Occult gastrointestinal bleeding was defined as continued bleeding in spite of a normal series of roentgenograms of the upper part of the gastrointestinal tract, barium enema, and sigmoidoscopy. Twenty-six such patients were treated. A thorough systematic evaluation, including gastroscopy, colonoscopy, visceral angiography, and isotopic scanning, was done preoperatively. Using colonoscopy and arteriography, nearly 60% of the bleeding sites were identified. Seventy-six percent of the lesions identified were in the terminal part of the ileum or the ascending colon. Exploratory laparotomy should be performed for life-threatening hemorrhage or as a diagnostic test only after a thorough preoperative evaluation. If results of a complete preoperative evaluation including arteriography were normal, then the likelihood of finding a discrete cause of bleeding at laparotomy was high (80%). A systematic evaluation and diligence of both physician and patient in localizing the site of bleeding are essential.
Richardson JD, McInnis WD, Ramos R, Aust JB. Occult Gastrointestinal BleedingAn Evaluation of Available Diagnostic Methods. Arch Surg. 1975;110(5):661-665. doi:10.1001/archsurg.1975.01360110207036