Sir,The benefits of thoracic epidural analgesia after abdominal surgeries are well established[1] but the safety and efficacy during the postoperative period is highly variable and depends on the nature of the drug, mode of administration, type of surgery, presence of co-morbidities, etc.We undertook a retrospective study over 22-month period in patients, who underwent major abdominal surgery and received thoracic epidural analgesia, to assess the safety and efficacy of thoracic epidural analgesia used for relief of acute post-operative pain and compare outcomes of continuous epidural infusion and intermittent epidural administration. All the patients who underwent major abdominal surgery with placement of thoracic epidural catheter between February 2009 and December 2010 were retrospectively analyzed. The epidural charts were screened to include only the patients who received uneventful thoracic epidural analgesia in the operating room and were likely to remain on epidural analgesia for a minimum of 3 days postoperatively and the catheter was unlikely to be removed before at least 2 days of analysis. A total of 101 patients were taken for analysis.The patients received 0.125% Bupivacaine in normal saline with fentanyl 2 mcg/ml either 8 hourly intermittent bolus or as continuous infusion during the postoperative period. The rate of infusion and the volume of epidural bolus during intermittent boluses were based upon the discretion of anesthetist depending on the hemodynamic status, severity of pain etc. The pain scores were recorded every 4 hourly on day 1 and 8 hourly on day 2 and day 3. Intravenous paracetamol or intramuscular diclofenac was used in the appropriate dosage as rescue analgesic whenever VAS > 3.The hemodynamic parameters were continuously monitored and recorded hourly on day 1 and 2 hourly on day 2 and 3. Results were expressed as mean ± SD or percentage as appropriate. Ordinal data were compared using the Chi-square test. The difference in the pain scores according to the continuous or intermittent epidural administration was detected by one-way ANOVA (analysis of variance).There was satisfactory analgesia after major abdominal surgery using thoracic epidural technique alone in 56% of the patients on day 1, 67% of patients on day 2 and 62% of patients on day 3 after surgery. More patients in the intermittent bolus required rescue analgesics (70.45% vs. 29.54%; P < 0.05) than the continuous infusion group. Hypotension was more common in the intermittent bolus than continuous infusion group only on day 1 but was not severe to discontinue epidural analgesia. The same effect has also been observed in a few studies[23] in different settings where the requirements of rescue analgesics for inadequate pain relief were more common with intermittent epidural analgesia.