Heat Stroke


Signs and Symptoms of Heat Emergencies
Heat Cramps Heat Exhaustion Heat Stroke
Muscle cramps

Normal to mildly elevated temperature

Sweating

Symptoms seen in heat cramps plus:

Normal to elevated temperature [<40°C (<104°F)]

Nausea, vomiting, headache, malaise, dizziness

Orthostatic hypotension

Symptoms seen in heat exhaustion plus:

Elevated temperature [>40°C (>104°F)]

Neurologic abnormalities: inappropriate behavior, confusion, delirium, ataxia, coma, seizures

Anhidrosis or sweating

Two forms of heat stroke

Pathophysiology

Diagnostics

Diagnostic Testing

Differential Diagnosis

Acute Treatment

  1. ABCs, monitor, IVF, O2
  2. Lower body temperature to <100°F [37.8°C] within 1hr
  3. Remove from thermal heat stress, disrobe completely
  4. Begin cooling measures ASAP
  5. Stop cooling when body temp < 102.2° F [39°C]
  6. Exertional heat stroke
  7. Treat metabolic derangements aggressively

Further Treatment

  1. ICU care for complications of heat stroke

Disposition/Follow-Up

  1. Admit to hospital, consider ICU
  2. Prognosis varies with person's age and the circumstances of the heat stroke

Long-Term Care

Prevention


 

Complications Of Heat Stroke
  Early Late
Vital signs Hypotension
Hypothermic overshoot
Hyperthermic rebound
Muscular Rhabdomyolysis
Neurologic Delirium/coma
Seizure
Cerebral edema
Encephalopathy
Persistent neurologic deficit
Cardiac Heart failure Myocardial injury
Pulmonary Pulmonary edema Acute respiratory distress syndrome(ARDS)
Renal Oliguria Renal failure
GI Intestinal ischemia or infarction
Pancreatic injury
Hepatic dysfunction
Metabolic Hypokalemia
Hypernatremia
Hyponatremia
Hyperkalemia
Hypocalcemia
Hyperuricemia
Hematologic Thrombocytopenia
Disseminated intravascular coagulation

 

Summary Of Cooling Techniques
Cooling Method Advantages Disadvantages Recommendations
Evaporative methods Provides effective cooling Can cause shivering Strongly recommended
Readily available Less effective in humid environments
Practical Makes it difficult to maintain electrode positions
Well tolerated
Ice water immersion Provides effective cooling Can cause shivering Recommended
Poorly tolerated
Not compatible with resuscitation settings
Ice packs on neck, axillae, and groin Practical Has limited cooling efficacy Can be used as adjunct cooling method
Can be added to other cooling methods Poorly tolerated
Cardiopulmonary bypass Provides fast and effective cooling Invasive Recommended in severe or resistant cases when available
Not readily available
Setup is labor intensive
Cooling blankets Easy to apply Has limited cooling efficacy Not recommended when other methods available
Impedes use of other cooling methods
Cold water gastric, urinary bladder, rectal, or peritoneal lavage Invasive Not recommended
Labor intensive
May lead to water intoxication
Human experience is limited
Cold water IV infusion Carries unjustified complication rate Not recommended