The poem
This living hand, now warm and capable Of earnest grasping, would, if it were cold And in the icy silence of the tomb, So haunt thy days and chill thy dreaming nights That thou wouldst wish thine own heart dry of blood So in my veins red life might stream again, And thou be conscience-calmed - see here it is - I hold it towards you.

Is this poem talking about bringing someone back from the dead? Is is a ghost?
The picture I am getting is that the speaker is dead, his hand is warmed by the hand of a loved one he has left behind, who wishes her own death because of her loss. He would become alive again if she joined him in death.
Keats seems so upset, to the point where he wants to just reach out and kill someone with his own hand. He realizes as he is seeing blood coming out of his body that any minute he will die and wishes that [whoever this is address to] dies instead of him, that he doesn't deserve to die, that this person whomever this is addressed to deserves to die. He wants this person to feel guilty of his death to gain conscience that they are the ones who should have died instead. He wants this person to feel his suffering.
Keats is writing this to his lover. He fears that he is about to die. He recognizes that when he dies his lover will be distraught. She will wish herself dead that he might live again. He writes this poem to comfort her. He is holding out this poem writing with his living hand as a hand from the grave. She can read it when he is dead and know that when alive his hand then alive and warm wrote that to her and he loved her and wished her comfort.
Quite ghoulish isn't it. I feel it highlights a different age, where belief in the afterlife was much stronger and perhaps the imagination was more prone to attacks of the vapours like this. I like this poem, however, I can't visualise it without hearing the voice of Vincent Price!!! I don't think this poem is intended for a loved one, except maybe in the sense of Keats feeling rejected by a former love.
I feel this poem is an act of revenge, an attempt to make someone feel guilty for some perceived slight on Keats' part. Very gothic, very powerful and evokative of dark nights, candlelight and ghost stories
I think that what John Keats meant to said was that his hands will be a reminder that even though he is not there with her, he will always be with her, because now his hands are warm like his love for her, and that when he dies, she will just have to remember his warm hand and just because of the memory he will come back to life in her dreams and nights.
This is the poem which ends a recent biography of Jim Morrison (of the 60's group, The Doors). It is incredibly apt - how at the last moment 'this living hand' reaches right off the page towards the reader!
i read this inj oxford, and my analysis was that he is holding a hand out for a girl to hold, and is telling her that if she doesn't take this opportunity to hold it now, she will feel guilty when he's dead. the professor seemed to like that at least. it comes across to me as rather bitter and darkly funny, in the way he describes the horror she will feel in the future in such detail and then simply states that he's holding his hand out to her now.
Actually, if it's any help, John Keats had been diagnosed with tuberculosis at the time of writing and had just witnessed his brother die from tuberculosis.
poetry
the poem is all about the dead whose hand is hold by his lover