Heat stroke

Background

- often fatal, if survive probable brain damage

- usually v young or elderly, poor or socially isolated, no access to air conditioning

- heat stroke has microvasc thrombosis and endothelial cell damage- like DIC

Diagnosis

Heat Stroke- temp >40 and CNS dz

Heat Exhaustion- thirst, weakness, anxiety, dizzy, HA due to temp and water and salt depletion. Temp can be low, high or normal. (>37 but <40)

Signs & Symptoms

- heat stroke- hot and altered

- tachy and hyperventilation

- may have hypotn

- nonexertional heat stroke- have resp alk

- exertional- resp alk and lactic acidosis, also rhabdo and electrolyte abnormalities

- may have muscular rigidity

- hypoglycemia rare

- can progress to multiorgan faillure

Treatment

General

1) Rapid Cooling

• by conduction, evaporaton, convection
• continue only until the temperature drops to 38.5 or 39 C to avoid overshoot hypothermia
• evaporative cooling and iced gastric lavage recommended
  • e.g. luke-warm water or wet towels + blowing air with a fan
  • ay consider peritoneal and thoracic lavage
• cooling blankets may be effective for mild heatstroke
• immersing or covering the patient in ice NOT recommended (causes vasoconstriction and shivering)

• no drugs helpful (dantrolene not effective; antipyretics not studied)

Specific Co-Symptom

1. Shivering: Treat with chlorpromazine, benzodiazepines, or thiopental
2. Seizure: Treated with diazepam or thiopental (dilantin is ineffective)

Prognosis

- cns recovery is a favorable sign- but 20% will have resid damage

See Also

Environ: Heat Exhaustion

Source

Mistry, KajiQuestions, Donaldson