ABSTRACT
Chylothorax results from the leakage of chyle from the thoracic
duct into the pleural cavity. Although it is rare, it is a well-
established clinical entity and is the most common cause of
pleural effusion in the fetus and neonates.13 Whether
chylothorax is congenital or acquired, it frequently resolves
with nonoperative measures aimed at optimizing ventilation
and maintenance of nutrition. Relatively new on the horizon,
somatostatin and its synthetic analog octreotide lend optimism
to the possibility of adding new therapies to the current
nonoperative treatment armamentarium.4 When these mea-
sures fail to effect spontaneous healing, operative management
becomes imperative. For patients in whom resolution does not
occur, persistent chylothorax can become a life-threatening
disorder, with profound respiratory, nutritional, and immu-
nologic consequences.1,57 While early diagnosis, aggressive
initiation of nonoperative management options, and a number
of alternative surgical procedures have significantly decreased
the mortality rate from 50% before the 1950s8,9 to current
estimates ranging from 6 to 21%,1015 significant morbidity
continues. This chapter presents an overview of key clinical
aspects of fetal and neonatal chylothorax. A basic description
of the anatomy and embryology of the lymphatic system and
the pathophysiology of chyle provide the foundation for
understanding this disorder. Other pleural effusions, including
empyema and hemothorax, will also be briefly discussed. Since
malignant effusions rarely occur in neonates, they have been
omitted from the discussion.
