In response to the OP, there's three ways I've found to deal with potentially panic inducing situations. The first is accepting that there will be problems. The biggest situational stressor's I've experienced are a "now what do I do?" when things did not go according to plan. Things WILL go wrong. That's what adaptability and contingency plans are for.

The second comes from (I think) shooting disciplines: "Slow is smooth and smooth is fast". Taking a couple of seconds to compose yourself before making a decision (STOP, THINK, OBSERVE, PLAN), slow down when taking action.

Lastly, make practice runs. I know this is going to sound cliché, but the more you do it, the less stressful it is. My first time up on stage, I was freaking out. The last time, I just ignored the audience.
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EDIT: I know that the panic attack offshoot is being shut down, but I had to add my $.02.
Been there, done that. You're shaking, sweating, gasping for breath, and feel like there's no room in your chest for your lungs to expand. You just have to wait it out. Find a relatively low stimulation location and just concentrate on breathing. It takes about 1/2 hour to completely ride it out. Qi Gong breathing helps.