I asked this question, specifically about pneumonia, as my professor and I walked out of class. Part of the difficulty, I think, is that it's not a simple event. Intuitively, a massive invasion of foreign organisms doesn't seem like it can be a good thing. But to actually outline the steps until death -- pathophysiology, if you'd like to put a name to it -- is much more difficult. Which organs are most affected? What are the proximal causes that actually make these organs fail?The professor explained that the inflammatory exudate floods the alveoli to such an extent that breathing becomes labored. But, I insisted, can't you just aspirate out the fluid? If we know what's happening to a person's lungs, can't we just fix it?
The answer, of course, is that it's not that easy, antibiotics aside (and antibiotic resistance is a whole other story). Once the inflammation response is at full strength, the influx of cells, cellular debris, and protein into the lungs results in a complete loss of lung architecture such that the normally air-filled lungs actually take on the consistency of the liver.
I still couldn't wrap my head around it. And it will probably be awhile before I do. Because really, it's not just an intellectual difficulty in understanding the process; it's also a psychological difficulty in really comprehending how a body that functions, sustains a living individual, can become one that is lifeless. Humans know what death is from a young age, and have some exposure to it; but really understanding how a person dies is something that comes much later, and much harder. This, I guess, is where the man is who loses a loved one and says, "one minute she was with me, and the next, she was gone."
I know I'll need to wrestle with it some more. And I probably won't really understand it until I have firsthand experience witnessing the end of a life. And maybe not even then.