The Impact of Mild Hypothermia on Vasospasms in Patients after Severe Subarachnoid Haemorrhage

Vasospasms occur in 30 % of patients after subarachnoid haemorrhage (SAH). The most severe spasms are in patients with Hunt and Hess IV and V, who have usually much blood in the basal cisterns. According to some reports, hypothermia could decrease the incidence and severity of vasospasms in these patients. We have analysed 15 patients (HH IV and V) after SAH from a ruptured intracranial aneurysm. In 8 patients the aneurysm was embolised during the first 4 days, 3 patients were operated on because of intraparenchymal haematoma and their aneurysm was clipped, the other 4 patients were initially treated conservatively. In all patients mild hypothermia (34 °C for 72 hours) had been started immediately after their admission by means of cooling blankets. Monitoring of ICP (intraventricular), CPP and jugular bulb oxymetry was instituted and everyday TCD examination was performed. Results – ICP, CPP and jugular bulb oxymetry were maintained in the normal range in all patients. In 11 patients, however, severe vasospasms with infarctions on the CT scan occurred (during days 5 and 16 after SAH). TCD showed increased velocities only in 6 of these patients. Ten patients with vasospasms died within 6 months after SAH. One patient remained vegetative, 1 severely disabled, and 3 had a good outcome (2 of them had intraparenchymal haematoma). Hypothermia applied immediately after SAH does not seem to decrease either the incidence or the severity of vasospasms in HH IV and V patients after SAH.