Except that, in the UK at least, no central register of Deeds Poll is kept?
Unless they are "enrolled" i.e. lodged for safe keeping, in the Close Rolls of the Chancery (from 1851 to 1902) and from 1903, in the Enrolment Books of the Supreme Court of Judicature, which is located within the Royal Courts of Justice in the Strand, London.
Since 1914, for "enrolled" changes, the details of the name change are published in either the London Gazette or Belfast Gazette.