Pathophysiology and management of fever

Core body temperature is strictly regulated by autonomic and behavioural compensatory adaptations and an increase may represent a physiological stereotypical controlled response to septic and inflammatory conditions, or an uncontrolled drop in the hypothalamic thermoregulatory threshold. Fever has been demonstrated to be a potential mechanism of intrinsic resistance against infectious disease playing a pivotal role in the human evolution. High temperature may be detrimental during oxygen delivery-dependent conditions and in a neurological population. Despite this evidence, a definitive conclusion, between the association of fever and the outcome in critically-ill patients, is still lacking. The decision-making strategy in the context of fever management in critical care must be supported by single case assessment. This chapter summarizes the main physiological mechanisms of temperature control that physicians should consider when dealing with fever or deliberate hypothermia and analyses the main evidence in the role of fever in the critically ill in order to help bedside clinical strategy.