Article

A Thoracic Mechanism of Mild Traumatic Brain Injury Due to Blast Pressure Waves

Department of Physics, United States Military Academy, West Point, NY 10996, United States.
Medical Hypotheses (Impact Factor: 1.15). 01/2009; 72(1). DOI: 10.1016/j.mehy.2008.08.015
Source: arXiv

ABSTRACT The mechanisms by which blast pressure waves cause mild to moderate traumatic brain injury (mTBI) are an open question. Possibilities include acceleration of the head, direct passage of the blast wave via the cranium, and propagation of the blast wave to the brain via a thoracic mechanism. The hypothesis that the blast pressure wave reaches the brain via a thoracic mechanism is considered in light of ballistic and blast pressure wave research. Ballistic pressure waves, caused by penetrating ballistic projectiles or ballistic impacts to body armor, can only reach the brain via an internal mechanism and have been shown to cause cerebral effects. Similar effects have been documented when a blast pressure wave has been applied to the whole body or focused on the thorax in animal models. While vagotomy reduces apnea and bradycardia due to ballistic or blast pressure waves, it does not eliminate neural damage in the brain, suggesting that the pressure wave directly affects the brain cells via a thoracic mechanism. An experiment is proposed which isolates the thoracic mechanism from cranial mechanisms of mTBI due to blast wave exposure. Results have implications for evaluating risk of mTBI due to blast exposure and for developing effective protection.

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Questions & Answers about this publication

  • Wei Zhao added an answer in Brain Trauma:
    Can brain trauma be caused due to thoracic pressure surges?

    I am a mechanical engineer studying mechanisms of brain trauma. Of the mechanisms that I have studied, I found the evidence of brain trauma as a result of thoracic pressure surge only due to blast waves. I would like to know if any other kind of impact in the thorax could lead to brain trauma due to thoracic pressure surge. For eg. if someone gets kicked in the thorax portion are there any chances of their experiencing brain trauma.

    Wei Zhao · Dartmouth College

    This concept is what I learned in my advisor's class. I was not able to found a reference for it. However, I found another paper which could be helpful.

    Based on this Thoracic mechanism as discussed in the following paper, one experiencing a blast wave around chest like the blast from airbag could sustain brain pressure-induced injury.