A man who had just undergone a very complicated operation kept complaining about a bump on his head and a terrible headache. Since his operation had been an intestinal one, there was no earthly reason why he should be complaining of a headache.
Finally his nurse, fearing that the man might be suffering from some post-operative shock, spoke to the doctor about it.
The doctor assured the nurse, “Don’t worry about a thing. He really does have a bump on his head. About halfway through the operation we ran out of anesthetic.”