Intermittent versus continuous epidural infusion technique for post operative analgesia

Background and Aim: A consensus is yet to evolve over which of the two techniques, continuous epidural infusion or intermittent epidural bolus is better for post-op pain relief. The present study was undertaken to compare the efficacy of postoperative pain relief between continuous and bolus administrations of epidural bupivacaine and fentanyl solution. Material and Methods: The prospective, randomized study was conducted in 60 ASA I and ASA II patients of either sex, 20-50 years age scheduled for orthopedic lower limb surgery. Combined spinal epidural anaesthesia was administered to all the patients. Following an epidural loading dose of 10 ml of 0.0625% bupivacaine with fentanyl 1.5 μg ml-1 post-operatively, group I (n = 30) patients received intermittent bolus of 10 ml of 0.0625% bupivacaine with fentanyl 1.5 μg ml-1 at an hourly interval for 24 hours and group II (n = 30) patients received same drug combination through continuous epidural infusion technique at a rate of 10 ml hr-1 for 24 hours. Following variables were assessed during the study period of 24 hours: Pulse rate, blood pressure, respiratory rate, pulse oximetry (SpO2), pain score (VAS), pruritus score, sedation score, sensory block and motor block. All the parameters were analysed statistically by adopting appropriate statistical tests. Results: On comparison, pain scores were statistically not significant in both groups (p>0.05). When compared within the respective groups, variation in pain score, both at rest and on movement, from the baseline value (zero hours postoperatively) were statistically not significant at all the time intervals in both the groups (p>0.05). Fifteen patients in the group I and five patients in group II required rescue analgesia (p<0.05). Thirteen patients (46.6%) in group I and 19 patients (63.33%) in group II assessed pain relief as excellent at the end of 24 hours of epidural analgesia (p<0.05). No adverse effects were observed in any of the patients. Conclusion: Continuous epidural infusion of a combination of bupivacaine and fentanyl provides better postoperative analgesia requiring less rescue analgesia than intermittent epidural bolus technique.