Which Protocol for Milrinone to Treat Cerebral Vasospasm Associated With Subarachnoid Hemorrhage?

Abstract

Milrinone has emerged as an option to treat delayed cerebral ischemia after subarachnoid hemorrhage. However, substantial variation exists in the administration of this drug. We retrospectively assessed the effectiveness of 2 protocols in patients with angiographically proven cerebral vasospasm. During 2 successive periods, milrinone was administered using either a combination of intra-arterial milrinone infusion followed by intravenous administration until day 14 after initial bleeding (IA+IV protocol), or a continuous intravenous milrinone infusion for at least 7 days (IV protocol). The primary endpoint was the reversion rate of vasospastic arterial segments following the first IA infusion of milrinone (IA+IV protocol) compared with the reversion rate during the first week of IV infusion (IV protocol). There were 24 and 77 consecutive patients in IA+IV and IV protocols, respectively. The reversion rate was comparable between the 2 protocols: 71% (95% confidence interval [CI], 59%-83%) in the IA+IV protocol versus 64% (95% CI, 58%-71%) in the IV protocol (P=0.36). Rescue procedures for persistence or recurrence of vasospasm, that is, mechanical angioplasty and/or IA milrinone infusion, were similar between the 2 protocols. Patients with a good neurological outcome at 1 year, that is, modified Rankin Scale scores 0-2, were comparable between the 2 protocols. Side effects of milrinone were uncommon and equally distributed within the 2 protocols. These findings indicate that a continuous IV infusion of milrinone was as efficient as combined IA+IV infusion and suggest that this modality could be considered as a first easy-to-use option to treat patients with CVS.