US Army Medical Research and Materiel Command Heat Stroke in the Military Population

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US Army Medical Research and Materiel Command
Heat Stroke in the Military Population
George W. Weightman Major General, Medical
Corps Commanding General 22 October 2008
https//mrmc-www.army.mil/
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BRIEFING TOPICS

• WE ARE A NATION AT WAR
• HISTORICAL PERSPECTIVE
• THE WAR ENVIRONMENT
• CURRENT WAR ENVIRONMENT
• PREVENTIVE MEDICINE DOCTRINE
• HEAT STROKE IN TODAYS US MILITARY POPULATION

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U.S. Army Research Institute of Environmental
Medicine (USARIEM)

• USARIEM Mission
• Conduct research to sustain / enhance performance
  (physical cognitive) minimize medical
  problems during military operations at
  environmental extremes of heat, cold, high
  terrestrial altitude.
• Support Military Materiel Developers (clothing,
  equipment, food pharmaceuticals) Health
  Hazard Assessments regarding thermal hypoxic
  stress.
• Thermal Mountain Medicine Division
• Core Areas
• Cold Stress Physiology
• Heat Stress Physiology
• High Altitude Physiology
• Environmental Illness (Cold Heat Injury
  Mountain Sickness)
• Hydration
• Research Topics
• Acclimation Acquired Tolerance
• Exposure Guidelines / Decision Aids
• Environmental Injury / Illness Susceptibility
• Hydration Nutrition
• Performance Optimization

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WE ARE A NATION AT WAR

• Protection of our soldiers against heat stroke is
  critical to military success

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HISTORICAL PERSPECTIVE

• Heat stress and illnesses have caused profound
  and catastrophic consequences on military
  operations from biblical to modern times
• US Army heat stroke hospitalization rates
  increased gt7-fold over the past 20 years (Carter
  2005)

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THE WAR ENVIRONMENT
Wars are Fought Outdoors with Extended Exposure
to Harsh Environments and Exhaustive Work
A soldier fighting is not as simple a situation
as an athlete running a marathon. The soldier is
exposed to the environment not knowing for how
long, with minimal food and water. The soldier
suffers tremendous sleep deprivation, fear, hard
work and exposure to heat and cold. The
Scientist, 2004
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Heat Stress Has an Operational Impact
Within initial 72h of battle, 10 of engaged
infantry (40 cases) were evacuated and treated
for dehydration at BAS. Battle of Najaf, Iraq
(August 2004) 1LT Dean Stulz, 1-5 CAV, Battalion
PA (After Action Brief)
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CURRENT WAR ENVIRONMENT
That summer an average soldier on an 8-10 hour
mission drank from 2-4 gallons (8-16 qts) of
water, and another half gallon (2 qts) during the
remainder of the 24-h period while back on
base. SFC Larry Larson, Summer Iraq Operations
(email, 4 April 2005)
BAGHDAD WEATHER USA Today, Tuesday 8 August 2006
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Rate of Heat Stroke / Injury Among Active Duty
Army, 1 Jan 2000 - 30 Apr 2008
Rate of Heat Stroke / Injury Among Active Duty
Army, 1 Jan 2000 - 30 Apr 2008
Current as of 30 April 2008
Data Source Defense Medical Surveillance System
(DMSS) Prepared by Armed Forces Health
Surveillance Center (AFHSC), as of 26-JUN-2008
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Long-term Effects of Heat Stroke?

• Soldiers hospitalized for heat stroke
  subsequently had increased mortality (2-4 fold
  within 30 years) from cardiovascular, liver, and
  kidney diseases.
• Wallace et. al., Environ. Res., 2007

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PREVENTIVE MEDICINE DOCTRINE
http//www.usariem.army.mil/
http//chppm-www.apgea.army.mil/heat
http//www.armymedicine.army.mil/index.cfm
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The Doctrine is Effective and We Are Operating
Effectively
USA Today, Tuesday August 8, 2006
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Heat Stroke Heat Exhaustion Cases Before
After Heat Mitigation Intervention
CPT Erik J. Bergeson APA-C DMO Ranger Training
Brigade Surgeon (Briefing of November 2006)
2002 Before Heat Mitigation Interventions by
USARIEM 2003-2006 After Heat Mitigation
Interventions by USARIEM
YEAR(S) of Classes of Students Heat Stroke Cases Heat Exhaustion Cases
2002 11 2,658 35 (1/75 students) 42 (1/63 students)
2003-2006 38 11,964 15 (1/797 students) 24 (1/498 students)
gt 10-fold decrease
8-fold decrease
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HEAT STROKE IN TODAYS US MILITARY POPULATION

• Continues to be a major problem for US forces
• Non-deployed soldiers in 2007
• 329 incident cases of heat stroke
• 1,853 incident cases of heat exhaustion
• Fort Bragg 7 Nov 07 - 8 Oct 08
• Heat Stroke
• 92 cases of heat stroke
• 137 soldiers on restrictions (8 Oct 08)
• Heat Exhaustion
• 66 cases of heat exhaustion
• 45 soldiers on restrictions (8 Oct 08)
• Heat illness/stroke related restrictions
• US soldiers may be non-deployable for over a year
• Israeli and French soldiers are reevaluated at 6
  to 8 weeks
• The return-to-duty/play issues you will be
  discussing are critical to military success

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