Isao Nishihara

Ultra-Early Induction of Brain Hypothermia for Patients with Poor-Grade Subarachnoid Hemorrhage

The potential of hypothermia in reducing neuronal damage has been demonstrated in various neurological emergencies. However, its safety, feasibility, and potential benefits for poor-grade subarachnoid hemorrhage (SAH) are uncertain. We induced brain hypothermia in 35 patients (14 men and 21 women; mean age 58 ± 12 years; range 25–70 years) with SAH classified in Grade V by the World Federation of Neurosurgical Societies and evaluated the outcome. Hypothermia was induced by surface cooling immediately after diagnosis of SAH and was followed by urgent surgical obliteration of the ruptured aneurysm. The core temperature was maintained at 33°–34°C for at least 48 h; subsequently, patients were rewarmed 1°C per day. Median time from onset to arrival, cerebral angiography, and surgery was 31.5, 88.5, and 174.5 min, respectively. The core temperature (mean ± standard deviation) was 35.8° ± 1.0°C on arrival, 34.8° ± 1.0°C just before surgery, 34.0° ± 0.7°C at the beginning of microsurgery, and 33.7° ± 0.8°C immediately after surgery. Hypothermia was completed in all patients without serious complications over a period of 6–22 days, with a mean of 9.4 days. The Glasgow Outcome Scale assessed at 3 months after onset was as follows: 4 (11.4%), good recovery; 6 (17.1%), moderate disability; 17 (48.6%), severe disability; 4 ( 11.4%), vegetative state; 4(11.4%), death. Poor outcome was mostly related to primary brain damage; cerebral vasospasm occurred in four patients. Ultra-early induction of hypothermia is feasible and possibly beneficial in poor-grade SAH without increasing morbidity and mortality.