evaluate the synergistic efficacy of propofol and caudal dexmedetomidine for postoperative EA in pediatrics aged from to 2 to 5 years maintained on sevoflurane inhalational anesthesia and scheduled for conginital inguinal hernia repair surgeries

Eligibility and type of the study: This prospective randomized placebo-controlled double-blind study will be conducted after approval from the Institutional Ethics Committee and obtaining written informed consent from parents of children scheduled for conginital inguinal hernia repair procedures under general anesthesia. This study will be conducted at pediatric surgery operating theatre, Assiut University Hospitals.

Sample size:

Drugs coding and Randomization: Patients will be randomly allocated into three equal groups with the help of a computer-generated table of random numbers to receive the study drugs. One anesthesiologist, not involved in the study procedure or data collection, will prepare the study drugs in identical coded syringes. Access to these codes will be only available to one anesthesiologist who will prepare the syringes according to the study drugs used. To ensure double-blinding, the anesthetic technique and outcome data will be collected by an anesthesiologist not included in preparing study drugs or envelops coding. Also the parents will be blinded to the drug grouping of their children.

Inclusion Criteria:

• Age 2-7 years
• Both genders
• American society of anesthesiologists (ASA) physical state I-II
• Children undergoing sub-umbilical abdominal surgeries

Exclusion Criteria:

• Guardians refusal
• Congenital anomalies at the lower spine or meninges
• Increased intracranial pressure
• Skin infection at the site of injection
• Bleeding diathesis
• Known allergy to any drugs used in this study
• Children with behavioral changes; physical or developmental delay; neurological disorder or psychological disorder.
• Children on sedative or anticonvulsant medication.