Hi, Cally
you are a good sister! Re: the doctor's statement - "(they did tell him that they would take him to the "brink of death" and then bring him back.) - I cannot imagine why they decided to phrase it in exactly that way. Our doctor's phrase - 'the limits of human endurance' was at least not as melodramtic.
As Christine points out, nutrition and hydration make a huge difference - if he is dehydrated it will make everything feel worse. Has he discussed his symptoms with his RO or ENT - or the oncology nurse? If they don't know what is going on, they won't know to help. Perhaps you will be able to advocate for him.
Maria