Release without ejaculation.

Patient: I am a gay man and have a partner, I have HIV and he does not. We always use protection, however I know condoms can break. I read wikipedia and heard that it is possible to release the contents that would normally release during an orgasm before you actually achieve an orgasm. Is this true? The reason I ask is I would like to be able to do so as an extra (note I said extra not singular) precaution? I think having most of it gone, PLUS the condom would be a great help as a backup. I can’t figure out if this is true, or even how to do such a thing. Some would poo poo this question but it’s very important to me.