Abstract 490: Acute Superior Mesenteric Artery Occlusion Presenting as Strangulated Inguinal Hernia
An 85yo woman presented with diffused colicky abdominal pain and vomiting for 12hr. Patient still had bowel movement and passed flatus. Patient was otherwise healthy without past medical or surgical history, and taking no medications. PE: no distress, afebrile, vitals are stable. Cardiopulmonary exam only revealed tachycardia; Abdomen: soft, non-tender, no distension, bowel sounds hyperactive; there was an 8[[Unable to Display Character: ]]6 cm irreducible, firm but non-tender right inguinal hernia. Labs: leukocytosis, bicarbonate 20. CT abdomen with oral contrast suggested small bowel obstruction secondary to right inguinal hernia. The hernia was then reduced manually. Post the reduction patient had one foul smell watery bowel movement.
However, patient deteriorated quickly. Repeat labs: bicarbonate 8, anion gap 23, lactic acid 11, ABG: 7.01/29/246/7/99%. EKG: A-fib with tachycardia. Patient’s blood pressure dropped necessitating IV fluid and vasopressor support. Strangulated hernia with septic shock was suspected and emergency laparotomy was performed. Ascending, transverse and descending colon past the splenic curve were found necroses with foul-smelling turbid fluid intraperitoneally; the small bowel was minimally dilated with a kink 25cm beyond the ileocelcal valve with evidence of previous incarceration. Subtotal colectomy and partial small bowel resection with ileostomy was performed. Pathology confirmed terminal ileum and colonic gangrene; recent mesentery venous thrombi. Despite appropriate therapy, patient continued to be in septic shock and developed multiple organ failure, a stroke, and then brain death.
Acute mesenteric ischemia (AMI) is a rare abdominal emergency with high mortality, which could be caused by direct strangulation of the SMA by the inguinal hernia (Tiwary SK et al 2008) or thromoboembolism, e.g., emboli from A-fib, septic emboli, local thrombosis. Since there is no evidence that the incarcerated portion of small bowel had necrosis, this case is mostly likely caused by the paroxysmal A-fib-derived emboli. Due to the lack of typical clinical expression, a high index of suspicion is essential for prompt diagnosis. CT angiography is the current cornerstones for diagnosis of AMI, so treatment can be initiated expeditiously.
- © 2013 by American Heart Association, Inc.