Postcaval thrombosis and delayed shunt migration after pleuro-peritoneal venous shunting for concurrent chylothorax and chylous ascites in a dog.

Simultaneous chylothorax and chylous ascites related to intestinal lymphangiectasia was diagnosed in a 4-year-old spayed female dog. Palliative pleural and peritoneal drainage was accomplished by placement of fenestrated silastic sheeting into surgically created diaphragmatic defects, and implantation of a pleuro-peritoneal venous shunt. The immediate postoperative period was complicated by acute renal failure secondary to postcaval thrombosis originating at the site of placement of the efferent pump catheter and extending to the level of the renal veins. Rapid resolution of this complication was accomplished with systemic anticoagulation. Clinical signs related to fluid accumulation resolved for 10 weeks after which acute decompensation occurred and the dog was euthanatized. Postmortem examination showed that reaccumulation of fluid was associated with migration of the efferent limb of the shunt from the caudal vena cava.