This article presents the ethical situation that evolves the discussion of limitation of treatment offered to patients in a persistent vegetative state. Health professionals find themselves in difficult situations when dealing with these recurrent problems in their daily professional activities. This is presented, then, as an ethical issue of difficult solution, the decision of suspension of life support tasks. The debate is sustained, however, on how to distinguish the concepts of terminality of life, orthothanasia, euthanasia, dysthanasia, palliative care and, in (...) an specific case, a persistent neurovegetative state, with its implications in the use of disproportional treatment that prolongs life, in a painful and a futile way, of the process of agony to the death. There are questions or dilemmas involved in this debate, such as in which moment the suspension of treatment can be considered adequate or the use of all possible measures to maintain life, even in advanced, irreversible and terminal illness are ethically acceptable. And finally, who is responsible for the suspension of therapeutic procedures in the irreversible and terminal clinical situations. (shrink)