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)