Monday, December 04, 2006
Surgeons and Sweetbreads
The good news is most of us will never have a reason to find out. The bad news is we all walk around with a self-destruct button in us, and I'm not getting all Freudian here. Of all the vital organs, there's only one that can -- sometimes with only the slightest of provocations -- turn on us and literally become our worst nightmare: it can eat us alive, from the inside. All the while, doing only what it thinks it's supposed to do.
Operating on the average person, this organ is hard to see, let alone get to. In someone healthy and maybe overly skinny, you can sometimes get a surprising view: delicate, fluffy and pink, demurely lying behind a shiny film that in the rest of us is more opaque. Looking at it, you'd never guess how destructive it can be. In that ideal patient, it looks like something you'd like to rest your head on. No wonder it's called "sweetbreads."
"The normal pancreas is firmer than normal," is what a professor of mine liked to say. He was right: in manually exploring the abdomen, there might be a tendency to think you've found a problem, discovering a rubbery-firm pancreas. It looks (when you can see it) like it ought to be softer. Maybe in the uber-normal, it is. Maybe it routinely gives itself a little trouble more often than we know. In any case, the pancreas is an organ of brooding and explosive mien, no matter how it looks or feels.
In any anatomic drawing, in order to show the pancreas it's necessary to leave something out. Here's an example:
You get the idea of the fluffy pinkness; you don't see the stomach or the colon, because those organs, seen from the front, cover up the pancreas, which lies crossways across the very backside of the abdominal cavity. Operating on it, in other words, can be challenging on the basis of anatomy alone. Add in inflammation, a few digestive enzymes, and tissue not really ideally textured for holding a stitch, and you've got tough surgical sledding. But I'm getting ahead of myself.
If you want details, here's a place to start. The basics are these: the pancreas does two important and unrelated things. First, it produces insulin which controls blood sugar levels, and diminished levels of which cause diabetes. Insulin is secreted by the pancreas directly into the bloodstream (that's the definition of an "endocrine" gland.) Second, it makes several digestive enzymes, which flow through ducts and exit into the intestine (that's what "exocrine" means.) The drainage end of the pancreatic duct joins the draining end of the bile duct (which carries bile from the liver into the intestine); that juxtaposition is important in a bad way, pancreatically speaking. It looks like this:
The complicated anatomy within and around the pancreas, in another context, provides surgeons -- especially surgeons in training -- a cornucopia of delight: removing the head end of the pancreas provides a little bit of everything a surgeon does. I've mentioned all that previously here and here. In its other iteration -- the center of an awful inflammatory process -- that anatomy is nothing but trouble. To give you an idea: we used to keep a sterile ladle, of the sort you'd use in a tasty soup, on hand in the OR to scoop out the stinking soapy detritus of acute pancreatitis. I mean that quite literally: add certain activated pancreatic enzymes to the fat in the area, stir in a little calcium salts, and you get saponification. Soap. Wash behind your belly-button, kids.
What we're talking about here is inflammation of the pancreas, "pancreatitis," which comes in two basic forms (acute and chronic) and has three main causes (no self control, no control, and no clue.) That last triumvirate is wordplay I just made up. It refers to alcohol, gallstones, and "idiopathic." Skimping on detail, suffice it to say that excessive drinking, especially of the binge type can severely damage the pancreas. With gallstones, it helps to look at the above diagram again: imagine a gallstone passing from the gallbladder and lodging at the very far end of the bile duct. Under that circumstance, bile may be forced backwards into the pancreas. That's the likely cause of "gallstone pancreatitis." As for the last category, it's sort of a waste-basket diagnois for "it could any of a number of things, and we may never know."
Some of the sickest patients I've ever cared for are those with the complications of acute pancreatitis, and their surgical needs are as daunting and taxing as it gets. Those with surgical issues related to chronic pancreatitis can sometimes actually be sort of fun. And now, I think I've done enough exposition. In the next post I'll get to the surgical stuff.