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swatsurgeon
12-15-2004, 06:59
with the significant increase in suicide bombers I thought this re-newed thread would be appropriate. Previous threads have touched on a few issues related to blast injuries, I wanted to start with a "guide" that was printable as a primer for care of the patient involved in a blast.
This will also hopefully begin a discussion of specific injuries and treatments. Most importantly is recognition of the pending/delayed injuries....the obvious ones are just that, obvious, my concern is the non-observable and how the medic can literally make the difference in the outcome by recognition of the potential problems. Here is the first part or summary then let the questions begin:

Explosion
 This wave of compressed air can be measured as overpressure or direct impulse.
 The magnitude of the overpressure is proportional to the amount and type of explosive used.

Overpressure
 Overpressure is measured in pounds per square inch.
 Relative power is calculated by multiplying PSI X duration in milliseconds of the impulse.
 overpressure of 58 – 80psi is 95% lethal.
 7 – 8psi can shear brick walls or overturn rail cars.
 5psi can rupture tympanic membranes.
 0.5 – 1psi can break windows and knock people down.

Injury Physiology
 Lung injury
– 0-48 hrs to manifest signs/symptoms!!!!!
 dyspnea, cough, hemoptysis, chest pain
 if going to O.R. or air transport, consider chest decompressions
 Ear Injury
 hearing loss, tinnitus, otalgia, vertigo, bleeding, otorrhea

 Abdominal injury
 abdominal pain, nausea, vomiting, hematemesis, rectal pain, testicular pain, shock state, peritonitis
 Brain injury
 concussion / TBI (and associated symptoms), headache, fatigue, reduced concentration, lethargy, depression, anxiety, insomnia, seizures, depressed GCS, pupil changes, weakness, paresthesias

Shock Wave
 The shock wave has 3 components:
– Positive phase
– Negative phase
– Mass air movement

 Positive phase.
– Velocity and duration of the blast head.
 Dependant upon:
– Size/type of the explosive
– Surrounding media
– Distance from the detonation.

Shock Wave
 Closed spaces magnify the effects of the direct impulse.
 “Shock Wave” “bounces” off hard surfaces and is referred to as a “Reflected Impulse.”
Shock Wave
 Shock waves all create similar rates of rise in pressures at the blast front.
 The magnitude of this “positive-phase impulse” becomes the important property in the generation of the Primary Blast Injury (PBI).
Shock Wave
 Negative phase.
– Partial vacuum is created near the epicenter after outward movement of air
– Consumption of oxygen by the burning process.

 The “reflected impulse” may combine with the “direct impulse” and increase injuries at a greater distance from the blast site than expected.

Shock Wave
 Effects are cumulative.
 Example:
– A blast that causes a 1% mortality when experienced once, causes a 20% mortality when experienced twice, and 100% mortality if experienced three times.

Primary Blast Injury
 Caused by shock wave from explosion
– tissues are disrupted at air/fluid interfaces in a process called “spalling”
 ears and lungs are most commonly injured
 bowel injuries more common with under water blasts
– degree of injury is related to the magnitude and duration of the peak overpressure of the blast shock wave
– death nearest to blast is usually caused by massive cerebral & coronary air embolism


Secondary Blast Injury
 Caused by debris set in motion by shock wave that impacts the body

Injuries - Penetrating
 Secondary blast injuries
– Injuries from devices that contain foreign bodies:
 Nails
 Rivets
 Ball bearings
 Nuts and bolts,
 Etc.
Injuries - Penetrating
 Medically, usually no different than other penetrating injuries seen.
 Complicated by the PBI’s.
 Bone and tissue from suicide bombers may be secondary missiles.
– Aids, hepatitis, etc.

Secondary Missiles
Injuries - Penetrating
 Secondary missiles created by container fragments or added missiles can have velocities of up to 1,500m/sec.
 Rapid deceleration seconday to poor ballistic properties.

Tertiary Blast Injury
 Displacement of victims body to crash into other objects

Injuries
 Tertiary injuries – Blunt trauma.
– Physically thrown through the air and strike or impale themselves on objects.
– Collapsing structures.
– Other objects propelled through the air striking the victim.

Tertiary Injuries
 Severe head injury is a leading cause of death in victims of blasts.
 Subdural and subarachnoid hemorrhages are the most common findings in fatalities.

