Sentence Correction

I have doubt lurking in my mind since I saw a question in Gprep which has subjunctive in past form.The present tense of the sentence is just like this:

The federal rules are established to ensure that patients be warned before check up and that independent doctor evaluate the case.

Can anybody please tell me what would be the past form of this sentence ?
I would really appreciate that. Thanks !!

we are learning gmat rules, not general grammar of English. Although gmat rules are based on general grammar, some rules are different.

so. study specific questions from a good sourse or waste your time and energy. that is my idea