Umbilical cord occlusion

Umbilical cord occlusion in twin–twin transfusion syndrome

As discussed in Chapter 9, the surgical treatment of twin–twin transfusion syndrome (TTTS) involves primarily laser obliteration of the anastomoses responsible for the syndrome. Occasionally, however, selective feticide of one of the fetuses must be contemplated. 

Indications for selective feticide in TTTS include a discordant anomalous twin or failed attempted laser therapy. The former are classified as being primary, the latter as being secondary selective feticides. Occasionally, patients may choose primary selective feticide after counseling, in accordance with their own personal opinions regarding potential outcomes. 

Conventional methods for selective termination in non-monochorionic multiple gestations involve injection of potassium chloride into the vascular system of the target fetus. This is not appropriate in pregnancies complicated by TTTS, which by definition are monochorionic and have placental vascular communications.1 Selective feticide in pregnancies complicated by TTTS must involve interruption of blood flow to one fetus while avoiding damage to the other fetus. 

Quintero et al described the first successful umbilical cord occlusion for the treatment of acardiac twins,2 involving extracorporeal suture ligation of the umbilical cord of the target fetus. This technique was further expanded to the treatment of other complicated monochorionic twin pregnancies, including severe TTTS with a discordant lethal anomaly or with critically abnormal Doppler studies or hydrops. 

Other methods of umbilical cord occlusion (UCO) have been developed to achieve this end.2–14 UCO typically requires access to the amniotic cavity of the target twin. In the case of the recipient twin, this is readily accomplished because of the presence of polyhydramnios. However, access to the donor’s cord may be hindered by the presence of severe oligohydramnios. A study was conducted at our institution to compare the operative characteristics and clinical outcomes of UCO of the donor vs the recipient twin in complicated TTTS pregnancies.