If your are considering changing you name this can usually be done through a Deed Poll document which shows your change of name.
You can apply for a Deed Poll document online for 29 and this will then enable you to get your records updated into your new name.
As you live in the state of Louisiana, check with the authorities there to confirm they are willing to accept a Deed Poll to show your change of name. If you would like to have your name changed on your passport you should make inquires about how to do so with a local government department, as the law differs greatly from country to country.
Read more: http://www.ukdp.co.uk/name-change-foreig
If they are happy to accept this document (accepted in the UK by all government authorities) the you can apply for a Deed Poll.
There is more information about this process online:
www.ukdp.co.uk
I hope this has been of some help to you.