Clinical Effects of Nimodipine in Prevention of Vasospasm After Subarachnoid Hemorrhage

A retrospective study was undertaken including all patients with a bleeding aneurysm consecutively admitted to our Department within 72 hours from SAH, with Hunt and Hess grades Ito IV. The control group consisted of 230 patients admitted from January 1981 to December 1985, and the study group consisted of 196 patients admitted from January 1986 to August 1990, all receiving i.v. nimodipine for the first 14 days of SAH (2 mg/h). Admission clinical grade was very similar in the opposite groups. A consistent or thick subarachnoid hemorrhage was more commonly observed in the study group (84% vs. 71%). Early surgery was adopted in 57% of cases in the study and 61% of cases in the control group. Clinical outcome was significantly better in the nimodipine group, with complete recovery in 71% of patients and a mortality rate of 13% (p=0.008 for complete recovery and p=0.0005 for mortality); considering only patients submitted to early surgery, there was still a significant difference for complete recovery (p = 0.02) and mortality (p=0.004) in favour of the nimodipine group. As a whole: a) permanent ischemic disturbances (not associated with other causes of deterioration) were significantly less common in the study than in the control group (4% vs. 13%, p = 0.001); b) CT infarction was observed in 9% of nimodipine and 19% of control patients (p = 0.005); c) vessel narrowing was observed with the same incidence in the opposite groups (50% in the nimodipine and 52% in the control group). It is concluded that i.v. nimodipine infusion significantly improves the outcome after SAH, and decreases the incidence of ischemic disturbances and CT infarction, although it does not decrease the occurrence of angiographical vessel narrowing; these effects are likely due to vasodilatation of the peripheral resistance vessels and/or to a cerebral metabolic effect.