Palliative Sedation for Existential Suffering: A Systematic Review of Argument-Based Ethics Literature

Context. Although unanimity exists on using palliative sedation (PS) for controlling refractory physical suffering in end-of-life situations, using it for controlling refractory existential suffering (PS-ES) is controversial. Complicating the debate is that definitions and terminology for existential suffering are unclear, ambiguous, and imprecise, leading to a lack of consensus for clinical practice. Objectives. To systematically identify, describe, analyze, and discuss ethical arguments and concepts underpinning the argument-based bioethics literature on PS-ES. Methods. We conducted a systematic search of the argument-based bioethics literature in PubMed, CINAHL, Embase (R), The Philosopher's Index, PsycINFO (R), PsycARTICLES (R), Scopus, ScienceDirect, Web of Science, Pascal-Francis, and Cairn. We included articles published in peer-reviewed journals till December 31, 2016, written in English or French, which focused on ethical arguments related to PS-ES. We used Peer Review of Electronic Search Strategies protocol, Preferred Reporting Items for Systematic Reviews and Meta-Analyses, and The Qualitative Analysis Guide of Leuven for data extraction and synthesis of themes. Results. We identified 18 articles that met the inclusion criteria. Our analysis revealed mind-body dualism, existential suffering, refractoriness, terminal condition, and imminent death as relevant concepts in the ethical debate on PS-ES. The ethical principles of double effect, proportionality, and the four principles of biomedical ethics were used in argumentations in the PS-ES debate. Conclusion. There is a clear need to better define the terminology used in discussions of PS-ES and to ground ethical arguments in a more effective way. Anthropological presuppositions such as mind-body dualism underpin the debate and need to be more clearly elucidated using an interdisciplinary approach. (C) 2018 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.