The aim of this work is to compare the hemodynamic and analgesic properties of Dexmedetomidine and Magnesium sulphate infusion in lower abdominal surgery.

Dexmedetomidine is a relatively new alpha 2 adrenergic receptor agonist with a higher α2/α1 selectivity ratio of 1620:1 that provides analgesic and anesthetic effects . Dexmedetomidine has various clinical uses in anesthesia such as sedation, and prolongation of the duration of postoperative analgesia when used as an adjuvant through intrathecal, epidural, or intravenous routes.

Magnesium sulphate is another commonly used drug in anesthesia. Magnesium sulphate suppresses nociceptive impulses through inhibition of voltage-gated calcium channels and through antagonism of the N-methyl D-aspartate (NMDA) receptors.

Although both drugs were reported to prolong the duration of spinal anesthesia, no studies to the best of our knowledge had compared the analgesic and hemodynamic profile of both drugs when used as intravenously during spinal anesthesia.

Inclusion Criteria:

• Adult patients aged between 18 and 65 years.
• Scheduled for lower abdominal surgery.

Exclusion Criteria:

• Systolic blood pressure less than 100 mmHg
• Coagulation disorders
• History of heart failure
• Mitral or Aortic stenosis