S3380 Atherosclerotic Small Bowel Ischemia Causing Intestinal Obstruction and Volvulus

Abstract

Introduction: Obstructions are the most common events requiring surgical intervention in the small intestine. Several factors can cause an obstruction, with adhesions from previous surgeries being most common. It is rare for the obstruction to be caused by volvulus of the small bowel, and increasingly more rare for that volvulus to be caused by ischemia due to atherosclerosis. Presented herein is a unique case of small bowel obstruction due to volvulus of the small bowel that resulted from severe bowel ischemia. Case Description/Methods: The case discusses the medical and surgical management of a 70-year-old man who presented to the emergency department with abdominal pain. After a thorough history, physical exam, and diagnostic testing, the patient was diagnosed with small bowel obstruction due to volvulus, secondary to atherosclerotic ischemia of the small intestine, and rushed to surgery. After the surgical intervention and hospital stay, the patient made a complete recovery and was asymptomatic at follow-up appointments. Discussion: Small bowel obstructions occur mostly due to adhesions from prior surgeries. It is exceedingly rare that they may occur due to volvulus. This case is unique in that the inciting event was significant small bowel ischemia, likely from uncontrolled hyperlipidemia and atherosclerosis as evidenced by the CT findings of a severely atherosclerotic abdominal aorta. The ischemia then made way for the necrotic segment of the small bowel to twist upon its mesentery and cause a closed loop obstruction and further compromise of the blood supply to the small intestine. The presentation of a volvulus in the small intestine is not as easily recognizable on radiographs as a sigmoid and cecal volvulus. The classic “birds beak” phenomenon characteristic of any volvulus on contrast enhanced plain film was not seen in this case. Imaging was consistent with a small bowel obstruction, but the etiology was unclear until an exploratory laparotomy was performed. It is likely that this patient had a chronic underlying process of mesenteric ischemia before presenting with this volvulus that was never diagnosed. Ischemia must be considered as a differential or possibly as an underlying factor for future management when working up a patient for bowel obstruction. Swift intervention in this scenario likely prevented outcomes such as perforation and severe hemodynamic instability. This patient would benefit from cholesterol lowering medications and possibly endovascular repair to prevent future recurrence.