Application of a bioengineered composite neotrachea in a dog model

Surgical treatment of extensive tracheal lesions remains a major challenge because of lack of an ideal airway substitute that is well vascularized, rigid, and autologous. We describe a novel surgical technique of tracheal reconstruction using a combination of a polypropylene mesh material and anterior cervical myocutaneous flap in a dog model.

A 3.5-4 cm length of cervical trachea was resected in 16 dogs and replaced with a myocutaneous cervical neck flap wrapped around the plain polypropylene tube (group 1, n = 7) or wrapped around a composite of polypropylene tube with an implanted Z-type metallic-covered stent (group 2, n = 9). The cervical tracheal defect was repaired with the previously mentioned substitute that was directly sutured to the remaining tracheal ends. Dogs were followed up using bronchoscopy and x-rays and euthanized at predetermined times for histologic examination.

In group 1, four dogs died within 2 wk from respiratory failure with varying degrees of airway collapse and difficulties in expectoration. In group 2, eight dogs survived, whereas one died of anastomotic dehiscence 1 wk after surgery. Necropsy and histologic examination of the anastomotic sites revealed good healing tissue. Pathologic examination also revealed excellent healing of the squamous epithelium of the neotrachea and the columnar epithelium of the native tracheal mucosa.

The tissue compatibility of the polypropylene mesh material and anterior cervical myocutaneous skin flap makes this a promising therapeutic substitute for treatment of patients with extensive tracheal lesions.