Ethical implications : pain, coma and related disorders

Pain is a subjective first-person experience. Severely brain-injured patients with an altered state of consciousness cannot communicate their feelings and possible pain perception. Nevertheless, existing scales do not specifically assess pain perception in noncommunicative patients recovering from coma. Previous studies have shown that brain processing linked to pain in vegetative patients is different from what is observed in healthy volunteers. On the contrary, minimally conscious patients have been shown to have a brain activity similar to healthy volunteers in response to painful stimulation. This article examines the current knowledge base for guiding decisions regarding assessment and management of pain in patients recovering from coma.