重症僧帽弁逆流症による心原性ショックに対し局所麻酔下でV-A ECMOを確立し麻酔導入を行った1症例

Induction of Veno-Arterial Extracorporeal Membrane Oxygenation under Local Anesthesia followed by General Anesthesia of a Patient in Severe Cardiogenic Shock due to Mitral Regurgitation：A Case Report

要旨

　80歳，女性。重症僧帽弁逆流症（mitral regurgitation：MR）に伴う心不全を来し，内科的治療への反応が乏しく，緊急僧帽弁置換術の方針となった。米国心血管インターベンション学会（Society for Cardiovascular Angiography and Interventions：SCAI）の心原性ショックの重症度分類（SCAI shock分類）ステージD以上と評価し，少量の麻酔薬の投与のみで致死的な循環不全を来す可能性が高いと判断した。

　各診療科と協議し，局所麻酔下で静脈脱血-動脈送血体外式膜型人工肺（veno-arterial extracorporeal membrane oxygenation：V-A ECMO）を導入した後に，麻酔薬の投与および気管挿管を行い，致死的な循環不全を来すことなく麻酔導入を行うことができた1症例を経験した。

　Emergent mitral valve replacement was scheduled for a 80-year-old Japanese woman with congestive heart failure associated with severe mitral regurgitation and refractory to medical therapy. We assessed her condition as severe cardiogenic shock, stage D or higher, based on the Society for Cardiovascular Angiography and Intervention（SCAI）shock classification. An induction of general anesthesia was thus considered highly likely to cause circulatory collapse. After a multidisciplinary discussion, veno-arterial extracorporeal membrane oxygenation（V-A ECMO）was first applied with the patient under local anesthesia；general anesthesia was then induced and tracheal intubation was safely performed. In cases of severe cardiogenic shock, a prior induction of V-A ECMO under local anesthesia may avoid the fatal circulatory collapse associated with the induction of general anesthesia.