Last post we left our heroine with pneumothorax after she got stabbed in the right side of her chest. If you're a writer, you now want to write either a realistic death scene, or a realistic rescue. Here are some basics to remember as you do the latter.
Somehow, you need to get that air out of her chest. Doctors now-a-days will stab a tube into the space below her ninth rib, towards the front—this is called her ninth intercostal space—and suck that air out. They put it in the ninth space (under the ninth rib), towards the front, so they don't hit your liver. That ninth space is actually just below the border of your lung and above your diaphragm normally, but now it's way below the border of her lung since her lung's all shriveled up. Doctors will sometimes wait to get an X-ray to make sure this is the problem before doing this, but if your heroine's clearly dying—her pulse has stopped, or she's turning blue from lack of oxygen—they'll go ahead and do this without waiting for those pics.
Doctors aren't just careful about which space they insert into. They're also careful to insert the needle in the right part of that space: in the bottom half of the intercostal space, but above the rib. There are important blood vessels under the top rib that you want to avoid, so you try to move closer to the top of the lower rib—but there are some collateral blood vessels there, too, so you don't insert right at the border of the bottom rib, but rather a little above. So if you're writing some kind of tragedy, or from the point of view of a medical student messing up for the first time, you could either have them accidentally insert the needle and chest tube into the wrong space, or make them insert too high and burst a blood vessel into the space so now she's filling up with blood on top of air and MAN THAT WOULD SUCK DON'T WRITE THAT. If your heroine's lying on a fantasy battlefield far from medical care, maybe your magical healer can “sense” the air in her lungs and find some makeshift way to suck it out. A needle and a bamboo straw, I dunno.
After you've gotten the excess air out of her chest, you want to close up that hole. If you can, you want to close it up with a valve so air can get out, but not into her chest. Her lung should now be able to expand enough to allow oxygen exchange, even though it's punctured, and now that it's configured in more its normal shape instead of shriveled like a kitchen rag her body can try to close up the gap in her lung by building new cells there. She may need to be on a ventilator, but at least now her lung can expand, even if it's got a little puncture, so your battlefield heroine may survive without the machinery. As you can imagine, a lot's going to depend on the size of the hole in her lung, since every time she breathes in she's letting air into that thoracic space. That's why it's good to have a valve, so air can get out of her chest but not in. If you've gotten all the air out of her chest cavity without complications, her survival goes way up, and while she'll need to rest—too much stress and pressure can make her lung want to collapse again—her body can take it from here.
Now what if we're not talking a nice stealthy little knife between the ribs? What if you got her stabbed with like this GIANT GIANT SWORD that penetrated more than 4 cm and left a HUGE GASH in her lung?
Tune in next time.
All information from Grant's Atlas of Anatomy, Lippincott's Illustrated Q&A of Anatomy & Embryology, Moore's Essential Clinical Anatomy Third Edition, and the January 2010 article by Nishiumi N., et al, on pulmonary laceration in the Annal of Thoracic Surgery. It's med school.