【作者】 廖晓斌；

【导师】 杨和平；

【作者基本信息】 第三军医大学 ， 内科学， 2008， 硕士

【摘要】 肺气肿是呼吸科一种常见疾病,对重度肺气肿伴或不伴有肺大疱患者,常规内科治疗仅能缓解症状,并不能阻断或逆转疾病的发展。外科肺减容术(Lung volume reduction surgery,LVRS)已显示对部分重度肺气肿患者,该治疗能提高患者的活动耐量和生活质量。然而LVRS也存在着风险,美国肺气肿治疗实验(NETT,National Emphysema Treatment Trial)指出,LVRS在对重度肺气肿患者的治疗中存在较高的死亡率(16% ,术后30天),即使除外高危患者,也存在明显的并发症和早期5%的死亡率。因而限制了LVRS的临床应用。于是需要一种更加安全的肺减容治疗方法,经支气管镜肺减容术(BLVR)有望成为这样一种选择。BLVR是不依赖外科手术,经支气管镜向过度充气的气肿性肺段内放入装置或药物以阻塞气道,使靶段肺丧失功能并萎陷,从而减少过度充气,缓解患者症状。目前国内外研究的装置和技术包括:单向支气管内活瓣、支气管封堵术、支气管开窗术等方法,其目的都是获得LVRS的益处,而无LVRS的手术创伤、风险及长期的康复过程。从目前的研究结果可以看出,单向支气管内活瓣适用于以上叶病变为主的不均一型肺气肿患者,支气管开窗术可能更适合均一型肺气肿患者。支气管封堵术目前还处于动物实验阶段,因而这项生物工程技术能否用于临床还不清楚,从目前的研究结果分析,它有可能对于上述两种类型的肺气肿患者均适用。支气管封堵术是经支气管镜将与生物相适的溶液注入靶段肺内,使其灶性肺不张并纤维化,形成瘢痕组织,达到肺减容目的。目前该方法仅在动物实验阶段,未见临床实验报道。国外Ingenito等人报道了动物实验,结果证实该方法能达到肺减容目的,并预测BLVR在临床应用中存在潜在的优势。本课题从研究应用支气管封堵液经支气管镜肺减容术的可行性及方法入手,观察支气管镜下犬肺形态,探索支气管封堵液的组成,探索经支气管镜肺减容术的操作技术,观察肺减容效果,探讨该方法的可行性、安全性,进一步为BLVR的临床实验提供可靠的实验依据。本课题主要包括以下内容:(一)经支气管镜肺形态学动物实验研究,为支气管镜肺减容术的动物实验提供基础数据1.观察实验犬术前、麻醉后、术中、术后一般情况(心率、呼吸频率、经皮血氧饱和度),以判断犬能否耐受支气管镜操作。2.支气管镜下观察实验犬肺形态,以判断犬是否适合支气管镜相关实验。3.观察实验犬肺的解剖,与支气管镜下肺形态观察结果比较,了解两者结果是否一致。(二)应用四环素经支气管镜肺减容术的动物实验研究1.探索经支气管镜向实验犬靶段肺内注入四环素的技术和方法。2.采用影像学(CT,术前及术后4w、8w、12w)和组织病理学方法(HE染色和组织免疫化学,术后12w)检测靶段肺组织情况。(三)应用组织封闭剂经支气管镜肺减容术的动物实验研究1.观测组织封闭剂的黏附性和生物相容性。2.探索经支气管镜向实验犬靶段肺内注入组织封闭剂的技术和方法。3.采用影像学(CT,术前及术后1h、4w、8w),组织病理学方法(HE染色和组织免疫化学,术后8w)检测靶段肺组织情况。主要结果1.术中所有操作过程顺利,未发现技术操作上的困难,所有实验犬均耐受此手术,无动物死亡,术后无明显并发症。2.支气管镜检查发现犬的气管较粗且结构总体上与人相似,适合支气管镜相关实验。3.术后第12w影像学、尸检及病理(HE染色和组织免疫化学)结果证实,应用四环素经支气管镜肺减容术实验中的8只实验犬靶段肺均形成瘢痕组织,达到肺减容的目的,无并发症发生,但术中和术后实验犬出现咳嗽等肺部刺激症状,说明四环素对靶段肺组织有刺激损伤。4.选用医用生物蛋白胶和0.1%左旋多聚赖氨酸作为组织封闭剂,具有良好的黏附性和生物相容性。5.术后第8w影像学、尸检及病理(HE染色和组织免疫化学)结果证实,应用组织封闭剂经支气管镜肺减容术实验中的8只实验犬靶段肺均形成瘢痕组织,达到肺减容的目的,无并发症出现,术后实验犬仅出现短期轻微咳嗽,说明组织封闭剂对肺部刺激损伤小。6.应用组织封闭剂行BLVR优于四环素,因为四环素是通过刺激靶段肺组织,诱发局部炎症反应,使其肺不张并纤维化,形成瘢痕组织,而组织封闭剂依靠良好的黏附性和生物相容性,对靶段肺的机械性封堵,使其丧失通气功能,逐渐萎缩,并发生组织重塑,局部胶原沉着,成纤维细胞和单核细胞聚集,形成瘢痕组织。故四环素对靶段肺组织有明显的刺激损伤,而组织封闭剂则小,更适合用于BLVR。结论一、经支气管镜肺减容术操作容易,创伤小,并发症少,可用于肺减容治疗。二、选用医用生物蛋白胶和0.1%左旋多聚赖氨酸作为组织封闭剂,具有良好的黏附性和生物相容性,可作为BLVR的材料。三、应用组织封闭剂经支气管镜肺减容术,是自身瘢痕组织替代肺组织,达到肺减容目的,此法可用于肺减容治疗。更多还原

【Abstract】 Emphysema is 4a debilitating lung disease continuing to be a major source of morbidity and mortality in the developed countries. Estimates suggest that as many as two million people are affected in the United States. Lung volume reduction surgery (LVRS) can relieve dyspnea in their COPD patients by correcting the overinflation of the chest by surgically removing lung tissue.Patients with advanced chronic obstructive pulmonary disease (COPD) continue to experience exertional breathlessness despite optimum medical therapy. In selected patients, lung volume reduction surgery (LVRS) has been shown to improve exercise capacity and quality of life . LVRS, however, is not without risk. In particular, the National Emphysema Treatment Trial (NETT) found an excess mortality (16% at 30 days) in patients with the most severe disease. Even when highrisk patients were excluded, surgical volume reduction has been associated with significant morbidity and an early mortality