My buddy was shooting, and went to register but wasn't in. pushed a lil deeper and registered. but with the failed register, an air bubble with the volume of a mL or two was in the barrel. Thought nothing of it, and slammed home. within seconds, the air bubbles were felt and heard in my shoulder. like my boy could FEEL the bubbles going up my arm. was scared shitless! now every time IV is used, a lil air always ends up in the vein. I leave a really small air pocket so that blood can rush in and take that place, and it never seemed to have any adverse reactions.

so is this something of serious concern?
I searched, but the results were completely irrelevant.