How can someone's blood literally boil when they go into a plane at too high an altitude?

Question

How can someone's blood literally boil when they go into a plane at too high an altitude? 
They said it was called the bends on tv. I've heard of the bends but only when people go diving and then they have to go into this chamber. The bends in water is caused by the divers surfacing too quick but the mechanisms that causes this is not fully understood by me. I suspect that it has to do with the pressure down in the ocean right? Is the bends caused by going to a high altitude also the same as the bends caused by surfacing too quick after diving?

Thanks=)

I found conflicting stories on the web so I haven't hot linked you to any of them. Many appear to be blogs so there is no scientific data to back up their thoughts. One medical journal talked about loss of oxygen but they gave only a summary and it takes a subscription to read the entire article. That article reportedly talks about your question. I suggest you go to www.google.com and type in "blood boil high altitute" (without the quotation marks) and select what you want to read.

Okay Thanks Dr.Bob =)