Mechanisms of the special neurologic destruction caused by blast injuries

This is absolutely thrilling:
“Bioengineers identify the cellular mechanisms of traumatic brain injury; New hope for treatment of TBI in veterans wounded by explosions”

These scientists discovered the answers to two frustrating questions that have been blocking effective treatment of blast-related head injuries (TBI, or Traumatic Brain Injuries.)

1. What happens to the brain’s axons? Why do the vital communication-arms of the brain’s nerve cells just disappear?

2. Why does TBI from explosions cause the brain’s blood vessels to shut down and turn themselves off, even though the the injury doesn’t seem that bad?

The horrific health cost to our soldiers on active duty has included being blasted by explosives. These cause profound and persistent brain injuries that seem too severe for the amount of shock experienced by the brain.

1. The axons are part of an interlocked structure that’s woven together by cells and intracellular “glues.” This structure is shaken apart by explosive shock. Axons have to release their connections and shrink, retreating into the body of the cell. This destroys the physical functional structure of the brain. The person instantly loses memories and processing power, as well as a pervasive host of brain tasks.

2. The vessels undergo a mechanical stretch caused by the explosive force pushing through the gelatinous mass of the brain, and then, as a result of that stretch, they become super-sensitive to the chemical messenger that tells them to snap shut and then stop acting like vessels at all.
Normally, #2 only happens in the case of severe hemorrhagic (that is, bleeding) stroke. However, we now know that it also happens in blast injuries that otherwise cause less apparent damage.
Clinical note: Blast injuries to the brain are uniquely insidious. They cause diffuse injury that’s invisibly disabling and incredibly hard to manage, let alone recover from significantly. Behavioral issues and so forth are mechanically and chemically imposed on the soldier’s brain; they are not wilful choices on the soldier’s part.

A lot of fundamental retraining has to be done, because emotional, cognitive and social skills have to be significantly rebuilt and rewired. The wiring that the soldier has built on since childhood has been torn up on duty.

Thanks to our present understanding of neuroplasticity, there’s hope and a path to develop, but it takes time. On top of psychological trauma and the damage that causes to the amygdala and sometimes the hippocampus, it’s a hell of a lot for any layperson to grasp, let alone try to handle.

One of the truly thrilling things about these findings is the discovery of a process that keeps the axons from pulling back in the first place. At present, it works in a Petrie dish if given within 10 minutes of injury; hard to see how that could work in combat.

If it could be formulated to be used in a person, it would still have to be administered extremely fast. Maybe send each soldier out with an inhaler of the stuff? Or a nose spray? A 50-cent bottle apiece to save millions in treatment, lost wages, cost of care, incidental costs on the family, for each injured soldier. Seems like a bargain!


Why premature birth shouldn’t be iatrogenic

I’m delighted to get my hands on an article about a study done by a nurse. Prof. Sullivan, RN and her team say, “Effects of premature birth can reach into adulthood.”

Do you know why this is, logically, a candidate for the Department of the Blitheringly Obvious?

It has to do with fetal development. In a healthy pregnancy (that is, most of them), labor starts when the fetus’s lungs — the last thing to finish developing — are done. Then the fetus signals the mother’s body, and labor begins.

The neurological system and heart are getting the finishing touches in those last few weeks, too. The final stages of fetal development are extremely important, and ever more so as it gets harder and costlier to get care in this country.

Why does getting care matter? Aren’t preemies a lot easier to deliver?

They pop out faster, yes. They also tend to need time in the neonatal ICU.

But wait, there’s more.

This article goes on to say that premature babies tend to have lifelong problems with — you guessed it — heart, lungs, and neurology. Neurological issues that consistently show up relate to coordination; learning (especially math); memory; and, most worryingly, hypothalamic-pituitary adrenal (HPA) axis problems — which messes up the body’s ability to regulate weight, growth, anxiety, sleep, and mood; it’s a major factor in CRPS, MS, and other constitutional illnesses.

These people are far more likely to require extra care and attention from parents, school, doctors, nurses, and therapists of both body and mind, _throughout_their_lives_ — or at least, as Prof. Sullivan has shown, to the age of 21. More data to follow, as the study continues.

This is why I find “elective c-sections”, which are often done at 37 weeks just to avoid the final stage of pregnancy, so appalling. They combine the drawbacks and long-term effects of prematurity with those of nonvaginal delivery and abdominal surgery. A full house, you might say.

Back to this article, which focuses on people who were born 21 years ago, when prematurity was not optional.

She states that these personalities tend to be more driven and success-oriented. On the one hand, that could be the cortisol talking (remember the lack of regulation? These people have higher than normal cortisol levels.) On the other, these are all people who have had a higher than average level of care, attention and structure in their young lives, and that tends to produce these characteristics anyway. When young people internalize the message that there are a lot of capable adults who really care what happens to them, they don’t see failure as anything but learning how not to do it next time. And that’s a setup for success.

Having explicated her stated finding, I have to say that she did not, nor did I read anything here about how she measured these personality characteristics. In short, it’s possible she was looking for ways to make everyone feel better about the learning disabilities and systemic issues.

And that, frankly, is one of the common characteristics of nurse studies that tend to lessen the respect they otherwise deserve: nurses who achieve worldly success don’t get there without being good at making decision-makers feel good.

I looked for the text of the study at her site, but no luck. I’ll look on PubMed once I’m off this handheld. I’d like to clear up that last gratuitous silliness, if I can.

* Can’t find it on PubMed. It was published very recently, so it might be worth checking back.