You're definitely not the only only one, Tkdgurl. Quite a few of my friends here have told me about men messaging them and wanting to meet right away with little or no conversation ahead of time. It can go the other way, too. I've had people e-mail me wanting an exam but not really interested in getting to know me first. Either way, it's just not a good idea.
While I do not know of a magic formula for assuring both safety and discretion in real-time meetups, you definitely need to talk a good amount beforehand. Here are some things to think about:
1) Do you get the feeling that this person is honest and genuine? That doesn't necessarily mean revealing everything about oneself (especially in this type of forum), but if you sense deception, inconsistencies, and/or things that just don't add up, that should serve as a warning.
2) Do you agree on what you want to happen in a play experience? It's important to talk through the specifics at least once, preferably more. Just because someone says they are also into med-fet does not mean you're on the same page. What procedures does the playdoc want to do? Are those okay with the patient, or are some off limits? What will be the general tone of the exam? Are you keeping it very professional and clinical, or will it be eroticized/sexual? (And be clear on exactly what that means.) If the other person repeatedly tries to pressure you into something you don't want to do, that's a red flag.
3) Do you basically get along well? Can you talk about things that aren't fetish-related? Does he/she seem to be a nice person overall?
4) This isn't always possible, but if the playdoc has experience, can you speak with some of his/her previous patients?
5) This isn't an ironclad requirement, but it's a good idea to voice chat (e.g. via YIM, Skype, or phone) before you actually meet. There are things you can pick up about someone's overall demeanor and and personality when you actually talk that you just can't get over e-mail or IM. (I've had at least one case where despite many hours of IM chat, a prospective patient always found excuses not to voice chat; in the end I discovered she had been lying about many things and was not at all who she portrayed herself to be.)
6) Finally, when you actually do meet in person, spend some time together in a public place, outside the "exam room", just talking about normal stuff (although you can certainly discuss some fetish/exam stuff too). It doesn't necessarily have to be for all that long (for most of my initial meetings it was maybe an hour), but this in-person interaction is very important in giving you a better feel for who this person is and whether you're comfortable proceeding.
So far I have met three patients in person and have not had a problem. In each case, we had chatted for a while and discussed the details well in advance. When we actually met, I felt very comfortable with each of them, and I believe they felt the same way. As expected, things went very well. Now I have heard of some less ideal experiences people have had when something seemed amiss and they did not trust their gut, but so far I've thankfully managed to avoid those!