Find the Adequate Dose of Nalbuphine for Laparoscopic Cholecystectomy

This study evaluate the adequate dose of mutonpain for laparoscopic cholecystectomy in the management of post operative pain. The investigators will randomize patients into three groups to compare the analgesia effects and side effects.

Nalbuphine is a FDA approved noncontrolled drug of opioid. And it had been applied for post operative pain for different surgeries, claiming that less nausea and vomiting with the same analgesic effect when comparing with morphine. However, several studies concerning post pain management usually used nalbuphine 0.15-0.3 mg/kg for laparoscopic cholecystectomy. If the analgesic effect of nalbuphine is similar with morphine, less nalbuphine injection could reduce the side effects of opioid. The investigators will randomize patients into three groups of different initial nalbuphine dose for post laparoscopic cholecystectomy surgical pain, and set patient control analgesia machine with nalbuphine for further pain management. If the pain or side effects of opioid were intolerable, the investigators will change pain medications into NSAIDs or other adequate medications to comfort the patient. The primary outcome were numerical rating pain score and consumption of nalbuphine. The secondary outcomes were nausea, vomiting, pruritus and satisfactory score, and if any other medications use.

The Numerical Pain Rating Scale is a subjective measure in which individuals rate their pain on an eleven-point numerical scale. The scale is composed of 0 (no pain at all) to 10 (worst imaginable pain). The investors will measure the pain score at rest state and upon movement state at post-operative 1 hour, 2 hours, 4 hours, 24 hours, 36 hours.

The investors will use patient control analgesia machine to calculate the time dependent dose of nalbuphine.

we will go to bed side and have an self-report episode of nausea at 1 hour, 2 hours, 4 hours, 24 hours, 36 hours post operation

we will go to bed side and have an self-report episode of vomiting at 1 hour, 2 hours, 4 hours, 24 hours, 36 hours post operation

The net promoter score is a subjective measure in which individuals rate their satisfactory on an ten-point numerical scale. The scale is composed of 1 to 10. We will measure the net promoter score at the end of the study

if the patient use other pain medication on request of poor pain control or poor tolerant of the side effects of nalbuphine

Inclusion Criteria: patient accept laparoscopic cholecystectomy age:20-80 years old Exclusion Criteria: nalbuphine allergy chronic pain active liver disease that would affect metabolization of nalbuphine patient who had regular pain medications patient who could not cooperate to the evaluation of the survey dementia or other psychiatric disease