OBJECTIVETo investigate the possibility of tracheas transplantation by wrapping it in a muscle flap.

METHODSWith a dog model, a number of tracheas were separately wrapped in the unilateral sternocephalic muscle flap and the bilateral sternohyoid-sternothyroid muscle flap, and placed in the original site. The tracheas autografting was used as a control. The viability was evaluated by the examination of fiberoptic bronchoscopy, histopathology and microangiography, the measurement of tracheal mucosal blood flow and the calculation of survival rate and percentage of patency.

RESULTSThe submucosal blood flow of the transplanted tracheas was detected in the unilateral sternocephalic muscle flap group and the bilateral sternohyoid-sternothyroid muscle flap group 1 week after the surgery and gradually reached the level close to the normal in 4 weeks, while the vascular ingrowth was also shown from the wrapped muscle flap into the transplanted tracheas by using a microangiography technique. The histopathological examination demonstrated that the structure of the transplanted tracheas was quite same as the original one and its inner surface was also covered with pseudostratified columnar ciliary epithelia. However, in the control group, the mucous membranes turned black one week after the transplantation and all dogs died from the graft necrosis.

CONCLUSIONThe tracheas wrapped in a muscular flap could survive well for a long time.