In other news, Darwin called it! The adrenaline rush=mega puke for the uninitiated. Adrenaline results in the movement of the blood from your gut to your limbs for that flight or fight response. However, taking the blood out of the digestive tract leads to the unfortunate side effect of teh blaaarrrggs. This is why some people may blow chunks after a car crash, near death experience, period of intense stress, etc.
Heh. That could have sounded much more scientific if I wanted it. The action is over for now, and the next bit is all story. More deaths in Arc 4: The Yeti, all you redshirts looking forward to it.