(740) Etiologic Factors and Complications of Chylothorax in Children: A National Database Study

Introduction: Chylothorax is a rare condition in children. It is a significant cause of morbidity and prolonged hospitalization. The goal of this study was to elucidate the demographics, etiologies, complications, and outcomes of hospitalized children with chylothorax in the U.S.

Methods: A retrospective analysis of the Healthcare Cost and Utilization Project (HCUP) 2016 and 2019 Kids’ Inpatient Database (KID) was performed. Chylothorax and etiological factors were identified using ICD 10 codes. Univariate analysis was used to compare children with chylothorax and all other discharges along with outcomes in various etiologies.

Results: Of 12,166,586 discharges, chylothorax was documented in 2,237 (18.4/10,000 discharges). Most patients with chylothorax were infants (39.8%) and neonates (24.3%), and 1.2% were late adolescents. The etiologies for chylothorax included cardiac surgical procedures (60.2%), central venous line (CVL) in major neck veins (26.6%), non-cardiac surgical procedures (12.5%), congenital (2.4%), and other causes (0.8%). Cardiac surgical procedure was common among neonates and infants. Whereas, CVL and non-cardiac surgery were more frequent in late adolescence. Compared to all other discharges, coagulopathies (OR=11.97, 95%CI: 10.24-13.99), malnutrition (OR=11.82, 95%CI: 8.56-16.32), immunodeficiency (OR=6.97, 95%CI: 2.89-16.81), lymphopenia (OR=37.70, 95% CI: 21.79-65.22) and bacterial sepsis (OR=6.30, 95%CI: 5.57- 7.12) were more common in patients with chylothorax. Chylothorax management interventions included the use of total parenteral nutrition (22%), drainage of the fluid (36.1%), and procedures such as thoracic duct embolization or ligation, pleurodesis, pleuro-peritoneal shunt, and pleurectomy (5.2%). The median length of stay was 2 (IQR 2-3) days, and the mortality rate was 6.6%. The risk of mortality was highest when the chylothorax was associated with non-cardiac surgical procedures (OR=3.67, 95%CI: 2.60-5.18).

Conclusions: In this cross-sectional study, the national prevalence of chylothorax in hospitalized children is 18.4 per 10,000 discharges. The risk factor for chylothorax varies with the age of children. Cardiac procedures are the primary risk factor for chylothorax, but patients with non-cardiac surgical procedure-related chylothorax have the highest mortality.