Injuries
 Thermal injuries
 Primary or secondary incendiary.
– Inhalation
– Dermal

Scene
 Recent studies suggest the PBI victims do poorly when strenuous physical activity follows significant blast loading.
– Reduce activity of potential blast-exposed individuals.
– Provide history of activity to ED personnel receiving patient.
Medical Management
 On site treatment is VITALLY important
– rapid stabilization
– control of hemorrhage
– splinting of fractures
– cleaning and covering of wounds
 antibiotics
 analgesics
 med control contact
 transport initiation
Medical Management
 On site treatment is VITALLY important
– immediate determination of concomitant radiation, chemical or biological contamination
 decon if possible
– patient and you
Tactical Field Care
 CPR is not initiated if no signs of life
– no respirations
– no palpable pulse
– no response to any stimuli
 naso-pharyngeal airway is airway of choice for unconscious patient
 Severe respiratory distress = need for chest needle decompression
Tactical Field Care
 Controlled bleeding without signs of shock don’t need IV fluid
– controlled bleeding & in shock = 250-500mL NSS boluses
– uncontrolled bleeding & in shock, but mentating, no IVF
 if depressed mental status, give bolus

 Antibiotics for abdominal wounds

Guy
12-15-2004, 07:35
Thanks for the refresher SS.

QRQ 30
12-15-2004, 08:14
Good info!!

The armor situation has been riden ad nauseum by the press but I would think that the vast majority of casualties from IEDs are from blast and not fragmentation. All of the light armor in the world isn't going to stop the effects of blast. :eek:

Razor
12-15-2004, 08:39
Depending on the grade of armor, installation and type of explosive used, you could get significant fragmentation from interior face spalling. Bad day in anyone's book.

rudelsg2
12-15-2004, 16:17
Actually, the uparmor does work against both (shrapnel and overpressure). This UAHMMWV took a HUGE IED blast just 200m north of the old team house in Samarra on the big Nov 30 fire fight last year. All three soldiers substained minor injuries (which our 18D treated), with the Plt Sgt returning to the fight. The 240 gunner up top received the worst injury, but he was still RTD.



Most soldiers who die from IED attacks are dying from blunt trauma head injuries, this is what killed our Tm Sgt Kelly Hornbeck. He was in a unarmored Land Rover when a IED sent a piece of shrapnel through the windshield impacting his helmet and causing his helmet to deform inward causing massive trauma to the brain.

52bravo
12-18-2004, 04:20
swatsurgeon:
tx for the post. I am making a PowerPoint for a class on blast injuries, what is you ref. On the post.

And do anybody know of good place to get medical pic. From? I find it hard to get medical pic of war injuries. I only have my own from iraq, and what i can get from friends.

The Reaper
12-18-2004, 09:38
Most soldiers who die from IED attacks are dying from blunt trauma head injuries, this is what killed our Tm Sgt Kelly Hornbeck. He was in a unarmored Land Rover when a IED sent a piece of shrapnel through the windshield impacting his helmet and causing his helmet to deform inward causing massive trauma to the brain.

K-Pot, MICH, or something else, if I might ask?

TR

rudelsg2
12-18-2004, 12:45
TR, it was a MICH.

52bravo
12-18-2004, 12:57
TR, it was a MICH.

what it his helmet?

QRQ 30
12-18-2004, 13:18
Nothing will be universally effective but I think additional armor is being overplayed by the press. Land mines, IEDs and demolitions ambushes have been around for centuries. It seems that the media only recently discovered they exist. I can only speak from personal experience of 30+ years ago but I don't think things have changed that much. The VC used shaped charges and B-40 rockets. The B-40 penetrates 40 inches or more of reinforced concrete. Nothing but the most sophisticated armor was safe against it. The defense was stand-off --- chain-link fencing causing the round to detonate before getting to the target.

Most of what I see is blast, to include the damage in the above picture. Improperly installed armor inside the vehicle will also become shrapnel in the event of a blast. IMHO Iraq/ Afghanistan is sitting in the midst of the greatest armor factory in the world -- SAND!! I believe a layer of sandbags on the floor board of a vehicle could be just as effective as pieces of scrap metal. Probably more effective. Sandbags not only stop or slow down projectiles but also dissipate a lot of the effects of blast.

The solution to IED ambushes has to be vigilance, and knowledge due to proper training.

The Reaper
12-18-2004, 13:32
TR, it was a MICH.

Damn.

I am sorry to hear that.

Looks like a pretty big piece moving pretty fast. Not much you can do about it on the personal protective gear side.

RIP.

QRQ, I have to agree with you.

The RPG has been around since the PanzerFaust. We should have already found a better countermeasure for it.

TR

rudelsg2
12-18-2004, 14:15
I don't want to see this great thread get highjacked about armored HMMWVs but since it went that way.


Nothing will be universally effective but I think additional armor is being overplayed by the press.

