Dexmedetomidine ( 0.5 g/kg , 1 mL ) and normal saline ( NS , 1 mL ) were given by intranasal route 40 minutes before induction , and then NS ( 20 mL ) and dexmedetomidine ( 0.5 g/kg , 20 mL ) were given intravenously 10 minutes before induction , respectively , in groups D1 and D2 .