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An Urban Experience
G. Dupré1
1Dipl. ECVS, Dipl. Human thoracoscopy and interventional pneumology, Clinic for Small animal Surgery, Veterinary Medicine University of Vienna, Veterinaerplatz 1, 1210 Vienna
Learning Outcomes
Through this lecture, the practitioner
• shall be able to expand his/her current indications for pericardectomy
• understand the pros and cons of the thoracoscopic approach
• get an overview of the different thoracoscopic approaches
The aim of the creation of a window in the pericardium
or the performance of subtotal pericardectomy is to establish permanent drainage for patients with pericardial effusion. Pericardectomy is considered to be the definitive treatment for recurrent benign or idiopathic pericardial effusion and constrictive pericarditis. This procedure is advocated as a palliative treatment for malignant pericardial effusion. Pericardectomy was
also recently recommended as an additional surgical procedure for the treatment of chylothorax in both
dogs and cats. In a previous study of dogs with ultrasonographically detected pericardial effusion without cardiac masses, the median survival time was 1218 days among dogs that underwent pericardectomy and 532 days among dogs that underwent conservative management. Another study of dogs with heart-base tumors found a prolonged median survival time of 730 days among dogs that underwent pericardectomy
and only 42 days among dogs that did not undergo pericardectomy.
The first publication on thoracoscopic pericardectomy in the field of veterinary medicine appeared in 1999. In early studies, thoracoscopic pericardectomy was associated with less postoperative pain and lower morbidity than traditional open thoracotomy and had the additional benefit of offering better visualization secondary to improved illumination and magnification of previously inaccessible areas. More recently, pericardectomy has also been performed thoracoscopically in association with concurrent right atrial tumor removal and thoracoscopic management of chylothorax.
Thoracoscopic creation of a 4- to 5-cm-diameter pericardial window has been recommended to palliate the clinical signs associated with pericardial effusion in dogs. In the study upon which this recommendation
is based, all dogs exhibited immediate resolution of cardiac tamponade following thoracoscopic partial pericardectomy. However, 77% of dogs had neoplastic pericardial effusion, and long-term follow-up was available for only two dogs with idiopathic pericardial effusion. Consequently, no conclusions could be made regarding the long-term outcome of dogs with idiopathic pericardial effusion that underwent the pericardial window procedure. Whether a 4- to 5-cm pericardial window
is large enough for long-term palliation of the clinical signs in dogs is unknown. Creation of a larger pericardial window or the performance of subtotal pericardectomy when performing thoracoscopic pericardectomy
may be advisable. In one study, dogs with idiopathic pericardial effusion treated by thoracoscopic creation of
a pericardial window had significantly shorter disease- free intervals and median survival times that did dogs treated by subtotal pericardectomy via thoracotomy
(P < 0.05). However, no significant differences were found between the two groups for dogs presented with neoplastic pericardial effusion. The authors suspected that this difference in the outcome may have been
related to inaccuracy of the initial diagnosis (the excised pericardium was too small for accurate histopathologic diagnosis) or the inability of the pericardial window to palliate the signs of idiopathic pericardial effusion in the long term.
Three approaches to thoracoscopic pericardectomy have been described depending on whether the patient is in lateral, dorsal, or sternal recumbency (when combined with thoracic duct surgery). Given the short operative duration and sterile surgical environment, intraoperative broad-spectrum antibiotics are sufficient; postoperative antibiotic therapy is usually unnecessary.
The patient and port positions depend mainly on the surgeon’s preference and patient’s disease. Dorsal recumbency is generally preferred in most patients. Although lateral recumbency is most often preferred
in patients with heart-base tumors, some authors reportedly select dorsal recumbency for such patients.
Thoracoscopy in dorsal recumbency avoids the need
for selective intubation, maintains bilateral lung function, and is not technically demanding. With the patient in this position, the first trocar camera can be entered either between the last ribs at the sternocostal junction [26]
or in a paraxiphoid or subxiphoid location (between the xiphoid process and the last sternocostal junction or just caudal and dorsal to the xiphoid process). In the two latter cases, the scope is entered transdiaphragmatically.

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