I agree that they can be triggered by the being in the same situation, even when you are not in the same 'frame of mind' as when the first one happened. During a real stressful period of my life a few years back, mainly due to coping with the death of a parent after a long and distressing illness, I had my first panic attack.

I just happened to be in a smallish room at a friend's workplace with venetian blinds on the window. I remember it was sunny and the slatted glare coming through the blinds began to 'flash', thereon followed a full blown panic attack. I had never had one before and thought I was dying, and am not prone to melodrama usually. Getting out into the fresh air and deep breathing and water controlled it, but it was damn scarey. Over the next twelve months I had to revisit that same room approx monthly, and everytime I sat opposite the venetian blinds it started again. I couldn't get my breath and my heart raced.

Eventually like Jeri I decided to try and be 'bigger' than the panic attack and forced myself to ride it out, all the time telling myself I could do it. It sounded so crazy I hadn't told anyone except the friend who worked there and had seen and helped me previously. It took a few shaky attempts until I could walk into that room and know I would be ok. Never had one since, but could spot the warning signs now, and would probably head out into the fresh air immediately if I felt one coming on.

But having said that, it only worked for me because it was a panic attack with no medical cause as such, well apart from stress. As others have said it may be worthwhile trying to determine if there is an underlying medical condition causing them. Good luck.