Many if not most theists are under the impression that in a life-threatening crisis, atheists will see the "error of their ways" and turn to God for help. However, that is an erroneous assumption. Like many other non-believers, I know this from personal experience. I recently came through a personal (health) crisis involving what appeared to be a possibly life threatening medical condition. But fortunately, the test came back negative.
During this time not once did I waiver in my position that there is no evidence for the existence of a supreme being to save me, especially one who requires prayer (groveling) to consider intervention and who then may or may not intercede depending on what kind of a mood he's in and on whether or not I've said the magic words and in the right way.
Of course, while waiting for the examination and then its outcome I was very distressed as I don't handle uncertainty very well. But my biggest concern is how would I tell my wife if the results turned out positive. In short a sky daddy was hardly on my radar during this period. In 2002 I wasn't so lucky and was in fact diagnosed with a severe illness but made a full recovery. At that time I likewise "kept the non-faith".
Yet what I've experienced is nothing compared to that of noted author Christopher Hitchens who is is suffering from esophageal cancer. Hitchens is a prominent atheist and has remained steadfast in his non-belief. In spite of his ill health, he participated in a debate with Tony Blair in November about whether or not religion is a force for good in the world and proceeded to clean Blair's clock.
Regarding his illness, Hitchens has said that if his condition deteriorates and as a result, he become a theist, let it be known now that he would not be in his right mind for doing so.
In the final analysis people like Hitchens are not only an inspiration in a society that for the most part is guided by irrationality regarding religion. He is a reminder to believers that there certainly are atheists in the proverbial fox holes after all and when the going gets tough, the tough use reason.