EXOTIC CARE AT BEVS

Patient: Stumpy, 7-year-old male domestic Mallard Duck

Reason for visit: Intermittent dyspnea

Exam/Diagnostics: Stumpy was breathing normally on presentation but quickly developed respiratory distress when being restrained for examination. He was sedated and a brief physical exam was performed, which revealed no significant findings. Initial diagnostic testing included lateral and ventrodorsal full-body radiographic imaging, followed by lateral and ventrodorsal radiography of the head and neck. A lesion was present in the trachea at the level of C6, which was consistent with a complete 360° transverse tracheal rupture or, less likely, a disease process (neoplasia, infection, etc.) causing localized lysis of the tracheal rings. No subcutaneous emphysema or air leakage associated with the lesion. Gentle palpation of the area revealed an approximately 1 cm tracheal defect, with no crepitus or external evidence of trauma noted. 

A tentative diagnosis of a complete transverse tracheal rupture of unknown origin was made, with CT, tracheoscopy, or exploratory surgery being needed for confirmation.  

Treatment: After a discussion with the owner, immediate surgery to explore and correct the defect was pursued. Anesthesia was induced, Stumpy was carefully intubated, and an air sac cannula was placed in the left caudal thoracic air sac. The endotracheal tube was then removed and anesthesia was maintained through the air sac cannula. Although the trachea was clearly separated, the delicate adventitial layer around the trachea was intact. This thin layer of tissue was sufficient to prevent air leakage and the development of subcutaneous emphysema and allowed Stumpy to breathe normally when at rest. Other than being transected, the trachea appeared healthy, with no obvious, gross pathology noted. Additionally, there was no other evidence of trauma observed within the surgical field that may have been associated with the injury. The separated ends of the trachea were apposed with 6 simple interrupted sutures and the incision was closed. 

Outcome: A post-operative tracheoscopy was performed with a 2.7-mm rigid endoscope to assess the surgical repair. The trachea appeared well apposed and no significant narrowing or intraluminal debris was observed. Approximately 8 weeks after the surgical procedure, Stumpy was presented for re-examination. The owner reported that he had exhibited no further respiratory signs and was ‘‘completely back to normal.’’ No abnormalities were identified during the physical examination. Radiographic images and a tracheoscopy examination of the tracheal lumen performed when the bird was reassessed revealed only a small degree of narrowing at the anastomosis site with no accompanying signs of inflammation.