Fifty children undergoing heart catheterization without local anesthesia in the skin will be randomly divided into two groups.

Group DM (Dexmedetomidine + Midazolam) and Group KM (Ketamine + Midazolam)

Fifty children undergoing heart catheterization without local anesthesia in the skin will be randomly divided into two groups.

Group DM (Dexmedetomidine + Midazolam) will receive dexmedetomidine 1 µg/kg IV over 10 minutes and midazolam 0.1 mg/kg IV as a bolus concomitant with induction, followed by a continuous infusion of dexmedetomidine at 0.5 µg/kg/h and midazolam at 0.1 mg/kg/h for maintenance.

Group KM (Ketamine + Midazolam) will receive ketamine 1 mg/kg IV and midazolam 0.1 mg/kg IV as a bolus for induction, followed by a continuous infusion of ketamine at 1 mg/kg/h and midazolam at 0.1 mg/kg/h.

Inclusion Criteria:

• Scheduled for elective cardiac catheterization under general anesthesia.

Exclusion Criteria:

• neurological disorder, psychiatric disease, or current psychoactive medication.
• allergy.
• significant systemic comorbidities.