Brain temperature but not core temperature increases during spreading depolarizations in patients with spontaneous intracerebral hemorrhage.

Spreading depolarizations (SDs) are highly active metabolic events, commonly occur in patients with intracerebral hemorrhage (ICH) and may be triggered by fever. We investigated the dynamics of brain-temperature (T-brain) and core-temperature (T-core) relative to the occurrence of SDs. Twenty consecutive comatose ICH patients with multimodal electrocorticograpy (ECoG) and T-brain monitoring of the perihematomal area were prospectively enrolled. Clusters of SDs were defined as >= 2 SDs/h. Generalized estimating equations were used for statistical calculations. Data are presented as median and interquartile range. During 3097 h (173 h [81-223]/patient) of ECoG monitoring, 342 SDs were analyzed of which 51 (15%) occurred in clusters. Baseline T-core and T-brain was 37.3 degrees C (36.9-37.8) and 37.4 degrees C (36.7-37.9), respectively. T-brain but not T-core significantly increased 25 min preceding the onset of SDs by 0.2 degrees C (0.1-0.2; p < 0.001) and returned to baseline 35 min following SDs. During clusters, T-brain increased to a higher level (+0.4 degrees C [0.1-0.4]; p = 0.006) when compared to single SDs. A higher probability (OR = 36.9; CI = 36.8-37.1; p< 0.001) of developing SDs was observed during episodes of T-brain >= 38.0 degrees C (23% probability), than during T-brain <= 36.6 degrees C (9% probability). Spreading depolarizations - and in particular clusters of SDs - may increase brain temperature following ICH.