Aim: This work aims to compare the postoperative analgesic effects and side effects of Dexamethasone orMagnesium sulfate (Mg) that added to bupivacaine.
Patient and Methods: Eighty patients aged between 16–70 years with ASA I– II who were scheduled for infra-umbilical surgeries under spinal anesthesia were enrolled in our study after written informed consent and approval of ethical committee; This Study was conducted in Sohag University Hospitals from August 2016 to March 2017. Patients Were divided into 2 equal groups:- (Group A) 40 patients received 50mg magnesium sulphate added to2.5ml volume of 0.5% hyperbaric bupivacaine plus 0.5 ml Normal saline.- (Group B) 40 patients received 4mg dexamethasone added to 2.5ml volume of 0.5% hyperbaric bupivacaine. Under complete aseptic conditions, spinal anesthesia was carried out in the sitting position, at level (L2-3 or L3-4). After a free flow of cerebrospinal fluid was confirmed, each patient received one of the coded spinal solutions (GA or GB).Immediately after administration; the patients were turned into the supine position. Patients were monitored for: Heart rate; NIBP and Oxygen Saturation. Patients were observed for onset, duration of sensory block and motor block; In the post-anesthesia care unit (PACU), the patients were asked to assess their level of pain based on a visual analog scale (VAS). Complications also were observed .

Results: Dexamethasone had a faster Onset of sensory block onset than Magnesium Sulphate; Dexamethasone had a longer duration of regard Duration of motor block than Magnesium Sulphate; Magnesium Sulphate group had a longer analgesic effect stayed longer than Dexamethasone group .No Significant difference Between Two groups in rate of Complications ; Hypotension and Bradycardia were the most frequent complications in the two groups .Conclusion: the addition of Dexamethasone 4mg or Magnesium Sulphate 50mg to intrathecally injected Bupivacaine improved the effect of