Small Animal Surgical Resident UW Veterinary Care Cottage Grove , Wisconsin
Treatment of chylothorax in dogs with thoracic duct (TD) ligation and cisterna chyli ablation is relatively successful. However, failure due to development of collateral lymphatics bypassing the TD ligation is problematic. Direct anastomosis of the TD to an intercostal vein (ICV) would maintain lymphatic flow from the abdomen to the venous system and potentially prevent lymphatic hypertension and stimulus for collateral circulation.To describe the technique for anastomosis of the TD to the 10th or 11th ICV using a microvascular coupler device (MCD) in dogs and to assess patency on days 0 and 30.Six adult beagle dogs were involved in this study. Under general anesthesia, popliteal lymphangiography was performed and the TD identified. A right 9th or 10th intercostal thoracotomy was performed. Using an operating microscope, the TD and ICV were isolated, ligated, and anastomosed using a 1.5mm or 2.0mm MCD. Popliteal lymphangiography was repeated immediately after surgery and on day 30.The anastomosis was successful and lymphangiography documented flow into the azygos vein in all 6 dogs immediately after surgery and in 4 of 6 dogs on day 30. In the remaining dogs, kinking of the ICV obstructed flow through the anastomosis.TD-ICV anastomosis using a MCD is feasible and can maintain patency up to 30 days. Further investigation is warranted to assess the efficacy of this technique in clinically affected dogs.Direct lymphaticovenous anastomosis may have application for treatment of chylothorax by maintaining flow from the abdominal lymphatics and thereby preventing collateral circulation and persistent chylous effusion.
