Don't keep your IV bags in the refrigerator. There's no point in doing so. Dex, baytril, and a lot of other medications can be kept at room temperature.

Some meds lose their effectiveness, some retain the same strength, while some increase in strength. Expiration dates generally don't mean a whole lot in regards to medications. Most medications are still at effective strengths years after their supposed "expiration" date. If your medication is supposed to be refrigerated, then keep it that way. Follow the instructions on the medications you have, and you'll be ok.