Epidural analgesia—experience of 5628 patients in a large teaching hospital derived through audit

A prospective audit of 5628 surgical patients was conducted to determine the success, failure and complication rates associated with postoperative epidural analgesia. The majority of patients received infusions of bupivacaine 0.1% with hydromorphone 20 μg/cm³. However, elderly and frail patients received plain bupivacaine 0.1% or bupivacaine 0.1% with fentanyl 2 μg/cm³. Postoperatively, epidural infusions were selected, adjusted or terminated as indicated. Termination of epidural analgesia was defined as either success, if the infusion was continued until there was no further need for epidural analgesia, or failure, if the infusion was discontinued prematurely due to problems with the catheter or treatment that could not be controlled through intervention. Twenty-two percent of patients had their epidural catheter removed prematurely due to either technical (catheter) or treatment (medication) problems that could not be resolved. Technical problems with the catheter caused 807 failures (14% of all patients). Almost 70% of the technical failures (N=554) were due to catheter dislodgement. Treatment problems resulted in 451 failures (8% of all patients). The majority of treatment failures were due to inadequate analgesia despite functioning catheters. This audit has proved useful in maintaining standards of care and in identifying problems with postoperative epidural therapy that still need improvement. It allows a balanced assessment of the value of this treatment in the setting of a large teaching hospital and is the largest reported series of postoperative epidural hydromorphone analgesia.