Anesthesia for Fetal Surgery: Twin Reversed Arterial Perfusion Sequence

Abstract

It is important to consider the fetal, uteroplacental, and matemal issues when choosing anesthetic technique for fetal surgery. The twin reversed arterial perfusion (TRAP) sequence, or the acardiac anomaly, occurs in 1:100 monozygous multiple pregnancies and in 1:35,000 births. The TRAP sequence is characterized by placental vascular arterio-arterial anastomosis between twin fetuses, one an acardiac/acephalic twin that receives its blood flow from the normal pumping twin, thereby endangering the normal twin by high output cardiac failure. The acardiac twin is nonviable, and perinatal mortality in the pump cotwin exceeds 50% because of cardiac failure and prematurity. This can be managed by fetal surgery. We report on a patient with a 26-wk gestation complicated by an acardiac/acephalic fetus anesthetized for surgical umbilical cord ligation. (Korean J Anesthesiol 2002; 42: 690-693)