Factors influencing the quality of postoperative epidural analgesia: an observational multicenter study

BACKGROUND: Epidural analgesia (EDA) is used widely for postoperative pain treatment. However, studies have reported a failure rate of EDA of up to 30%. We aimed to evaluate the quality of postoperative EDA in patients undergoing a laparotomy in five Norwegian hospitals. METHODS: This was a multicenter observational study in patients undergoing a laparotomy with epidural-based postoperative analgesia. Data were registered at three time points. Technical aspects, infusion rates, pain intensity, assessment procedures, side effects, and satisfaction of patients and health personnel were recorded. The use of other pain medications and coanalgesics was registered. RESULTS: Three hundred and seventeen patients were included. Pain control at rest was satisfactory in 89% of patients at 24 hours and in 91% at 48 hours. Pain control when coughing was satisfactory in 62% at 24 hours and in 59% at 48 hours. The spread of hypoesthesia was consistent for each individual patient but varied between patients. The hypoesthetic area was not associated with pain intensity, and the precision of the EDA insertion point was not associated with the pain score. Few side effects were reported. EDA was regarded as effective and functioning well by 64% of health personnel. CONCLUSION: EDA was an effective method for postoperative pain relief at rest but did not give sufficient pain relief during mobilization. The use of cold stimulation to assess the spread of EDA had limited value as a clinical indicator of the efficacy of postoperative pain control. Validated tools for the control of EDA quality are needed.