Может
select col.name as [Col], o.name as [Table]
from syscolumns col inner join sysobjects o on col.id=o.id
where o.xtype='U'
and
not exists
(select 1 from syscomments sc inner join sysobjects so on sc.id=so.id
where upper([text]) like '%'+upper(col.name)+'%'
and so.xtype in('V','TR','P'))