Temperature disturbances in traumatic brain injury: relationship to secondary insults, barbiturate treatment and outcome.
OBJECTIVES
To describe the occurrence of spontaneous hyper- and hypothermia in patients with traumatic brain injury using a computerized data collecting system, to show how temperature correlates with other secondary insults, to describe how temperature affects outcome and to show how barbiturate treatment influences those analyses.


METHODS
Patients with > or = 54 hours of valid monitoring within the first 120 hours after trauma (one value/min) for temperature, intracranial pressure, cerebral perfusion pressure, systolic blood pressure, mean blood pressure and heart rate were included. Correlation analyses were performed between temperature and other secondary insult variables. The non-linear relationship between temperature and outcome (measured by Glasgow outcome scale 6 months post-trauma) was illustrated using a neural network.


RESULTS
Of the 53 patients, 44 experienced hyperthermia (>38 degrees C) and 29 experienced hypothermia (<36 degrees C). Hyperthermia correlated with occurrence of high blood pressure and high CPP. In individuals, hyperthermia also correlated with ICP and tachycardia. There was a trend towards better outcome for patients with normal temperature than those with hyper- or hypothermia (favorable outcome 64% versus 29 and 33% respectively). When patients treated with barbiturates were excluded, 60% showed favorable outcome in the hypothermia group as well. Barbiturate treatment also confounded analyses regarding temperature and other secondary insults.


DISCUSSION
Patients with hyperthermia, hypertension, high CPP and tachycardia may suffer from a hyperdynamic state. This may worsen outcome and hence clinical awareness is important. Barbiturate treatment confounds several analyses which have not been shown before. We recommend those patients to be analysed separately in future studies.