Spontaneous Body Temperature Fluctuations in Neurological Patients

Although body temperature is one of the most tightly regulated homeostatic parameters in humans, temperature abnormalities are frequently encountered in the in-hospital patient population, particularly in those with central nervous system (CNS) pathologies. CNS injuries are a prevalent cause of death and disability in young persons and on the rise among older persons. Brain and body temperature fluctuations in patients with cerebral pathologies are as of yet poorly characterized. The objective of this paper was to review our state of knowledge about spontaneous temperature fluctuations, specifically as they pertain to neurological patients. We provide an overview of the data on spontaneous temperature fluctuations (hyperthermia and hypothermia). ‘Is Hotter Better?' evaluates how ambient temperature impacts human thermoregulation and health, reviews therapeutic benefits of induced hyperthermia, and discusses adverse outcomes of spontaneous hypothermia. In ‘Is Colder Cooler?,' we review the link between fever and poor outcomes, the detrimental effects of spontaneous hypothermia on mortality, beneficial cerebral effects of spontaneous hypothermia after ischemic brain insult, and the clinical role of therapeutic hypothermia. We conclude that the net effects of early and spontaneous body temperature fluctuations in illness likely depend on the underlying pathological process, specific tissue vulnerabilities towards temperature-induced collateral damage, and the magnitude and duration of spontaneous temperature fluctuations. The paper calls for the community to expand our attention to investigating effects of the entire range of spontaneous body temperature fluctuations in CNS illness, because at present, the therapeutic effect of targeted temperature management in neurological patients remains uncertain.