Heat stroke

Generally associated with core temperatures >104°F (>40°C), though heat stroke can occur at lower core temperatures.

Diagnosis rests on the observation of hyperthermia in the presence of profound CNS dysfunction.

Medications may predispose patients to heat stroke (e.g., diuretics, antihypertensives).

Early cooling reduces mortality and morbidity, and should be initiated as soon as possible.

Evaporation and ice water immersion are both widely used as cooling methods.

Patients are at risk of multisystem organ failure, so careful monitoring is essential even after return to normothermia.

This topic covers the management of both heat stroke and heat exhaustion in adults

Heat stroke is defined as hyperthermia in the setting of CNS dysfunction. The core temperature with heat stroke is >104°F (>40°C), and typically ranges from 104°F to 111.2°F (40°C to 44°C), although higher core temperatures have been reported. Heat stroke can however occur at lower core temperatures. It should be suspected in the setting of high heat stress, through either exertion or environmental factors.

Heat exhaustion is a milder form of heat illness, where profound CNS disturbance is absent. In this case the core temperature is elevated (98.6°F to 104°F [37°C to 40°C]) but to a smaller extent than in heat stroke.