海藻酸钠凝胶黏膜下注射黏膜隆起效果的实验研究*

目的以生理盐水(NS)为对照,评估不同浓度的海藻酸钠(SA)溶液作为黏膜下注射液,用于内镜黏膜下剥离术(ESD)的可行性及优越性。方法 1在新鲜离体猪食管及猪胃的黏膜下,注入不同浓度的SA溶液及NS溶液,观察并测量各注射液所致黏膜隆起高度,及此高度随时间的变化情况;2在活体小猪的胃黏膜下注射SA溶液后,模拟进行ESD手术,观察SA溶液对ESD术的辅助作用。结果离体猪食管、胃实验中,注射相同体积SA溶液的实验组所致黏膜隆起高度明显高于注射NS的对照组。其中,食管黏膜下注射1%SA溶液与注射NS相比,差异有统计学意义(P0.01);胃黏膜下注射3%SA溶液维持黏膜隆起高度与注射NS相比,差异有统计学意义(P0.001)。活体小猪胃模拟ESD术的实验中,注射SA溶液可以明显地分离组织、隆起黏膜,且形成稳定的凝胶垫,促进术中快速剥离黏膜的同时保护下层组织。结论黏膜下注射SA溶液可以持久地维持黏膜隆起高度,有利于黏膜组织的剥离切除,且由于其黏性,可较好地在黏膜下形成保护屏障,并对创面起到一定的压迫止血作用,可减少ESD术中穿孔、出血等并发症的出现。因此,SA是可用于临床的较为理想的黏膜下注射液。

Experimental study on the elevation effect of sodium alginate as a submucosal injection solution*

Objective To evaluate the feasibilities and advantages of different concentrations of sodium alginate (SA) solutions as a submucosal injection solution for endoscopic submucosal dissection (ESD). Methods In vitro study, different concentrations of sodium alginate solutions and normal saline were injected into submucosal of resected porcine esophagus and stomach respectively, then observe and measure the heights of each injection induced mucosal elevations, and their changes over time. In vivo study, the mimic ESD were conducted in healthy pigs to evaluate the mucosal elevation effect and other assistant effects of sodium alginate as a submucosal injection solution. Results The elevation heights of the experiment groups injected with SA solutions were much higher than the control group injected with normal saline. Specially, the elevation created by 1 % SA in porcine esophagus was significantly higher than that of normal saline (P < 0.01) and the elevation created by 3 % SA was significantly higher than that of normal saline in porcine stomach (P < 0.001). In the mimic ESD experiment, mucosal elevation with clear margin occurred immediately after injection with SA solution. And the durable submucosal fluid cushion created by SA protected deeper tissues while facilitating ESD procedure. Conclusion The elevation heights created by SA solutions were greater and more durable than that created by normal saline, which were crucial for ESD. The viscosity property enabled SA to form a stable protective cushion and prevent bleeding by squeezing tissue around the wound, which may decrease perforation and bleeding rate during ESD procedure. Therefore, sodium alginate can be an ideal clinical submucosal injection solution.