Abstract

This study aims to determine the effect of neurogenic, inflammatory, and infective fevers on acutely injured human spinal cord. In 86 patients with acute, severe traumatic spinal cord injuries (American spinal injury association Impairment Scale, grades A-C) we monitored (starting within 72 hours of injury, for up to a week) axillary temperature as well as injury site cord pressure, microdialysis, and oxygen. High fever (temperature >38 oC) was classified as neurogenic, infective, or inflammatory. The effect of these three fever types on injury site physiology, metabolism and inflammation was studied by analysing 2,864 hours of intraspinal pressure, 1,887 hours of microdialysis, and 840 hours of tissue oxygen data. High fever occurred in 76.7 % of the patients. The data show that temperature was higher in neurogenic than non-neurogenic fever. Neurogenic fever only occurred with injuries rostral to T4. Compared with normothermia, fever was associated with reduced tissue glucose (all fevers), increased tissue lactate to pyruvate ratio (all fevers), reduced tissue oxygen (neurogenic + infective fevers) and elevated levels of pro-inflammatory cytokines/chemokines (infective fever). Spinal cord metabolic derangement preceded the onset of infective but not neurogenic or inflammatory fever. By considering five clinical characteristics (level of injury, axillary temperature, leukocyte count, C-reactive protein, serum procalcitonin), it is possible to confidently distinguish neurogenic from non-neurogenic high fever in 59.3 % cases. We conclude that neurogenic, infective, and inflammatory fevers occur commonly after acute, severe, traumatic spinal cord injury and are detrimental to the injured spinal cord with infective fever the most injurious. Further studies are required to determine whether treating fever improves outcome. Accurately diagnosing neurogenic fever, as described, may reduce unnecessary septic screens and overuse of antibiotics in these patients.