title: Measuring brain temperature while maintaining brain normothermia in patients with severe traumatic brain injury.
abstract: The aim of this study was to evaluate the relationship between superficial temporal artery temperature (Tt), rectal temperature (Tr) and intracranial temperature (ICT) when attempting to keep the brain in a normothermic condition in patients with severe traumatic brain injury (TBI). We also compared the incidence of temperature gradient reversal in patients who survived (survivors) and patients who did not (non-survivors) and the difference in temperature gradient reversal between survivors and non-survivors. Tr is normally lower than and ICT and temperature gradient reversal, when Tr exceeds ICT, has been demonstrated to be an early sign of brain death. A total of 28 patients with severe TBI were enrolled retrospectively in our study between November 2008 and February 2010. Each patient's Tt, Tr and ICT was recorded every hour for 4 days. Our results show that the frequency of brain hyperthermia in our participants (ICT>38°C) was 17.7%. Using a paired t-test and Bland-Altman plots, it was shown that a significant temperature difference existed between Tt, Tr and ICT (p<0.001). The use of Spearman's correlation method revealed that Tt, Tr and ICT were positively correlated (p<0.001). Brain death occurred in five patients at a mean of 9.6 hours (range: 8-12 hours) after a temperature gradient reversal between Tt, Tr and ICT. Fisher's exact test showed that there was a significant difference in the incidence of temperature gradient reversal between Tt, Tr and ICT in survivors and non-survivors (p<0.001). We conclude that a significant temperature difference exists between Tt, Tr and ICT when maintaining brain normothermia. The daily practice of non-invasive Tt measurement may cause doctors to underestimate ICT; reversal of the ICT and Tt and/or Tr temperatures could be an early marker of a poor prognosis for patients with severe TBI.
authors: Institute of Clinical Medicine, School of Medicine, National Cheng-Kung University, Tainan, Taiwan.
authors: Jinn-Rung
authors: JR
authors: Kuo
authors: Chong-Jeh
authors: CJ
authors: Lo
authors: Che-Chuan
authors: CC
authors: Wang
authors: Chin-Li
authors: CL
authors: Lu
authors: Shu-Chin
authors: SC
authors: Lin
authors: Chiao-Fang
authors: CF
authors: Chen
mesh_terms: D000082:Acetaminophen / Q000494:pharmacology; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D018712:Analgesics, Non-Narcotic / Q000494:pharmacology; D001831:Body Temperature / Q000187:drug effects / Q000502:physiology*; D001921:Brain / Q000187:drug effects / Q000503:physiopathology*; D001929:Brain Edema / Q000209:etiology; D001930:Brain Injuries / Q000473:pathology* / Q000503:physiopathology* / Q000628:therapy; D005260:Female; D006801:Humans; D007427:Intracranial Pressure / Q000502:physiology; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D012189:Retrospective Studies; D013223:Statistics as Topic; D013699:Temporal Arteries / Q000503:physiopathology; D013997:Time Factors; D015599:Trauma Severity Indices; D055815:Young Adult
chemical_list: D018712:Analgesics, Non-Narcotic; D000082:Acetaminophen