Predicting Outcome in Primary Fetal Hydrothorax

Objective: This study examines the role of serial ultrasound in predicting fetal outcomes based on progress, resolution or stability of pleural effusions in primary fetal hydrothorax (PFHT). Methods: Records from consecutive cases of fetal pleural effusions referred to the fetal echocardiography unit over a 12-year period were reviewed. Study patients underwent thorough investigation to rule out secondary causes of pleural effusions. The clinical course was monitored with serial ultrasound studies every 2 weeks until delivery. Pleurocentesis and pleuroamniotic shunts were performed in select cases of PFHT. Fetal survival was the primary outcome variable. Results: Eighteen of 44 patients referred for perinatal evaluation of fetal pleural effusions met the study criteria for PFHT. Diagnosis was made at 28 ± 7 weeks and fetuses delivered at 35 ± 3 weeks’ gestational age. Overall survival was 78%. Effusion progression, greater effusion ratios, earlier gestational age at delivery, and lower Apgar scores at birth were associated with poor outcome. Conservative management was appropriate for most cases. Conclusions: Serial ultrasound studies to evaluate the clinical course of the pleural effusions are essential in the management of PFHT. Expectant management of stable and resolving effusions was appropriate in all cases.