Randomized multicentre trial of oral bowel preparation and antimicrobials for elective colorectal operations.

A study of 120 patients undergoing elective colorectal operations has investigated the effect of adding oral neomycin and metronidazole to bowel preparation in a double-blind randomized controlled trial. Comparisons have also been made between a standard mechanical preparation and the use of an elemental diet. The addition of neomycin and metronidazole to bowel preparation significantly reduced the rate of wound sepsis (P less than 0.01), septicaemia (P less than 0.02) and anastomotic dehiscence (P less than 0.02); anaerobic infections were abolished and there was a significant reduction in the incidence of aerobic Gram-negative infections. Elemental diets were shown to have no advantage over mechanical preparation.