Ryanair Initial Practice Exam

What is the time frame for brain death to occur after the brain is starved of oxygen?

1. 3 minutes

2. 5 minutes

3. 10 minutes

4. 15 minutes

The correct answer is: 5 minutes

The correct answer is based on the understanding of cerebral hypoxia, which occurs when the brain is deprived of oxygen. Generally, significant damage to brain cells can begin within 3 to 5 minutes after oxygen supply is cut off. While some symptoms of brain damage may emerge shortly after this period, brain death, which is the irreversible cessation of all brain functions, typically occurs within this timeframe. At around 5 minutes without adequate oxygen, the likelihood of irreversible brain damage increases dramatically. Therefore, the time frame after which brain death is most likely to be categorized is around 5 minutes, marking the point at which interventions are crucial if recovery is to be attempted. Choosing periods longer than 5 minutes may identify delays in significant damage or processes involved in determining brain death, but they do not align with the critical time frame provided by medical guidelines for oxygen deprivation and the onset of brain death.