7. Placenta Previa:Anesthetic Management • Evaluation on arrival: • airway • volume status • large bore IV access • type and cross • HCT • Patient has  bleeding risk during surgery • OB may have to cut into placenta to remove baby • lower uterine implantation site does not contract as well as normal fundal site •  risk of placenta accreta (esp. if prior C/S)

8. Placenta Previa:Anesthetic Management II • Large bore IV(s) • Low threshold for type and cross / blood in room • If active hemorrhage, GA, RSI, ketamine (0.5-1.0 mg/kg) or etomidate (0.3 mg/kg), succinylcholine • Maintenance: 50/50 nitrous oxide and oxygen (may omit nitrous if severe fetal distress) + low concentration inhalational agent if tolerated • After delivery: pitocin and  or omit halogenated agent;  nitrous oxide, add opioid • Be alert for placenta accreta, massive blood loss, C-hyst • May require invasive monitoring (aline, CVP)

9. Placenta Previa:Anesthetic Management III • Elective, not in labor • regional anesthesia (spinal vs. epidural) preferred • In labor, not hemorrhaging • regional anesthesia preferred • Importance of history of prior C/S’s

10. Placental Abruption • Premature separation of placenta from endometrium • Diagnosis: vaginal bleeding, uterine tenderness,  uterine tone • Risk factors: • HTN – multiparity • AMA – smoking • PROM – cocaine • trauma – h/o abruption

11. Placental Abruption II • Complications • shock • acute renal failure • DIC (coagulopathy in 10% of these pts.) • fetal distress/demise • “Hidden” blood loss may approach 2500 cc

12. Placental Abruption:Obstetric Management • Depends on fetal maturity, size of abruption, presence of fetal distress • continuation of pregnancy • induction/augmentation of labor • Cesarean section

13. Placental Abruption:Anesthetic Management • Be alert for possibility of coagulopathy and/or hypovolemia before considering regional anesthesia • For stat C/S, GA most appropriate if known or suspected hypovolemia or DIC • ketamine (or etomidate) • volume resuscitation •  invasive monitoring

14. Uterine Rupture vs. Dehiscence • Uterine scar dehiscence: • fetal membranes remain intact, fetus is not extruded intraperitoneally, separation limited to old scar, peritoneum overlying is intact • usually no fetal distress / mat. hemorrhage • Uterine rupture: • separation of scar  extension, rupture of fetal membranes with extrusion • results in fetal distress / mat. hemorrhage • fetal mortality = 35%

15. Uterine Rupture II • Diagnostic features: • vaginal bleeding • hypotension • cessation of labor • fetal distress • pain present in only 10% • postpartumhemorrhage may be a sign • Treatment: uterine repair, arterial ligation, hysterectomy (may be preferred)

16. Comparison of Presentation of Abruption v. Previa v. Rupture abruption previa rupture abd. pain present absent variable vag. blood old fresh fresh DIC common rare rare acute fetal common rare common distress

17. Vasa Previa • “Umbilical vessels separate in the membranes at a distance from the placental margin and some of the vessels (fetal) cross the internal os and occupy a position ahead of the presenting part of the fetus.” • ROM may cause fetal exsanguination. • High fetal mortality (50-75%) • Risk factor: multiple gestation (esp., triplets)

18. Vasa Previa II • Diagnosis • moderate vag bleeding + fetal distress • vessels may be palpable thru dilated cervix • vessels may be visible on ultrasound • Difficult to distinguish clinically from abruption • Can look for fetal Hb (Kleihauer-Betke test) or nucleated RBC’s in shed blood • Rx: C/S, resuscitation of infant (volume)

19. Postpartum Hemorrhage • EBL > 500 cc • 10% of deliveries • If within 24 hrs. pp = 1 pp hemorrhage • If 24 hrs. - 6 wks. pp = 2 pp hemorrhage • Causes • uterine atony – genital trauma • retained placenta – placenta accreta • uterine inversion

20. Uterine Atony • Most common cause of pp hemorrhage • Contraction of uterus is 1 mechanism for controlling blood loss at delivery • oxytocin and prostaglandins • Risk factors • multiple gestation – chorioamnionitis • macrosomia – precipitous labor • polyhydramnios – tocolytics • high parity – halogenated agents • prolonged labor

21. Uterine Atony: Treatment • uterine massage • oxytocin: • produced by posterior pituitary • causes peripheral vasodilation, reflex tachycardia • administered diluted in IV fluid, not IV push • metabolized/excreted by liver, kidney, oxytocinase • ergot derivatives • prostaglandins • If drugs fail, embolization of arterial supply, ligation, or hysterectomy

22. Uterine Atony:Ergot Derivatives • ergonovine and methylergonovine (methergine) • act via -adrenergic mechanism • adverse effects: nausea/vomiting, vasoconstriction (including coronary), HTN, PAP • relative contraindications: chronic HTN, PIH, PVD, CAD • dose: 0.2 mg IM (not IV), last 2-3 hrs.

23. Uterine Atony:Prostaglandins •  myometrial intracellular free Ca++, enhance action of other oxytocics • Side effects: fever, nausea/vomiting, diarrhea • 15-methyl PG F2 (Carboprost, Hemabate) • may cause bronchospasm, altered VQ,  shunt, hypoxemia, HTN • 250 g IM or intramyometrially q 15-30 min, up to max 2 mg. • contraindications: asthma, hypoxemia

24. Genital Trauma • Vaginal: associated with forceps, vacuum, prolonged 2nd stage, multiple gestation, PIH • Rx: I & D and packing • Vulvar: bleeding from branches of pudendal arteries • Retroperitoneal: least common, most dangerous • laceration of branch of hypogastric during C/S (or uterine rupture) • Dx: CT • Rx: expl. lap., ligation of hypogastric, hyst

25. Retained Placenta • Obstetric management: • manual removal, oxytocin • Anesthetic management: • epidural or spinal anesthesia, if not hypovolemic • or MAC • or GA (ketamine, RSI, intubate, 50% nitrous, fentanyl) • Uterine relaxation may be requested (NTG)

26. Placenta Accreta • Definitions: • accreta vera: adherence of placenta to myometrium • increta: invasion of placenta into myometrium • percreta: invasion of placenta to/thru the serosa • Risk factors: • prior uterine trauma + placenta previa

27. Placenta Accreta II • Placenta previa + prior C/S v. accreta risk: Number of prior C/S Incidence of accreta 0 5% 1 24% 2 47% 3 40% 4 67% • Rx: uterine curettage, oversewing of plac. bed, usually hysterectomy (accreta is most common indication for C-hyst)

28. Uterine Inversion • Low mortality • Risk factors: • uterine atony • inappropriate fundal pressure • unbilical cord traction • uterine anomaly • Rx: replace the uterus, oxytocin, Hemabate, methergine • may need uterine relaxation transiently • NTG(50-100 g IV)vs. halogenated agent • anecdotal reports of other nitrates, terb, Mg

29. Invasive Treatment Options for Obstetric Hemorrhage • Uterine arteries are branches of internal iliacs (major supply to uterus) • Ovarian arteries also contribute during preg. • Options • angiographic embolization • bil. surgical ligation of uterine, ovarian, internal iliacs (preserves fertility): 42% success • Cesarean or pp hysterectomy • EBL 2500 cc (emergent), 1300 cc (elective)