New Technique for Intrathoracic Implantation of Extraluminal Spiral Prostheses in the Trachea
Background: Extraluminal surgical procedures for intrathoracic tracheal collapse in dogs are not routinely performed. The patients are normally treated with different drugs or by intraluminal stents. However, in more severe cases, drug treatment does not always have good outcomes, and intraluminal prostheses can be correlated to several postoperative problems. In order to obtain better results, we aimed to develop a surgical technique for implantation of a new extraluminal helical prosthesis in the thoracic segment of the trachea through cervical access, associated with pneumatic mediastinoscopy for certification of the technique and minimization of possible complications.
Materials, Methods & Results: Seven canine corpses (CCs) from non-traumatic death, weighing between 2 and 7 kg, were used. A ventral cervical approach to the trachea was associated with blunt mediastinal dissection. Trans cervical pneumatic mediastinoscopy was used for evaluation of the dissection and location of the implant. These were compared with the necropsy findings by the exact Wilcoxon two-sample test, with P < 0.05. The results of necropsy and mediastinoscopy did not present significant differences at P < 0.05. During the examinations, the presence of some mediastinal visceral lesions caused by the prosthesis, the integrity of the mediastinum and possible lesions to RLN and blood vessels (BV) were analyzed. We also investigated the location of the distal part of the prosthesis in the thoracic segment of the trachea and its dissection. To evaluate the technique, statistical comparison was made between mediastinoscopy and necropsy findings. The data were compared by the Wilcoxon test at 5% probability. The tracheas of all CCs were efficiently dissected, but in some cases problems that can happen during the procedure were noticed. This was checked by mediastinoscopy and confirmed by necropsy. The median of the scores was 1 (good dissection and visualization), with variance of zero for mediastinoscopy and 0.14 for necropsy. In the mediastinoscopy of one CC, the prosthesis crossed the tracheal bifurcation, involving the posterior vessels of this region, which was confirmed by necropsy. However, the dissection showed no vascular lesions. The integrity of the mediastinum was assessed only by mediastinoscopy. There was no impairment caused by any of the procedures performed. This resulted in a median score of 1 (integrity) with zero variance. When the positioning of the prosthesis was evaluated in relation to the tracheal bifurcation, identical values were obtained by both methods. The median score was 1, with variance of 0.62. No statistical differences were found between the two evaluation methods for the analyzed variables. This demonstrates the strong potential of the proposed evaluation techniques.
Discussion: Our results show that the execution of the technique is possible, but some complications may occur. Mediastinoscopy as an evaluation procedure can pose some complications, these considerations are important, but by using technique proposed in this study, these factors are minimized due to the ease of technical implantation of the extraluminal tracheal stent, without the need for several instruments competing in the inflated mediastinal space. We concluded that the technique is viable and a safe method with minimal invasion for investigation and treatment of mediastinal diseases, presenting low impairment of the paratracheal structures, and that mediastinoscopy can be used as a transoperative evaluation method to minimize complications.
Becker W.M., Beal M., Stanley B.J & Hauptman J.G. 2012. Survival after surgery for tracheal collapse and the effect of intrathoracic collapse on survival. Veterinary Surgery. 41(4): 501-506.
Beteg F., Muste A. & Lacatus R. 2010. Mediastinotomy by paratracheal approach in the dog – a preliminary report. Lucrari Stiinłifice Medicina Veterinaria. 43(2): 90-94.
Chisnell H.K. & Pardo A.D. 2014. Long-term outcome, complications and disease progression in 23 dogs after placement of tracheal ring prostheses for treatment of extrathoracic tracheal collapse. Veterinary Surgery. 44(1): 103-113.
Durant A.M., Sura P., Rohrbach B. & Bohling M.W. 2012. Use of nitinol stents for end-stage tracheal collapse in dogs. Veterinary Surgery. 41(7): 807-817.
Freitag L. & Darwiche K. 2014. Endoscopic treatment of tracheal stenosis. Thoracic Surgery Clinics. 24(1): 27-40.