I totally agree. You make do wioth what you have UNTIL Uncle Sam gives you the proper tools for the job. But, I'll talk about my experience gained on our last rotation. We had all unarmored GMV's, Land Rovers and Hiluxs. We still executed our missions in an IED, RPG heavy area. Our main ally was Speed, keeping the enemy off balance by changing our routes and mostly LUCK. But, after a while your luck runs out. We got lucky with three near misses and then Kelly got hit. We still executed missions after his death. We didn't receive UAHMMWV until after he was killed and we were on our way out. I believe if we had had the Uparmored Hummer, Kelly would be alive today. But people die in combat and that's the way it is.


Most of what I see is blast, to include the damage in the above picture. Improperly installed armor inside the vehicle will also become shrapnel in the event of a blast.

Yes, alot is blast, but alot is shrapnel, an IF this had been our ODA in our GMV's with no armour we all would have been dead. Look at the rear door's ballistic glass, if this had been us, one of our heads would have been missing. The TC would be dead due to the fact the windshield frame would have been completely blown in on him and the fragments not stopped by that ballistic glass in the TC door, he would have eaten that also.




IMHO Iraq/ Afghanistan is sitting in the midst of the greatest armor factory in the world -- SAND!! I believe a layer of sandbags on the floor board of a vehicle could be just as effective as pieces of scrap metal. Probably more effective. Sandbags not only stop or slow down projectiles but also dissipate a lot of the effects of blast.


The UAHMMWV I talk about are PROPERLY armored vehicles not the ones with sheet steel added that don't really stop anything anyway. Yes, sand bags work real well. We sandbagged the hell out of our compound and they absorbed alot of rocket, RPG and mortar rounds when we took hits. But you can't sandbag your GMV into a bunker and still drive around and a layer of sandbags in the floor work well if you run over anti-personnel mines, but not for AT mines. Most IED injuries come through the door and windshield not the floor board.

When you hit a AT mine in a HMMWV it usually flips it over and now the sandbags are on top of you. 10th Group had a UAHMMWV hit 2 AT mines stacked on top of one another in Kosovo in 99' and only one guy was killed in that vehicle. That vehicle was flipped over and the soldier actually died from head trauma (no seat belt or helmet) and not the blast or shrapnel.


The solution to IED ambushes has to be vigilance, and knowledge due to proper training.

I keep hearing this from people who haven't been there. Sometimes there's nothing you can do but hope your actions and the enemies actions are not on the same time line, unless you have armor to get you through that intial blast.


Take this how you want. By all means if anyone doesn't believe you need UAHMMVWs in a HOSTILE URBAN enviroment, then I suggest you go to the Sunni Triangle and drive around it for 5 months in an unarmoured vehicle and then drive around in an uparmored one and see which one takes a little less toll on your nerves at the end of the day. In the end the Uparmor isn't about INVINCIBILITY it about SURVIVABILITY.

I've driven around the cities in the Sunni Triangle in an unarmored GMV with nothing but a MICH, ballistic goggles and BALCS body armor between me and the next IED around the curve. I've also seen first hand the outcome of both IED aftermaths in unarmored and armoured. I'll take the armor.

That's my experience.

**edited to correct some spelling mistakes**

QRQ 30
12-18-2004, 15:48
OK Rudelsg let's keep this a friendly discussion. I know I wasn't there. Believe it or not we all have or had or will have our wars to fight. I wasn't referring to the UAHummv. I was referring to the media making a big thing about troops rummaging through trash piles to find scrap metal to reinforce the floor boards.

I agree with Rumsfeld: you go to war with what you have, not with what you wish you had. R&D is constantly 5 to 10 years ahead of production. I'd bet Cearar's legionaires would have loved to have Hummvs.

I have seen a presentation of IEDs. I am wondering if a barrage frequency generator/transmitter could be used to pre-maturely detonate the devices.

Cool off and let's tip a few. :munchin

rudelsg2
12-18-2004, 20:24
QRQ30, please don't take this as a heated discussion as the written word on the internet doesn't allow the true tone of a conversation and can be misinterpeted. But, I'm a pretty matter of fact guy and that's how I discuss things, so sometimes I come off kind of "gruff".

I was referring to the media making a big thing about troops rummaging through trash piles to find scrap metal to reinforce the floor boards

Gottcha and I know where your comming from. When our guys starting doing the "Joe Dirt" armor applique to the GMVs, our team didn't because the stuff didn't add any protection from IEDs and it just slowed down our GMVs (speed was our greatest friend , there and gone before they knew you were there).

I agree with Rumsfeld: you go to war with what you have, not with what you wish you had. R&D is constantly 5 to 10 years ahead of production.

