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.
ObjectiveTo perfect the surgical process that trachea could be reconstructed by nickel-titanium (Ni-Ti) alloy stent wrapped with autologous pericardium, and to evaluate the effectiveness and observe the complications. MethodsIn the experiment, twelve healthy Bama suckling pigs with weight of 18-25 kg were selected. The pericardium was harvested to cover the Ni-Ti alloy stent. The compound artificial trachea was used to reconstruct long-segmental (6 cm) trachea defect. The effectiveness, complications, the properties, and growth rate of the new mucosa of the artificial trachea lumen were observed. ResultsOf 12 pigs, 2 died soon because of hemorrhage and infection, respectively; 7 died at 2-4 months after operation because of hyperplasia at the middle section and blockage of phlegm plug; 3 survived after 42 weeks postoperatively, but accompanied with dyspnea symptom. At 1, 2, 3, 4, and 5 months after operation, the average crawl length of the new trachea mucosa was 1, 3, 5, 7, and 10 mm, respectively; the occurrence rates of anastomotic stenosis were 0 (0/10), 0 (0/9), 0 (0/4), 33.3% (1/3), and 33.3% (1/3) respectively; and the occurrence rates of scar hyperplasia in the middle of lumen were 20% (2/10), 66.7% (6/9), 75.0% (3/4), 66.7% (2/3), and 100% (3/3), respectively. At 7 months postoperatively, the bronchoscopy examination showed that the scar in central part of artificial trachea had the trends of stagnation, softening, and narrowing, and respiratory symptom had the trend of slight ease. Hyperplasia tissue could be found in central part of artificial trachea by autopsy and was verified to be fiber cells and necrotic tissue by pathology examination. ConclusionNi-Ti alloy stent with autologous pericardium can insure that the reconstructed tracheal lumen is unobstructed, and support the trachea epithelium regeneration; the main factors of the death of the experimental animals are the lumen hyperplasia of the artificial trachea and the blockage of the secondary phlegm plug.