Who would feel pain if there is no more identification with it? Have you ever seen somebody bleeding and the thought, "Ohh, he must suffer", but as soon as you asked him, he even did not know that he bleeds. That is in case of uncounciousness out of ignorance. There is also the case of no surface (uncounciousness) out of understanding.
If you search for a sample for it, this might be useful even it is not rally correct compareable.
Or you might know shock situations, where the mind is so aware, that there is no real sensation even there are heavy wounds.
Just that! *smile*
BUT! it is important to become a real Buddhist first. Like Punna did: Nate sante baram sokham _()_