Hypoxia and Medicine

How long can a person go with an oxygen saturation level of 65 before brain damage?

Public Comments

1. Difficult to answer. People with COPD (emphysema) can go longer at lower levels, but 65% is very low. 15 minutes, 30 minutes, 1 hour??
2. Brain cells are extremely sensitive to oxygen deprivation. If an O2 sat drops to 65% and remains there, without supplemental O2, within 5 minutes there will be the onset of cerebral damage.