https://www.medrxiv.org/content/10.64898/2025.12.03.25341583v1 Skip to main content medRxiv * Home * About * Submit * ALERTS / RSS Search for this keyword [ ] [Search] Advanced Search Physician estimates of the feasibility of preserving the dying for future revival View ORCID ProfileAriel Zeleznikow-Johnston, Emil Kendziorra, Andrew T McKenzie doi: https://doi.org/10.64898/2025.12.03.25341583 Ariel Zeleznikow-Johnston 1 Monash University; * Find this author on Google Scholar * Find this author on PubMed * Search for this author on this site * ORCID record for Ariel Zeleznikow-Johnston * For correspondence: arielzj.phd{at}gmail.com Emil Kendziorra 2 European Biostasis Foundation; * Find this author on Google Scholar * Find this author on PubMed * Search for this author on this site Andrew T McKenzie 3 Apex Neuroscience * Find this author on Google Scholar * Find this author on PubMed * Search for this author on this site * Abstract * Info/History * Metrics * Data/Code * Preview PDF Loading Abstract Importance: Terminally ill patients sometimes inquire about preservation procedures (e.g. cryopreservation, aldehyde-based fixation) as end-of-life treatment options, yet physician perspectives on feasibility and ethical acceptability remain uncharacterized. Objective: To assess US physicians' estimates of preservation feasibility, views on interventions to improve outcomes, and positions on ethical and legal frameworks. Design: Cross-sectional survey conducted October 2025. Setting: Sermo, an online platform for verified US healthcare professionals. Participants: Convenience sample of 334 physicians comprising 150 primary care physicians (general practice, internal medicine, family medicine) and 184 other specialists. Main Outcomes and Measures: Estimated probability that preservation retains neurally-encoded information sufficient for future revival; support for pre-mortem anticoagulation and pre-cardiac arrest procedure initiation; views on compatibility with patient-centered care. Results: Among 334 physicians, the median estimated probability that preservation under ideal conditions could retain sufficient neural information for future revival was 25.5%. Overall, 27.9% found preservation somewhat or very plausible for enabling future revival; 47.0% found it somewhat or very implausible. Most physicians (70.7%) supported prescribing anticoagulants to terminal patients to improve preservation quality; 11.7% opposed. For patients choosing preservation in combination with medical assistance in dying, 44.3% supported initiating preservation prior to cardiac arrest; 28.8% opposed. Most (58.1%) agreed preservation could be consistent with compassionate care (20.1% disagreed), and 49.1% reported comfort with patients choosing preservation (30.0% uncomfortable). Familiarity with preservation correlated with higher probability estimates (r = 0.26; p < 10-3), while end-of-life discussion frequency correlated with support for pre-cardiac arrest procedures (r = 0.18; p = 0.003). Conclusions and Relevance: US physicians assigned a median 25.5% probability to preservation retaining neural information under ideal conditions in a manner potentially compatible with future patient revival. The majority support for pre-mortem anticoagulation and substantial support for pre-cardiac arrest initiation indicate that many physicians would consider accommodating patient requests for preservation-enhancing interventions. These findings may inform development of clinical guidelines, though the speculative nature of the estimates warrants consideration. Competing Interest Statement Andrew McKenzie is an employee of Sparks Brain Preservation, a non-profit brain preservation organization, and a director of Apex Neuroscience, a non-profit research organization. Emil Kendziorra is a shareholder and CEO of Tomorrow Bio, a biostasis provider, President of the Board of the European Biostasis Foundation, a non-profit research foundation, a shareholder and director at Oxford Cryotechnology, Inc., a cryopreservation research organization, and a board member at CryoDAO, a Swiss research association. Funding Statement Research funding for this study was supported by a CryoDAO grant (2025.1). Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Pearl Institutional Review Board of Pearl IRB waived ethical approval for this work (#2025-0579). Specifically, the survey and its implementation were reviewed by the Pearl Institutional Review Board and received an exemption determination (#2025-0579) I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Data Availability A list of the survey questions is available here: https://osf.io/ awgk7/files/jn27a The full set of participant response data is available here: https://osf.io/awgk7/files/hrm76 https://osf.io/awgk7/files/jn27a Copyright The copyright holder for this preprint is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. It is made available under a CC-BY 4.0 International license. View the discussion thread. Back to top PreviousNext Posted December 08, 2025. Download PDF Data/Code Email Thank you for your interest in spreading the word about medRxiv. NOTE: Your email address is requested solely to identify you as the sender of this article. 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[Send Message] Share Physician estimates of the feasibility of preserving the dying for future revival Ariel Zeleznikow-Johnston, Emil Kendziorra, Andrew T McKenzie medRxiv 2025.12.03.25341583; doi: https://doi.org/10.64898/ 2025.12.03.25341583 Share This Article: [https://www.medrxiv.org/content/10.64898/2025.12.0] Copy Twitter logo Facebook logo LinkedIn logo Mendeley logo Citation Tools Physician estimates of the feasibility of preserving the dying for future revival Ariel Zeleznikow-Johnston, Emil Kendziorra, Andrew T McKenzie medRxiv 2025.12.03.25341583; doi: https://doi.org/10.64898/ 2025.12.03.25341583 Citation Manager Formats * BibTeX * Bookends * EasyBib * EndNote (tagged) * EndNote 8 (xml) * Medlars * Mendeley * Papers * RefWorks Tagged * Ref Manager * RIS * Zotero * Tweet Widget * Facebook Like * Google Plus One Subject Areas All Articles * Addiction Medicine (496) * Allergy and Immunology (816) * Anesthesia (266) * Cardiovascular Medicine (3932) * Dentistry and Oral Medicine (399) * Dermatology (339) * Emergency Medicine (551) * Endocrinology (including Diabetes Mellitus and Metabolic Disease) (1364) * Epidemiology (14394) * Forensic Medicine (26) * Gastroenterology (1005) * Genetic and Genomic Medicine (5959) * Geriatric Medicine (591) * Health Economics (893) * Health Informatics (3908) * Health Policy (1267) * Health Systems and Quality Improvement (1415) * Hematology (497) * HIV/AIDS (1150) * Infectious Diseases (except HIV/AIDS) (15388) * Intensive Care and Critical Care Medicine (1013) * Medical Education (553) * Medical Ethics (139) * Nephrology (607) * Neurology (5826) * Nursing (312) * Nutrition (883) * Obstetrics and Gynecology (1021) * Occupational and Environmental Health (900) * Oncology (2965) * Ophthalmology (856) * Orthopedics (327) * Otolaryngology (390) * Pain Medicine (382) * Palliative Medicine (113) * Pathology (606) * Pediatrics (1546) * Pharmacology and Therapeutics (626) * Primary Care Research (650) * Psychiatry and Clinical Psychology (4888) * Public and Global Health (8496) * Radiology and Imaging (1977) * Rehabilitation Medicine and Physical Therapy (1232) * Respiratory Medicine (1113) * Rheumatology (535) * Sexual and Reproductive Health (623) * Sports Medicine (481) * Surgery (641) * Toxicology (85) * Transplantation (265) * Urology (233)