Tissue engineering trachea is an artificial trachea with biological activity, which is constructed in vitro by using tissue engineered principle and technology, and is a tracheal prosthesis for replacing large circumferential defect of the trachea. The course of its construction is as follows. First, seeding cells are cultured and expanded in vitro. Then they are collected, counted and seeded onto the biomaterial scaffold of tissue consistent and biodegradation. Finally, the biomaterial-cells construction is implanted into bio-reaction device or one’s subcutaneous layer. The tissue engineering trachea could be constructed after cultured certain times. Compared with other artificial trachea, the tissue engineering trachea has more advantages, such as nonimmunogenicity, no side-effects related to foreign graft materials, and biologic activity. This will bring some hope to look for an appropriate graft material. However, the study about it is still faced with some difficult problems, such as vascularized trachea, culturing in vitro, and prevention of infection in trachea prosthesia. So there will be long time for tissue engineering trachea to apply clinical tracheal transplantation successfully. This assay has reviewed the study about tissue engineering trachea from three sides——the source of seeding cells, the research about biomaterial scaffold, and the construction of tissue engineering trachea.
Objective To construct a new composite artificial trachea and to investigate the feasibility of trachea repair and reconstruction with the new composite artificial trachea transplantation in dogs. Methods The basic skeleton of the new composite artificial trachea was polytetrafluoroethylene vascular prosthesis linked with titanium rings at both ends. Dualmesh was sutured on titanium rings. Sixteen dogs, weighing (14.9 ± 2.0) kg, female or male, were selected. The 5 cm cervical trachea was resected to prepare the cervical trachea defect model. The trachea repair and reconstruction was performed with the new composite artificial trachea. Then fiberoptic bronchoscope examination, CT scan and three-dimensinal reconstruction were conducted at immediate, 1 month, and 6 months after operation. Gross observation and histological examination were conducted at 14 months to evaluate the repair and reconstruction efficacy. Results No dog died during operation of trachea reconstruction. One dog died of dyspnea at 37, 41, 55, 66, 140, and 274 days respectively because of anastomotic dehiscence and artificial trachea displacement; the other 10 dogs survived until 14 months. The fiberoptic bronchoscope examination, CT scan and three-dimensinal reconstruction showed that artificial tracheas were all in good location without twisting at immediate after operation; mild stenosis occurred and anastomoses had slight granulation in 6 dogs at 1 month; severe stenosis developed and anastomosis had more granulation in 1 dog and the other dogs were well alive without anastomotic stenosis at 6 months. At 14 months, gross observation revealed that outer surface of the artificial trachea were encapsulated by fibrous connective tissue in all of 10 dogs. Histological examination showed inflammatory infiltration and hyperplasia of fibrous tissue and no epithelium growth on the inner wall of the artificial trachea. Conclusion The new composite artificial trachea can be used to repair and reconstruct defect of the trachea for a short-term. Anastomotic infection and dehiscence are major complications and problems affecting long survival.
Tracheal stents are often used to maintain the patency of the trachea and bronchia in patients suffering from central airway lesions. Metallic tracheal stents are now widely used in the clinical setting, but these types of stents can cause many intractable material-related complications. Biodegradable tracheal stents are made of biodegradable polymer materials with good mechanical strength for maintaining the patency of the lesion segment during a certain period of time, and then they can be gradually degraded into harmless products in human body. Compared with conventional metallic tracheal stent, biodegradable tracheal stents have a good prospect in clinic. In this article, we review the choice of biodegradable tracheal stent materials, experimental progress in biodegradable tracheal stent as well as the challenges we are facing.
Objective To study the surgical treatment of tracheal and main bronchial tumors. Methods We retrospectively analyzed the clinical data of 30 patients with tracheal and main bronchial tumors treated in Shengjing Hospital of China Medical University from January 2000 to December 2015. There were 12 males and 18 females with the age ranging from 22 to 80 years. Results Ten patients were treated with enucleation, 12 patients tracheal tumor resection and end-to-end anastomosis, 1 patient window resection, 1 patient wedge resection, 5 patients tumor resection and tracheal reconstruction by using pulmonary tissue flap with alloy stent and 1 patient left pneumonectomy. One patient died of sudden massive hemoptysis 26 d after operation. Intraoperative complications were found in 2 patients. Others had a good recovery after operation. Patients were followed up for 11 months to 14 years. Eight patients were followed up less than 5 years postoperatively, one patient died of sudden massive hemoptysis 14 months after operation, while others survived; 21 patients were followed up more than 5 years and 5 patients were lost to follow-up. Conclusion Surgical resection is recommended for tracheal and main bronchial tumors. Patients with small benign tumor may choose local tracheal resection; tracheal segmental resection and end-to-end anastomosis is the most common surgical treatment. Patients with more than half of the whole length of tracheal defects or in the risk of anastomotic ischemic necrosis may be suggested to receive tracheal reconstruction.
