Amniotic Fluid Embolism

Women’s Hospital School of Medicine Zhejiang University

Wang Zhengping

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.

overview

An devastating complication during labor Mortality: up to 60%~80% May occur in the first and second trimester aborti

ons Recently, it is also termed “anaphylactoid syndro

me of pregnancy”

Why amniotic fluid can enter into the maternal circulation?

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

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

pathophysiology

Pulmonary artery hypertension Allergic shock DIC Acute renal failure(ARF)

Amniotic fluid→inferior vena → atrio dextro → right ventricle →pulmonary artery

Clinical presentation

Acute amniotic fluid embolism: occur acutely

Pulmonary artery

hypertension/ Shock

Hemorrhage due to DIC

Acute renal failure

Typical: three phages

Atypical: Bulk colporrhagia

shock(occur mainly after delivery)

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 fluidb. The basis of laboratory examination for DICc. ECGd. X-raye. Autopsy

Basis of laboratory examination for DIC

PLT ＜ 100 10╳ 9/L or it was gradually decrease fibrinogen <1.5g/L PT >15 s plasm protamine paracoagulation test (+) Obtrite RBC in blood smear

Management

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

Treatment

Anticonvulsive drug

OxygenationAminophylline

Narceine

Atropine

phentolamine

1 、 Disengage pulmonary hypertension, improve hypoxia:

2 、 Anti-anaphylacic

Glucocorticosteroid

Treatment

Hydrocortisone

Dexamethasone

3 、 Anti-shock

Transfusion Angiotensin Treat heart failure Cure acidemia

Treatment

4 、 Prevent and cure DIC

Use decoagulant and heparin as early as possible

Treatment

5 、 Prevent or cure ARF and infection

Prevent ARF:• aware of urinary vol

ume• Furosemide

Prevent infection• using antibiotic drug

with low toxicity

Treatment

antepartum intrapartum post partum

amnionic fluid embolism

drug treatment

Forcep delivery

postpartum hemorrhage

uterectomy

Without postpartum hemorrhage

Go on the expectant treatment

cesarean section delivery

Without hemorrage

Go on the expectant treatment

Treatment 6 、 Obstetric management

Cervical apertura is not open or not fully open

Cervical apertura is fully dilatting

Artificial rupture of membrane without stripping of membrane Don’t conduct artificial rupture of membrane when uterine is c

onstricting Master the indication of oxytocin application Protect the vessel during the caesarean section Avoid precipitate labor, birth trauma, rupture of uterus, cervic

al laceration Aware of the predisposing factor

Prevention