VASA PREVIA.pptx

Praevia

1. VASA PREVIA Dr.Regan, MD

2. Definition Rupture of a fetal vessel • Result of a velamentous insertion of the umbilical cord into the membranes – Veins travel across the amniotic membranes before coming together in umbilical cord

3. Pathophysiology This is a situation where blood vessels (or their branches) in the umbilical cord develop a route away from the cord and placenta proper and are found just above the cervical opening That means they are, in effect, between the baby’s leading part (usually the head) and the cervical opening Once the cervix starts dilating, the delicate vessels will be stretched and will soon tear. This will unleash torrential vaginal bleeding.

4. Risk factors A low lying placenta (placenta praevia) Multiple pregnancy (twins or more ) A placenta where the cord insertion is peripheral rather than central ( velamentous insertion of cord) IVF pregnancy: For some obscure reason, IVF pregnancy increases the risk of vasa praevia almost 10-fold to an estimated 1 in 300. Previous history of uterine surgery including minor procedures such as D&C

5. ALTERATIONS IN THE FETAL HEART RATE Initial fetal tachycardia—fetus attempts to compensate for acute blood loss Bradycardia Intermittent accelerations Note that; Fetal mortality reported to be greater than 50% Hence you must make diagnosis rapidly and institute definitive therapy and delivery

6. Investigation APT TEST Used to detect fetal blood . • The blood is mixed with a small amount of tap water to cause hemolysis . The sample is next centrifuged for several minutes . The pink hemoglobin-containing supernatant is then mixed with 1 mL of 1% NaOH for each 5 mL of supernatant. The color of the fluid is assessed after 2 minutes. Fetal hemoglobin will stay pink and adult hemoglobin will turn yellow-brown.

7. Management Consider hospitalization in the third trimester to provide proximity to facilities for emergency cesarean delivery. Fetal surveillance to detect compression of vessels. Antenatal corticosteroids to promote lung maturity. Elective cesarean delivery at 35 to 36 weeks of gestation. Avoid amniotomy as the risk of fetal mortality is 60-70% with rupture of the membranes

8. THE END ANY QUESTION……..?????????