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Intrafetal Fluid Effusions and Pulmonary Growth after Pleuroamniotic Shunt in Fetuses with Severe Hydrothorax
Fredal Sánchez-Martínez1, Andrea Peláez-Jiménez1, Ramiro Rojas-Pillaca1
1Prenatal Diagnosis and Fetal Surgery Center, Instituto Medicina Fetal Mexico, Queretaro/Guadalajara, Mexico.
Introduction:
The aim of this study was to assess the longitudinal intrathoracic changes after pleuroamniotic shunting (PAS) in fetuses with massive unilateral or bilateral hydrothorax.
Methods:
The presence of intrafetal fluid effusions and the observed/expected lung-to-head ratio (O/E-LHR) of both lungs were weekly evaluated in a cohort of fetuses with severe hydrothorax treated PAS in a single reference center in Mexico. Severe fetal hydrothorax was diagnosed as an accumulation of fluid within the fetal pleural space accompanied with severe bilateral lung compression, mediastinal shift, polyhydramnios, and/or hydrops. The longitudinal changes in intrafetal fluid effusions, and pulmonary growth were analyzed by survival and multilevel analysis against weeks after fetal intervention.
Results:
Fifty-six pregnancies with severe fetal hydrothorax were treated with PAS at a median gestational age of 30.1 (range, 20.8-36.1) weeks. After shunting, all cases were longitudinally analyzed and in whom a total of 332 scans were performed (median 6, range 2-16). A complete disappearance of hydrops and hydrothorax was observed at a median interval of 1.6 and 5.9 weeks after PAS, respectively. A progressive increase in lung growth was observed, becoming normal O/E-LHR at on average 7.0 weeks after PAS.
Conclusion:
Fetal PAS promotes disappearance of all fetal fluid effusions and a normalization of the pulmonary growth after fetal intervention.
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