Natural orifice transluminal endoscopic surgery: A transtracheal approach for the thoracic cavity in a live canine model

Background: The present study aimed to evaluate the performance of transtracheal thoracic exploration and pericardial window creation in a canine survival model. Methods: Transthoracic exploration was performed in 14 dogs. Under general anesthesia, after an incision in the right lateral wall of the middle-lower portion of the trachea was made, a 9-mm metal tube was advanced into the thoracic cavity. For thoracic cavity exploration and pericardial window creation, a flexible bronchoscope was introduced through the metal tube into the thoracic cavity. After thoracoscopy, a Dumon stent (Novatech, Grasse, France) was used to cover the tracheal incision site and facilitate healing. Animals were evaluated by endoscopy 1 and 2 weeks later. Animals were humanely killed, and necropsy was performed 2 weeks after the transtracheal natural orifice transluminal endoscopic surgery. Results: Fourteen dogs underwent transtracheal thoracic exploration lasting for an average of 110 minutes (range, 80-150), with 3 perioperative deaths. At 2 weeks after pericardial window creation, endoscopy revealed normal healing of the tracheal incision sites in all 11 surviving animals. Necropsy on the 11 animals at 2 weeks showed 9 adhesions around the pericardial window and 5 adhesions around the tracheal incision region. No mediastinitis or abscesses could be identified. Conclusions: Transtracheal thoracic exploration is technically feasible. Increasing surgical experience together with improvement in endoscopic techniques will further facilitate the development of natural orifice transluminal endoscopic surgery for thoracic diseases. (J Thorac Cardiovasc Surg 2011;141:1223-30)