Brain Injury Basics: What You Need to Know

March 27, 2009 — -- The recent death of actress Natasha Richardson from a ski accident has many people asking questions about head injuries, and why some can end up producing no more than a bump on the head while others can kill.

Read more: Female athletes suffer from concussions more often than their male peers.

Signs and Symptoms of a Concussion or Head Injury

What are the signs you may have a concussion?

The chief warning signs are confusion, memory loss, headache, nausea or vomiting, blurred vision, slurred speech and balance problems. All of these symptoms do not have to be present, and they can range from mild to severe.

What should you do if you think you have had a brain injury?

If you have lost consciousness from a head injury, seek immediate evaluation at an emergency department. Do not drive yourself to the hospital. The same applies to other serious symptoms such as blurred vision, slurred speech or severe headache. For mild head injuries, be sure to watch the victim closely for 24 hours for symptoms that might develop. If the victim develops any symptoms of concussion, seek medical attention right away.

Dr. Jam Ghajar, a neurosurgeon and president of the Brain Trauma Foundation, answers more questions about brain injuries.

How common is it for what seems like a simple bump on the head to become fatal?

About 1.7 million people each year visit emergency rooms with head injuries, and 90 percent turn out to be concussions. Of those people, about 80 percent recover from the concussion within three months.

The symptoms of a concussion include headache, attention and memory problems. All functions are working, they just seem to be out of sync -- it's really a timing problem. The brain can essentially get whiplash, forming tiny tears in the front of the brain, in the area that controls timing.

About 20 percent of people go on to have problems that include but are not limited to fatigue, irritability and severe headaches. Only a fraction of people die as a result of a traumatic brain injury.

How soon after a head injury can you tell whether you're looking at a mild concussion or something life-threatening?

I get a lot of calls from moms who say, "My kid hit his head. Should I go to the emergency room?" And since kids don't express themselves well, you really have to pay attention to how they're acting.

Is the kid acting normally? If so, and they continue to, it's probably OK. If they are awake, and this is true at all ages, that's a good sign, but make sure they can pay attention. Ask them questions, ask them to follow your finger.

They may be walking around, and they may look OK, but in these serious injuries, what's been affected is the frontal lobe. That doesn't control how you look, it controls your executive processes -- your ability to focus, to understand what's being said to you, to make decisions. So that's what you're looking for.

If someone is vomiting, if there's a seizure, a loss of consciousness or blood coming out of the head, you want to go straight to the ER. If they're feeling suddenly sleepy, go to the ER. Kids can also act squirmy, moody and slur their speech.

Eye dilation is a sign someone is going into a coma. There's a brain bleed that's constricting those vessels.

More Concussion Questions Answered

So why, in some cases, does it take only a single head injury to do so much damage? I mean, think of all of the professional football players whose heads get knocked around week after week for 20 years? And in most cases, they walk off the field alive.

Of course, there are cases where football players can get an injury and be dead in a few hours. In those cases, they are hit from an angle, and the brain can whip around inside the skull, tearing and stretching, which causes a large hemorrhage and they don't get to the hospital in time.

But the ones who get multiple injuries and still walk off the field are getting tiny tears repetitively over time. A leading cause of Alzheimer's disease and dementia is head injuries.

There are plenty of different ways to fall, and different consequences for each. What's the difference between hitting your forehead from a forward fall versus hitting the back of your head on a backward fall?

It's not just the force, it's the way it's applied. In a rotational shearing of the brain from whiplash, you hit the head and the whole brain rotates and causes tears. You can think of it as the brain stretching. Parts of it are moving faster than others, and that stretching causes a tearing of the tissue -- even deep tissue that's responsible for being awake. The fibers in the front part of the brain are most likely to get stretched, and those are the ones that correlate with attention and memory.

The really bad injury comes from being hit on the side. If you're hit in the front, the brain goes back and forth in a linear fashion. If you hit the side of your head, it's more likely to rotate in the dangerous manner I just described. If a woodpecker hit a tree at an angle, it would pass out. That's why it hits the tree straight on.

So what does happen when you're hit straight on?

Can Immediate and proper care at the hospital make a huge difference?

Seventy-five percent of trauma centers now monitor brain pressure. But one out of four don't routinely follow best practices, and we're trying to get this number up. When following best practice guidelines, for example, you want to know that the brain's getting oxygen. If care centers take certain steps, mortality falls by 50 percent.

Immediate care can also prevent a fatality. I strongly encourage everyone to take a CPR course because that is life-saving. ... If there's a lot of pressure in the brain, you're not going to be breathing properly.