Temperature regulation as possible prognostic indicator in patients with acute intracranial lesions

Abstract

24 patients, 16 after severe head injury and 8 after spontaneous intracranial haematoma, were investigated by external cold load in order to determine their thermoregulatory capabilities. Tympanic temperature, several skin temperatures and oxygen consumption were measured. The patients where examined for SSEP and AEP. The cold induced thermoregulatory threshold temperature was determined by calculating the mean body temperature and by determining mean body temperature at which oxygen consumption increased due to the external cold load. In all patients core temperature and mean body temperature were significantly elevated by 1°C compared to controls. There was no difference of the course of the various body temperatures during cold load in the patient groups. In the trauma group 8 patients were able to increase oxygen use (V̇O2) during cold exposure, the other 8 patients showed no physiological thermoregulatory reaction. The heatproduction threshold temperature was increased by 1°C in the patient groups compared to controls. There was no significant correlation of AEP and SSEP findings to a preserved or disturbed thermoregulatory reaction. In the trauma patients, who were able to respond to a cold load, the outcome was significantly better (GOS = 3-5), than in those patients, who did not show a physiological increase of V̇O2 due to the cold load (GOS = 1-2). In conclusion, measurement of body temperatures alone is not sufficient to determine termoregulatory capacities. An examination using thermophysiological methods however provides more information about the function and structure damaged after severe head injury. An intact thermoregulatory systems seems to be correlated with a better prognosis after head injury.