The poem plays on one small trick: the title "Off ice" is just "office" split in two. Once you notice that, the whole thing reads like a pun with a chill in it. The office becomes a frozen place, and the speaker wants out of it.
The speaker describes handing out "answers to a bore," which suggests dull, repetitive work for someone or something that hardly deserves the effort. Then comes a stranger line: being "glad of being bled." It's an odd kind of gratitude. Judging by the imagery, the job drains the speaker, yet there is some relief or even pride in being used up, as if being emptied at least means being needed.
The last lines are a quiet wish: "I hope to get off its ice." The mood is dry, wry and a little numb. The humor is light, but underneath it is a tired longing to thaw out and leave.