Artificial nutrition and hydration at the end of life: ethics and evidence.

The case of Terri Schiavo resulted in substantial media attention about the use of artificial nutrition and hydration (ANH) especially by percutaneous endoscopic gastrostomy (PEG). In this article, I review ethical and legal principles governing decisions to choose or forgo ANH at the end of life, including issues of autonomy and decision-making capacity, similarities and differences between ANH and other medical treatments, the role of proxies when patients lack decision-making capacity, and the equivalence of withholding and withdrawing treatment. Evidence for palliative or life-sustaining benefits for ANH are reviewed in three disease processes: amyotrophic lateral sclerosis (ALS), cancer, and dementias, including Alzheimer's disease. Although more recent studies suggest a possible palliative role for ANH in ALS and terminal cancer, feeding tubes do not appear to prolong survival or increase comfort in advanced dementia of the Alzheimer's type.