IV. Surgery
There are several branches of surgery, subspecialties within a specialty. I was supposed to be on General Surgery, where, depending on the milieu of the hospital system in your region or city, can mean the surgeon does everything, or is basically relegated to operating on things in the belly, on the skin or to wounds. There are likely many other skills included here: endoscopy and central line placement to name a couple.
Then there is trauma surgery...this is what I was reassigned to at the last minute. It is a zero to a hundred miles per hour in a minute job. There is a lot of hurry up and wait, even in a busy trauma center. These folks still do general surgery in their spare time, but when you've been torn up in a car wreck, or stabbed or shot by your homies (or wife, or girlfriend, or best friend, or...you get the point), these are the folks that try to put you together again. The saying "Life over limb," really applies here. They initiate the basics: ABCs as you learn them in Basic Life Support, and carry that forward into skilled placement of emergent central lines and airways, or they may stick a finger in your neck to make a 'dam' in your carotid so you don't bleed out. It is a structured approach to trying to correct chaos. In the moments most human beings would turn tail and run, blood pouring down the sides of the life flight helicopter as it lands, limbs laying next to a person in an obviously non-anatomic position, or someone in agonizing pain, with no obvious external injury, these folks jump in, rub their hands together and get to work.