Hypothermia Brian & Evan

What is Hypothermia? Hypothermia is a medical emergency that occurs when your body loses heat faster than it can produce heat, causing a dangerously low body temperature. Normal body temp is around 98.6 F (37 C) Hypothermia occurs as body temp drops below 95 F (35 C) https://www.youtube.com/watch?v=beubXiQHLoc

Symptoms of Hypothermia Shivering Slurred speech or mumbling Slow, shallow breathing Weak pulse Clumsiness or lack of coordination Drowsiness or very low energy Confusion or memory loss Loss of consciousness Bright red, cold skin (infants)

Physiology: Temperature Homeostasis Four ways heat is lost: Radiation (65%) Evaporation (25%) Convection (5-10%) Conduction (2-5%) (except in water--- 32x more conductivity in water than air)

Physiology: (Mild Hypothermia) Your Bodies response to heat loss Core Body Temp = 96-97 F - Shivering (not under voluntary control) - Disabled from Complex motor function - Vascular constriction (Toes, Fingers, etc)

Physiology: (Moderate Hypothermia) Your Bodies response to heat loss Core Body Temp = 91.4-93 F Reduced level of consciousness Loss of fine motor function - especially in hands Slurred speech Violent shivering Irrational behavior (taking layers off)

Physiology: (Severe Hypothermia) Your Bodies response to heat loss Core Body Temp = 86-91 F Shivering arrives in waves… Violent intervals The body shuts down on shivering to conserve glucose Casualty falls to the ground..bundles up to conserve heat Muscle rigidity develops because peripheral blood flow is reduced and due to lactic acid and carbon dioxide buildup in the muscles Pale skin Pupils Dilate Pulse decreases At 86 F the body is in state of “Metabolic Icebox” - They look dead, but are still alive

Body Heat Production (Positive Factors) Limit Shivering By: Fitness Fuel Stores (glycogen) Fluid Status Food Intake

Heat Retention + Heat Production < Cold Challenge = Hypothermia Heat Retention = Insulation, Body Fat, Surface to Volume Ratio, Shell to Core Protection Heat Production = Exercise, Shivering Cold Challenge = Temperature, Wetness, Wind

Examples of Hypothermia situations Submerged in cold water (ex. Ice fishing, swimming in superior, canoe) Hiking Skiing/Snowboarding Snowmobiling Car breaks down Sweating, Rain (wet) Wind (Blowing, Moving, Biking)

Immersion Hypothermia Significant risk in waters colder than 25 C and 72 F 0= 32 4=39.2 10=50 21=69.8

https://www.youtube.com/watch?v=5VWQLHOoHa0

Risk Factors Exhaustion Older age Very young age Mental problems (judgement related) Alcohol and drug use Certain medical conditions Medications Shelter

(B) Alcohol MYTH: Alcohol warms your body which can actually help prevent hypothermia Alcohol lowers the core body temperature “Alcohol is a vasodilator, meaning that it causes your blood vessels to dilate, particularly the capillaries under the surface of your skin. Thus, the volume of blood brought to the skin’s surface increases, making you feel warm” Minimizes blood flow to the skin in order to keep core body temperature up Alcohol reduces the body's ability to shiver - yet another method to keep warm

Prevention COLD Dress young kids with extra layer Cover Overexertion Layers Dry Dress young kids with extra layer Fluids and Carbohydrates Bring kids inside as soon as they start shivering Be prepared for any trips in the cold Be smart around water Avoid alcohol

Situational Response Survive a fall through the Ice: Once in the cold water, your body's cold shock response, called the "torso reflex" will make you want to gasp for air and hyperventilate because your heart rate accelerates rapidly, but you must avoid doing so Wears off in 2-3 minutes Keep Calm and DO NOT PANIC Remove any heavy objects Focus Energy on getting out 3-5 minutes before muscle shutdown Get horizontal and kick your legs Let water drain Roll your body across the ice once you're out

Treatment First-Aid Be gentle with the person Get them in a dry, warm location Remove wet clothing Monitor breathing Warm beverage if alert Don’t apply direct heat Medical Treatment Passive rewarming Blood rewarming Warm intravenous fluids Airway rewarming

Resources https://www.mayoclinic.org/diseases-conditions/hypothermia/symptoms-causes/syc-20352682 http://www.firstaidforfree.com/what-are-the-different-stages-of-hypothermia/ https://www.princeton.edu/~oa/safety/hypocold.shtml http://www.climatecentral.org/news/great-lakes-water-temperatures-at-record-levels http://www.kayaksession.com/the-chilling-truth-about-cold-water-immersion/ https://www.mayoclinic.org/diseases-conditions/hypothermia/diagnosis-treatment/drc-20352688 http://www.todayifoundout.com/index.php/2012/10/alcohol-does-not-help-prevent-hypothermia-it-actually-makes-it-more-likely/