dilaudid

Have a pt with neck ca with mets to brain. Major pain issues that I think we are under medicating. Since he is NPO all meds are IV push, transdermal, GTube or SL. Right now he is somewhat confined to the nursing home because of the need for frequent IV push prns.
We've been upping his Diluadid and he is now at 10mg every hr and prob takes it at least 16 times a day, MS IR 80 mg at least 10 times a day and of course the 400 of Fentanly. I think we can be managing his pain with a pca or drip better. Do any of these meds reach a max where they are no longer effective? Trying to get a pain referal or at least an onocologist who might have a better treatment plan.

Any input?