Image from triggison.com
I think my first real amazement in med school may have been learning about the nephron. Don't ask me to recount it in detail; that part of my brain has long since been emptied and refilled with concern about fiber and bladder trabeculations (another good med-school word.) Looking at it one way (a perverse way?) the essence of medical school is the building of a sense of wonder at the complexity and beauty of the human body, and the essence of becoming a surgeon is the realization of how breakable and disposable it all is.
If you follow the link I made to the word (I sometimes hesitate to link to Wikipedia, given its, er, vulnerabilities, but this one seems OK), you can see what a marvel the nephron is: tubules coming and going, membranes, feedback loops, regulatory perfection. It's but a small example. The brain and its corpora and olives; the endocrinata. Muscles and mitochondria. And wow: the liver. It's simply astounding. Whereas the amount of new information raining down during those years is more than enough to swamp even the most absorbent mind (and notwithstanding the sense of dooming of the looming), it's impossible not to be thrilled and exhuberated by the glimpses you get of the wondrous workings of the human body.
And then you're in an operating room, staring deep into a stellate smash of livid liver. It oozes discontinuous destruction. Fragments of hepatic mush are strewn and coddled among clots of blood, stained with bile and mixed with stool. The beauty of the enzyme pathways is nowhere to be seen; Dr. Krebs is not in the building. Weak indeed is the capsule holding it all in, split apart like broiled bratwurst. How little it takes!
Grey bits of brain on a stretcher in no way reflect the neatness of neurotransmitters, or of ions flashing across axons. A hand, with its marvelous pulleys and cables, when rent apart by a saw or a slash, looks frail and helpless and pathetically flimsy.
There are times, when driving, or riding my bike, when wielding a knife in or out of the operating room -- or just breathing! -- that I suddenly think of how tenuous it all is, how easily smashed and torn apart is this wonderful work of nature in which we find ourselves. It's gelatin; it's a paper bag. I don't suppose the thought is unique to surgeons, or even health-folk in general. But we get a damnably intimate view, and there are times when it haunts me.
Cinch your seatbelt, tighten the shoulder harness, keep two hands on the wheel. Wear a helmet. And for God's sake, look both ways when you cross the street.