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

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

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

6. Placenta Previa: Obstetric Management u If possible, delay delivery until fetus is mature u 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 u Evaluation on arrival: –airway –volume status –large bore IV access –type and cross –HCT u 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 u Large bore IV(s) u Low threshold for type and cross / blood in room u If active hemorrhage, GA, RSI, ketamine (0.5-1.0 mg/kg) or etomidate (0.3 mg/kg), succinylcholine u Maintenance: 50/50 nitrous oxide and oxygen (may omit nitrous if severe fetal distress) + low concentration inhalational agent if tolerated u After delivery: pitocin and  or omit halogenated agent;  nitrous oxide, add opioid u Be alert for placenta accreta, massive blood loss, C-hyst u May require invasive monitoring (aline, CVP)

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

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

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

12. Placental Abruption: Obstetric Management u 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 u Be alert for possibility of coagulopathy and/or hypovolemia before considering regional anesthesia u 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 u 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 u 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 u Diagnostic features: –vaginal bleeding –hypotension –cessation of labor –fetal distress –pain present in only 10% –postpartum hemorrhage may be a sign u Treatment: uterine repair, arterial ligation, hysterectomy (may be preferred)

16. Comparison of Presentation of Abruption v. Previa v. Rupture abruptionpreviarupture abd. painpresentabsentvariable vag. bloodoldfreshfresh DICcommonrarerare acute fetalcommonrarecommon distress

17. Vasa Previa u “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.” u ROM may cause fetal exsanguination. u High fetal mortality (50-75%) u Risk factor: multiple gestation (esp., triplets)

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

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

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

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

22. Uterine Atony: Ergot Derivatives u 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 u  myometrial intracellular free Ca ++, enhance action of other oxytocics u Side effects: fever, nausea/vomiting, diarrhea u 15-methyl PG F 2  (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 u Vaginal: associated with forceps, vacuum, prolonged 2nd stage, multiple gestation, PIH –Rx: I & D and packing u Vulvar: bleeding from branches of pudendal arteries u 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 u Obstetric management: –manual removal, oxytocin u 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 u Definitions: –accreta vera: adherence of placenta to myometrium –increta: invasion of placenta into myometrium –percreta: invasion of placenta to/thru the serosa u Risk factors: –prior uterine trauma + placenta previa

27. Placenta Accreta II u Placenta previa + prior C/S v. accreta risk: Number of prior C/S Incidence of accreta 05% 124% 247% 340% 467% u Rx: uterine curettage, oversewing of plac. bed, usually hysterectomy (accreta is most common indication for C-hyst)

28. Uterine Inversion u Low mortality u Risk factors: –uterine atony –inappropriate fundal pressure –unbilical cord traction –uterine anomaly u 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 u Uterine arteries are branches of internal iliacs (major supply to uterus) u Ovarian arteries also contribute during preg. u 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)