rate of about 5% .For this reason, there is a need for safer alternatives. Bronchoscopic lung volume reduction (BLVR) has the potential to become such an alternative. BLVR involves placing a device to obstruct the airway(s) leading to the most hyperinflated, emphysematous parts of the lung. The rationale for this approach is that endobronchial obstruction should cause these areas to collapse and thus, by reducing hyperinflation, alleviate symptoms without recourse to surgery.Devices and techniques under study include one-way bronchial valves inserted via fiberoptic bronchoscopy to promote atelectasis in emphysematous lung, promotion of focal atelectasis and fibrosis by bronchoscopic injection of polymers into emphysematous regions of lung, bronchopulmonary fenestrations to enhance expiratory flow, and thoracoscopic plication or compression of emphysematous lung. The goal of all of these procedures is to replicate the benefit of LVRS without the trauma, risks, and extended recovery of open LVRS. Refinement and application of these techniques will allow patients with emphysema and their physicians and surgeons to choose from a number of viable options for lung volume reduction.It may prove to be the existing case that valve insertion will be the appropriate therapy when there is heterogeneous disease and a target lobe can be identified. In homogeneous disease, with intralobar collateral ventilation being more likely, the airway bypass approach may prove to be preferable. Only animal data about bronchoscopic injection of polymers are available at present and it remains unclear whether it will be possible to apply this technique to humans. It is possible that this technique could be used in both types disease.The approach of bronchoscopic injection of polymers has been to find tissue engineering approaches that will produce lung volume reduction by causing scarring in target areas of the lung . Only animal data are available at present and it remains unclear whether it will be possible to apply this technique to humans. Ingenito et al. suggested collapsing target regions of the lungs using a procedure similar to bronchoalveolar lavage. The lavage involves controlled removal of bronchial epithelial lining cells with a washout solution and the deployment of a fibrin hydrogel. In a sheep model of emphysema this procedure achieved scar tissue formation, which replaced hyperinflated lung, reduced overall lung volume, and improved respiratory function safely and consistently.In our study, we observe the lung shape of crossbreed dogs, investigates the possibility of lung volume reduction with bronchoscope, explore the method and technique of BLVR, observe the effect of bronchoscopic lung volume reduction using fibrin-based glue,investigate the possibility and safe, offer experimental evidence of the minimally invasive techniques for the treatment of emphysema.The main contents of our study are as follows:1. To observe the lung shape of crossbreed dogs and investigate the possibility of lung volume reduction with