As far as I understand: a regular bubble of air, while undesirable, won't kill you. That's part of what the lungs are for, and in fact it happens in hospitals all the time.

A very large bubble can kill you, but you need to put some serious effort [1].

[1] http://www.straightdope.com/columns/read/2866/can-air-inject...

sure, but concerns like that are why the epipen`cil came to be

in emergencies you are stressed and on a time constraint

if one takes the time to prepare for such an emergency by constructing the epipencil i would hope thae would follow the instructions given carefully, which notes:

7) Inspect carefully to make sure there are no air bubbles, and remove them if present.

i sent them an email requesting that they explicitly describe in the instructions and verbally describe in the video how to ensure the syringe is bubble free