Thoracoscopic Thoracic Duct Ligation

Abstract

Chylothorax is the presence of chyle in the thoracic cavity due to a disruption of the thoracic duct. The cause of chylothorax includes congenital malformation, trauma, neoplasm, and inflammation. Complications of chylothorax are severe and include significant nutritional deficiency, immunocompromised status, and metabolic derangements. These complications are a result of the rich composition of chyle. Chyle contains dietary fats absorbed enterally, fat-soluble vitamins, protein, and T-cell lymphocytes. 1 The composition of chyle is similar to that of plasma in terms of electrolytes. Losingasignificantamountofchylecanleadtothedisastrous consequencespreviouslylisted.Thediagnosisofchylothorax is confirmed by sampling the pleural effusion with a triglyceride level 110 and by the presence of chylomicrons.1,2 Management of chylothorax begins with drainage of chyle from the pleural cavity by either tube thoracostomy or an image-guided percutaneous drain. Medical management involves diet modification through 2 modalities. The first is a low-fat diet, rich in medium-chain fatty acids, as this will bypass the thoracic duct via direct absorption in the portal vein. Strict nil per os and total parenteral nutrition are the other modalities used as bowel rest decreases the amount of chyle flowing through the thoracic duct. Somatostatin has been found to decrease the volume of chyle by decreasing absorption in the gastrointestinal tract. 3 This has been used primarily in the pediatric population with sparse case reports in the adult literature. 4 Surgical management includes several therapeutic options. Surgical management is indicated for 1 L or greater of chyle drainage over a 24-hour period or for patients who fail to stop leaking chyle with conservative therapy. Pleurodesis, via talc or fibrin glue, has been used with reported success. 5 The placement of a Denver pleuroperitoneal shunt has been used in patients who are nonoperative candidates; however, these shunts are fraught with complications such as tenderness from the catheter site, obstruction, and patient noncompliance. 6 Thoracic duct embolization via percutaneous catheterization and lymphography is another option. This technique is successful in approximately 70% of cases in which the thoracic duct can be cannulated. 7 Moredefinitively,thethoracicductcanbeligated,through either isolation or mass tissue ligation, as discussed later. 5,8,9