Bicarb is the big one that sticks out in my head. That is the only one I routinely mention when I teach anyway...
Mag can be used for VF or VT, but it seems like the only condition where the evidence indicates it is truly superior to any other drug is in polymorphic VT (TDP). As far as having to call for orders to give it for VF but not for TDP, in the heat of battle, those squiggly lines can get awfully difficult to interpret sometimes...
The thing that I don't like about mag is that most people tend to push it too fast. It is supposed to be given over 3-5 minutes during arrest. How often do you think that actually happens, especially in the field? My reasoning on this is that we should push slowly until conversion, then stop and hang a drip. The lower the amount necessary for conversion the better.
Pushing too fast leads to the risk of conversion with dramatic bottoming out of blood pressure, meaning they will effectively be in PEA until you either start pressors/inotropes or the mag wears off to the point that there SVR increases enough to begin producing a pulse again.
This is my thoughts on the matter anyway. To be honest I really rank lido and amio about the same on effectiveness scales, although I use amio nearly 100% of the time, because it is what we have, and it seems to work well enough...nothing better or worse available.
I think there is a lot to be studied regarding the effectiveness of epi as a vasopressor as pH decreases in the patient who is in arrest. In fact, some studies have shown that the effects of vasopressin appear to be unaltered in the acidic patient, where the effects of epi tend to decrease dramatically. This could lead one to think that instead of considering vasopressin early in the code, perhaps we should be considering it later?