Annals of Long Term Care

Case Presentation
Mrs. S, an 81-year-old woman who had previously resided in an assisted living facility, is living in a nursing home for rehabilitation following a hip fracture, which occurred several weeks ago after slipping on ice. Past medical history includes congestive heart failure (ejection fraction = 0.25), hypertension, hypercholesterolemia, mild chronic renal insufficiency (creatinine 3.4 mg/dL), and early-stage dementia. Her medications include furosemide, lisinopril, atorvastatin, isosorbide dinitrate, and donepezil.

For several weeks prior to falling, Mrs. S had been experiencing postprandial abdominal cramping, and thus had reduced her food intake, resulting in a 5-pound weight loss during this time. She underwent an open reduction internal fixation and had no postoperative complications. She has done well with her rehabilitation and is ambulating without difficulty.

After eating, she again is experiencing abdominal cramping, which the nursing staff attributes to gas. She is scheduled to return home in a few days.

The night before discharge, she is found in her bed, vomiting and writhing in pain, pointing to the peri-umbilical area. Vital signs include a temperature of 99 degrees F, blood pressure 90/70 mmHg, respirations 32, and pulse rate 115.

Mrs. S is transferred to the local emergency department, where the abdominal examination reveals mild distension, diminished bowel sounds, minimal diffuse tenderness, with rebound tenderness. Her white blood cell count is elevated at 18,000 with 10% bands. The BUN is elevated at 54, and the creatinine 3.9 mg/dL. An urgent radiological procedure is considered, but because of renal insufficiency, an exploratory laparotomy is performed

Discussion
Intestinal ischemia (mesenteric ischemia) is a result of reduced blood flow to the bowel, with resulting injury to the bowel from hypoxemia, with associated nutrient deficiency.

The splanchnic circulation supplies the small bowel and colon via the superior mesenteric, inferior mesenteric, and hypogastric arteries. Because there is extensive collateralization between these arterial supplies, ischemic disease will only occur if there has been significant compromise in two of the three main arterial trunks. Further protection against ischemic injury results from a network of intramural submucosal vessels, which help to preserve parts of the bowel even when the extramural arterial supply has been interrupted.¹ During an ischemic event, the intramural blood supply is redistributed to help preserve the mucosa.²

Intestinal ischemia can be acute or chronic, involving an artery, arteriole, vein, or venule, and can be located in the small or large bowel. The condition can be further categorized as occlusive (embolic or thrombotic) and non-occlusive (ischemic). Mrs. S most likely suffered an acute ischemic event in a background of chronic mesenteric insufficiency.

Chronic mesenteric insufficiency (intestinal angina) is almost always a result of decreased blood flow due to atherosclerosis of the proximal mesenteric arteries. At least two of the major splanchnic vessels are occluded in over 90% of patients, and all three in over 50%.³ Patients typically present with postprandial abdominal pain. At first, the pain may be minimal, usually after a large meal, and can last for several hours. Over time, the pain can become more severe and incapacitating, peaking and receding over several hours, and results in fear of eating because of the anticipation of pain. Steatorrhea occurs in about 50% of patients. Ultimately, most patients experience a significant weight loss.⁴

Some patients with acute superior mesenteric artery occlusion may have an ileus, but no rectal bleeding, and thus the diagnosis may be delayed, especially in patients in intensive care units or with other medical problems.