Introduction:
Death must be determined according to established medical criteria, which includes either the irreversible cessation of circulatory and pulmonary functions or the irreversible cessation of all brain functions. Brain death/death by neurologic criteria (BD/DNC) is defined as the complete and permanent loss of brain function, including unresponsive coma with loss of capacity for consciousness, brainstem reflexes, and the ability to breathe independently

Objective:
The aim of this review was to establish the differences in the determination of brain death worldwide, as well as the ethical, religious, and legal dilemmas associated with the determination of brain death.

Review methods:
Pubmed and Google Scholar databases were searched using key words. Original articles in English, published between 2015–2024 were included. Articles that did not meet the selected criteria were excluded.

Brief description of the state of knowledge:
Numerous studies have shown that there is variability in the determination of BD/DNC, both internationally and intranationally. This leads to the situation in which a patient may be considered deceased in one location, but not in another.

Summary:
Differences in protocols for determining brain death exist globally, and while efforts towards standardization are underway, certain aspects still require improvement. The endeavour to unify protocols worldwide faces challenges due to ethical and religious disparities. While these protocols offer legal guidance to physicians and may reduce liability, they do not absolve medical professionals of ethical obligations. Physicians must prioritize patient welfare and be confident that brain death criteria are ethically justified and free from external pressures.