Bacteriological Profile of Epidural Catheters.

The bacteriological profile of epidural catheters was studied in 88 patients. Skin swabs before catheterization and before removal of catheter with their controls were cultured in TSB Medium. The catheter hub, the portion at the skin puncture site and at the tip were cultured in TSB Medium. The 1cm of the catheter bit just before the tip was cultured in TGB medium for anaerobes.Both, the skin controls swabs and the anaerobic culture, were negative. From the remaining, 56 positive cultures were obtained. Staphylococcus epidermidis was the predominant organism in 52% followed by staphylococcus aureus 25%. The remaining 23% was shared by Acinetobacter, Pseudomonas, Klebsiella, and E. coli. All the positive cultures from skin prior to epidural catheterization had turned sterile by 48 hours, indicating continued bactericidal action of the disinfectant. The likely source of positive skin cultures at 48 hours is hair follicles.The catheter tip culture was positive in 9 specimen, none of which resulted in the formation of epidural abscess. In 3 cases the cultures of skin puncture site and the tip were identical indicating tracking-in of the organisms.