Intrathoracic dislodgement of pleuro-amniotic shunt. Three case reports with long -term follow-up

Intrathoracic shunt dislodgement is a rare, although significant, complication of pleuro-amniotic shunting. In a previously reported case, the abnormally located shunt caused constriction of the pulmonary hilum resulting in neonatal death.

Three cases of severe fetal pleural effusion treated by pleuro-amniotic shunting at 33, 26 and 30 weeks of gestation and complicated by dislodgement of the shunt into the fetal chest are presented. These cases were collected from three fetal medicine referral centers, where 15 pleuro-amniotic shunts have been inserted in a total of 13 fetuses (11 unilateral and 2 bilateral procedures), giving prevalence for this complication of 20%. The indication for shunting was severe bilateral pleural effusions and hydrops in one case, and unilateral pleural effusion with marked mediastinal shift in 2 others. Intrathoracic dislodgement was diagnosed by ultrasound at 33, 29 and 39 weeks, and the infants were delivered at 35, 34 and 39 weeks of gestation, respectively. There were no complications associated with the malposition of the shunt within the fetal chest and clinical follow-up from 10 months to 2 years of age has demonstrated asymptomatic infants.

The complication of intrathoracic dislodgement of a pleuro-amniotic shunt can be recognized prenatally by ultrasound. Prevention of this complication seems difficult, but if recognized, a conservative approach appears to be a sensible management option. Since the material of the shunt is inert, its presence within the pleural cavity is unlikely to be associated with an inflammatory foreign body response and, therefore, it should not cause long-term pulmonary complications.