[Intra-arterial administration of fasudil hydrochloride: duration of action]

Intra-arterial infusion (IA) of fasudil hydrochloride for cerebral vasospasm is performed in many institutions and is associated with few side effects. Nonetheless, as optimum dose and duration of action remain unknown, the present study aimed to clarify these variables. We performed intra-arterial injection of fasudil hydrochloride for eight patients with cerebral vasospasm 7-13 days after subarachnoid hemorrhage. Fasudil hydrochloride was administered via the internal carotid artery without selective microcatheterization, at a concentration and speed of 30 mg/20 ml/10-15 min, using a total dose of 30-60 mg. Cerebral angiography was used to measure change in blood vessel diameter at 19 points, and perfusion CT was used to detect changes in cerebral blood perfusion (CBP), cerebral blood volume (CBV), and mean transit time (MTT) at 12 hemispheres. Investigations were performed before IA, immediately after IA (post IA), and 4.5 to 6 hours later. For central vessels, (A1, M1) mean change in diameter (cm) measured pre IA, post IA, and 4.5-6 hours later was 1.2 +/- 0.68, 1.5 +/- 0.72, and 1.2 +/- 0.7, respectively. For peripheral vessels (peripheral to A1, M1, and the ophthalmic artery) change in diameter (cm) was 0.65 +/- 0.16, 0.97 +/- 0.24, and 0.71 +/- 0.24, respectively. Average CBP (m/100g/min) in the infused hemisphere at pre IA, post IA, and 4.5-6 hours later was 41.6 +/- 3.56, 46.4 +/- 5.82, 41.6 +/- 7.42, respectively. Average CBV (ml/100g) was 2.72 +/- 0.21, 2.73 +/- 0.21, 2.91 +/- 0.42, respectively and average MTT (sec) was 5.16 +/- 0.38, 4.57 +/- 0.70, 5.55 +/- 1.0, respectively. Changes in peripheral vessel diameter and in MTT were statistically significant. Therefore, when performing intra-arterial administration of fasudil hydrochloride, clinicians should be aware that vasodilator effect is less than 6 hours.