Esophageal replacement using cryopreserved tracheal graft

Esophageal replacement using artificial material is not a new concept. Prior experiences with prostheses, allografts and composite grafts have not proved particularly successful. The aim of this study is to investigate whether cryopreserved animal trachea is suitable for the replacement of the esophagus. In 12 beagle dogs a 6-cm-long segment of the cervical esophagus was removed, and was replaced with cryopreserved trachea, which had been stored for 21 days on -86 degrees C. The proximal and distal ends of the esophagus were joined together with the graft by simple continuous suture (Biosyn 3/0) and covered with the sternohyoid flap. Postoperatively 16 hematological parameters were measured. The dogs were planned to be euthanized at random on days 28, 42 and 56 after the operation. Tests for air leak were performed and the inner diameter of the graft was measured to detect shrinkage. The microscopic structure of the graft was analyzed using haematoxylin and eosin staining. There was no indication of insufficiency. Based on the air leak test the sutures withheld properly. The inner diameter of the graft narrowed from an average 19 mm (+/- 1 mm) to 15.8 mm (+/- 0.6 mm). In length, the graft shortened from an average 60 mm to 47 mm (+/- 3 mm). No feeding difficulty was observed. In two cases wound suppuration was found involving only the cutaneous and subcutaneous layers. Concerning the laboratory parameters, only the fibrinogen level and white blood cell count showed temporary although significant changes. Histology findings on the 56th day showed absolute integration of the trachea with the esophagus, with disintegration of the tracheal cartilages. Cryopreserved trachea seems to be suitable for the replacement of a 5-6-cm-long esophageal segment.