Being by Kevin Brooks

Taking place in Essex London, Robert Smith always thought he was a normal boy. Sure he lived in foster home after foster home, but that was normal for him. As he's getting an endoscopy to check for stomach ulcers, everything goes completely wrong. Conscious but still anaesthetized he starts hearing all the commotion from the doctors. Instead of normal organs they find highly advanced technological implants. Scared, the doctors call in a shady government official to check it out, from there the adventure starts. Robert is on the run and with the help of girl named Eddi Ray he hopes to get away from the government officials that are after him.