What are signs of brain injury? Head trauma explained after Bob Saget's cause of death revealed

NEW YORK -- One month after Bob Saget was found dead, his family and the Florida medical examiner's office handling the case announced that the comedian and "Full House" star "passed from head trauma."

"They have concluded that he accidentally hit the back of his head on something, thought nothing of it and went to sleep. No drugs or alcohol were involved," the family statement read.

While deaths from traumatic brain injuries are rare, the Centers for Disease Control and Prevention reports tens of thousands of cases each year.

ABC News Chief Medical Correspondent Dr. Jennifer Ashton joined "Good Morning America" Thursday to explain how head trauma can result in death and share brain injury warning signs.

Robin Roberts: How often does this happen, that a head injury leads to something being fatal?

Dr. Ashton: We have to look at the anatomy of the brain. There are blood vessels there. This is a very unforgiving organ for trauma. It's a closed space: Between the hard skull and the soft brain, a little bit of bleeding can cause compression on the brain, and in some cases, can be fatal.

Roberts: So is this something that is common?

Dr. Ashton: No. But can it happen? Yes.

Roberts: So it's not totally unusual?

Dr. Ashton: We often hear about traumatic brain injuries in sports or in military settings, but people can slip and fall in their own homes. According to the CDC, there are an estimated 1.5 million traumatic brain injuries in the country every year. About 230,000 people are hospitalized each year for this. And unfortunately, in 2019, there were 61,000 deaths due to traumatic brain injury. As we say in medicine, an increased risk of a rare event is still rare. But if it happens to you, it's a big deal.

Roberts: Are there any warning signs or symptoms?

Dr. Ashton: It's important for people to understand that when you talk about the brain, you always want to err on the side of caution. Head injury warning signs are headache, nausea/vomiting, loss of consciousness and confusion. If you have hit your head, you actually want to err on the side of caution. We all minimize our symptoms, and we don't like to bring attention to ourselves. But this is a situation where you want to seek medical attention. You want to get checked out. It is better to be safe than sorry.

Editor's note: The transcript of the interview was edited for clarity.