Pyrexia in the critically ill

Temperature change is a conserved physiological response to infection. In animal studies cytokine responses associated with body temperature changes have been elucidated. In humans with sepsis, hypothermia appears to be associated with higher TNF-alpha concentrations and has a significantly higher mortality. However, the presence of pyrexia does not appear to influence outcome from infection. The routine use of antipyretic agents remains controversial and studies in patients with viral infections suggest that their use may be associated with an anti-inflammatory effect with prolonged time to viral clearance – and surprisingly, little evidence of improvement in symptoms. In one ICU study it would seem that ibuprofen when used in the sub-group of patients with hypothermia and sepsis is associated with an improvement in outcome.