0071643192.pdf

OBSTETRICS AND GYNECOLOGY

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■ “Mini-RhoGAM” (50 μg) can be used for patients <13 weeks gestation.

■ Give within 72 hours of exposure.

■ If the volume of fetal blood to which the mother has been exposed may

be large, the Kliehauer-Betke testcan be used to quantify fetomaternal

transmission.

THIRD TRIMESTER BLEEDING

Placental Abruption

Placental abruption is premature separation of the implanted placenta from

the uterine wall. It occurs in 1–2% of all pregnancies. Bleeding between the

placenta and uterine wall can result in significant blood loss with maternal

and fetal compromise. Separations >50% result in fetal death.

Risk factors for abruption include:

■ HTN

■ Advanced maternal age

■ Multiparity

■ Smoking

■ Cocaine use

■ Previous abruption and abdominal trauma

SYMPTOMS

■ Vaginal bleeding

■ Abdominal pain

EXAM

■ Uterine tenderness

■ Uterine irritability with hypertonic/hyperactive contractions.

■ Fetal distress and maternal DIC may occur.

■ An obstetrician should be consulted prior to pelvic examination in the set-

ting of third trimester bleeding because if placenta previa is present severe

hemorrhage may result.

DIFFERENTIAL

Placental previa versus preterm labor

DIAGNOSIS

■ The diagnosis is made clinically: Third trimester vaginal bleeding with ab-

dominal pain/tenderness.

■ Ultrasound is essential to rule out placenta previa; abruption is often diffi-

cult to visualize on ultrasound.

TREATMENT

■ Assess hemodynamics and fluid resuscitate if needed. Send CBC, PT,

PTT, fibrinogen levels and type, and Rh. Fibrinogen levels tend to be low

in patients with placental abruption.

■ Monitoring of maternal contractions and fetal HRprovides an indica-

tion of fetal health and is the preferred method of evaluating patients with

possible abruption.

Painfulthird trimester vaginal

bleeding = abruption.