Saturday, March 28, 2009

Heads Up (Marin IJ)

Heads Up

Several years ago, while working at a county hospital, I treated a patient with an unusual head injury. The young man was with his girlfriend, in the midst of a heated argument, when he abruptly exited her vehicle, while it was traveling at highway speed. He hit the asphalt, head first, and rolled off the freeway. In the Emergency Department (ED), an hour or so later, he was seemingly unfazed by the incident. The only external signs of trauma were some scrapes and an eggplant-like lump over his temple. I was surprised at how good he looked, considering that he’d jumped out of a moving car, but also suspicious. I sent him over for a CAT scan of the head (Head CT) and, by the time he returned, he was nearly comatose. I looked in his eyes and saw that one pupil was twice the size of the other, a sign that his brain was being badly squeezed.

I thought about this patient recently as I was reading of the tragic death of actress Natasha Richardson. Richardson, for those who have been in news hibernation for the last six weeks, died last month after falling on a beginner’s ski slope. Richardson and my car-ditching patient each developed an epidural hematoma – a blood collection in the epidural space between the skull and the brain. Epidural hematomas, which are a relatively rare type of head injury, are usually caused by a fracture of the temple (temporal bone) and bleeding from the artery beneath it. In both these instances, the bleeding ballooned, compressing the brain like a pinched grape. The important difference between the two cases was that my patient, unlike Richardson, was transported by ambulance to a trauma center with an in-house neurosurgeon – who whisked him to the operating room.

The delay in transferring Richardson to a trauma center was one of several aspects of her story that received significant media attention. Some of this media exposure was helpful – alerting the public to the warning signs associated with severe head injuries. Take, for example, the seven year-old girl in Ohio who complained of a horrible headache two days after being struck in the temple by a batted baseball. Her parents, who were watching coverage of the Richardson story on CNN, brought her to the ED just in time to receive treatment for an expanding epidural hematoma.

Some of the media coverage, on the other hand, was less helpful. One online article stated that clot busting drugs might be used to treat a blood collection in the brain, which, in actual fact, would cause more bleeding and be a very bad idea. Another advised head injured patients be seen at a trauma center – which is a good plan for someone who has taken a header off the roof onto the driveway – but not necessary for most head bonks. Others repeated the myth that head injured patients be woken up every hour at night, a practice that accomplishes only one thing – a poor night’s sleep for everyone involved. And finally, a rather alarmist blog advised that all patients with head trauma be screened with a Head CT. It seems as though some folks are taking this advice seriously – in the last few weeks I’ve evaluated a handful of minor head injured patients who have requested a Head CT. This may seem reasonable until you consider that about 90% of Head CTs ordered for trauma patients are completely normal and that they involve significant doses of radiation that may be harmful, especially to the developing brain. So, how does a doc decide who needs a CT and who can go home radiation-free?

Fortunately, researchers in the U.S. and Canada have developed a number of research-based guidelines that are extremely accurate in ruling out head injuries that require surgical treatment. For example, the Canadian CT Head Rule, derived from a study of over 3000 adults with a symptomatic head injury (confusion or amnesia at the time of trauma) is 100% accurate at predicting which patients are safe without a CT. The full details of the rule are too lengthy for this column, but essentially they boil down to this: you need a CT if you have any of the following: age greater than 65, repeated vomiting, persistent confusion, or evidence of a skull fracture (like an eggplant over your temple or clear fluid draining from your nose).

Of course, I’m not suggesting that you try to evaluate yourself with these guidelines at home. I just want you to know that if you hit your head and go to the ED and your doctor says that you don’t need a CT, he or she has probably used a proven tool to help make this decision.

Aside from the importance of appropriate evaluation and treatment of head injuries, there’s another important take-away from the Richardson tragedy. And that has to do with prevention; wearing a helmet is nearly 100% protective against epidural hematomas. Now, a helmet cannot protect against severe brain shaking or bruising, such as might occur in a car accident, but it can shelter you from direct trauma to the temporal bone. This is why baseball players wear helmets while at bat (the first major league player ever killed on the field - Ray Chapman- was an unhelmeted batter struck in the temple by a pitch). And this is why 21 states and numerous municipalities have made it mandatory for children to wear helmets while riding their bicycles (helmets are 85% effective in lessening the severity of head injuries from bike crashes.) I am not arguing that we all walk around wearing helmets, that would make for a lot of bad hair days, but perhaps people learning a high velocity sport, like skiing, should be advised to. As for jumping out of cars, helmet or no-helmet, this is not a recommended activity. My patient did well after surgery, but I don’t imagine he will be trying that stunt again.