術前の弾道評価が重要であった胸腹部移行帯の銃創の1例(A case of gunshot wound of the thoracoabdominal transition zone that required ballistic evaluation)

要旨 56歳の男性。自ら38口径の拳銃で左胸を1発撃ち受傷した。左前胸部に射入口と左背部に射出口があり，focused assessment with sonography for traumaで心嚢液，左胸水を認めたことより銃弾は左前胸部から心臓，肺を損傷し背部から体外へ射出されたと考えられた。しかし，hybrid ERにてCTを撮像したところ心損傷，肺損傷に加えて，腹部管腔臓器損傷を疑う微小なfree airの散在と左第11肋骨に骨折を認めた。銃弾は心嚢から横隔膜を経て腹腔内に至り，左第11肋骨で反射して，左胸腔内に至り体外へ射出されたと診断できた。開胸，開腹により心縫合，左下葉部分切除での止血と胃穿孔部縫合閉鎖，横隔膜縫合修復を行い，術後19日に退院した。銃創，とくに胸腹部移行帯において弾道評価による損傷臓器の推定は重要である。弾道評価においては射入口と射出口に加えて骨折部に注目することで，弾道をより正確に推測し，損傷臓器を推測することが可能であった。 ABSTRACT A 56–year–old male shot himself in the left chest with a handgun and was injured. Focused assessment with sonography for trauma showed pericardial and left pleural effusions, suggesting that the bullet had entered the left anterior chest, damaged the heart and left lung, and exited the body through the left back. However, computed tomography (CT) imaging revealed, in addition to the cardiac and pulmonary injuries, small free air bubbles and left 11th rib fracture, suggesting gastrointestinal tract injuries. We deduced that the bullet entered the abdominal cavity from the pericardial sac through the diaphragm, ricocheted off the left 11th rib, entered the left thoracic cavity, and was ejected out of the body. The patient was discharged from the hospital 19 days after open chest and abdominal surgery with cardiac suturing, hemostasis achievement by left lower lobe partial resection, gastric perforation suture closure, and diaphragmatic suture repair. Damaged organs must be identified via the ballistic evaluation of gunshot wounds, especially in the thoracoabdominal transition zone. It is important to focus on the fracture area for ballistic evaluation.