Objective To investigate the impacts of cytokines （interleukin-4，IL-4；tumor necrosis factor-α，TNF-α） and medications of bronchial asthma （dexamethasone，aminophylline，salbutamol） on the activity of histamine N-methyltransferase（HMT） in tracheal epithelial cells.Methods BEAS-2B bronchial epithelial cells were cultured and treated with different concentration of TNF-α, IL-4, dexamethasone, salbutamol and aminophylline respectively. The activity of HMT in BEAS-2B cells was determined by high performance liquid chromatography.Results The activity of HMT in tracheal epithelial cells was (50±7) pmol?min-1?mg pro-1.TNF-α and IL-4 lowered the activity of HMT significantly at the concentration equal to or higher than 1 ng/mL and 5 ng/mL respectively，and reached the maximum inhibitory effect at the level of 10 ng/mL.Dexamethasone and aminophylline could ameliorate distinctly the inhibitory effect of TNF-α on the activity of HMT, while salbutamol had no significant inhibitory effect.Conclusions TNF-α and IL-4 exert the lowering effect on the activity of HMT，which would be one important cause of airway hyperreactivity.Glucocorticoids and theophyllines are administered to treat asthma partly due to its relieving mechanism of TNF-α negative effects on HMT.
Abstract： Objective To investigate the methods of diagnosis and treatment for early and late cheobronchial rupture, in order to improve the understanding of this disease. Methods We retrospectively analyzed the records of 19 patients treated for traumatic tracheobronchial rupture in our hospital between October 1988 and August 2010. There were 9 males and 10 females with a median age of 28 years (ranged from 8 to 48 years). We analyzed the clinical characteristics of the disease, including clinical presentation, and the results of chest Xrays, computed tomography（CT）, and fibrobronchoscopy. There were 2 cases of tracheal repair, 1 case of tracheostomy, 8 cases of bronchial reconstruction, 7 cases of bronchial repair, and 1 case of pneumonectomy. Results Seventeen patients were cured by operation and 2 patients died of multiple organ failure. Blood oxygen saturation resumed normal in most patients after operation (9680%±159% vs. 8840%±390%，Plt;0.01). Postoperative followup time was ranged from 3 to 24 months, and no tracheobronchial stenosis was observed and no patients needed stent or dilatation for treatment. Conclusion The diagnosis of tracheobronchial rupture depends on history of trauma, chest Xray, CT and fibrobronchoscopy results. Surgical treatments should be based on the tracheobronchial reconstruction or repair, and the clinical outcome is satisfying.
OBJECTIVE: To compare the effect of several types of rib rings with intercostal muscles for the replacement of trachea in thorax. METHODS: The surface layer of the third rib of dogs were ripped off and curved into triangular, quadrilateral and polygonal form. These three types of rib rings with intercostal muscles were used to replace a segment of trachea in thorax. RESULTS: The stability of triangular rib ring was very well, but stricture of ring were often happened because of its smaller internal diameter. These stability of quadrilateral rib ring was the worst. The polygonal rib ring presented the biggest diameter and good stability compared to the other two kinds of rings. If silicone tube was supplemented in the polygonal rib ring, the quality of artificial trachea was excellent. CONCLUSION: The rib rings with intercostal muscles are successfully used for replacing the defect of trachea in canine thorax. The polygonal rib rings have the best quality in the three types of rib ring for tracheal replacement.