I agree with this point also, I lived thru the Clinton era military (insert Shelton "Do more with less" mantra here) and saw the US ARMY get bled dry from the Bosnia and Kosovo rotations while budgets were cut (there's a reason why we had a national budget surplus). This is why the main manufacture has had to ramp up production from 15 UAHMMWV a month to 450. There was a excellent brief on the armor issue on C-SPAN this week, very informative. Fortunately, we have the right people from the JCS to the Commander in Chief who will and have gave this military what it needs to fight and win the shooting wars we are now in.

I'd bet Cearar's legionaires would have loved to have Hummvs.

I'm sure the Romans would have, if they had been around and especially if the Carthaginians had had IEDs. ;)

I am wondering if a barrage frequency generator/transmitter could be used to pre-maturely detonate the devices.

I have seen the presentation of this kit, I won't go into specifics on it here, but while it offers a narrow usage anti-IED tool, it also has quite a bit of negative aspects to friendly forces also.

Sits back and takes a draw off the keg-o-rator. :munchin

**edited to correct some spelling errors**

QRQ 30
12-18-2004, 20:42
Yup!! Speed and unscheduled and small targets. I was occasionally on a jeep or 3/4 making a run between Kontum and Pleiku. We went "pedal to the metal". The VC were probably so occupied rolling around laughing at us bouncing down the dusty road that they didn't have time to activate an ambush. Besides there were bigger fish to fry -- 4th ID convoys. :munchin

I know what you mean about non- face to face communications. Hell, sometimes I scare myself when I hear a recording I have made on the phone.

Merry Christmas to all!!!

DoctorDoom
12-23-2004, 00:45
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swatsurgeon
12-23-2004, 15:47
DD,

PBI (pulmonary blast injury) - Lung
 Pulmonary contusion
– Worse on side of approach of blast waves in open air.
– Bilateral and diffuse when victim is located in confined space.
 Degree of pulmonary pathology is proportional to the velocity of chest wall displacement.

 PBI to lung is referred to as blast lung.
 Greater incidence in confined spaces
 Major cause of death in PBI’s
 Alveolar membranes torn
 Minimal to massive hemorrhage with hemothorax or air emboli

 Treatment similar to Pulmonary Contusion.
 Studies have shown no long term effects
 Generally normal after 1 year
PBI - Hypotension
 Bradycardia and hypotension without hemorrhage.
– Blast loads directly at the chest cause a unique vagal nerve-mediated form of cardiogenic shock without compensatory vasoconstriction.
– Occurs within seconds and resolves over 1 – 2 hours.
PBI – Arterial Air Embolus (AAE)
 Hemopneumothoraces, traumatic emphysema, and alveolovenous fistulas from stress-induced tears of air-tissue interfaces.
 Lead directly to bronchopleural fistulas or Arterial Air Embolus (AAE).
PBI - AAE
 AAE to the brain or head may be the most common cause of rapid death caused solely by PBI in immediate survivors.
 May be precipitated by positive-pressure ventilation (PPV).
 Often occurs at the moment of PPV.

52bravo
12-26-2004, 14:23
hi swatsurgeon

what is REFERENCES, ther is a lot of new things in the post i have to read up on.
u must make a book som day.

one Q: can a BVM make a AAE in a blast lung?


Frank Hansen

52bravo
12-26-2004, 14:25
the txt link dont work?
F

swatsurgeon
12-27-2004, 09:30
sorry, here is that pressure/injury curve again...
as far as references......that will take some digging time but I'll try to put something together.

SF West
12-27-2004, 23:39
This is a very good thread!
Great topic!
Have you ever heard of or treated broken bones from the shockwave of a blast?
It seems with the concussive force that is emitted from such explosives like IEDs, Mines, RPG's, and other mixed explosives, that they could easily break bones with the shockwave if they go off relatively near someone.

I once had an opportunity, or rather, responsibility to treat a compound fracture.
It was on a boy scout outing and we were rappeling, this guy was heading down the face and dropped way too fast for about the last 15 feet. His calf snapped in half and was protruding from his skin. We got the leg relatively straight and immediately applied pressure to stop the bleeding. We stopped the bleeding fairly quickly, but were ill prepared to set or mend the fracture at all, we made a migshift stretcher and carried him down the mountain (Mt. Si). We then drove him to the nearest hospital. He was just fine. It took him a good long while to heal and at times now he still has a limp. Sucks for him.

Just thought I'd mention that, first aid has been something I've been interested in.

The tactics being used for these explosives is becoming ever more intelligent, i.e.,
soldiers get out of a vehicle after a IED goes of, a second goes off injuring the soldiers. With an enemy growing more intelligent, the role of the medic and combat surgeon are more vital than ever. And for those of you who are Medics or Trioge doctors, I bow to you, for you have all my respect for your integral role in this nations military.

DoctorDoom
12-31-2004, 12:31
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