METHODS	The children were assigned randomly to four groups : ( I ) clonidine 1 microgram kg-1 added to caudal bupivacaine ; ( II ) clonidine 3 micrograms kg-1 added to caudal bupivacaine ; ( III ) clonidine 3 micrograms kg-1 i.v. and caudal bupivacaine ; and ( IV ) caudal block with bupivacaine , no clonidine ( control ) .\