What is the management for a 29-year-old woman, gravida (number of times pregnant) 1, para (number of viable births) 0, at 33 weeks gestation with known vasa previa, who experienced rupture of membranes with leakage of blood-tinged fluid, and has fetal bradycardia (abnormally slow fetal heart rate)?

From the Guidelines

This patient with vasa previa who has ruptured membranes and blood-tinged fluid with fetal bradycardia requires immediate emergency cesarean delivery. The fetal heart rate of 100/min indicates fetal distress, likely due to bleeding from ruptured fetal vessels in the vasa previa, which is considered an irreversible cause of fetal bradycardia 1. Anesthesia should be notified immediately for rapid induction, and a type and cross for at least 4 units of packed red blood cells should be ordered for both mother and neonate. The neonatal intensive care team should be present at delivery.

Key Considerations

• Vasa previa is a condition where fetal blood vessels traverse the membranes over the cervical os, unprotected by placental tissue or umbilical cord, and when membranes rupture, these vessels can tear, causing rapid fetal exsanguination 1.
• The blood-tinged fluid likely represents fetal blood, and the bradycardia confirms fetal compromise.
• Even without heavy vaginal bleeding, fetal hemorrhage can be significant and rapidly fatal, with a mortality rate approaching 100% if not immediately delivered, making this one of the true obstetrical emergencies requiring immediate intervention regardless of gestational age.

Preoperative Preparation

• While preparing for surgery, large-bore IV access should be established, and crystalloid fluids should be started.
• The patient should be positioned in left lateral tilt to optimize uteroplacental perfusion.
• The decision to proceed with anesthesia in the event of failed tracheal intubation should be made in consultation with the obstetric team, taking into account factors relating to the woman, fetus, staff, and clinical situation, as outlined in the obstetric anaesthetists' association and difficult airway society guidelines 1.

From the Research

Management of Vasa Previa

• The patient is at 33 weeks gestation with a known vasa previa and has experienced rupture of membranes with leakage of blood-tinged fluid 2, 3.
• The pregnancy was the result of in vitro fertilization and has otherwise been uncomplicated, with a fetal growth ultrasound revealing a cephalic fetus with an estimated fetal weight at the 50th percentile and a normal amniotic fluid index.

Prevention of Postpartum Hemorrhage

• Studies have shown that carbetocin is probably the most effective agent in reducing blood loss and the need for additional uterotonics during cesarean delivery 3.
• Oxytocin appears to be more effective when initiated as a bolus, and bolus plus infusion regimens may lead to minor reductions in mean blood loss 4.
• The use of tranexamic acid and ergometrine may also be beneficial in preventing postpartum hemorrhage 2.

Emergency Cesarean Section

• In cases of emergency cesarean section, the implementation of a Rapid Response Team (RRT) can improve delivery intervals and contribute to maternal and infant safety 5.
• Perimortem cesarean delivery (PMCD) is a rare but potentially life-saving procedure for both mother and fetus, and emergency physicians should be aware of the procedure's indications and steps 6.

Key Considerations

• The patient's temperature, blood pressure, and pulse are within normal limits, but the fetal heart rate is 100/min, which may indicate fetal distress 2, 3.
• The uterus is nontender and has no palpable contractions, but the patient has experienced rupture of membranes with leakage of blood-tinged fluid, which may indicate the need for immediate intervention 2, 3.