| Heat stroke | Heat exhaustion |
Core body temperature | >40 to 40.5°C (104 to 105°F)Δ | ≤40°C (104°F) |
Mental status | Abnormal mental status (eg, obtunded, coma, delirium, hallucinations, seizures, ataxia, slurred speech) | Normal mental status, dizziness, or mild confusion that rapidly normalizes within 30 minutes of treatment. May see syncope with rapid recovery of alertness. |
Airway and breathing | May be compromised due to altered mental status, tachypneic | Clear airway, may be tachypneic |
Circulation | Tachycardia with hypotension, moderate to severe dehydration | Tachycardia with normal blood pressure, mild to moderate dehydration |
Skin findings | Dry skin (classic heat stroke) or sweating (exertional heat stroke) | Sweating |
Other clinical features | - Vomiting
- Diarrhea
- Clinical and laboratory findings of DIC, rhabdomyolysis, acute renal failure, cardiogenic shock, and liver failure
| - Nausea, vomiting
- Headache
- Fatigue, weakness
- In some patients, hyponatremia or hypernatremia
|