How long do prepared epidural solutions remain sterile?

The purpose of this study is to determine whether prepared epidural solutions remain sterile when refrigerated prior to use. The sterility of all epidural solutions prepared by an outpatient pharmacy of a tertiary level cancer facility was tested both at the time of preparation and after 14 days of refrigeration. Over a seven-month interval, we found no incidence of epidural solution colonization in 84 submitted samples prepared for four patients. All four patients had good relief of pain with ambulatory epidural infusion, and none developed clinical evidence of infection. We conclude that selected ambulatory patients with severe cancer pain, who are managed in the home environment with permanent epidural catheters, can use preservative-free epidural solutions that have been prepared with the sterile technique and stored in a standard domestic refrigerator for up to 14 days.