En bloc thoracic duct ligation and subtotal pericardectomy in dogs and cats with idiopathic chylothorax by thoracotomy versus thoracoscopy in 20 cases (2005-2013)

Abstract

Chylothorax is a devastating disease in dogs and cats. A golden standard for treatment of idiopathic chylothorax has not been described yet. Goals for this study were to evaluate en bloc TDL and SP as a treatment for idiopathic chylothorax and to compare outcomes of treatment by thoracotomy and thoracoscopy. 16 dogs and 4 cats with idiopathic chylothorax, that were surgically treated between 2005 and 2013 at the Faculty of Veterinary Medicine Utrecht, were studied retrospectively. In 15 patients thoracotomy was performed during surgery, the other 5 were operated thoracoscopically. All patients had en bloc TDL performed in combination with SP, except for 3 dogs that were treated with en bloc TDL only. Overall 9 out of 17 patients (53%) became disease free. Success for thoracotomy was 50% and 60% for thoracoscopy, this difference turned out to be not significant. For patients treated with both en bloc TDL and SP success was 47%. In this group thoracotomy only had successful outcomes in 40% of patients, which is also not significantly different from the 60% success with thoracoscopy. The mean survival time for both treatment techniques was also similar. Together with decreased hospitalization time, post-operative pain and morbidity previously reported for the less invasive thoracoscopy, this treatment technique might be preferred over the classic thoracotomy. The success rate for the combined treatment with TDL and SP was, for unknown reason, lower than expected. Despite this outcome the combination of en bloc TDL and SP is still considered to be a good treatment option for idiopathic chylothorax. Further research for new lymph drainage routes formed after en bloc TDL and for the role of high venous pressure and SP on lymph drainage is needed. Moreover gaining more understanding about the etiology of idiopathic chylothorax and persistent nonchylous effusion after treatment should be subjects of ongoing study.