IRCT20151012024493N3 IRCT 2019-03-10 Shahid Beheshti University of Medical Sciences Comparison of the role of intrapleural pethidine injection with intravenous morphine in the management of post-operative pain after open cholesystectomy Comparison of the role of intrapleural pethidine injection with intravenous morphine in the management of post-operative pain after open cholesystectomy 2018-03-21 anticipated 80 Complete https://irct.ir/trial/36072 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Used, Assignment: Parallel, Purpose: Treatment, Randomization description: Sealed envelope method: The assigned group is written on a paper within sequentially numbered, opaque, sealed envelopes. Investigators should only open the envelopes sequentially, right before the beginning of anesthesia for each patient, Blinding description: The patients are not aware of the type of the applied technique. The chief researcher who is responsible for patient's safety and preparing the drugs, is aware of the techniques administered. But the resident and the nurse in the recovery ward do not know which technique has been used. The coding of the groups are numerical and the statistical analyst and the laboratory personnel are not aware of the coding type. 3 Open cholecystectomy. Intervention 1: Control group: At the end of the surgery,the patient receives the neuromuscular reversal agents and the infusion of propofol and remifental continues.A metallic epidural needle is inserted in the right fifth intercostal space at the midaxillary line.The correct placement of the needle within the intrapleural space is checked confirmed by the suction of water drop into the space( hanging-drop technique).The total volume of 20 milliliter of the drug is injected, which is normal saline in the control group.In this group 0.1 milligram per kilogram of body weight of morphine sulfate is injected intravenously. Intervention 2: Intervention group: At the end of the surgery,the patient receives the neuromuscular reversal agents and the infusion of propofol and remifental continues.A metallic epidural needle is inserted in the right fifth intercostal space at the midaxillary line.The correct placement of the needle within the intrapleural space is checked confirmed by the suction of water drop into the space( hanging-drop technique).The total volume of 20 milliliter of the drug is injected, which in the intervention group is 50 milligram of Pethidine diluted in saline. Undecided - It is not yet known if there will be a plan to make this available Justification or reason for indecision in sharing IPD is The group has not reached a consensus yet.