We performed a prospective, randomized study in 55 ASA 1 to 3 women undergoing elective gynaecological surgery followed by postoperative epidural analgesia. We compared the incidence of bacterial colonization at the epidural exit site following catheter removal between a control group and an experimental group who received a chlorhexidine impregnated dressing (Biopatch, Johnson and Johnson, Arlington, TX, U.S.A.). Positive culture results were found in 11 of 27 (40.1%) patients in the control group compared with one of 29 (3.4%) patients whose epidural catheters were dressed with the Biopatch. We concluded that the Biopatch was effective in reducing bacterial colonization of the epidural catheter exit site.