Advance directives, best interests and clinical judgement: shifting sands at the end of life.

End-of-life issues for clinical practice present complex ethical, moral and legal dilemmas that have been heightened by advances in medical technology enabling a dying patient to be kept alive for longer than ever before. Respect for patient autonomy and dignity are fundamental ethical components that engage in end-of-life decision-making. A mentally competent individual has the absolute right to refuse medical treatment for any reason and a valid advance directive for the refusal of treatment is binding in the event that the person loses capacity. In the incompetent patient, the withdrawal of life-sustaining treatment is based on the 'best interests' test, developed on a model that takes into account the welfare considerations of the person concerned. It is questioned whether the test should be more subjectively based, and accord greater weight to the wishes that might have been in the mind of the incompetent person approaching the end of life. The Mental Capacity Act 2005 (expected to come into force in 2007) provides a statutory framework for the law relating to advance directives, capacity and best interests. This paper examines contemporary issues surrounding end-of-life decision-making against the backdrop of the existing and proposed legal framework.