胃ESDによる偶発症の現状とその対策―剝離深度の重要性と手技の工夫

The Current Status and Management of Complications from Gastric ESD―Safety Procedures and the Importance of the Depth of Dissection

要旨　ESDにおける主な偶発症は出血と穿孔である．いずれも術中に発生する場合と術後遅発性のものとがある．術中穿孔は速やかなクリップ閉鎖による保存治療が可能で確実かつその後の処置の妨げにならないようスペースを作った後に行う．術中出血はESDの能率に影響し，成否を分ける．出血の原因となる粘膜下層の血管パターンは前庭部，体部小彎，体部前後壁（内側縦斜走筋群分布領域）の3群に大別され部位別に手順，剝離深度を設定することが攻略のカギである．ITナイフを用いる場合もアタッチメントで視野を確保しForcedあるいはSwift凝固による剝離（凝固モードトリミング）を併用することで出血の少ない処置が可能になった．遅発性穿孔は過通電による全層の凝固壊死が原因と考えられる．面積をもって筋層が脱落するため外科的対応を要する．術後狭窄に対する拡張術は穿孔も来しうるので注意しなければならない．後出血は前庭部や体部小彎に集中し占拠部位の要因が大きい．

　The main complications due to ESD are bleeding and perforation. Both of these have intra-operative and post-operative delayed consequences. Intra-operative perforation can be readily and conservatively treated by clipping, which is performed leaving sufficient space to enable subsequent treatment. Intra-operative bleeding can affect the efficiency and consequence of ESD. Blood vessels of the submucosal layer which account for bleeding are distributed broadly into 3 regions : the antrum, the lesser curvature of the stomach and the anterior and posterior wall of the stomach (area of distribution of the medial longitudinal oblique muscle), so the setting of the procedure and the depth of dissection according to regions are key points. In the case of using the IT knife, the field of view is maintained by an attachment and combined dissection by Forced or Swift coagulation (coagulation mode trimming) has enabled the reduction of bleeding. It is considered that delayed perforation is due to coagulation necrosis of whole layers due to over stimulation by electric current. It requires surgical treatment because the muscle layer which is extensive in area comes off. We must pay careful attention to dilatation of post-operative stenosis because it may adhere and cause perforation. Post-operative bleeding occurs frequently in the regions of the antrum and the lesser curvature of the stomach and it is related strongly to occupied regions.