IRCT20180921041078N1 IRCT 2020-12-26 Esfahan University of Medical Sciences effectiveness between lidocain and meperidin in anal fissure Comparison of the success rate of spinal anesthesia with lidocaine and spinal anesthesia with meperidine in anal fissure surgery. 2018-08-24 anticipated 120 Complete https://irct.ir/trial/34361 interventional Randomization: Randomized, Blinding: Double blinded, Placebo: Not used, Assignment: Parallel, Purpose: Treatment, Randomization description: The anesthesiologist performs spinal anesthesia with lidocaine and pethidine as one of the patients, and the surgeon does not know how the drug is used in spinal anesthesia. Also a surgical nurse who does not know how to operate (blind sampling), Blinding description: lack of patients awareness lack of surgeon awareness to plan of spinal anesthesia. 3 chronic anal fissure. Intervention 1: Intervention group: The patient is placed in a sitting position after rinsing the back with betadine solution of 24-gauge Quinke spinal needle No. 24 (24-gauge Quinke spinal needle) enters the intrathecal space between the fourth and fifth lumbar vertebrae and after confirming the intrathecal space with fluid out The spinal cord is used from the end of a 25 mg pethidine needle. The patient remains seated for 5 minutes and then the patient is placed in a suitable position (lithotomy) to perform the relevant operation. Intervention 2: Control group: The patient is placed in a sitting position after washing the back with betadine solution of 24-gauge Quinke spinal needle No. 24 (24-gauge Quinke spinal needle) enters the intrathecal space between the fourth and fifth lumbar vertebrae and after confirming the intrathecal space with fluid exit Spinal cord From the end of the needle of lidocaine drug 0.5 ml of 5% lidocaine is used. The patient remains seated for 5 minutes and then the patient is placed in a suitable position (lithotomy) to perform the relevant operation. No - There is not a plan to make this available Justification or reason for not sharing IPD is Final incompletness