| Popis: |
The intrauterine death of one monochorionic twins is associated with an increased mortality risk for the co-twin, probably a result of acute hemodynamic changes occurring when the survivor exsanguinates into the dead fetus as its blood pressure plummets. Twin-to-twin transfusion syndrome (TTTS) is a more severe form of hemodynamic instability. The present study of 12 cases of single intrauterine death in monochorionic pregnancies was an attempt to learn the value of fetal blood sampling and intrauterine transfusion (IUT) for rescuing the surviving twin within 24 hours of the co-twin's death. In all cases the twin death occurred at 17 to 26 weeks' gestation in the presence of TTTS that had been treated by either laser therapy or serial drainage of amniotic fluid. Within 24 hours of one twin's death, ultrasound-guided blood sampling was carried out at the placental cord insertion site in the surviving twin using a 20-gauge needle. If the surviving twin was anemic, intrauterine transfusion began at the same time. Weekly anomaly scans and Doppler studies ensued, and magnetic resonance imaging was done at 32 weeks' gestation Drainage of amniotic fluid was carried out in four cases, and laser coagulation alone was performed in six. One patient had both, and one had a laser procedure followed by cord coagulation. Seven recipient twins and five donors died, all of them within 3 days of the procedure. Six of the 12 surviving fetuses were anemic and underwent IUT; only 2 of them had major ultrasound findings of fetal anemia, and other biophysical findings were normal. One pregnancy was ended because of periventricular leukomalacia. Two fetuses delivered close to term were neurologically normal at age 12 months. Two others delivered prematurely (2 and 4 weeks after IUT) also did well neurologically. Pregnancies were uneventful for all six nonanemic fetuses, with spontaneous delivery between 34 and 38 weeks' gestation. These infants seemed normal at age 1 year with no evident hypoxic or ischemic brain injury. Fetal blood sampling is of clinical value after death of a twin in TTTS. It can identify nonanemic fetuses that are not likely to develop a cerebral lesion. Anemic fetuses, especially those not having occlusive treatment to lessen fetofetal exsanguination, remain at high risk and may benefit from IUT. |
