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TRADOC Surgeon Brief – COL Carolyn Tiffany
Michael N. Sawka, Ph.D.
Chief, Thermal & Mountain Medicine Division
US Army Research Institute of Environmental Medicine
Natick, MA 01760-5007
Arm Immersion Cooling
Briefing Purposes
Background
Science
Status
Decisions
Background
US Army Research Institute of Environmental Medicine
CPT David DeGroot
Dr. Robert Kenefick
Natick Soldier Research, Development & Engineering
Center
Mr. Richard Gallimore
Mr. Henry Girolamo
Arm Immersion Cooling Team
Background
• Heat Stress Degrades Military Performance & Induces
Serious Heal Illness (Heat Exhaustion, Heat Injury, Heat
Stroke)
• Heat Stress Abatement (TBMED 507) Includes Heat
Acclimatization, Hydration & Modifying Metabolic Rate
(Work:Rest) / Clothing / Equipment
• Existing Field Cooling (Water Misting & Showers) Have
Severe Limitations
Problem
Background
• May 2008 - Ft Benning (COL Harry Warren, CMDR MACH)
Requested Heat Stress Mitigation Visit
• Need for Field-Expedient Cooling: Sustain Performance
& Reduce Risk of Heat Illness (MEMO 20 May 2008)
• System Requirements:
• Established Scientific Principles & Effective Cooling
• Low Cost with Minimal Logistical Support
• Transportable & Scalable
• February 2009 - TRADOC (COL Karen O‟Brien) Partnership
• May 2010 - Materiel Developer Identified (PEO-STRI)
• October 2010 - Needs Statements Signed by TRADOC
DCG for IMT & MRMC CG
Background
Funding
• 2008 - 2011: USARIEM (Internal)
• 2008 - 2011: NSRDEC (Internal)
• 2010: TRADOC UFR $130K (Prototype Construction)
• 2011: TRADOC UFR $210K (Prototype Construction)
Science
• Heat Transfer of Water ~25 X Greater than Air
• Forearms Highly Vascularized with Large Surface Area:
Mass Ratio
• Established Efficacy
• Giesbrecht et.al. Aviation, Space & Environmental Medicine 2007
• House. Journal of Defence Science 1998
• Khomenok et.al. European Journal of Applied Physiology 2008
• Selkirk et.al. Journal of Occupational & Environmental Hygiene 2004
Why Arm Immersion Cooling?
Science
House, Journal of Defence Science 1998
40oC 50% RH
~30 min @310 W
Control
30oC
20oC
10oC
Science
Giesbrecht et.al. ASEM 2007
Heat Loss By Area Immersed
Science
Selkirk et.al. JOEH 2004
Severe Heat Stress: 50 min Exercise & 30 min rest with AIC
Control
Mist
Arm Immersion
Science
Post-Exercise in 50°C Environment with ACUs Sleeves Rolled Up
Skin Temperature & Cardiovascular Benefits
(with 2X Greater Core Temperature Drop)
Kenefick (USARIEM Unpublished)
Status
• Assumed Scientific Efficacy
• Approach to Optimize Design • Customer Satisfaction
• Feedback Driven Design Improvement
• Questionnaire
• Not Human Research (MRMC & EAMC IRBs)
• Metrics • Training Improvement (Subjective)
• Heat Illness (Selected Companies; Safety Offices & TRADOC
Opt for Broad Disbursement)
Development Strategy
Status
Generation #1: Steel
prototype AICS at Airborne
School training site (still in
use)
Generation #2: Plastic
prototype AICs on
folding table
Generation #2: Fabric
Prototype AICs with
Collapsible Plastic Legs
Sept „08 – 1 AICS fielded to 1/507th (Airborne School)
• need for more portable design
Spring ‟09 – 2 AICS designs (Plastic & Fabric) fielded to 1/507th, Ranger Training
Brigade, SFAS course
• Preference for fabric vs. plastic & folding legs
Status
Generation #3, fabric, aluminum
frame, lightweight (55 lbs), support
casualties
Ranger Training Using Generation #3
•Spring ‟10 – 60 prototype AICs fielded for evaluation
•Spring „11 – 40 prototype AICs fielded for evaluation
INSTALLATION Unit (Bde) Unit (Bde) Unit (Bde) Unit (Bde)
AICS OH
Dist of New AICS
Total AICS
Remarks # of AICS Units
# of AICS Units
# of AICS Units
# of AICS Units
FT BENNING
192nd INF Bde
198th INF Bde
Airborne Schl
Ranger TNG Bde
44 20 64
75th Ranger Rgmt has 5 AICS
12 9 13 25
FT JACKSON 165 INF Bde 193 INF Bde
7 12 19
10 9
FT SILL
434th FA Bde
0 5 5
5
FT LEONARD WOOD
1st ENG Bde
0 3 3
3
FT KNOX
194th AR Bde
3 0 3
3
FT LEE
23rd QM Bde
4 0 4
4
Status
Prototype AIC Distribution
Status
• 1/507th reported ZERO heat injuries in 2009 at training sites
where AICS was used (historically many)
• Ranger School requested 25 additional units for Camp Darby
• 75th Ranger Regiment, Ft. Jackson safety office, Ft. Knox
safety office, Ft. Benning IET BDE CMDRs want AICs based
on peer feedback.
• “We will take as many of the fabric version as you can give
us. Our goal would be for each platoon to have one. Based
on observations, the more the better. This is because of the
500+ students we have using the AIS. When the students
break, there are long lines at the AIS.”
–SFC Christian, Operations NCO, 1/507th PIR
2009 – 2010 Feedback
Status
2011 Preliminary Feedback
• Ft Jackson (Distributed by Ranges) - Grenade range, Live Fire range,
& FOB site
• Ft Benning (Distributed by Unit) - Airborne School, 192nd IN BDE, RTB
• ALL Sites Support Concept & Continued Use
• Ft. Benning – Sufficiently Well Received that Units Improvised
Solutions for Lack of AIC Prototypes (Coleman coolers)
• Coleman coolers reduces logistical burden but needs improved form
• Logistical Burden (Ice & Water) Needs to be Reduced
• Noted psychological benefit of short break and cooling “re-set their
heads” – CPT Thompson, RTB; LTC Brown 192nd IN BDE
Decisions
• Continue ?
• Critical Needs Statement ?
• Redesign ?
• Evaluation ?
• Funding ?
Back Up Slides
Extra Slides
Skin Blood Flow / Volume & Cardiovascular Strain
During Exercise – Heat Stress
Warm Hot
Tsk = 32ºC
SkBF = 0.5 L/min Tsk = 36ºC
SkBF = > 5.0 L/min
Cheuvront et al, JAP 2003
Metabolic Rate ~450 W; Core Temperature ~37.6oC
Hot Skin Accentuates Dehydration Mediated
Aerobic Performance Degradation
Kenefick et.al. JAP 2010
Tc ~38.0oC Euhydrated
Tc ~38.6oC Hypohydrated
(-3% BWL)
Status
2011: Feedback is Mixed
• 1 /507th Airborne School – “need more & reported heat casualties few
& far between” (MSG Genzlinger)
• A 2-46, 192nd IN BDE – “zero heat injuries since using AICS. We need
more of them” (CPT Young, 1SG Rider)
• B 2-46, 192nd IN BDE – “Evac rates are down, but not worth the
logistical burden” (CPT Barton)
• 2-46, 192nd IN BDE – “Concept is good, need a better design” (LTC
Brown, Battalion CO)
• Unknown unit – support use especially for training new recruits who
don’t know how to self-regulate work/rest and self-monitor (SSG Rowe)
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