The Use of Mild Hypothermia in the Prevention of Secondary Brain Injury

Abstract

According to our hypothesis, only a subgroup of patients with a lesser extent of primary brain damage after severe head injury (particularly those with extracerebral hematomas) may benefit from therapeutic hypothermia. We have prospectively analyzed 72 patients with severe head injury who were randomized into a group with (n = 37) and without (n = 35) 34°C hypothermia maintained for 72h. The influence of hypothermia on intracranial pressure (ICP), cerebral perfusion pressure (CPP), and neurological outcome was analyzed in the context of the extent of the primary brain damage. Mean values recorded in the patients were as follows. Patients with normothermia and primary lesions (n = 17): Glasgow Coma Scale (GCS) on admission 4.59, ICP 18.88, CPP 73.71, Glasgow Outcome Scale (GOS) 3.47. Patients with normothermia and extracerebral hematomas (n = 20): GCS 4.0, ICP 16.6, CPP 70.85, GOS 2.9. Patients with hypothermia and primary lesions (n = 21): GCS 4.62, ICP 10.81, CPP 78.1, GOS 3.71. Patients with hypothermia and extracerebral hematomas (n = 14): GCS 4.5, ICP 13.21, CPP 78.43, GOS 4.64. Hypothermia was able to decrease ICP and increase CPP in both groups of patients regardless of the type of brain injury. Hypothermia was not able to improve outcome in patients with primary brain lesions; however, it was able to significantly improve outcome in patients with extracerebral hematomas who were threatened mostly by secondary ischemic brain damage.