When does a human being die?

Does Hypothermic Circulatory Arrest for Aortic Surgery Trigger Near-Death Experience? Incidence of Near-Death Experiences after Aortic Surgeries Performed under Hypothermic Circulatory Arrest

BACKGROUND

 Understanding near-death experiences (NDE) could provide a new insight into the analysis of human consciousness and the neurocognitive processes happening upon the approach of death. With a temporary interruption of systemic perfusion, aortic surgery under hypothermic circulatory arrest (HCA) may be the only available model of reversible clinical death. We present, herein, the results of an observational study designed to assess the incidence of NDE after aortic surgery.

METHODS

 We performed a prospective study including consecutive patients who underwent thoracic aortic surgery between July 2018 and September 2019 at our institution. Procedures without HCA were included to constitute a control group. The primary outcome was the incidence of NDE assessed with the Greyson NDE scale during the immediate postoperative course, via a standardized interview of the patients in the surgical ward.

RESULTS

 One hundred and one patients were included. Twenty-one patients (20.8%) underwent nonelective interventions for aortic dissection. Ninety-one patients had hemiarch replacement (90.1%). Sixty-seven (66.3%) interventions were performed with HCA, with an average circulatory arrest duration of 26.9 ± 25.5 minutes, and a mean body temperature of 23.7 ± 3.8°C. None of the patients reported any recollection from their period of unconsciousness. There was no NDE experiencer in the study cohort.

CONCLUSION

 Several confounding factors regarding anesthesia, or NDE evaluation, might have impaired the chance of NDE recollections, and might have contributed to this negative result. Whether HCA may trigger NDE remains unknown.

Waiting for a miracle or best medical practice? End-of-life medical ethical dilemmas in Bahrain

BACKGROUND AND OBJECTIVES

In Bahrain, maintaining life support at all costs is a cultural value considered to be embedded in the Islamic religion. We explore end-of-life decision making for brain dead patients in an Arab country where medical cultures are dominated by Western ideas and the lay culture is Eastern.

METHODS

In-depth interviews were conducted from February to April 2018 with 12 Western-educated Bahraini doctors whose medical practice often included end-of-life decision making. Discussions were about who should make withdrawal of life support decisions, how decisions are made and the context for decision making. To develop results, we used the inductive method of thematic analysis.

RESULTS

Informants considered it difficult to engage non-medical people in end-of-life decisions because of people's reluctance to talk about death and no legal clarity about medical responsibilities. There was disagreement about doctors' roles with some saying that end-of-life decisions were purely medical or purely religious but most maintaining that such decisions need to be collectively owned by medicine, patients, families, religious advisors and society. Informants practised in a legal vacuum that made their ethics interpretations and clinical decision making idiosyncratic regarding end-of-life care for brain dead patients. Participants referred to contrasts between their current practice and previous work in other countries, recognising the influences of religious and cultural dimensions on their practice in Bahrain.

CONCLUSIONS

End-of-life decisions challenge Western-trained doctors in Bahrain as they grapple with aligning respect for local culture with their training in the ethical practice of Western medicine.

Gene expression in the twilight of death: The increase of thousands of transcripts has implications to transplantation, cancer, and forensic research

After a vertebrate dies, many of its organ systems, tissues, and cells remain functional while its body no longer works as a whole. We define this state as the "twilight of death" - the transition from a living body to a decomposed corpse. We claim that the study of the twilight of death is important to ethical, legal and medical science. We examined gene expression at the twilight of death in the zebrafish and mouse reaching the conclusion that apparently thousands of transcripts significantly increase in abundance from life to several hours/days postmortem relative to live controls. Transcript dynamics of different genes provided "proof-of-principle" that models accurately predict an individual's elapsed-time-of-death (i.e. postmortem interval). While many transcripts were associated with survival and stress compensation, others were associated with epigenetic factors, developmental control, and cancer. Future studies are needed to determine whether the high incidence of cancer in transplant recipients is due to the postmortem processes in donor organs.