Friday, September 26, 2014

Sir Isaac Newton, Trauma Junkie?

Lately, I’ve been dreaming about trauma. In my spare time, I’ve been doing ride-alongs with Aircare, the EMS helicopter based out of Orlando’s level 1 trauma center, just to get a taste of my former life as a paramedic. (Does it make me a bad person to wish for a critically injured patient?) You could say I've had trauma on the brain.

To me, trauma is the most exciting realm of emergency medicine. Traumatic injuries can result from a variety of scenarios, from crashes to falls to shootings and stabbings. But they all have one thing in common: physics. Let’s explore.

We’ll begin with a quick trip back in time… It’s the mid-1600s and a less-than-stellar student named Isaac Newton is attending Cambridge University in England. We’ve all heard the story: he’s reclining under an apple tree when suddenly, out of the blue, he is bonked on the head by an errant piece of fruit. The blow to his noggin results in his epiphany that gravity exists, that it can help explain the motion of planets, and that, if an object has enough mass, it can do serious damage to one’s head.

OK, I made that last bit up. In fact, the whole story is fairly bogus. Yes, young Newton supposedly observed an apple fall to the ground (no mention of head injury), which may have triggered contemplation of the moon’s orbit. However, it took him years of study, informed by the works of Descartes, Galileo and Kepler, to develop what would become some of the most important and impactful discoveries of motion and light.

So what does any of this have to do with traumatic injury? A lot, it turns out.

It wasn’t so much Newton’s theories on light and gravity that would influence trauma medicine some four hundred years later (although anyone who has taken a tumble knows the inherent drawbacks of gravity). It was his later work on motion, which he handily summarized in three laws, that would elucidate the drama of trauma and its devastating effects on the body. Since you’re probably not interested in the mathematics behind Newton’s laws and the thought of explaining quantum mechanics is enough to send me screaming, we’ll simply explore the basics of the three axioms and how they relate to the treatment of trauma patients.

Law number one: A body in motion remains in motion unless acted upon by an outside force. Say you’re driving along one night when suddenly you veer off the road and strike a tree. In compliance with Newton’s first law, if you were travelling fifty miles per hour, so were your internal organs. Your car strikes the tree, your body, if unrestrained, then strikes the steering wheel, and your internal organs slam against the confines of your body (brain against skull, heart against ribs - you get the picture). Each impact has consequences for the body’s tissues. This is why seatbelts are so important. Seatbelts provide a mechanism for keeping you from impacting the inside of the vehicle when it is brought to a sudden stop. Yes, seatbelts can do their own damage at high speeds, but I’d take a seatbelt injury over a steering wheel to the chest any day.

Law two: Acceleration is the result of force acting upon mass. According to Newton, the greater the mass, the greater the force needed to move it and the greater the force, the greater the acceleration. Think about our collision – car vs. tree. The heavier our vehicle, the greater the force needed to stop it (especially at high speeds) and the larger and heavier the object we strike (for instance, a massive oak), the greater the impact. Had the tree been a small sapling and our vehicle a compact, the impact would have been minimal. Which leads us to the third law.

Law three: To every action, there is an equal and opposite reaction. Once again, in our collision we were travelling fifty miles per hour, which means that the tree we struck will push back with the equivalent force of fifty miles per hour of speed. Thus the motto, “Speed kills.” How much better off we would have been had we been putting along at a snail’s pace. High speed impacts have devastating effects on the body. The breaking of bones, the shearing of vessels, and the subsequent bleeding that results from these injuries make trauma patients some of the most complex to manage, since any - and many! - body systems can be involved.

Thanks to Newton, we can make predictions as to the types of injuries that will result from traumatic events. Whether it’s an auto accident, a shooting, or a fall, if we know the speed of the vehicle, the caliber and velocity of the bullet, or the height of the fall, we can infer the potential damage inflicted upon the body. Thus, the “mechanism of injury” is one of the fundamentals of trauma assessment and it all originates with the genius of Newton.

Could Newton have imagined the impact his work would have on trauma medicine? Perhaps… The 17th century was a period of dramatic discoveries in science and medicine. The year 1628 saw the publication of Harvey’s An Anatomical Study of the Motion of the Heart and of the Blood in Animals, which detailed his groundbreaking work on the cardiovascular system (although he scores no points for brevity of title); Frenchman Jean-Baptiste Denis and others were tinkering with blood transfusions and slowly refining their techniques - dog to human simply didn’t work. And Leeuwenhoek would perfect the microscope, under which he would discover blood cells and microorganisms (along with the creepy-crawlers inhabiting his own dental plaque). In this climate, it would seem natural for Newton to appreciate the impact (no pun intended) of his laws on medicine.

And if he actually was hit on the head with an apple, surely he could envision the carnage, had that apple instead been a cannonball.

Thanks for reading and don't forget to share!

Here's an absolutely ridiculous video about mechanism of injury, in case you have some time to kill...

Thursday, September 11, 2014

Thirteen Years...

The sun has lost its outline
As I wash the weary skies
The quarter moon ascends the slope
Where on its back it lies

Among the woods the cedar pines
Begin their sweet release
And buried in their needled brow
I’ve come to find my peace.


Friday, September 5, 2014

Taking a Breather...

Damn, life is complicated. As many of you know, I’m in the throes of a major life change. I’ve quit my job as an archaeologist, sold my beautiful little house in Cocoa, and next week I’ll head to the lush hills of Tallahassee to hunt down a place to live. I’ll also be teaching a course I’ve never taught at Florida State University, so I'm using this time off to prepare for my return to academia. Life was much simpler as an archaeologist - who knew unemployment could be so time-consuming?

With all these changes in the mix, writing a weekly post has become quite a challenge. When I was working as a public archaeologist, tucked in my cozy office in front of a computer, the blog was part of my daily routine and I would parcel off a bit of my afternoon for research and writing. My reward? Over forty-six thousand page views, to date. But now that I have no routine (as well as no office) and am pulled in numerous directions, it’s become harder to devote the time needed for thoughtful, well developed posts. So I’m taking a breather.

After posting each week for the past year and a half (seventy-eight and counting!), I’ve found that the most recent posts are not always the most read. Thanks to key words and Google searches, I have found the back posts are just as popular as more recent additions. Therefore, I’m confident The Body Blog will continue to be read, even in the absence of weekly contributions. This would be a great time for you, the reader, to delve into the blog’s archives, for we’ve covered a wide range of topics about the human body.

My background as a former firefighter-paramedic turned bioarchaeologist has provided a broad and unique perspective on the body and the myriad ways it is impacted by culture. We’ve explored such topics as capital punishment, body art, dental mutilation, and embalming. We’ve traveled back in time to explore the evolution of the bra, the condom, cremation, and the kiss. The body’s systems have provided endless fodder and we’ve investigated just about every orifice and appendage, from vaginas and penises to the heart, belly, nose, and brain. We’ve covered the realm of sex: its evolution, selection, our development, and the convoluted history of syphilis. We’ve also delved into the darker side of anatomy, from quackery and grave robbing, to autopsies and necrophilia. Whatever you can do to or with a body, we’ve touched on over the last eighteen months; even the ephemeral realms of empathy and exploitation, the shame of disfigurement, and the power of a mother’s love.

So as I take time to realign my life, I hope you'll peruse some of the older posts. I’ll still add to the blog, just not at the frenetic pace of the past year and a half, and we’ll continue to explore the fascinating entity that is the human body, together.  

Catch you later. And thank you so much for reading.