This happened back in 1973, and from what I remember, the only thing that saved him is that they held the pole in place which kept the blood loss to a minimum. Even with that, Clint was still pronounced dead at one point. But as they say, that pronouncement was greatly exaggerated and he's still with us to-day at age 79. If you're a Cheyenne fan or a Dirty Dozen fan you can click on the link and get yourself and autographed photo, direct from The Big Guy himself.
I thought about this due to the Steve Irwin stingray-barb-through-the-heart story. I've remembered this little bit of trivia for 33 years, just so that I could retrieve it now for your education and enlightenment.