FWIW, I keep my Trimix vial in the freezer. I'll defrost it, fill 10 or so syringes, draw the syringes back so there is air space inside...then freeze it all. Come time to use it, I get a pre-filled syringe out of the freezer and hold it in my hand for a minute or two. Good to go.
For traveling, I have a freezer pack - carry the vial in that along with empty syringes. The 3/10 cc 30 ga syringes are good - easier to get a more precise dose.