Experimental Study Of Nano-Biomaterials Artificial Trachea

OBJECTIVE:The reconstruction and anastomoses after tracheal resection has been a consistent problem, it is necessary to use the tracheal prosthesis. Even after decades of research, most of the existing artificial tracheal prosthesis were used in the stage of animal experiments, clinical applications were less, There also remain a variety of postoperative complications. To find better materials for artificial tracheal prosthesis become a urgent problem. The ideal tracheal prosthesis should have a good biological performance and biomechanical properties. The experimental used nano-carbon fiber as the main material to weave into a tube-like, and used carboxyethyl chitosan/nano-hydroxyapatite (NCECS/n-HA) to coat on the wall, madding into a kind of new nano-biomaterials artificial trachea prosthesis. After determining the biomechanical performance and conducting animal experiments, we investigate the possibility of the trachea to be an ideal artificial tracheal prosthesis.METHODS:(1) Nano-carbon fiber was woven into a tube-like,(length30-50mm,inter diameter8-10mm). coated the carboxyethyl chitosan-hydroxyapatite composite (NCECS/n-HA) on the wall,madding into the artificial trachea prosthesis. The TY8000servo-handle tension test machine was used to measure the radial pedestal and longitudinal tensile mechanical properties of the artificial trachea prosthesis, and compared with mechanical properties of rabbit cervical trachea.(2)The new nano-biomaterials tracheal prosthesis were embeded in the neck of6rabbits for4weeks, HE staining, immunohistochemistry and fluorescence staining were used to observe the vascular regeneration of the tissue surrounding the artificial trachea.(3)4weeks after the embedding of the artificial trachea, the artificial trachea prosthesis with muscle and vascular pedicle was implanted to the cervical trachea of the rabbits. Their living conditions were observed and recorded,The rabbits were killed after2,4,6weeks. The tracheal prosthesis and surrounding tissue was harvested, generally observing whether there was deformation and tracheal collapse, whether the lumen was smooth, Histological examination was used to measure epithelial lining inside the lumen.RESULTS:(1)The mechanical properties of nano-biomaterials artificial trachea was in line with the requirements of artificial trachea. the radial pedestal and longitudinal tensile mechanical properties of the artificial trachea prosthesis was better than the rabbits (P<0.01)(2) HE staining, immunohistochemistry and fluorescence staining demonstrated the neovascularization in the surrounding tissue of tracheal prosthesis.(3) All rabbits tolerated the surgical procedure well and perioperative mortality did not occur. After cervical tracheal replacement, the experimental rabbits survived in good condition. In the experimental group,6#rabbit died at30d for postoperative respiratory secretions obstruction. The remaining animals survived well, and at42d after operation,they were euthanized.The artificial trachea were dislodged,and dissection revealed that artificial trachea were tightly wrapped around by the tissue,. Vessels were seen around the graft and apparently growing toward the graft surface. The graft still maintain good flexibility, without collapse or deformation. New mucosal epithelium can be seen from anastomosis along to the the central of the artificial trachea, but the crawling distance was short, the length of pipe is not covered completely. The control group all animals died within20days for postoperative complications such as anastomotic leakage, obstruction of airway secretions.CONCLUTION:Tracheal prosthesis made of nano biomaterials with good mechanical properties and biological properties, is a kind of porous artificial trachea prosthesis. This study has taken two steps, the first step was embedding and the second step was tracheal replacement with vascular pedicle. This method of experiment can prevent the airway infections and other complications which the porous artificial trachea prosthesis can occur. By detecting the surrounding tissue of tracheal prosthesis, neovascularization can be found, which provided a rich blood supply to the artificial trachea. Compared with the control group, the experimental animals had a better blood supply, which was more effective to avoid the artificial tracheal fistula. This created a rich blood supply, closed, smooth internal environment. The nano-biomaterials artificial trachea prosthesis was in line with the law of development of artificial trachea and provided a new idea for the study of artificial trachea.