IRCT2012101711147N1 IRCT 2013-11-11 Birjand University of Medical Sciences, Vice Chancellery for Research and Information Technology Effects of two spinal anesthesia approaches in the incidence of headache, backache, and regression of sensory level after operation Comparison of median and paramedian approaches to spinal anesthesia in terms of the incidence of headache and backache, and the regression of spinal sensory level in patients undergoing elective cesarean section 2012-09-05 anticipated 138 Complete https://irct.ir/trial/11480 interventional Randomization: N/A, Blinding: Single blinded, Placebo: Not used, Assignment: Parallel, Purpose: Prevention. 3 elective caesarean section. Intervention 1: In the first group, a 23- gauge blue needle is inserted at the L4-L5 vertebral level, and lidocaine 5% in a dose of 0.7-1 mg /Kg is injected into the subarachnoid space for spinal anesthesia with median approach (Lidocaine: trade name: Xylocaine, chemical composition: 2-6 dimethyl phenyl, manufactured by Iranian Medicinal Company of Daroo Pakhsh). (In this approach, the spinal needle is inserted from superior boarder of spinous process of inferior vertebra in the midline of the selected space). Intervention 2: In the second group, a 23-gauge blue needle is inserted at the L4-L5 vertebral level, and lidocaine 5% in a dose of 0.7-1 mg/Kg is injected into the subarachnoid space (Lidocaine: trade name: Xylocaine, chemical composition: 2-6 dimethyl phenyl, manufactured by Iranian Medicinal Company of Daroo Pakhsh). (In this approach, the spinal needle is inserted 1 cm external and 0.5 cm inferior into the selected space with 20 degrees toward the L4-L5 vertebra).