-Higher ratio of body surface area to body mass
-Fewer sweat glands, and there for less sweat production
-Greater heat production
Heat related illness occur more frequently when both temperature and humidity are high, when humidity reaches 75% surrounding air so saturated that sweat can no longer evaporate and body loses one of its mechanisms of heat loss. Last year 3 high school football players died as a result of heat stroke.
Heat related illness spans a continuum from heat cramps through heat exhaustion and heatstroke (which may be fatal).
Heat Cramps brief sever muscle contractions usually legs, shoulder and abs. usually last less than a minute, feel hard mass along affected muscle. May happen during or after exercise. Cramps themselves are not serious but need to realize that they may indicate impending heat exhaustion. Supportive treatment. Move to shade, provide cold fluids and salty foods (do not give salt tablets gastric irritant and may cause vomiting which makes you worse)
Two types of heat exhaustion: Water depletion (more common) and salt depletion.
If you are working or exercising in heat and don’t stop to take in adequate fluid will lead to water depletion and heat exhaustion.
Symptoms may be vague: nausea, vomiting, headache and mild temperature elevation. Mental status usually normal but some may complain of weakness, dizziness or fainting.
Need supportive therapy and recognize early. Move to shade, push fluids and may need IV support if they are vomiting. Don’t ignore symptoms and have progression to heat stroke
Exertion heatstroke may occur in young athletes often at the start of the sport season, before they are adequately conditioned and acclimated. Have elevated core body temperature, and central nervous system impairment. If there is a life-threatening emergency, treat vigorously to lower the core body temperature. Untreated may lead to multisystem organ failure and death. Head to the ER immediately and try to cool with the patient with ice packs and spray with water.
The AAP has recommendations for children and adolescents who exercise in hot weather:
-Reduce intensity of activities that last for more than 15 minutes when temp and humidity are high.
-At the beginning of strenuous exercise program or traveling to hotter environment, allow child to acclimatized, ideally over 10 -14 days and comprise 8 – 10 exposures lasting 30 – 45 minutes each day.
-Be well hydrated prior to participating and periodic drinking during activity.
For every 20 min of exercise a child weighing 80 lbs should drink 5 ounces of fluid and 120 lb should drink 9 oz of fluid. For events lasting over 1 hour need fluids with electrolytes and glucose, not just water.