Is it possible to translate the name of a field in the CP?
Static text on the front-end and Craft CP translations are handled through your translation files.

All you need to do is name your fields without the translate filter and make sure they have suitable translation arrays in your translation files.

It's also worth mentioning you will need Craft Pro to take advantage of localisation and translation features.

Here is an example to get you started, this will be added to the translation file for your German locale:

&lt;?php

return array(
    'Surname' =&gt; 'Nachname',
);