brobronchoscope1) To investigate general state of health,at baseline, at operation of BLVR,at recovery after BLVR, including heart rate, respiratory rate, oxygen saturation.2) To observe the lung shape of crossbreed dogs including the length of trachea by brobronchoscope.3) To observe the dissection of lung after autopsy and compare with the lung shape observed by brobronchoscope.2. Animal study on bronchoscopic lung volume reduction using tetracycline1) To explore the method and technique of injecting tetracycline into treated sites by bronchoscope.2) To detected target lung by roentgenographic examination and histopathological methods at baseline,at 4w、8w and 12w postoperation respectively, and the present of TypeⅠcollagen,TypeⅡcollagen .3. Animal study on bronchoscopic lung volume reduction using tissue sealant.1) To observe the glutinosity and biocompatibility of tissue sealant.2) To explore the method and technique of injecting tissue sealant into treated sites by bronchoscope.3) To detected target lung by roentgenographic examination and histopathological methods at baseline,at 1h、4w and 8w postoperation respectively, and the present of TypeⅠcollagen,TypeⅡcollagen .Main results1. Procedure of operation was successful without technic difficulty, there were not dead animals, and complications did not happen.2. The lung shape of crossbreed dogs observed by brobronchoscope suggested that crossbreed dog was suitable for the operation of fibrobronchoscope.3. Serial CT scans, Autopsy and Microscopic examination to target lung performed 12w after BLVR using tetracycline, showed scar tissue substitute target lung and complications did not happen. Obviously and persistent cough happened after BLVR in the dogs explained that tetracycline were stimulant .4. Fibrin glue and 0.1% poly-l-lysine are choosed as tissue sealant injecting into treated sites, and were found satisfactory glutinosity and biocompatibility.5. Serial CT scans, Autopsy and Microscopic examination to target lung performed 8w after BLVR using tissue sealant, showed scar tissue substitute target lung and complications did not happen. Obviously and persistent cough did not happened after BLVR in the dogs explained that tissue sealant were mild.6. Tissue sealant was more suitable than tetracycline in BLVR. Because scar formation depend on satisfactory glutinosity and biocompatibility of tissue sealant in BLVR using tissue sealant, and scar formation was by inflammation in BLVR using tetracycline, the injury suffered from tetracycline was visible.conclusion:1. Operative procedure through BLVR is easy, trauma is little, complications are few, and this method will be used in lung volume reduction.2. Fibrin glue and 0.1% poly-l-lysine are choosed as tissue sealant because of it,s satisfactory glutinosity and biocompatibility.3. BLVR using tissue sealant demonstrates it can reduce lung volume by promoting localized fibroblast proliferation, collagen synthesis, and scar formation achieved,so it provides an effective, safer alternative to LVRS.更多还原