incidence and etiology of chylothorax after congenital heart surgery in children

background: chylothorax is a rare but serious postoperative condition with a high rate of morbidity and may lead to the mortality of children undergoing congenital heart disease (chd) surgery. this study evaluated the specific surgical procedures associated with the higher risk of postoperative chylothorax. methods: w e assessed 435 cases undergoing chd surgery between april 2003 and may 2006. we detected postoperative chylothorax in 6 patients. the diagnosis of chylothorax was established based on the presence of an odorless fluid with the characteristic milky appearance of the fluid (except when the patients were fasting in the immediate postoperative period), a triglyceride level greater than 110 mg/dl or between 50 and 110 mg/dl with a pleural fluid white cell count greater than 1000, and more than 80% lymphocytes on differential when the pleural fluid was not chylous. results: over a 37-month period, 435 (mean age = 51.6 months; 232 males) patients underwent various types of surgical procedures for chd; 6 patients developed chylothorax after the fontan operation; one patient died due to severe chylothorax;3 patients were managed by nutritional modifications, diuretics, and thoracocentesis; and  2 patients required thoracic duct ligation. the fisher exact test analysis showed a significant association between the fontan operation and postoperative chylothorax (p value < 0.0001). conclusion: our study showed a significant association between the fontan surgery and chylothorax.