Postoperative chylothorax in children: differences between vascular and traumatic origin.

Twenty-four children with postoperative chylothorax were encountered among 1,264 consecutive thoracic operations over a 7-year period and form the basis of this study. Chylothorax was caused by direct lesion to the thoracic duct or lymphatic vessels in 17 patients and was associated with superior vena cava (SVC) obstruction in seven. Of the latter, five had bilateral chylothorax. Chylothoraces secondary to venous hypertension and thrombosis have a longer interval between operation and diagnosis compared with direct trauma as well as a longer duration and larger volume of chylous drainage. Treatment was entirely nonoperative in 16 patients and operative in 8. Nonoperative treatment consisted of pleural needle aspiration or suction drainage in association with a medium chain triglyceride (MCT) diet (n = 11) or total parenteral nutrition (TPN) after failure of MCT (n = 5). Direct operation on the thoracic duct was performed in 5 patients, four had pleurodesis, and 2 had pleuroperitoneal shunts inserted. All patients were cured of their chylothorax and there were no deaths. Patients with major vein thrombosis were the most difficult to treat. On the basis of this experience, we suggest a step-by-step approach: (1) insertion of chest tube after 3 to 4 pleural punctures; (2) 1-week trial of MCT diet, with intravenous support to correct protein losses; (3) TPN if chylothorax increases or persists with large volumes; (4) Doppler echocardiography or phlebography to rule out obstruction of major thoracic veins; and (5) insertion of TPN line in inferior vena cava in case of such obstruction; and (6) direct surgical approach to the thoracic duct after 4 weeks of unsuccessful nonoperative treatment.(ABSTRACT TRUNCATED AT 250 WORDS)