図１〜図３で盲腸まで造影されているので大量のガストログラフィンが注入されている．肝内ガスは辺縁から2cm以内まで達し門脈内ガスである．図９〜図１６の▲は小腸の壁内気腫であり，小腸壊死または高度の虚血状態を示している可能性が極めて高い．図９でIVCが虚脱し扁平となっており，高度の循環血液量不足状態である．図１７の△は1スライスだけでは壁内気腫かどうか判断が困難である．結腸の固形便周囲にはこのように線状のガスが存在することがあり，慎重な読影を要する．手術でTreitz靱帯から130cmの部位からＳ状結腸直腸移行部までが大量壊死に陥っていた．直腸癌が発見され，癌病変を含めて切除された．図１と図２１の↑が癌病変．この症例も強い脱水によるNOMIの可能性が高い．脱水の原因は大量のガストログラフィン（2倍に薄めても浸透圧は細胞外液の3倍）注入が原因と思われる（下記文献）．

参考症例（SMA塞栓症・小腸壊死）：心房細動のある84歳男性．10時間前に腹痛が突然出現し近医受診，様子観察されていたが，次第に増強したので紹介来院した．体温：37.7℃，下腹部に圧痛と反跳痛があるが筋性防御は認めない．

図１と図２の肝内ガスは門脈内ガスである．図３〜図１３の▲は壁内気腫，図１３〜図１６の白矢印はSMV分枝内ガスで，壁内ガスを認めなくてもその領域の腸管壊死を示唆する．図６からSMAが造影効果を欠き，SMA塞栓症による大量の小腸壊死である．図４のIVCが虚脱しており，高度の脱水が小腸壊死を助長している可能性が高い．図６の△は腎梗塞であろう．手術でTreitz靱帯から40cmと盲腸から20cmだけがviableで，他の全小腸の大量壊死を認めた．

文献考察：ガストログラフィン
Ann Surg. 2002 Jul;236(1):1-6.
Therapeutic value of gastrografin in adhesive small bowel obstruction after unsuccessful conservative treatment: a prospective randomized trial.
Choi HK, Chu KW, Law WL.

OBJECTIVE: To assess the therapeutic value of Gastrografin in the management of adhesive small bowel obstruction after unsuccessful conservative treatment. SUMMARY BACKGROUND DATA: Gastrografin is a hyperosmolar water-soluble contrast medium. Besides its predictive value for the need for surgery, there is probably a therapeutic role of this contrast medium in adhesive small bowel obstruction. METHODS: Patients with clinical evidence of adhesive small bowel obstruction were given trial conservative treatment unless there was suspicion of strangulation. Those who responded in the initial 48 hours had conservative treatment continued. Patients showing no clinical and radiologic improvement in the initial 48 hours were randomized to undergo either Gastrografin meal and follow-through study or surgery. Contrast that appeared in the large bowel within 24 hours was regarded as a partial obstruction, and conservative treatment was continued. Patients in whom contrast failed to reach the large bowel within 24 hours were considered to have complete obstruction, and laparotomy was performed. For patients who had conservative treatment for more than 48 hours with or without Gastrografin, surgery was performed when there was no continuing improvement. RESULTS: One hundred twenty-four patients with a total of 139 episodes of adhesive obstruction were included. Three patients underwent surgery soon after admission for suspected bowel strangulation. Strangulating obstruction was confirmed in two patients. One hundred one obstructive episodes showed improvement in the initial 48 hours and conservative treatment was continued. Only one patient required surgical treatment subsequently after conservative treatment for 6 days. Thirty-five patients showed no improvement within 48 hours. Nineteen patients were randomized to undergo Gastrografin meal and follow-through study and 16 patients to surgery. Gastrografin study revealed partial obstruction in 14 patients. Obstruction resolved subsequently in all of them after a mean of 41 hours. The other five patients underwent laparotomy because the contrast study showed complete obstruction. The use of Gastrografin significantly reduced the need for surgery by 74%. There was no complication that could be attributed to the use of Gastrografin. No strangulation of bowel occurred in either group. CONCLUSIONS: The use of Gastrografin in adhesive small bowel obstruction is safe and reduces the need for surgery when conservative treatment fails.PMID: 12131078（full text）
追記：ガストログラフィンの浸透圧は1900mOsm/Lで，細胞外液の6倍も高い．そのために腸管内に注入すると腸管壁から腸管内へ水分が移行し，閉塞部の浮腫を軽減させ単純閉塞の治療に有効である．潤滑油的性状も閉塞物の通過を容易にする．筆者私見：大量に注入するときは脱水に気をつけるべきである．