Navigation Links
Blast overpressure is generated from the firing of weapons and may cause brain injury
Date:1/28/2009

The brain may be injured by the noise, which is produced when, for example, an anti-tank weapon (Bazooka, Karl Gustav) or a howitzer (Haubits) is fired. Scientists at the Sahlgrenska Academy demonstrated mild injury to brain tissue. In response to this, the Swedish Armed Forces restricted the number of rounds per day Swedish personnel can be exposed to.

A number of reports, which have appeared during the last few years, have shown that the brain is sensitive to blast. This study determines whether the occupational standards for the highest levels of blast exposure were valid enough to avoid brain injuries. Traumatic brain injury is very common among war veterans from Iraq and Afghanistan and the majority has been exposed to explosions. The soldiers have symptoms of disorders of memory, mental processes, emotion, sleep, speech, vision and hearing. The symptoms may be similar to those of post traumatic stress syndrome, which may be caused by factors other than combat experience.

The Swedish Armed Forces sponsored a study, which has been carried out by scientists at the Sahlgrenska Academy, University of Gothenburg, Sweden. They have examined the effects of noise after the firing of a Haubits, an anti tank weapon (Karl Gustav) and an automatic rifle and by the detonation of plastic explosives underwater. The study was done on anaesthetized pigs and rats.

"We examined the maximal peak level of the blast in the brain transmitted from the blast in the air, as well as, brain tissue changes that were detected with the microscope, says Annette Slj, one of the scientists who conducted the study.

The noise produced by the firing of both the haubits and the anti-tank weapon exceeds the occupational standards for highest levels of blast exposure. The scientists found that the maximal peak levels of the blast were unexpectedly high in the brain, i.e. that skin and bone appeared to protect the brain poorly. The results suggest that the degree of transmission of a pressure wave from air or water to the brain depends on the dominating frequencies in the frequency spectrum of the noise; low frequencies are transmitted considerably better than high frequencies.

The microscopic examination of the brain showed that the blast from certain weapons produces small haemorrhages (bleeding) in the brain tissue and the meninges (lining of the brain). The examination also suggested that blast exposure leads to the development of brain edema, i.e. increased fluid content. The scientists were later able to support this finding with other measurements. The results are in agreement with findings in the brains of soldiers who had been injured or died after being exposed to explosions in wars, from WW1 to the war in Iraq.

In summary, the study shows that the maximal peak levels of blast generated by the firing of certain weapons led to a small but measurable effect on the brains of pigs and rats.

The study also showed that this effect on the brain becomes worse with increasing maximal peak blast levels. The results poses the question as to whether exposure to even lower levels of blast than previous thought injurious might be contributing to the large numbers of mild traumatic brain injuries in American military personnel.

"This is of course an occupational question for Swedish Armed Forces. In light of the results of the study, the Swedish military has instituted restrictions in the number of firing rounds a person is allowed to be exposed to in a single day", says Annette Slj.

Direct studies on humans are difficult to perform, since biomarkers of injury in cerebrospinal fluid or blood and imaging studies such as computed tomography (CT) and magnetic resonance imaging (MRI) do not appear to be specific or sensitive enough to detect mild brain injury.


'/>"/>

Contact: Annette Slj
annette.saljo@gu.se
46-702-240-899
University of Gothenburg
Source:Eurekalert

Related medicine news :

1. Engineered virus targets and kills apparent cancer stem cells in neuroblastoma
2. Childrens cancer group recommends global evaluation system for neuroblastoma to improve treatment
3. The physics of explosives and blast helmets
4. Breast Cancer Vaccine Blasts Some Tumors
5. Experiments could lead to new treatments for neuroblastoma
6. New AMA Ads Blast Senate Inaction on Medicare Cuts That Begin Today
7. Chilean volcano captured blasting ash
8. Researchers find gene location that gives rise to neuroblastoma, an aggressive childhood cancer
9. Researchers Find Gene Location That Gives Rise to Neuroblastoma, an Aggressive Childhood Cancer
10. Gene Variation Linked to Neuroblastoma, a Childhood Cancer
11. Nurses Blast SEIU for Deceit in Hiding Violence at Michigan Conference
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:6/26/2016)... , ... June 26, 2016 , ... ... once they have been diagnosed with endometriosis. These women need a treatment plan ... require a comprehensive approach that can help for preservation of fertility and ultimately ...
(Date:6/25/2016)... ... ... Austin residents seeking Mohs surgery services, can now turn to Dr. Jessica ... Peckham for medical and surgical dermatology. , Dr. Dorsey brings specialization to include Mohs ... Mohs Micrographic Surgery completed by Dr. Dorsey was under the direction of Glenn Goldstein, ...
(Date:6/25/2016)... ... 2016 , ... "With 30 hand-drawn hand gesture animations, FCPX users can easily ... of Pixel Film Studios. , ProHand Cartoon’s package transforms over 1,300 hand-drawn pictures ... . Simply select a ProHand generator and drag it above media or text in ...
(Date:6/25/2016)... ... 2016 , ... As a lifelong Southern Californian, Dr. Omkar Marathe earned his ... David Geffen School of Medicine at UCLA. He trained in Internal Medicine at Scripps ... in hematology/oncology at the UCLA-Olive View-Cedars Sinai program where he had the opportunity to ...
(Date:6/25/2016)... ... , ... On Friday, June 10, Van Mitchell, Secretary of the Maryland Department ... in recognition of their exemplary accomplishments in worksite health promotion. , The Wellness at ... Wellness Symposium at the BWI Marriott in Linthicum Heights. iHire was one of 42 ...
Breaking Medicine News(10 mins):
(Date:6/24/2016)... , June 24, 2016 The Academy of ... recommendations that would allow biopharmaceutical companies to ... entities that make formulary and coverage decisions, a move ... of new medicines. The recommendations address restrictions ... appear on the drug label, a prohibition that hinders ...
(Date:6/24/2016)... PUNE, India , June 24, 2016 ... "Pen Needles Market by Type (Standard Pen Needles, Safety ... 12mm), Therapy (Insulin, GLP-1, Growth Hormone), Mode of Purchase ... published by MarketsandMarkets, This report studies the market for ... is expected to reach USD 2.81 Billion by 2021 ...
(Date:6/23/2016)... June 23, 2016  MedSource announced today that ... e-clinical software solution of choice.  This latest decision ... value to their clients by offering a state-of-the-art ... relationship establishes nowEDC as the EDC platform of ... full-service clients.  "nowEDC has long been a preferred ...
Breaking Medicine Technology: