I'm not an anxious person per se, and I've never had an anxiety attack, but I know what it feels like to not be able to breathe. Coming out of anesthesia one time I felt like I couldn't breathe and when I tried to say, "Help", I felt like I couldn't say it. Luckily my Dr. came into the recovery room, spoke in a calm & soothing voice, told the nurse to give me a shot of Demerol (I think). Then I could breathe.
Feeling like you can't breathe feeds back into the anxiety and increases it.
Perhaps recognizing when you are in the early portion of a full fledged panic attack could help you, as in, when you start to have one, tell yourself it will pass just like it has passed before.
Also, I think it helps to have a calm soothing person tell you "It's okay...you'll be alright."
Being in a dangerous profession is hard. So, hang in there.