Identification of the site of severe colon bleeding by technetium-labeled red-cell scan.

In cases of severe colon bleeding, it is more important to know the site than the cause, in case surgery is required. Technetium-labeled red-cell scan (TLRCS) is known to identify the site of bleeding at the rate of 0.1 ml per minute or more. The aim of this retrospective study was to see whether TLRCS was a reliable indicator of the site of severe colon bleeding. A retrospective study was made of patients investigated in this way for acute, severe colon bleeding at St. Vincent's Hospital, Melbourne, from 1984 to 1988 (five years). TLRCS identified the site of bleeding in less than half of the cases but correctly identified the site in all nine patients in whom bleeding was so severe as to require emergency surgery, avoiding total colectomy in eight cases.