Noninvasive detection of experimental intestinal ischemia.

Acute intestinal &hernia is associated with a mortality of more than 80% [2, 3, 14, 181. Periods of &hernia greater than 6 to 12 hr often commit the surgeon to an extensive resection of gangrenous bowel from which few of these critically ill patients can recover [ 141. Delay in diagnosis is recognized as the major factor contributing to the high morbidity associated with this condition [3]. Clearly, early detection is essential for the successful treatment of acute intestinal ischemia. No methods are currently available for the rapid, noninvasive screening of patients at high risk for intestinal ischemia before substantial infarction has occurred. Findings by physical examination are not diagnostic, and when present, often indicate that the diagnosis has been made too late [ 14, 181. Other means of evaluation, including visceral arteriography [3], serum chemistries [4, 6, lo], radiologic appearance [ 161, dye dilution [7], intestinal radionuclide imaging [ 1, 11, 12, 131, and intestinal ~xylose absorption [ 151, have not proved to be accurate and specific in the early detection of intestinal ischemia. Recent investigations into the metabolic requirements of the small intestine have demonstrated that glutamine is extracted from the mesenteric bloodstream as a primary metabolic substrate for cells of the small intestinal