EXIT-to-resection for fetuses with large lung masses and persistent mediastinal compression near birth.

Purpose: To identify prenatal diagnostic features that will help select fetuses with lung masses (LM) who may benefit from ex-utero intrapartum treatment (EXIT procedure) as the preferred mode of delivery.

Methods: The CCAM-volume ratio (CVR), fetal treatment, and outcomes of all fetuses with LM evaluated between 2001 and 2011 were reviewed retrospectively. Fetuses with hydrops or CVR>1.6 were classified as high risk. Indications for fetal interventions included hydrops and heart failure, and indication for EXIT-to-resection was the finding of persistent mediastinal compression (PMC) near birth.

Results: Of 110 fetuses evaluated for LM, 78 were classified as low-risk. No fetus in this group had PMC near birth and none required perinatal treatment. Of 32 high-risk fetuses, 8 developed heart failure of which 4 survived (3 following fetal surgery). Nine high-risk fetuses with no PMC near birth were asymptomatic postnatally and treated electively. Sixteen high-risk fetuses had PMC near birth. All 9 babies with PMC treated with EXIT-to-resection did well with discharge at a median of 10 days post-operatively. All 7 fetuses treated without an EXIT developed respiratory distress following birth requiring an urgent operation; 2 died.

Conclusion: The EXIT-to-resection procedure is a favorable delivery approach for those fetuses with large LM and PMC near birth.