Matt Harmon

200 Chapter ten The aim of this thesis was to explore aspects of spontaneous and induced body temperature alterations in critically ill patients. The results from the studies presented in this thesis are discussed in the following paragraphs. Body temperature and sepsis Body temperature alterations are common in sepsis, but whether these temperature changes are beneficial or harmful to the host is controversial. The studies in this thesis on spontaneous hypothermia and induced normothermia in sepsis are seemingly at odds. On the one hand, spontaneous body temperature alterations in sepsis (i.e. fever and hypothermia), could both reflect beneficial adaptive responses at different stages of an infection. 1 Alternatively, actively cooling patients with fever and sepsis implies that fever is detrimental and should be treated. We do not fundamentally understand pathophysiologic mechanisms during sepsis and their relationship with body temperature. Therefore, the studies on sepsis and endotoxemia in this thesis were primarily aimed at understanding the pathophysiology underlying spontaneous and induced temperature alterations in sepsis in order to guide future temperature management strategies and ultimately optimize treatment for septic patients. Hypothermic sepsis. The survey presented in chapter two highlights how little we know about the optimal management of hypothermic sepsis. We found that definitions of spontaneous hypothermia and the practice of active rewarming in these patients are extremely variable. As a uniform definition of hypothermia will improve comparability of studies on hypothermia and probably would increase awareness, we call for a consensus definition of hypothermia. Among respondents there was also no consensus on the etiology of spontaneous hypothermia. The diverging opinions among physicians likely reflect a paucity on data on the hypothermic septic response and the difficulty in interpreting etiologic studies on hypothermic sepsis. Several studies have observed increased mortality in hypothermic septic patients. This mortality may be attributed to hypothermia, but the prognostic value of hypothermia could also simply reflect more severe sepsis. 2 Animal studies even suggest that hypothermia may be an adaptive response. 3 Determining the etiology of body temperature response is imperative, as this understanding could ultimately have treatment implications for patients . If hypothermic sepsis is indeed an adaptive response, this could imply that hypothermic patients should not be rewarmed to normothermia, which is often done in clinical practice. On the