The problem with head injuries is that much of the damage has already occurred when the patient arrives at the hospital. This primary injury, that is, the injury which occurs at the time of the accident and perhaps in the several minutes that follow, is not generally something that can be prevented except by primary prevention of the accident itself or through public health measures (such as teaching people not to dive head first into shallow water, or designing automobile steering wheel columns so that they collapse in a collision rather than impale the driver through his/her chest—indeed, such impaling was a common cause of death in the cars of the 1960’s and before).
Everything that happens after the initial few moments of an accident can be modified or affected by first responders, EMT’s, paramedics, nurses, and physicians. The goal of these folks is to reduce any subsequent injury, the so-called secondary injury. Indeed, prevention of secondary injury is the holy grail of the trauma system generally, and, in the case of head injuries, the neurosurgeon in particular.
What exactly does this mean?
Here’s an example. Let’s say a little boy climbs a tree, as little boys will. Unfortuantely, this little boy, call him Billy, takes a tumble and falls twenty feet or so to the ground. Billy’s sister, call her Jane, sees the whole thing and rushes to his side. Billy is unconscious, maybe he’s breathing and maybe he isn’t. Maybe his neck is broken. Perhaps he has a punctured lung. His leg is skewed something awful, so that’s probably broken too. And who can say whether or not Billy has internal injuries—a ruptured spleen, torn intestine, etc.
Now, all of these things constitute primary injuries. Everything Jane does from here on out will result in some degree of secondary injury. Some actions will lessen it, others might make things worse.
If his neck is broken, moving it could result in paralysis. This is secondary injury. Even if he is paralyzed, moving his neck could make the paralysis worse.
What about that broken leg? Is there a pulse in the foot? If not, every minute that passes without restoring the pulse results in potential injury to the muscles, nerves, sinew, etc of the leg. This too is secondary injury.
What if Billy is bleeding? If he is bleeding profusely, it must be controlled (stopped) immediately, or Billy won’t make it. Thus, one of the first things a first responder must do is look for and control bleeding. But it’s not the first.
It’s not the first because controlling bleeding in somebody who is not breathing makes little sense. You can win the battle and lose the war in such a moment.
It’s all very confusing at first, but there is an order to these things. Everyone, from trained first responders up the line to trauma surgeons, are taught to follow the ABCs of trauma care:
A—Airway, B—Breathing, C—Circulation, in that order.
A quick glance will often tell if a patient is breathing. If he is, the airway (mouth, throat, treachea) must be reasonably clear, if not check first that the airway is not clogged with teeth, blood, dirt, vomit, etc. These things will need to be removed if they are present. Once clear, does he breathe? Could be the lungs are damaged, or the chest compromised in some way (a punctured lung, for example). Some of these things can be treated on the spot, others less so. Finally, if the patient is breathing, is he circulating blood? Are his fingers and lips blue? Is he bleeding? Profusely?
These are the things which kill immediately or at least very quickly. Of course, the experienced responder does these things more or less simultaneously, followed by a more thorough survey of the patient. It’s all a work in progress though, with reassessment after reassessment after reassessment until the patient gets to a higher level of care.
Then the real fight to prevent secondary injury begins. More on that another time.