Signs and Symptoms


Exercise-Associated Muscle Cramps:  Cramps that present as painful, involuntary muscle contraction both during and/or after intense exercise.

  • Dehydration
  • Thirst
  • Sweating
  • Transient Muscle Cramps
  • Fatigue

Heat Syncope:  Dizziness resulting from exposure to high temperatures.

  • Dehydration
  • Fatigue
  • Tunnel Vision
  • Pale or Sweaty Skin
  • Decreased Pulse Rate
  • Dizziness
  • Lightheaded
  • Fainting

Exercise (Heat) Exhaustion:  Inability to continue physical exertion in combination with heavy sweating, and/or dehydration, and/or sodium loss, and/or energy depletion.  Although it may appear to be heatstroke, the core temperature is <104°F.

  • Normal or Elevated Body-Core Temperature
  • Dehydration
  • Dizziness
  • Lightheaded
  • Syncope (drop in blood pressure leading to temporary unconsciousness)
  • Headache
  • Nausea
  • Anorexia (loss of appetite)
  • Diarrhea
  • Decreased Urine Output
  • Persistent Muscle Cramps
  • Pallor (pale appearance)
  • Profuse Sweating
  • Chills
  • Cool and Clammy Skin
  • Intestinal Cramps
  • Urge to Defecate
  • Weakness
  • Hyperventilation

Exertional Heatstroke:  Elevated core temperature ≥104°F associated with signs of organs system failure as a result of hyperthermia.

  • High Body-Core Temperature 104°F
  • Central Nervous System Changes
    • Dizziness
    • Drowsiness
    • Irrational Behavior
    • Confusion
    • Irritability
    • Emotional Instability
    • Hysteria
    • Apathy
    • Aggressiveness
    • Delirium
    • Disorientation
    • Staggering
    • Seizures
    • Loss of Consciousness
    • Coma
  • Dehydration
  • Weakness
  • Hot and Wet or Dry Skin
  • Tachycardia (abnormal heat beat of 100 to 120 beats/minute)
  • Hypotension (low blood pressure)
  • Hyperventilation
  • Vomiting
  • Diarrhea

Exertional Hyponatremia:  Unsafe drop in normal sodium levels typically brought on by protracted physical exertion of water intoxication.

  • Body-Core Temperature <104°F
  • Nausea
  • Vomiting
  • Extremity (hands and feet) swelling
  • Low Blood-Sodium Level
  • Progressive Headache
  • Confusion
  • Significant Mental Compromise
  • Lethargy
  • Altered Consciousness
  • Apathy
  • Pulmonary Edema (build-up of  fluid in the lungs that makes it difficult to breathe)
  • Cerebral Edema (swelling of the brain caused by the build-up of fluid)
  • Seizures
  • Coma

(Source:  NATA)


Evaluation

The evaluation algorithm shown below is an adaptation of the one found on the AFP website.  It is a simple methodology to help you properly diagnose and appropriately treat a suspected heat-related illness.

Initial Evaluation Algorithm

 

Next: Treatment