Veterinary Medicine - September 2008 - (Page 497)

worn for multiple days postoperatively. The rest of the physical examination ndings were unremarkable. A thoracic ultrasonographic examination revealed pleural effusion, and 150 ml of chyle was aspirated. Two-dimensional echocardiography was performed, and the ndings were unremarkable. Prescription Diet Feline w/d (Hill’s Pet Nutrition) was initiated to lower the fat content of the cat’s diet. The owner declined our recommendation to administer rutin because of dif culty in giving oral medication to the cat. The therapeutic plan included regular recheck examinations and thoracenteses with ultrasound guidance as needed. The cat was examined one week, three weeks, and seven weeks later, and thoracentesis yielded 90, 115, and 170 ml of uid, respectively. The cat was reportedly doing well, and the physical examination ndings were unremarkable. Second surgery The cat received the same anesthetic and analgesic protocol as in the rst surgery. A ventral midline laparotomy was performed. The incision was extended cranially over the caudal thorax. The left crus of the diaphragm was incised to expose the caudal thoracic aorta. The abdominal incision was extended farther cranially to perform a caudal median sternotomy to improve visualization. No rents in the thoracic duct or cisterna chyli were noted grossly. No evidence of brosing pleuritis was present. All blood and lymphatic vessels grossly visible in the mediastinum dorsal and lateral to the caudal thoracic aorta were ligated with several medium hemoclips. Methylene blue (< 0.5 ml of a 1% solution) was then injected directly into a mesenteric lymph node. Good lling of the dye in the abdominal lymphatic tree was noted. Methylene blue could be seen up to the diaphragm, but no dye was visible in the thoracic cavity on either side of the mediastinum. No lling cranial to the ligatures could be demonstrated, even after 10 minutes, and abdominal lymphatic lling was still good. A caudal subtotal pericardiectomy was performed, removing a 2-x-2-x-2-mm nodule on the surface. After lavage and suction, the diaphragmatic incision was repaired, and an indwelling Companion Port and chest tube were placed on the left side between the ninth and tenth ribs. Simple interrupted sutures (2-0 polydioxanone) were placed to secure the Companion Port to the thoracic wall, and the dermal layer was closed over the Companion Port with a simple continuous suture pattern using 3-0 nylon. The diaphragmatic rent, caudal sternotomy, linea alba, and subcutaneous and dermal layers were closed routinely. Postoperative treatment was identical to that described above and consisted of intravenous uids, carprofen, cefazolin, morphine, and a transdermal fentanyl patch. The cat was stable overnight, and 35 ml of pleural uid was removed through the chest tube. The pleural uid was serosanguineous, and a sample was submitted for bacterial culture and cytologic examination. The cytologic ndings were consistent with mild suppurative in ammation; the report described the uid as slightly orange-tinged with 2,160 white blood cells/µl composed of 80% degenerate neutrophils, 10% macrophages, and 10% lymphocytes. The protein concentration in the pleural uid was 3.2 g/dl. No infectious agents were seen. Aerobic and anaerobic bacterial culture results were negative. Postoperative radiographs (Figures 2A & 2B) revealed mild pleural effusion. Histologic diagnosis The pericardial histologic diagnosis was mild chronic lymphocytic pericarditis with THIRD PRESENTATION About three weeks after the last thoracentesis (10 weeks after the thymic cyst removal), the cat was presented for evaluation of dyspnea. Thoracic ultrasonography revealed severe pleural effusion, and thoracentesis yielded 500 ml of chyle. The cat stabilized during the thoracentesis and was eupneic after the procedure. Two possible causes of the chylothorax included disruption of the thoracic duct at surgery and idiopathic disease. We decided to do a thoracic duct ligation and partial pericardiectomy and to place an indwelling Companion Port (Norfolk Vet Products) and chest tube. Results of a preoperative complete blood count and serum chemistry prole were unremarkable. The owner was informed of potential complications of the thoracic duct ligation and partial pericardiectomy: The chylothorax might not resolve, brosing pleuritis could cause respiratory dif culties despite resolution of the chylothorax, serosanguineous effusion could occur after the thoracic duct ligation and partial pericardiectomy, or the cat might not survive the surgery. Postoperative treatment Postoperatively, the cat appeared stable. The patient’s renal parameters (BUN and creatinine concentrations), electrolyte concentrations (sodium, potassium, and chloride), packed cell volume, blood pressure, and body temperature were normal. VETERINARY MEDICINE September 2008 497 http://stokespharmacy.com http://stokespharmacy.com

Table of Contents Feed for the Digital Edition of Veterinary Medicine - September 2008

Veterinary Medicine - September 2008 Contents Leading Off Practical Matters Idea Exchange A Challengin Case: Thymic Cyst and Recurrent Chylothorax in a Cat 10 Life-Threatening Behavior Myths CE Form Advertiser Index Marketplace/Classifieds Mind Over Miller

Veterinary Medicine - September 2008

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