Environmental Conditions

1
Environmental Conditions

• NATA Heat Illness Position Statement
• Hyperthermia
• NATA Fluid Replacement Position Statement
• Hypothermia
• NATA Lightening Safety Position Statement

2
Heat Gain/Loss

• Metabolic heat production
• Conductive heat exchange
• Convective heat exchange
• Radiant heat exchange
• Evaporative heat loss

3
Heat Illnesses

• Dehydration
• Exertional Hyponatremia
• Heat Syncope
• Heat Cramps
• Heat Exhaustion
• Heat Stroke

4
Dehydration

• lt2 BWL can hinder performance, often unavoidable
• gt3 BWL increases risk of heat illness
• Fluid intake should fluid loss
• Weight chart/urine specific gravity to monitor
• Sports drink may promote fluid consumption
• Within 1-2 hours post-exercise

5
Exertional Hyponatremia

• Def low blood-sodium levels
• Et overconsumption of H2O without adequate
  replacement of Na which can cause cerebral
  and/or pulmonary edema (can result in death)
• Sxs HA, vomitting, swelling of extremities,
  inc. urine output with dec. specific gravity
• Rx do not hydrate!, transport to ER
• Prevention dont overhydrate, calculate sweat
  rate

6
Heat Syncope

• Fainting due to prolonged exposure to heat/lack
  of acclimatization to heat
• Et peripheral vasodilation of superficial
  vessels in an effort to cool body
• Sxs dizzy, nausea, fainting
• Rx place in cool environment and replace fluids

7
Heat Cramps

• Muscle spasm due to excessive water loss
  (sweating) that causes an imbalance b/w H2O and
  electrolytes (esp. Na)
• Rx fluid replacement (esp. sports drinks),
  stretching, IM
• Prevention replace water and electrolytes after
  all activities, educate athletes

8
Heat Exhaustion

• Collapse due to 1-inadequate replacement of
  fluids lost through sweating/urine output and 2-
  inability to sustain adequate cardiac output
• Sxs profuse sweating, pale skin, mildly elevated
  core temp (100-103), ataxia, HA, dizziness,
  hyperventilation, rapid pulse
• Rx replace fluids (IV?), cool environment,
  elevate legs, remove excess clothing

9
Heat Stroke

• Sudden collapse with LOC due to thermoregulatory
  failure that constitutes a life threatening
  medical emergency
• CNS abnormalities and tissue damage due to
  increased body temperature
• May result in organ tissue damage or death

10
Heat Stroke

• Most impt CNS dysfunction (LOC,
  convulsions..) core temperature of 104 or
  greater
• Other Signs and Symptoms
• Hot and wet OR dry skin
• Shallow breathing
• Rapid and strong pulse (160-180bpm)
• BP seldom rises, may drop
• Increased respiratory rate

11
Heat Stroke

• Rx FIRST PRIORITY?DECREASE TEMP (remove
  clothing, cool setting, cold water bath, fan),
  then transport (EMS), replace fluids (IV)
• Prevention (for all heat illnesses)
  acclimatize, proper hydration/electrolytes,
  adequate rest in shade, monitor environmental
  conditions, educate staff, screen athletes for
  previous hx, monitor weight loss, adapt uniforms

12
Some Risk Factors

• Dehydration
• Uniforms (helmets, dark colors, heavy mat.)
• Illness, h/o heat illness
• Obesity (more metabolic heat production)
• Deconditioned athlete
• Poor acclimatization
• Sickle cell trait (dec. O2 carrying capacity)
• Environmental factors (temp, relative humidity)
• What is one of the best predictors not listed
  here??

13
July NATA News

• WBGT standards need to be adapted for different
  climates
• Documents need to have a disclaimer
• Documents are meant to serve as flexible
  statements that can be modified as necessary

14
August NATA News

• WBGT?gold standard, 1500
• Wet bulb measures humidity
• Dry bulb measures ambient temp
• Black globe measures radiant energy from sun
• gt82 degreeshazardous conditions
• Humidity is key factor
• Currently collecting data in the south

15
PreventionProper Hydration

• 2-3 hrs prior?17-20 oz. H2O or sport drink
• 10-20 prior?7-10 oz. fluid
• Every 10-20 during?7-10 oz. fluid
• 2 Purposes
• decrease rate of hyperthermia
• maintain athletic performance

16
Rehydration Protocol

• Complete within 2 hrs post-activity
• Goal replace any fluid lost
• Educate athletes/coaches
• Calculate sweat rate to encompass all factors
• Most important consideration
• Must reassess after acclimatization
• Sweat rate will increase

17
CHO Hydration

• If exercise session longer than 45-50 or
  intense, CHOs during exercise is beneficial
• CHO concentration gt 8 decreases fluid absorption
  
• Ideally, 6-7 CHO concentration

18
Na Hydration

• Increase Na consumption during initial
  acclimatization or activity lasting 4hrs
• Can achieve by salting foods or adding a little
  salt to sports drinks (will stimulate thirst)
• Optimizes fluid palatability and absorption and
  may decrease cramping

19
Rehydration Beverage

• Ideally, should contain
• H2O?to restore hydration state
• CHO?to replenish glycogen stores
• Electrolytes?to encourage rehydration

20
Hypothermia

• Low temps, periods of inactivity, and damp
  clothing can lead to hypothermia
• Wind chill factor increases risk
• Body heat is lost through radiation (vascular
  areas)
• Core temp 77-85 degrees?death is probable
• Cold injuries are due to dec. peripheral
  circulation inter-/intra-cellular ice crystal
  formation
• After rewarming area, skin may blister

21
NATA Lightening Safety Position Statement

• Primary choice for safe shelter is any
  substantial, frequently inhabited building
• Secondary choice is enclosed vehicle with a metal
  roof and closed windows
• Obligation to warn participants and spectators
  alike suggest locations for safe shelter for
  spectators

22
Flash-to-Bang Method

• Begin counting when lightening is seen
• Stop counting when thunder is heard
• Divide by 5 to determine the distance (in miles)
  to the lightening flash
• If count is 30 sec or less (within 6 miles),
  suspend all outdoor/pool activity

23
30-30 Rule

• If the Flash-to-Bang count is 30 seconds or less,
  all individuals should be in a safe shelter
• Wait at least 30 minutes after the last
  lightening flash or thunder strike to resume
  activities

24
Lightening Safe Position

• Crouched on the ground, weight on the balls of
  the feet, feet together, head lowered, and ears
  covered
• Lowers the height of the person and minimizes
  ground contact
• Being the tallest object/near the tallest object
  is the best way to get struck by lightening
• (good idea to avoid being that guy)

25
First Aid Procedures

• 1. Survey the scene for safety
• 2. Activate EMS
• 3. Move victim to safe location, if necessary
• 4. Assess for apnea and asystole
• 5. Assess for hypothermia and shock
• 6. Assess for fxs
• 7. Assess for burns

26
5 Components of a Lightening Safety Policy

• 1. Establish a specific chain of command
• 2. Appoint a weather watcher
• 3. Monitor local weather forecasts
• 4. Identify safe structures or locations
• 5. Define criteria to suspend and resume
  activities

27
Other Things

• 11-12-04, meet in BIGGS ATR
• Read Ch. 29, notes on-line
• 11-19-04, meet in classroom
• Read Ch. 29, posted readings, notes on-line