Objective To summarize the clinical experiences in treating primary tracheal tumors by surgery, so as to improve the results of surgical treatment. Methods The clinical data concerning 22 surgically treated patients were retrospectively analyzed. Four patients tumor were benign and eighteen cases’s tumor was malignant. Tracheal resections and end to end anastomosis were performed in 14 cases, carinal resection was performed in 4 cases, lateral tracheal wall resection was performed in 1 case, local scrape were performed in 2 cases, tumor was resected transfiberoptic bronchoscopy in 1 case. Tracheal resectable length was from 2.0cm to 5.2cm，and the average resectable length was 3.8cm in operation. Results 17 cases had been misdiagnosised ( 77.3%) in outpatient department. It was easy to be misdiagnosised as asthma. One case died of respiratory failure after operation in 30 days. The complication rate was 31.8%, complications consist of pneumonia in 4 cases, anastomosis leakage in 1 case and chylothorax in 2 cases. Anastomosis stenosis was found in 3 cases, the syndromes were improved after treatment.Twenty cases were followed up from 1 month to 8 years. Four cases with benign tumors were still alive. Among 16 cases with malignant tumors, 6 cases had survived more than 5 years， 3 cases died of brain, liver, bone metastasis of malignant tumors. Conclusion Surgical resection is the most effective treatment of tracheal tumors. Tracheal resection and reconstruction is the main choice of primary tracheal tumors treatment. Benign tumors can be resected conservatively. The reductions of operative complications are the key points of good surgical results. To know the characteristic of primary tracheal tumors well can reduce the misdiagnosis rate.
Objective To observe the effects of ambroxol injection on mucosal surface structure of trachea injured by intratracheal instillation of amikacin. Methods 280 Wistar rats were randomly divided into four groups( n = 70 in each group) , ie. a normal control group, a normal saline group( intratracheally instilled normal saline) , an amikacin group ( intratracheally instilled amikacin) , and an ambroxol group ( intratracheally instilled amikacin and ambroxol simultaneously) . At the time points of 2, 12, 24, 48, 72 hours six animals in each group were killed and the samples of 1/3 lower segment of trachea were collected and observed by scanning electron microscope. Endotracheal intubation were made on other 6 animals to collecte broncho-alveolar lavage fluid ( BALF) for leucocyte count. Results Compared with the normal control group, elevated leucocyte count was observed in all other groups, various grades of swelling of the cilia were revealed, followed by more or less cilia laid flat with adjacent cilia conglutinated. Then partial cell membrane on top of some cilia bulged out. In terms of injury, the normal saline group was the most mild, and the amikacin group was most serious with the highest leucocyte count. All the parameters were relieved in ambroxol group. Conclusions Intratracheal instillation of amikacin causes acute injury of the ultrastructure of mucosal surface cilia. Ambroxol can promote the recovery process and alleviate inflammation of airway.
Objective To investigate the efficacy and influential factors of interventional therapy for post-intubation tracheal stenosis. Methods The clinical data of 69 patients with tracheal stenosis after tracheal intubation in the First Affiliated Hospital of Guangzhou Medical University from February 2010 to March 2015 were retrospectively analyzed. The effects of interventional treatment for tracheal stenosis after intubation were evaluated by reviewing the medical records and telephone follow-up for more than 1 year. Multivariate logistic regression model was used to analyze the influential factors. Results The study recruited 69 patients with the median age of 44 years. After the interventional treatment, ATS dyspnea score decreased from (2.41±0.76) points to (0.65±0.62) points ( P<0.01), the diameter of airway lumen increased from (4.24±2.05)mm to (10.57±3.14)mm ( P<0.01). The short-term effective rate of interventional therapy was 92.8% (64/69) but the restenosis rate in 1 month, 3 months and 1 year after interventional treatment were 56.5%, 26.1% and 36.2%, respectively. Multivariate logistic regression analysis showed that diabetes (OR=2.819, 95%CI 1.973-4.062）, shortness of breath score >3 points (OR=13.816, 95%CI 5.848-32.641）, trachea stenosis diameter <4.5 mm (OR=7.482, 95%CI 4.015-13.943), tracheal stenosis grade ≥4 (OR=3.815, 95%CI 2.258-6.447), stenosis in the upper trachea (OR=5.173, 95%CI 3.218-8.316) were risk factors of interventional therapy for post-intubation tracheal stenosis. Conclusions The general efficacy of interventional treatment for tracheal stenosis after tracheal intubation is poor, and the recurrence rate is still high. The high degree of tracheal stenosis, diabetes mellitus and upper tracheal stenosis are important factors that affect the efficacy of respiratory interventional therapy.