Transplantation of tracheal autografts: is a two-stage procedure necessary?

Tracheal autotransplantation has been shown to be a reliable technique for repairing the hemilaryngectomy defect that includes the hemicricoid cartilage and results from resection of unilateral laryngeal cancer with significant subglottic extension. The technique involves a two-stage procedure of cervical tracheal revascularization by wrapping the trachea in a vascularized radial forearm flap and subsequent tracheal transplantation on a newly created vascular pedicle consisting of the radial artery and vein (1, 2).

To experimentally (rabbits) investigate if a one-stage tracheal revascularization and transplantation procedure could be a viable option.

Tracheal patch autografts (1.5 cm x 1 cm) were excised and reimplanted at the anterior cervical trachea with four different patterns of vascular supply: group I: tracheal patch wrapped with vascularized fascia 14 days before excision of the patch (two-stage procedure); group II: tracheal patch wrapped with vascularized fascia at the time of patch excision; group III: tracheal patch without tissue wrapping; and group IV: tracheal patch wrapped with a sheet of Gore-Tex after reimplantation. After orthotopical reimplantation, the patches showed decreasing vascular contacts from group I to group IV. The patches were evaluated morphologically at the moment the animal became dyspnoeic or two weeks after reimplantation in asymptomatic animals.

Group I patches fully preserved their viability (median percentage mucosal viability of 100%). Autografts in group II and III showed varying degrees of necrosis and graft take with a median percentage graft viability of 59 and 69% respectively. All group IV tracheal patches showed full thickness necrosis over the majority of their surface area (median percentage graft viability of 10%).

Fascia enwrapped tracheal autografts show reliable revascularization through the intercartilaginous ligaments only when a 2 stage revascularization technique is used.