Pediatric Caudal Dexmedetomidine Enhances Postoperative Analgesia of Magnesium Sulphate in Lower Abdominal Surgeries

Inclusion Criteria: * Healthy male and female children, ASA I and II,Aged 6 months to 6 years, , undergoing elective surgical procedures expected to last more than 90 min, and scheduled to receive general anesthesia combined with caudal extradural block Exclusion Criteria: * Allergy to local anesthetics,coagulation disorders, infection at site of injection, anatomic abnormalities and congenital anomalies like spina bifid, ASA III or higher, Parental refusal and the current use of Calcium Channel Blockers or Medication that may affect the neurologic system