Star Surgeon

Here are all the strange and not so strange creatures who inhabit James White's hospital in space as both doctors and patients: the human doctor Conway plus two-ton doctors with four-ton patients, creatures which are multi-legged and telepathic, gas breathers, underwater behemoths - a wild and wooly assortment of denizens from all parts of the galaxy.
"Sector General" is a mercy station - a place where all kinds from all worlds are welcome. But for the first time, the hospital itself is threatened by creatures too different to understand its purpose and so powerful that they can cause utter havoc!