Mandevilladamaged stem!!!

I just transplanted a 2 stem mandevilla to a pot with a topiary support. Getting it off the original trellis and onto the new one I twisted one of the stems near the base. It isn't completely broken but I am afraid it might die.
Is there anything I can do?
Sandy R

If you didn't sever the artery, you can 'splint' it with some tape and a tooth pick or match stick or twig, and it will be ok for this season. Cut it off this fall when you bring it in, and it will generate more leaves where you cut it off, just under a set of leaf nodes.

Thanks Kay!
I was hoping a little first aid would work--will try it.
Actually I had never thought about bringing it indoors this fall--good idea.
SandyR