KIN 2236 HEAT & HYDRATION QUESTIONS AND
VERIFIED ANSWERS
Exertional Heat Injury - Answers - - 46 high school football players died of heat stroke
between 1995 and 2010
- 5 year period of 2005-2009 saw more exertional heat stroke deaths in organized
sports in the US than any other 5 year period in the past 35 years
Temperature - Answers - - As atmospheric temperature increases, the temperature
gradient between air and body decreases
- When Tbody > Tenvironment, we lose heat via radiation
- Over 27°C the body is 80°F in heat
- Heat loss is from evaporation only
Exercise in the Heat - Answers - - Heat is generated by endogenous sources (muscle
activity and metabolism)
- Exogenous sources (transfer to body when Tenvironment > Tbody)
- When an athlete exercises in a hot environment they sweat to dissipate heat
- An increase in humidity will decrease the vapour gradient, therefore there will be less
evaporation
- + Tbody due to decreased evaporation of sweat
Risk of Exertional Heat Injury - Answers - - We must also take the humidity into
consideration
- Substantial humidity, even at low temperatures can be dangerous
Exertional Heat Stroke (EHS) - Answers - - Occurs when the patient presents with
exertion-related hyperthermia (core body temperature > 40°C) and associated CNS
disturbance or evidence of other end organ system damage
- They may first experience dizziness, weakness, nausea, fast pulse and respiration,
and mental confusion
- They may collapse and suddenly become unconscious
- The individual may stop sweating (hot, dry skin), but this is unreliable
Heat Exhaustion - Answers - - Characterized by an inability to continue functioning in
the heat without evidence supporting diagnosis of EHS (no temperature > 40°C)
- Signs and symptoms are variable and may include heavy sweating with pale, moist,
cool skin, headache, weakness, dizziness, nausea (with or without vomiting)
The Athlete with Exertional Heat Injury: Non-Severe (Heat Exhaustion) - Answers -
Primary (Hard Signs)
- Conscious
- Alert
, - Temp < 40°C
- Systolic > 100 mmHg
Secondary (Soft Signs)
- Sweating
- Pale, moist, cool skin
- Cramping
- Nausea
- May or may not be present
The Athlete with Exertional Heat Injury: Severe (Heat Stroke) - Answers - Primary (Hard
Signs)
- Unconscious or decreased mental status (disoriented or irrational behaviour)
- Temp > 40°C
- Systolic < 100 mmHg
Secondary (Soft Signs)
- No sweat
- Hot, dry skin
- Weakness/flaccid
- Nausea
- May or may not be present
Management of Exertional Heat Injury: Mild Patients (Heat Exhaustion) - Answers - -
Alert with appropriate behaviour, near normal/ stable vital signs, and able to drink fluids
- Care on side-line for up to one hour with up to 2L of fluids
- Rest in the shade, cooling, rehydration, frequent vital signs and mental status
assessment (every 5-10 minutes)
- Upon realization that recovery will require more than this, or if the patient is not
improving, then evacuation to and ER should be quickly arranged
Management of Exertional Heat Injury: Severe Patients (Heat Stroke) - Answers - -
Mental status changes, amnesia, syncope, seizure, unable to drink fluids, unstable vital
signs, or temp > 40°C
- Cool first, transport second
- Care on sidelines includes aggressive cooling within golded first 30 minutes:
- Remove gear
- Ice/water submersion (best) or on core starting with armpits and groin/ fanning,
rehydration
- Frequent vital signs and mental status assessment (every 5-10 mins)
- Quickly arranging evacuation to an ER
- This is life threatening, these patients require immediate evaluation by an experienced
clinician and lab tests
Intrinsic Risk Factors for EHS - Answers - - Lack of acclimatization
VERIFIED ANSWERS
Exertional Heat Injury - Answers - - 46 high school football players died of heat stroke
between 1995 and 2010
- 5 year period of 2005-2009 saw more exertional heat stroke deaths in organized
sports in the US than any other 5 year period in the past 35 years
Temperature - Answers - - As atmospheric temperature increases, the temperature
gradient between air and body decreases
- When Tbody > Tenvironment, we lose heat via radiation
- Over 27°C the body is 80°F in heat
- Heat loss is from evaporation only
Exercise in the Heat - Answers - - Heat is generated by endogenous sources (muscle
activity and metabolism)
- Exogenous sources (transfer to body when Tenvironment > Tbody)
- When an athlete exercises in a hot environment they sweat to dissipate heat
- An increase in humidity will decrease the vapour gradient, therefore there will be less
evaporation
- + Tbody due to decreased evaporation of sweat
Risk of Exertional Heat Injury - Answers - - We must also take the humidity into
consideration
- Substantial humidity, even at low temperatures can be dangerous
Exertional Heat Stroke (EHS) - Answers - - Occurs when the patient presents with
exertion-related hyperthermia (core body temperature > 40°C) and associated CNS
disturbance or evidence of other end organ system damage
- They may first experience dizziness, weakness, nausea, fast pulse and respiration,
and mental confusion
- They may collapse and suddenly become unconscious
- The individual may stop sweating (hot, dry skin), but this is unreliable
Heat Exhaustion - Answers - - Characterized by an inability to continue functioning in
the heat without evidence supporting diagnosis of EHS (no temperature > 40°C)
- Signs and symptoms are variable and may include heavy sweating with pale, moist,
cool skin, headache, weakness, dizziness, nausea (with or without vomiting)
The Athlete with Exertional Heat Injury: Non-Severe (Heat Exhaustion) - Answers -
Primary (Hard Signs)
- Conscious
- Alert
, - Temp < 40°C
- Systolic > 100 mmHg
Secondary (Soft Signs)
- Sweating
- Pale, moist, cool skin
- Cramping
- Nausea
- May or may not be present
The Athlete with Exertional Heat Injury: Severe (Heat Stroke) - Answers - Primary (Hard
Signs)
- Unconscious or decreased mental status (disoriented or irrational behaviour)
- Temp > 40°C
- Systolic < 100 mmHg
Secondary (Soft Signs)
- No sweat
- Hot, dry skin
- Weakness/flaccid
- Nausea
- May or may not be present
Management of Exertional Heat Injury: Mild Patients (Heat Exhaustion) - Answers - -
Alert with appropriate behaviour, near normal/ stable vital signs, and able to drink fluids
- Care on side-line for up to one hour with up to 2L of fluids
- Rest in the shade, cooling, rehydration, frequent vital signs and mental status
assessment (every 5-10 minutes)
- Upon realization that recovery will require more than this, or if the patient is not
improving, then evacuation to and ER should be quickly arranged
Management of Exertional Heat Injury: Severe Patients (Heat Stroke) - Answers - -
Mental status changes, amnesia, syncope, seizure, unable to drink fluids, unstable vital
signs, or temp > 40°C
- Cool first, transport second
- Care on sidelines includes aggressive cooling within golded first 30 minutes:
- Remove gear
- Ice/water submersion (best) or on core starting with armpits and groin/ fanning,
rehydration
- Frequent vital signs and mental status assessment (every 5-10 mins)
- Quickly arranging evacuation to an ER
- This is life threatening, these patients require immediate evaluation by an experienced
clinician and lab tests
Intrinsic Risk Factors for EHS - Answers - - Lack of acclimatization
