自体肺组织修补胸内食管缺损(英文)

Repairing intrathoracic esophageal defect with autologous pulmonary tissue in dogs

背景:食管切除术需要行食管替代修补,在常规腹腔脏器不能使用的情况下,临床上缺乏有效的食管替代修补物。目的:探寻自体带血运的肺组织瓣修补胸内食管不规则缺损的新方法,为临床应用提供动物实验依据。设计:观察性动物实验。单位:中国医科大学附属第二医院胸外科。材料:实验于2003-01/2004-06在中国医科大学附属第二医院动物实验室完成。选用健康成年杂种犬14只,体质量12￣18kg,雌雄不限,由中国医科大学附属第二医院动物实验室提供(许可证号:SYXK辽2003-0019)。方法:14只实验犬麻醉后行右肺中叶游离,结扎切断右肺中叶支气管,不损伤肺动静脉,制成肺组织瓣作为修补物。将实验犬的胸内食管行全层侧壁切除,缺损长4cm,环1/2￣2/3管腔。将肺组织瓣覆盖于食管缺损处,与食管断面相吻合。术后3d静脉输液维持营养,术后第7天经口进全流食,2周过渡为半流食。观察实验犬能否正常经口进食及其存活情况。术后2,4,6,8,10周各处死2只实验犬,观察食管修补处愈合情况,并行光镜、透射电镜、食管钡餐及内镜检查。主要观察指标:①术后实验犬的存活和进食情况。②实验犬食管修补处的愈合情况。结果:14只实验犬存活11只,其余3只犬于术后1周内死亡。①术后实验犬的存活和进食情况:实验犬11例存活,最长存活时间超过170周;存活犬均能正常经口进食。②实验犬食管修补处的愈合情况:术后2周,光镜下见替代物管腔表面有胶原及炎性渗出物,两端近吻合口处见少许上皮形成,为一两层鳞状上皮细胞,排列欠规则。术后4￣6周,光镜下见替代物管腔表面为复层鳞状上皮细胞,分3￣5层。术后8￣10周,肉眼观察食管缺损处完全被具有正常外观的食管黏膜所覆盖。光镜示食管替代物的管腔表面可见6￣8层复层鳞状上皮细胞覆盖。肺组织瓣的病理改变主要为肺泡萎陷,肺组织纤维化,可见散在的炎性细胞。透射电镜见食管缺损处肺组织瓣的表面有新生的分层的鳞状上皮细胞。术后8周食管钡餐检查发现钡剂顺利通过食管缺损处。术后10周食管内镜见食管缺损处管腔内完全覆盖着正常外观的食管黏膜。结论:应用自体肺组织瓣修补胸内食管不规则缺损可作为一种简便易行的新方法。

BACKGROUND： Esophageal replacement or reconstruction should be performed after esophageal resection. There are still no suitable substitutes for esophagus if the conventional esophageal substitutes cannot be used. OBJECTIVE： To investigate the feasibility of applying a pulmonary tissue with vascular pedicle to repair the intrathoracic esophageal defect. DESIGN ： A prospective animal investigation SETTING： Department of Thoracic Surgery, Second Hospital Affiliated to China Medical University MATERIALS： This trial was carried out in the laboratory of Department of Thoracic Surgery, Second Hospital Affiliated to China Medical University during January 2003 to June 2004. Fourteen adult mongrel dogs of either gender, with body mass of 12 to 18 kg, were provided by Animal Room, Second Hospital Affiliated to China Medical University （License No. SYXK （Liao） 2003-0019）, METHODS： Of 14 anesthetized dogs, the middle lobe of right lung was dissected and its right middle lobar bronchus was ligated without damaging pulmonary and bronchial vessels in order to make pulmonary flap. A part of full-layer intrathoracic esophageal wall was resected, which was 4 cm long and 1/2 to 2/3 circled esophageal wall. The defect was patched by pulmonary tissue with vascular pedicle which was inosculated with esophageal cross section. On the 3rd day after operation, intravenous transfusion was performed to maintain nutrition. On the 7^th day after operation, the dogs were given oral liquid soft food gradually 2 weeks after the operation. The access to the food and the survival of dogs were observed. Every 2 dogs were sacrificed respectively at the 2^nd, 4^th, 6^th, 8^th and 10^th postoperative weeks. To observe the healing of esophageal defect, light microscope, transmission electron microscope, esophagography and endoscope were used in this study. MAIN OUTCOME MEASURES： ① Survival situation and access to food of dogs after operation. ② The healing of esophageal defect of dogs. RESULTS： Three of fourteen dogs died within one week after operation. Eleven dogs survived. ① The survival and access to food of experimental dogs after operation： One dog was alive without problems for more than 170 weeks. The living dogs could be fed orally on the 7^th day after operation. ② The healing at esophageal defect of experimental dogs： At the 2^nd week after operation, the esophageal defect was covered with collagen layer and inflammatory exudation. A little epithelization was observerad at free edge of the anastomosis, which was 1 to 2 layers of stratified squamous epithelium cells. At the 4^th to 6^th weeks after operation, the internal surface of the defect was covered with 3 to 5 layers of stratified epithelium cells. At the 8^th to 10^th weeks after operation, the luminal surface of the defect was covered with 6 to 8 layers of stratified epithelium cells. The pathological changs of pulmonary flap mainly included pulmonary alveoli atelectasis and pulmonary fibrosis, and some inflammatory cells without infective focus were observed. In the transmission electron microscope examination, newborn stratified squamous epithelium cells were. found on the surface of pulmonary tissue flap at esophageal defect. CONCLUSION ： It is feasible to repair the partial irregular intrathoracic esophageal defect with the autologous pulmonary flap in dogs.