Percutaneous umbilical transfusion in severe rhesus isoimmunization: resolution of fetal hydrops.

The rhesus-sensitized fetus with the worst prognosis is one with early onset of hydropic changes. Percutaneous umbilical blood sampling now enables access to the fetal circulation and thereby allows more precise evaluation of fetal anemia and direct intravascular transfusion. A variation of this technique was used in three pregnancies complicated by fetal pericardial effusion, scalp edema, and abdominal ascites before 26 weeks' gestation. Twelve ultrasound-guided percutaneous transfusions of 30 to 85 ml packed red blood cells were administered into the umbilical cord at its placental insertion. In each fetus the hydropic changes completely resolved and pregnancy outcome was successful. Neither adjunctive therapy with digoxin or Lasix nor exchange transfusions were used. Percutaneous umbilical transfusions appear to have the potential to improve the prognosis for the severely isoimmunized fetus.