Fujiwara H., Shiozaki A., Konishi H., Kosuga T., Komatsu S., Ichikawa D., Okamoto K. & Otsuji E. 2015. Single-Port Mediastinoscopic Lymphadenectomy Along the Left Recurrent Laryngeal Nerve. The Annals of Thoracic Surgery. 100(3): 1115-1117.
Jin Y., Lu X., Xue L. & Zhao X. 2018. Retrospective Comparison of Two Minimally Invasive Esophagectomy in the Treatment of Esophageal Cancer: Pneumatic Mediastinoscopy Versus Thoracoscopy. Journal of Laparoendoscopic and Advanced Surgical Techniques and Videoscopy. 29(5): 638-642.
Oshikiri T., Takiguchi G., Miura S., Takase N., Hasegawa H., Yamamoto M., Kanaji S., Yamashita K., Matsuda Y., Matsuda T., Nakamura T., Suzuki S. & Kakeji Y. 2018. Current status of minimally invasive esophagectomy for esophageal cancer: Is it truly less invasive? Annals Gastroenterological Surgery. 3(2): 138-145.
Ranu H., Evans J., Sheth A. & Madden P.B. 2010. Removal of Long-Term Tracheal Stents with Excellent Tracheal Healing. The Annals of Thoracic Surgery. 89(2): 598-599.
Raske M., Weisse C. & Berent A.C. 2018. Immediate, short-, and long-term changes in tracheal stent diameter, length, and positioning after placement in dogs with tracheal collapse syndrome. Journal of Veterinary Internal Medicine. 32(2): 782-791.
Shrager J.B. 2010. Mediastinoscopy: still the gold standard. The Annals of Thoracic Surgery. 89(6): 2084-2089.
Suematsu M., Suematsu H., Minamoto T., Machida N., Hirao D. & Fujiki M. 2019. Long-term outcomes of 54 dogs with tracheal collapse treated with a continuous extraluminal tracheal prosthesis. Veterinary Surgery. 48(5): 825-834.
Tappin S.W. 2016. Canine tracheal collapse. Journal of Small Animal Practice. 57(1): 9-17.
Tinga S., Mankin K.M.T., Peycke L.E. & Cohen N.D. 2015. Comparison of outcome after use of extra-luminal rings and intra-luminal stents for treatment of tracheal collapse in dogs. Veterinary Surgery. 44(7): 858-865.
Weisse C., Berent A., Violette N., McDougall R. & Lamb K. 2019. Short-, intermediate-, and long-term results for endoluminal stent placement in dogs with tracheal collapse. Journal of the American Veterinary Medical Association. 254(3): 380-392.
Venissac N., Pop D. & Mouroux J. 2009. Video-assisted mediastinoscopy as a therapeutic tool. Surgical Endoscopy. 23(11): 2466-2472.
Violette N.P., Weisse C., Berent A.C. & Lamb K.E. 2019. Correlations among tracheal dimensions, tracheal stent dimensions, and major complications after endoluminal stenting of tracheal collapse syndrome in dogs. Journal of Veterinary Internal Medicine. 33(5): 2209-2216.
Zhu S., Yu S. & Liu F. 2020. Combined single-port transmediastinal and laparoscopic access with CO2 insufflation for esophageal resection: a case report on a canine model. AME Case Report. 4: 6.
How to Cite
This journal provides open access to all of its content on the principle that making research freely available to the public supports a greater global exchange of knowledge. Such access is associated with increased readership and increased citation of an author's work. For more information on this approach, see the Public Knowledge Project and Directory of Open Access Journals.
We define open access journals as journals that use a funding model that does not charge readers or their institutions for access. From the BOAI definition of "open access" we take the right of users to "read, download, copy, distribute, print, search, or link to the full texts of these articles" as mandatory for a journal to be included in the directory.
La Red y Portal Iberoamericano de Revistas Científicas de Veterinaria de Libre Acceso reúne a las principales publicaciones científicas editadas en España, Portugal, Latino América y otros países del ámbito latino