Effect of Ketamine on the Quality of Anesthesia and Postoperative Analgesia in Epidural Anesthesia

PurposeTo investigate the additional effects of ketamine to the epidural anesthesia over quality of intraoperative anesthesia and postoperative analgesia.MethodsSixty adult patients, aged 20–70 years with an American Society of Anesthesiologists physical status of I-III (ASA I-III) who were scheduled for total hip arthroplasty were enrolled. A 18-gauge epidural needle from the L4-5 space in addition to bupivacaine 75 mg; fentanyl 100 mcg was delivered in Group BF, ketamine 30 mg in Group BK, and fentanyl 100 μg plus ketamine 30 mg in Group BKF. Onset time of sensory block, start time of surgery, maximal sensory block level, time to two-segment regression, length of anesthesia, motor block level, quality of anesthesia, and patient satisfaction were determined. At the end of the operation, analgesia was achieved by patient-controlled analgesia method. Time to first analgesic requirement, morphine consumption at 24 hours, number of requests for additional analgesic, and the amount of delivered bolus solution, were noted.ResultsThere was no statistically significant difference between the groups with regard to onset time of sensory block and length of surgery. Start time of surgery was significantly shorter in Group BKF; and time to two-segment regression, length of anesthesia, and time to first analgesic requirement were significantly longer in Group BF. Morphine consumption at 24 hours, number of requests for additional analgesic, and the amount of delivered analgesic bolus were minimal in Group BKF.ConclusionEpidural ketamine shortened the start time of surgery by reducing the onset time of block and elevating the maximal block level.