Early temperature and mortality in critically ill patients with acute neurological diseases: trauma and stroke differ from infection

BACKGROUND: Fever suppression may be beneficial for patients with traumatic brain injury (TBI) and stroke, but for patients with meningitis or encephalitis [central nervous system (CNS) infection], the febrile response may be advantageous. OBJECTIVE: To evaluate the relationship between peak temperature in the first 24 h of intensive care unit (ICU) admission and all-cause hospital mortality for acute neurological diseases. DESIGN, SETTING AND PARTICIPANTS: Retrospective cohort design from 2005 to 2013, including 934,159 admissions to 148 ICUs in Australia and New Zealand (ANZ) and 908,775 admissions to 236 ICUs in the UK. RESULTS: There were 53,942 (5.8 %) patients in ANZ and 56,696 (6.2 %) patients in the UK with a diagnosis of TBI, stroke or CNS infection. For both the ANZ (P = 0.02) and UK (P < 0.0001) cohorts there was a significant interaction between early peak temperature and CNS infection, indicating that the nature of the relationship between in-hospital mortality and peak temperature differed between TBI/stroke and CNS infection. For patients with CNS infection, elevated peak temperature was not associated with an increased risk of death, relative to the risk at 37–37.4 °C (normothermia). For patients with stroke and TBI, peak temperature below 37 °C and above 39 °C was associated with an increased risk of death, compared to normothermia. CONCLUSIONS: The relationship between peak temperature in the first 24 h after ICU admission and in-hospital mortality differs for TBI/stroke compared to CNS infection. For CNS infection, increased temperature is not associated with increased risk of death. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00134-015-3676-6) contains supplementary material, which is available to authorized users.