But
1. It is there.
2. It is functioning
3. It is functional enough to at a minimum
a. sense stimuli to some degree, even if it was minimal
b. elicit a reaction to said stimuli
4. Life is life, pain is just a reaction. The level of reaction does not alter what is inflicting it, and what damage it may cause.
Whether fully awake or fully numbed by anesthesia, an infury is an injury, and enough to kill is enough to kill.