Significance of multimodal cerebral monitoring under moderate therapeutic hypothermia for severe head injury.

The therapeutic significance of moderate hypothermia and cerebral monitorings was assessed in the 10 patients with severe head injury. Cooling was begun as soon as possible after admission, using water blankets under general anesthesia. Jugular venous or tympanic temperature of patients was maintained at 32 degrees C for 3 to 5 days, then rewarming at the rate of 1 degree C a day was started. The intracranial pressure was controllable less than 20 mmHg under hypothermia. Moderate hypothermia reduced the jugular venous lactate (33.5%) as well as the cerebral blood flow velocity at M1 portion of middle cerebral artery (CBFV-M1) measured by transcranial Doppler (7.2%), while increase of the jugular venous oxygen saturation (SjO2) (17.9%) was observed in a majority of the patients. Our results demonstrated that moderate therapeutic hypothermia significantly reduced cerebral circulation and metabolism. Measurement of SjO2 and CBFV-M1 seems to be useful for estimation of cerebral circulation and metabolism in therapeutic hypothermia.