The influence of mild hypothermia on ICP, CPP and outcome in patients with primary and secondary brain injury

Aim of this study was to examine the hypothesis that only a subgroup of patients with lesser primary brain damage after severe head injury may benefit from therapeutic hypothermia. We prospectively analysed 72 patients with severe head injury, randomized into groups with (n = 37) and without (n = 35) hypothermia of 34 degrees C maintained for 72 hours. The influence of hypothermia on ICP, CPP and neurological outcome was analysed in the context of the extent of primary brain damage. Patients with normothermia and primary lesions (n = 17) values: GCS on admission 5 (median), ICP 18.9 (mean), CPP 73 (mean), GOS 4 (median). Patients with normothermia and extracerebral hematomas (n = 20): GCS 4, ICP 16, CPP 71, GOS 3. Patients with hypothermia and primary lesions (n = 21): GCS 4,62, ICP 10, 81, CPP 78,1, GOS 4. Patients with hypothermia and extracerebral hematomas (n = 14): GCS 5, ICP 13.2, CPP 78, GOS 5. Hypothermia decreased ICP and increased CPP regardless of the type of brain injury. Hypothermia was not able to improve outcome in patients with primary brain lesions but this pilot study suggests that it significantly improves outcome in patients with extracerebral hematomas.