her like that, i just thought, i got to get her free. >> bystanders watch the bear squeeze his enormous head through the bars. they're confused and horrified. binky plunges his four-inch long i canines firmly into katherine's left thigh. his teeth are dangerously close to the main femoral artery in katherine's leg. dr. rayford knows there's not much time left. >> in all my experiences as a physician i'd never, ever seen anything as frightening as what i saw that day. had the polar bar severed her femoral artery, she would have bled to death in a matter of seconds. can somebody call someone? >> someone is coming. >> kevin springs into action, trying everything he can to free the flailing woman. >> i jumped over the first fence and threw my radio at him. just bounced off his head. then i grab aid hold of katherine, and it was just like playing tug-of-war. >> get a gun!