Vascular-pedicled costal cartilage graft for the treatment of subglottic and upper tracheal stenosis

Reconstruction of tracheal wall defect with a mesh patch of nickel-titanium shape-memory alloy

OBJECTIVES

We explored the feasibility of reconstructing tracheal wall defects with a mesh patch fashioned from a nickel-titanium shape-memory alloy.

METHODS

A tracheal wall defect was first constructed surgically by resecting the anterior half of the tracheal wall between the second and sixth tracheal rings. The defect was reconstructed in 8 experimental animals by replacing the resected tracheal mucosa and tracheal cartilage with a pedicle skin flap, which was then enclosed in the mesh patch. In 4 control animals, only a pedicle skin flap with strap muscles was used in the reconstruction procedure. The performance of the animals was observed after surgery. At the end of the experiments, the reconstructed segment was harvested for anatomic evaluation.

RESULTS

In the experimental group, 1 animal died 5 days after the operation. Endoscopic and anatomic examination of the 7 animals that survived the observation period showed that the reconstructed trachea was stable, with sufficient airway space for breathing. All 4 control animals died after the operation. After observing successful completion of this operation in animals, we successfully used this method to repair a tracheal wall defect in a human victim of a traffic accident.

CONCLUSIONS

Tracheal defects can be successfully reconstructed by use of a mesh patch of nickel-titanium shape-memory alloy as an extraluminal stent--a method that avoids complications associated with intraluminal stents.

[Scared atrophy of the cervical part of trachea as an effect of prolongated intubation]

Tracheal intubation is presently one of the basic medical procedures. It is connected with many different complications. One of them is tracheal stenosis, which occurs in 6-21 percent of patients after intubation of the trachea. In contrast to this high frequency of tracheal stenosis we didn't find any publications about complete atrophy of a big part of trachea after prolongated intubation and we describe a first case of such complication. The reasons and the possibilities of treatment in such situation are discussed.

Tracheal replacements: part 1

In this review, we summarize the history of tracheal reconstruction and replacement as well as progress in current tracheal substitutes. In Part 1, we cover the historical highlights of grafts, flaps, tube construction, and tissue transplants and address the progress made in tracheal stenting as a means of temporary tracheal support. This is followed in Part 2 by an analysis of solid and porous tracheal prostheses in experimental and clinical trials. We conclude Part 2 with a summary of recent efforts toward generating a bioengineered trachea. Finally, we provide an algorithm on the spectrum of options available for tracheal replacement.

Formation of in vivo tissue engineered human hyaline cartilage in the shape of a trachea with internal support

OBJECTIVE

Treatment and management of congenital as well as post-traumatic trachea stenosis remains a challenge in pediatric surgery. The aim of this study was to reconstruct a trachea with human nasal septum chondrocytes by using the combination of biodegradable hydrogel and non-biodegradable high-density polyethylene (HDP) as the internal predetermined shape scaffold.

METHODS

Human nasal septum cartilage was harvested as excessive tissue after elective septoplasty and digested in 0.6% collagenase II. Chondrocytes were cultured in an equal volume mix of Ham's F12 medium and Dulbecco's modified eagle medium added with 10% fetal bovine serum and basic fibroblast growth factor. After two passages, the cultured chondrocytes were trypsinized and mixed with biodegradable hydrogel Pluronic F127. The chondrocytes-hydrogel admixture was then painted over the HDP as the internal support in a predetermined trachea shape. The composite was then implanted subcutaneously in athymic mice.

RESULTS

After 8 weeks of in vivo implantation, the tissue engineered trachea constructs were harvested. Macroscopic appearance of the tissue engineered trachea constructs demonstrated that the HDP were 80-90% covered with yellowish glistering cartilage like tissue without any sign of inflammation. The tissue engineered trachea cartilage consisted of evenly spaced lacunae embedded in basophilic matrix and stained red with Safranin-O staining denoting abundant proteoglycans production. Type II collagen gene which was expressed in native cartilage was highly expressed in this tissue engineered trachea cartilage.

CONCLUSION

We have successfully reconstructed a trachea in vivo with human nasal septum chondrocytes using HDP as the internal support. This construct has the advantage of bio-inert and strength in which both are important properties in tracheal reconstruction.