[Clinical effect of nitroglycerin (GTN) on prevention of cerebral vasospasm]

Nitroglycerin (GTN) is widely used as a safe and effective dilator in patients with ischemic heart disease, and it is said that it dilates the cerebral vessels. So the authors are now using GTN for the prevention of cerebral vasospasm. 125 patients classified as Fisher's Group 2, 3 or 4 were operated on within 72 hours after subarachnoid hemorrhage due to ruptured cerebral aneurysm. 58 patients (GTN group) were treated with continuous intravenous infusions of GTN (0.5-1.0 micrograms/kg/min) for about 2 weeks after their operation, and another 67 patients (control group) were not administered GTN. The frequency of occurrence of symptomatic vasospasm decreased in each GTN group of Fisher's classification, and the severity of angiographic vasospasm also tended to decrease. Especially in patients with severe subarachnoid hemorrhage classified as CT group 3 or 4, symptomatic vasospasm occurred in 11 patients (30.6%) in the GTN group, but in 26 patients (63.4%) in the control group. Regarding the outcome, 10 patients (17.2%) in the GTN group showed poor results or died, as opposed to 22 patients (32.9%) in the control group. This difference was significant. Moreover the GTN group had no cases of mortality due to cerebral vasospasm. These results indicate that GTN can be effective for prevention of cerebral vasospasm and improve the prognosis in patients with serious subarachnoid hemorrhage due to a ruptured aneurysm.