IRCT20200910048678N2 IRCT 2021-12-18 Zanjan University of Medical Sciences Comparison of the effect of tranexamic acid and dexmedetomidine on the amount of bleeding Comparison of the effect of tranexamic acid and Dexmedetomidine on the amount of bleeding during Spinal posterior fusion surgery 2021-12-22 anticipated 90 Complete https://irct.ir/trial/60567 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Not used, Assignment: Parallel, Purpose: Treatment, Randomization description: At first, the samples enter the study in a convenience method. Then, the samples are assigned to two interventions groups 1 and 2 based on random blocks with a size of 4. Random blocks are created based on the PROC PLAN program and in SAS 9.4 software. In order to be able to match samples in terms of age and gender in each group, after the available samples are identified, samples are divided according to age and gender groups and identified in each group. Random allocation will be based on groups. The groups will be divided into two groups based on the cut-off point of 50 years: over 50 years old and under 50 years old, and in terms of gender, they will be divided into two groups, male and female, Blinding description: Patients know that they are participating in a study that aims to evaluate the effect of tranexamic acid and dexmedetomidine on reducing intraoperative bleeding but are unaware that they are receiving tranexamic acid and dexmedetomidine. The drugs are similar in color and appearance, prepared in syringes, and coded. The anesthesiologist who injects the drug is not aware of the medication that patients receive. 3 Spinal posterior fusion. Intervention 1: Patients in intervention group 2, before surgery and after induction of anesthesia, receive dexmedetomidine (exir pharmacy) with an initial dose of 1µg/kg for 10 minutes and then with a maintenance intravenous infusion at a dose of 0.7 µg/kg/h. Intervention 2: Patients in intervention group 1, before surgery and after induction of anesthesia, receive tranexamic acid (manufactured by Caspian Tamin) with an initial dose of 15 mg/kg for 15 minutes followed by a maintenance intravenous infusion of 1 mg/kg /h. 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 There is no more information.