Ethical approval
The National Agency approved this study for the Management of Life-sustaining Treatment, which certified that life-sustaining treatments were managed properly (Korea National Institute for Bioethics Policy (KoNIBP) approval number P01-202007–22-006). The KoNIBP approved the observational study of patients ethically based on FDA guidelines following the World Medical Association Declaration of Helsinki. Therefore, we carried out all methods following relevant ethical guidelines and regulations and reported the study results. Sorokdo National Hospital provided the necessary information in accordance with Article 13 of the “Act on Information Disclosure of Public Institutions.” Sorokdo National Hospital obtained informed consent from all participants or, if participants were under 18, from a parent and/or legal guardian. All consent to participate and consent to publish.