Re the first aid thing:
I have all cast and crew submit a CONFIDENTIAL Emergency Medical form which is destroyed on closing night (I have my first aid cert.) with a section "Course of action during such event" section. Then if I have people in the cast with such things as eppilepsy, diabetes etc, I talk to them individually and say something like "During the second rehearsal, I am going to do a basic 10 minute crash course on things that could go wrong medically and how the first on the scene should deal with it. You mentioned you had xxx, and I felt that it may be suitable to bring up what to do in case something does happen. I will not mention you by name, there are others who also suffer from it, is that okay with you?"
Upon getting the Okay from them, I then inform my cast of what to do in an emergancy - ie not to stuff something down their throat if they are fitting so that they don't swallow their tongue - how many times must people be told that they are more likely to choke on the rag or whatever, than to choke on their tongue!
I also tell them where a quick sugar source can be found - this I find is essential even if there are no diabetics, where water is, where ice packs are, bandaids etc. then I tell them "If there is something whichyou cannot deal with, notify me imediatly, either over cans, or come to the booth. Do not call an ambulance"
The reason I do this is many places, ie where I am, have special access requirements - ie to get an ambulance right up to the door, security is rung using 333 on an internal phone instead of 000 (the national emergancy number) and they call the ambulance, remove the pylons blocking access and wave the ambulance through to the right place. I may also be able to page a doctor (as we ask anyone who may be needed to be contacted in emergancy get their staff to ring me in the bio box instead of having their mobiles on, and we can get them by paging them, or via the FOH staff)
I don't leave the booth in these cases - the only phone that will reach security is in the booth. The only number I can be contacted on is in the booth. In cases where I may be needed to assist with stabalising, I will get my LX, Sound Op or other person in the booth to 'take the wheel' whilst I run back stage. Currently if I have to do that, it takes me 2 minutes without interupting the audience (leave through the external door of the bio box, run down a flight of stairs, run arround the theatre, and into the back stage workshop) , or 20 seconds if I do - down a spiral staircase, across the stage.
Developing an emergancy plan is essential. Usually if there is a dimmer fire or something like that the LX op can run and do that, and I can press the go button. If someone leaves something back stage and it is needed, I have full confidence in my ASM who is back there.