Postoperative analgesia is an important challenge in the perioperative period, as postoperative pain and discomfort can affect postoperative recovery. At our hospital, epidural anesthesia is the first choice for postoperative analgesia in laparotomy, whereas intravenous patient-controlled analgesia (iv- PCA) is the main choice in laparoscopic surgery. Laparoscopic surgery is generally said to be minimally invasive and to cause less postoperative wound pain; however, in practice, there are some patients experiencing inadequate postoperative analgesia. In a pilot study conducted at our hospital, 20 patients who returned to the High Care Unit (HCU) after undergoing laparoscopic surgery with general anesthesia had the mean Numerical Rating Scale (NRS) pain score at rest of 4 to 5 (moderate pain) during the night to the following morning despite therapeutic intervention. The disposable PCA device used in our hospital delivers a continuous flow rate of 2 mL/h (fixed), a bolus dose of 1 mL/20 min (fixed), and a total volume of 100 mL. Fentanyl to be filled in the infusion device is diluted to 10-15 μg/mL in consideration of the adverse drug reactions of respiratory depression, nausea, and vomiting. The continuous dose of fentanyl is 20-30 μg/h, and the bolus dose is 10-15 μg/dose (lockout time of 20 minutes and maximum hourly dose of 30-45 μg/3 mL). Although this device is effective in many cases, it is often observed that when the patient's blood concentration of fentanyl is far from the minimum effective analgesic concentration at that point, the bolus dose does not reach the effective analgesic concentration and sufficient analgesic effect cannot be obtained. Dexmedetomidine which we focused on in this study is familiar to anesthesiologists. It has been used for many years for sedation in ICUs and operating rooms because it provides sedation without affecting respiration. It has been reported that the use of dexmedetomidine as an adjuvant to general anesthesia during surgery reduces the doses of intraoperative anesthetics and analgesics required and those of postoperative analgesics. Dexmedetomidine has recently attracted attention as one of the drugs that play a role in multimodal postoperative analgesia and opioid sparing anesthesia. It is expected to have potential to act as an adjunct to postoperative analgesia. Although the analgesic effect of dexmedetomidine is not as strong as that of opioids, postoperative analgesia in laparoscopic surgery may be improved by using dexmedetomidine in combination with opioids, NSAIDs, and acetaminophen.