Anne Heche suffers from anoxic brain injury. How does that affect the body?

Actress Anne Heche attends the WIN Awards at Santa Monica Bay Womans Club on December 11, 2013 in Santa Monica, California.

Actress Anne Heche has been on a ventilator and is not expected to survive after her car crashed into two houses last Friday, her family told Deadline.

Heche, 53, has been hospitalized since the accident, where she reportedly speeded in her blue Mini Cooper and crashed into one house and then another, with the second going up in flames.

She is suffering from an anoxic brain injury. How does that affect the body?

Anoxic Brain Injury
Anoxic brain injury occurs when all oxygen is cut off from the brain. After about four minutes without oxygen supply, brain cells begin to die, according to the Shepherd Center, a private, nonprofit hospital in Atlanta.

Hypoxic Brain Injury
Hypoxic brain injury occurs when there is a partial limitation of oxygen to the brain. That restriction causes gradual damage and death to brain cells.

Causes of Brain Injury
Brain injuries don’t necessarily originate in the brain. They can be caused by any physical trauma that affects the body’s ability to absorb oxygen, such as a stroke or trauma to the lungs.