Amniotic Fluid Embolism

1. Amniotic Fluid Embolism Women’s Hospital School of Medicine Zhejiang University Wang Zhengping

2. Definition Amniotic Fluid Embolism is a complex disorder during labor characterized by amniotic fluid entering into the maternal circulation which causes acute pulmonary embolism, shock, DIC, acute renal failure or abrupt death.

3. overview • An devastating complication during labor • Mortality: up to 60%~80% • May occur in the first and second trimester abortions • Recently, it is also termed “anaphylactoid syndrome of pregnancy”

4. Why amniotic fluid can enter into the maternal circulation?

5. Etiology :Three factors • There is a breach in vein or blood sinus at the trauma site of cervix and the body of uterine • Higher pressure of amniotic cavity • Disruption of fetal membrane amniotic fluid enters into the maternal circulation through the breached vein and blood sinus

6. What would happen after the amniotic fluid enter into the maternal circulation

7. pathophysiology • Pulmonary artery hypertension • Allergic shock • DIC • Acute renal failure(ARF) Amniotic fluid→inferior vena → atrio dextro → right ventricle →pulmonary artery

8. Clinical presentation Acute amniotic fluid embolism: occur acutely Pulmonary artery hypertension/Shock Hemorrhage due to DIC Acute renal failure Typical: Bulk colporrhagia shock Atypical: (occur mainly after delivery)

9. Diagnosis • According to the typical clinic manifestation, we can make the preliminary diagnosis and save the patients immediately • While saving the patients do the necessary auxiliary examination, including: a. Collecting blood from arteria pulmonalis and inferior vena, and finding components of amniotic fluid b. The basis of laboratory examination for DIC c. ECG d. X-ray e. Autopsy

10. Basis of laboratory examination for DIC • PLT＜ 100 ╳109/L or it was gradually decrease • fibrinogen <1.5g/L • PT >15 s • plasm protamine paracoagulation test (+) • Obtrite RBC in blood smear

11. Management • Improve hypoxia • Anti-anaphylacic shock • Prevent DIC and acute renal failure(ARF) • Prevent infection

12. Treatment 1、Disengage pulmonary hypertension, improve hypoxia: Oxygenation Aminophylline Narceine Atropine phentolamine Anticonvulsive drug

13. 2、Anti-anaphylacic Treatment • Glucocorticosteroid Hydrocortisone Dexamethasone

14. 3、Anti-shock Treatment • Transfusion • Angiotensin • Treat heart failure • Cure acidemia

15. 4、Prevent and cure DIC Treatment • Use decoagulant and heparin as early as possible?

16. Prevent ARF: aware of urinary volume Furosemide Prevent infection using antibiotic drug with low toxicity 5、Prevent or cure ARF and infection Treatment

17. Treatment 6、Obstetric management post partum intrapartum antepartum amnionic fluid embolism drug treatment Cervical apertura is not open or not fully open Cervical apertura is fully dilatting Without postpartum hemorrhage cesarean section delivery Forcep delivery Without hemorrage postpartum hemorrhage Go on the expectant treatment Go on the expectant treatment uterectomy

18. Prevention • Artificial rupture of membrane without stripping of membrane • Don’t conduct artificial rupture of membrane when uterine is constricting • Master the indication of oxytocin application • Protect the vessel during the caesarean section • Avoid precipitate labor, birth trauma, rupture of uterus, cervical laceration • Aware of the predisposing factor

19. Thanks