Heat-Related IllnessesHeat-Related Illnesses

David D. Ellis, DO, MPHDavid D. Ellis, DO, MPH

Fellow, American Academy of Fellow, American Academy of Family PhysiciansFamily Physicians

Odessa Regional Medical CenterOdessa Regional Medical Center

June 10, 2008June 10, 2008

Heat-Related IllnessesHeat-Related IllnessesStatisticsStatistics

Average 200 deaths each year in the U.S.Average 200 deaths each year in the U.S. 33rdrd ranked cause of death among U.S. high ranked cause of death among U.S. high

school athletesschool athletes Mortality rates from 15-75%Mortality rates from 15-75%

Heat-Related IllnessesHeat-Related IllnessesCausesCauses

Temperature + Humidity + Sun Exposure + Temperature + Humidity + Sun Exposure + Wind + Clothing (ENVIRONMENTAL)Wind + Clothing (ENVIRONMENTAL)

Body production of heat (ACTIVITY)Body production of heat (ACTIVITY) Heat Illness happens when :Heat Illness happens when :

ENVIRONMENT + ACTIVITY ENVIRONMENT + ACTIVITY overwhelm the body’s capacity to cool overwhelm the body’s capacity to cool itselfitself

Heat-Related IllnessesHeat-Related IllnessesRisk FactorsRisk Factors

Physical Conditions – fever, dehydration, Physical Conditions – fever, dehydration, medicines (antihistamines, water pills, medicines (antihistamines, water pills, cardiac medications)cardiac medications)

Older age – Decreased ability to cool bodyOlder age – Decreased ability to cool body Overweight – more heat generated and less Overweight – more heat generated and less

capacity to dissipate heatcapacity to dissipate heat Younger age – decreased ability to sweat; Younger age – decreased ability to sweat;

higher core temp required to sweathigher core temp required to sweat

Heat-Related IllnessesHeat-Related IllnessesRisk FactorsRisk Factors

Additional factors :Additional factors :* Lack of access to air * Lack of access to air

conditioningconditioning * Sleep deprivation* Sleep deprivation* Previous heat * Previous heat

strokestroke * Heavy * Heavy Clothing/EquipmentClothing/Equipment * Not * Not acclimated to the hot weatheracclimated to the hot weather

Heat-Related IllnessesHeat-Related IllnessesHow does your body respond to heat??How does your body respond to heat??

Core temperature goes UP Core temperature goes UP Blood Blood Vessels DILATE Vessels DILATE SWEATING occurs SWEATING occurs

High Humidity High Humidity LESS heat loss by LESS heat loss by evaporation from the body evaporation from the body Core Core temperature goes UPtemperature goes UP

Heat-Related IllnessesHeat-Related IllnessesHeat Index ChartHeat Index Chart

Heat-Related IllnessesHeat-Related Illnesses

Heat EdemaHeat Edema – MILDEST – leg swelling – MILDEST – leg swelling Heat CrampsHeat Cramps – Muscle spasms, Water – Muscle spasms, Water Heat SyncopeHeat Syncope – Dizziness/Fainting; cured – Dizziness/Fainting; cured

by lying down; by lying down; SWEATINGSWEATING Heat StrokeHeat Stroke – MENTAL CONFUSION – MENTAL CONFUSION

* Core temp > 104.9; * Core temp > 104.9; No SweatNo Sweat* RAPID COOLING * RAPID COOLING

MANDATORYMANDATORY * 10% Death Rate* 10% Death Rate

Heat-Related IllnessesHeat-Related IllnessesTreatment in the FieldTreatment in the Field

Remove unnecessary clothingRemove unnecessary clothing Spray water + FANSSpray water + FANS Ice to armpits/groin/neckIce to armpits/groin/neck Cool water immersion – be carefulCool water immersion – be careful HYDRATE – 1 QUART per hour minimumHYDRATE – 1 QUART per hour minimum

* COLD water to drink cools * COLD water to drink cools internallyinternally

Heat-Related IllnessesHeat-Related IllnessesPREVENTIONPREVENTION

Assess the ENVIRONMENTAL conditionsAssess the ENVIRONMENTAL conditions Proper clothing – light color, thin fabricProper clothing – light color, thin fabric HYDRATION:HYDRATION:

* PRE-hydrate – 16 oz before activity* PRE-hydrate – 16 oz before activity

* 8 oz every 20 min while exposed* 8 oz every 20 min while exposed

* Urine should be light yellow or “white”* Urine should be light yellow or “white” Watch the alcohol, caffeine intakeWatch the alcohol, caffeine intake

Heat-Related IllnessesHeat-Related IllnessesPREVENTIONPREVENTION

Acclimatize:Acclimatize:* Adults – 4-7 sessions in the * Adults – 4-7 sessions in the

heat before acclimatized. Short sessions :heat before acclimatized. Short sessions : (15- 20 min, then lengthen as tolerated)(15- 20 min, then lengthen as tolerated) The body will begin the “ Sweat Early” – The body will begin the “ Sweat Early” –

(think Michael Jordan in the first 2 minutes (think Michael Jordan in the first 2 minutes of a game!)of a game!)

DO NOT wait for thirst to push fluidsDO NOT wait for thirst to push fluids

Heat-Related IllnessesHeat-Related IllnessesSUMMARYSUMMARY

Assess Risk – Identify people at riskAssess Risk – Identify people at risk Acclimatize if possibleAcclimatize if possible Hydrate/Train personnel to recognize Hydrate/Train personnel to recognize

symptomssymptoms Treat with Evaporative Cooling, Immersion, Treat with Evaporative Cooling, Immersion,

FluidsFluids Consider on-site resuscitative equipmentConsider on-site resuscitative equipment

* Automated External Defibrillator* Automated External Defibrillator