BOTTOM LINE UP FRONT (BLUF): Repeated BLAST Exposures (RBE) have negative effects on the human brain. Researchers want to come up with better and faster ways to identify brain injury. And the only non-pharma-based intervention to heal the brain wounds that is available now is not being used: Hyperbaric Oxygen Therapy (HBOT).
We’re deviating from our publishing schedule to bring recent, revealing evidence about BLAST recently published in the Proceedings of the National Academy of Sciences (PNAS): Impact of repeated blast exposure on active-duty United States Special Operations Forces is a multimodal study of active-duty United States Special Operations Forces (SOF)—an elite group repeatedly exposed to explosive blasts in training and combat—to identify diagnostic biomarkers of brain injury associated with repeated blast exposure (RBE).
The study found that higher blast exposure was associated with alterations in brain structure, function, and neuroimmune markers, as well as a lower quality of life. Neuroimaging findings converged on an association between cumulative blast exposure and a widely connected brain region that modulates cognition and emotion.
As we discuss this research and some of its precedents, it is important to keep in mind this chart from as early as 1990. The Textbook of Military Medicine over 30 years ago called for the use of Hyperbaric Oxygenation as “the definitive therapy” in the management of primary blast casualty. One wonders what happened in medicine to reverse course from a definitive treatment to only treating symptoms?
In yet another exposition of a well-known phenomenon, the study informs that United States (US) Special Operations Forces (SOF) are frequently exposed to explosive blasts in training and combat, but the effects of repeated blast exposure (RBE) on SOF brain health are incompletely understood. “In 30 active-duty US SOF, we assessed the relationship between cumulative blast exposure and cognitive performance, psychological health, physical symptoms, blood proteomics, and neuroimaging measures.” As a result, SOF personnel may experience negative cognitive, physical, and psychological symptoms for which the cause is never identified, and they may return to training or combat during a period of brain vulnerability. Furthermore, there is no diagnostic test to detect brain injury from RBE.
[NOTE: the statement “there is not diagnostic test to detect brain injury from RBE” may be technically true, but practically useless when the treatment that is available remains the same. While science may advance with a definitive diagnostic test, the warrior will be left with a standard of care that continues to fail at its primary task: heal the brain wound and restore the patient to near-normal health. The only treatment currently doing that is not used: HBOT.]
This study comes on the heels of data in SCIENCE showing the most detailed map of a cubic millimeter of the human brain. Smaller than a grain of rice, the mapped section of brain includes over 57,000 cells, 230 millimeters of blood vessels, and 150 million synapses. This is a tiny piece of the brain, less than a millionth of the average adult. The human brain consists of 100 billion neurons and over 100 trillion synaptic connections. There are more neurons in a single human brain than stars in the Milky Way! Now imagine the impact on that complexity by hundreds to thousands of blast waves and impacts over a career.
It is those circuits and those neurons and their synapses that are damaged in BLASTs.
“In this cross-sectional study of active-duty SOF personnel with extensive combat experience and blast exposure in Operations Enduring Freedom, Iraqi Freedom, New Dawn, and Inherent Resolve, we acquired cognitive performance, psychological health, physical symptom, neuroimaging, and blood proteomic measures. Our goals were to elucidate the effects of RBE on SOF brain health and inform the design of a diagnostic testing protocol for repetitive blast brain injury (rBBI).”
A board-certified neuroradiologist and neurologist reviewed all conventional brain MRI scans acquired at the study visit. No acute or chronic traumatic lesions were detected for any of the participants. Thus, none of the participants met Veterans Affairs/Department of Defense (VA/DoD) diagnostic criteria for moderate- severe traumatic brain injury (TBI).
Couple that with warrior reluctance to report any form of brain injury for all the reasons they’ve lived: extraction from duty, potential loss of clearances, rotation out of theatre, and more recently, threats that TBI diagnoses have to also include PTSD, a red flag incident. The cards are stacked against reporting invisible injuries, as well, because of lack of available treatment beyond the obvious: reducing symptoms.
The importance of the SPECT images below is found in comparison with scans in the SOF Study. “In 30 active-duty US SOF personnel, higher blast exposure was associated with a decrease in health-related quality of life and brain alterations detected by MRI and PET. What the SPECT images show is the equivalent of brain function restored due to HBOT treatments as recorded by functional measurements of blood flow resulting in heat signatures. More heat equals more blood equals more oxygen, equals more healing.
The authors are candid, but seem wide-eyed at finding the obvious: “Our observations add to growing evidence that rBBI is a pathophysiologic entity that is distinct from single blast-related mild TBI, just as studies suggest that chronic traumatic encephalopathy (CTE) in individuals with repeated sub-concussive blunt head trauma is a pathophysiologic entity that is distinct from single blunt mild TBI.” Translated, this means more head hits are worse than one.
Medicine continues to argue as “unproven” what the data suggest: more hits are bad, ergo, reduce hits. And the list of “blasts” accounted for is the first time this author has seen a fair accounting: They measured lifetime blast exposures to 1) small/medium arms (e.g., rifles, machine guns); 2) large arms (e.g., shoulder-carried rocket-propelled weapon systems); 3) artillery or missiles carried by vehicle, aircraft, or boat; 4) small explosives (e.g., grenades, flashbangs, small improvised explosive devices [IEDs]); and 5) large explosives (e.g., breaching explosives, large IEDs). They also did not measure the myriad exposures experienced by SOF that may affect their brain structure and function, including high- altitude jumping, deep sea diving, inhalation of heavy metal fumes, noise exposure, aircraft vibrations, and g-forces while traveling over tall waves at high speeds, the repetitive whiplashes – in the thousands – experienced by Special warfare combatant-craft crewmen (SWCC).
Clearly, to sustain a reliable and ready force, and to provide the best care on the planet to that force, DOD and the VA cannot continue to run away from promising and proven treatments. Further research on diagnosing brain wounds will only increase the numbers of diagnosed brain wounded.