Heat stroke is a condition that is characterized by an elevated body temperature of 40ºC, that typically needs emergent treatment to prevent complications. It is most common in the summer months, and can be a consequence of either prolonged exposure to high temperatures (non-exertional) or prolonged physical exertion (exertional).
Non-exertional heat stroke is the classic type of heat stroke that we typically know about, and most often occurs in elderly patients with chronic diseases that may interfere with hydration, cooling, thermoregulation or prevent removal from a hot environment. Examples include prescription medications (beta-blockers, diuretics, etc.), recreational drugs (alcohol, cocaine), or medical conditions like cardiovascular disease, physical disability, and obesity among others. Exertional heat stroke typically occurs in younger and healthier individuals who undergo intense physical exercise in an environment with high temperature and humidity.
Heat stroke is characterized by a core body temperature of at least 40ºC, with typically CNS dysfunction that can manifest as delirium, convulsions or even coma. Other signs that are typically seen in patients are sinus tachycardia, tachypnea and hypotension. Other symptoms that may include flushed skin, headaches, nausea, and vomiting.
Neuroimaging
Reflects several pathophysiological dysfunctions
Associated brain injury
On neuroimaging, the most commonly reported findings are DWI abnormalities in the cerebellum; specifically, abnormal hyperintensity in the dentate nuclei, cerebellar hemispheres and cerebellar peduncles. DWI abnormalities in the cerebral cortex, hippocampus, thalami, basal ganglia and midbrain may also be found with later imaging commonly revealing diffuse cerebellar atrophy. These findings typically are bilateral and symmetrical but may occasionally present as asymmetrical and be in an atypical distribution. Other findings that may be seen in heat stroke include: ischemia, hemorrhage, signs of infarction, vasogenic edema, and cytotoxic edema, among others.
References
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