Hyperthermia leads to direct cytotoxicity and tissue inflammation. It can progress to multiorgan failure.
Direct cytotoxicity
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Cellular complications may include deleterious changes affecting cell membranes, organelles, proteins and DNA. Electrolyte dysregulation may occur.
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Direct cell death can occur when temperatures near 41oC, in-keeping with protein denaturation.
Inflammatory response
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In hyperthermia, there is an early co-ordinated stress response involving heat shock proteins, proinflammatory cytokines and anti-inflammatory cytokines.
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A prolonged stress response leads to dysregulation of the inflammatory reaction, causing end-organ damage.
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Proposed mechanisms for injury are ischaemia, vasodilatation, oedema, vascular damage and coagulopathy.
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Systemically, there may be bacterial translocation through a dysfunctional gastrointestinal tract and endotoxaemia.
