IT is commonly assumed that colonic surgery is safer when the bowel is empty and reasonably free from pathogenic organisms. Indeed, the preparation of patients about to undergo colonic surgery by dietary restriction, colonic lavage and administration of poorly absorbed chemotherapeutic agents is practised in many hospitals.The first effective chemotherapeutic agents to be used for colonic sterilisation were the relatively non-absorbable sulphonamides (Garlock and Seley, 1939 ; Poth, 1947). The oral administration of streptomycin was later thought to have certain advantages in terms of potency and rapidity of effect, but these were soon offset by the discovery of emergent resistant organisms (Lockwood, 1949 ;Jawetz and Bierman, 1952). The subsequent use of oral chloramphenicol and aureomycin was also disappointing; they were absorbed, and their effect on the bowel flora proved unpredictable (Pulaski et a!., 1950).Oral neomycin was first used as an intestinal antiseptic in 1949, and its combinations with bacitracin and polymyxin have been considered to afford the most effective pre-operative bowel preparation yet achieved (Jawetz and Bierman, 1952 ; Poth, 1957).Whilst it is tempting to believe that the declining mortality and morbidity of colonic surgery during the 1940s was largely due to the advent of bowel sterilisation (Dixon and Benson, 1944 ;Pemberton et al., 1947), there has been some scepticism concerning the validity of such a contention (Lockwood, 1950), and in this respect it would certainly be naive to disregard the significance of the concomitant improvements in surgical techniques and anasthesia, and the fuller understanding of fluid balance and blood transfusion. Indeed, there has been surprisingly little comment on the specific contribution of the newer agents such as neomycin and bacitracin to the improved operative results, but the issue may have appeared unimportant from the relative absence of reports of untoward side effects following their use.The following case history, however, which records a fatal complication after pre-operative bowel preparation with neomycin and bacitracin, has given rise to some speculation regarding the rationale and advisability of the routine pre-operative use of these agents in colonic surgery. Case History.-W. B., female, aged 68 years, presented with intermittent painless hiematuria of six weeks' duration. Apart from a degree of hypertension (200-1 10 mm. Hg), clinical examination was unremarkable but investigations revealed an infiltrating carcinoma which involved most of the right wall of the bladder. After full assessment it was decided to treat her by total cystectomy and ureterocolic anastomosis. She was prepared for operation by dietary restriction and colonic washouts, and was given neomycin 500 mg. and bacitracin 30,000 units 6-hourly by mouth, during the 48 hours immediately before operation. The operation itself was uneventful and the estimated blood loss of 500 ml. was promptly replaced. Subsequent pathological examination of the specimen confirmed tha...
