IRCT20190409043219N1 IRCT 2019-05-25 Tehran University of Medical Sciences effect of ketamine on postoperative shivering Comparison between ketamine 0.25 mg/kg and ketamine 0.5 mg/kg for relieving postoperative shivering after elective abdominal hysterectomy 2019-05-22 anticipated 96 Complete https://irct.ir/trial/38943 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Used, Assignment: Parallel, Purpose: Prevention, Randomization description: Patients were randomly allocated to 1 of 3 treatment groups using balanced block randomization, Blinding description: The study medications are prepared by an anesthesiologist who does not otherwise participated in the study and then are enveloped and sealed and patient′s code are recorded on it. The envelopes will open in operation room 20 min before the end of surgery by an anesthesiologist who is blinded to patient′s study group and type of solution. All of the nurses and patients are blinded to the type of solution and to the patient′s study group allocation.also the nurse who fill the questionnaire. 3 post operative shivering. Intervention 1: Intervention group: :injection of 0/25 mg/kg ketamin intravenously with 2 cc volume, 20 minutes before the end of surgery. Intervention 2: Intervention group: injection of 0/5 mg/kg ketamin intravenously with 2 cc volume, 20 minutes before the end of surgery. Intervention 3: Control group: 2cc normal saline intravenously , 20 minutes before the end of surgery. No - There is not a plan to make this available Justification or reason for not sharing IPD is no more information