(369) Chemical Pleurodesis: Alternative Treatment of Chylothorax in a Pediatric Patient

Introduction: Chylothorax is a rare condition caused by an accumulation of chyle in the pleural cavity most commonly seen after traumatic disruption of the thoracic duct. The etiology can be divided into non-traumatic, traumatic, and idiopathic. In the post-operative patient, a chylothorax may be first detected as a pleural effusion or persistent “milky” drainage from the chest tubes. The diagnosis is confirmed if pleural fluid analysis shows a triglyceride level of more than 110 mg/dL or the presence of chylomicrons. Current management includes dietary modification, somatostatin analogs, thoracentesis, mechanical pleurodesis, thoracic duct ligation, and/or thoracic duct embolization.

Description: 12 month old female with DORV (tetralogy-type) with severe pulmonary stenosis underwent RVOT stenting and collateral occlusion, followed by a complete valve-sparing repair with VSD closure, infundibular muscle resection, and RVOT patch augmentation. Her post-op course was complicated by prolonged high-output right chylothorax. She was managed initially with NPO and TPN, then, octreotide, steroids, MCT oil, with improvement and finally, transitioned to Enfaport formula with recurrence of chylothorax. She then completed a 5-day course of chemical pleurodesis with doxycycline with complete resolution of her chylothorax.

Discussion: Persistence of chylothorax can lead to malnutrition, weight loss, and impaired immunity. The initial approach is conservative management with fluid and electrolyte replacement, appropriate nutrition, somatostatin analog infusions, and thoracentesis. If unresponsive to conservative management, surgical ligation of the thoracic duct is considered, and if this fails, pleurodesis has been well described in the treatment of adult pleural effusions. There is limited data regarding its safety and efficacy in pediatrics. Our patient received chemical pleurodesis with 4 mg/kg of doxycycline, through an existing pig-tail catheter, for 5 days with complete resolution. We instilled a 30 mL mixture of lidocaine, doxycycline, in sterile water over 10 minutes, dwelled for 2 hours and then drained. We describe the successful use of chemical pleurodesis with doxycycline for the treatment of pediatric chylothorax and the potential to avoid invasive surgical interventions.