Abstract T P233: Intravenous Nicardipine Dosage for Blood Pressure Lowering in Acute Intracerebral Hemorrhage: The SAMURAI-ICH Study

Purpose: Intravenous nicardipine is commonly used to reduce elevated blood pressure (BP) in acute intracerebral hemorrhage (ICH). We determined factors associated with nicardipine dose and the association of the dose with clinical outcomes in hyperacute ICH. Methods: Hyperacute ( 180 mmHg were registered in a multicenter observational study (the SAMURAI-ICH study). All patients initially received 5mg/h of intravenous nicardipine to lower BP. The dose was adjusted to maintain SBP between 120 and 160 mmHg based on BPs measured every 15 min during the initial 2 h and every 60 min in the following 22 h. Maximum hourly and total doses during the initial 24 h were calculated. Associations of the doses with neurological deterioration (a decrease of ≥2 in GCS or an increase of ≥4 in NIHSS score at 72 h after treatment initiation), hematoma expansion (>33% from baseline to 24 h), and unfavorable outcome (modified Rankin Scale score 4-6 at 3 months) were assessed. Results: Of 211 patients in the registry, 206 patients (81 women, 65.8±11.8 years old) whose nicardipine data were available throughout 24-h observation were studied. Initial BP was 201.9±15.9/107.9±15.1 mmHg. Median time to reach target SBP range was 30 min (IQR 15-45). Maximum and total doses were 9.1±4.2mg/h and 123.7±100.2mg/day, respectively. Multivariate analyses revealed that male sex [standardized regression coefficient (β)=0.20, p=0.0030 for maximum dose; β=0.25, p=0.0002 for total dose], age (β= -0.28, p=0.0002; β= -0.25, p=0.0005) and initial SBP (β=0.19, p=0.0018; β=0.18, p=0.0021) were independently associated with both maximum and total doses. Body weight (β=0.20, p=0.0084) was independently associated with total dose. After multivariate adjustment, maximum dose (per 1mg/h; OR 1.25, 95% CI 1.09-1.45; p=0.0022) was independently and total dose (per 10mg/day; OR 1.06, 95% CI 0.998-1.132; p=0.0555) tended to be associated with neurological deterioration. Nicardipine dose was not associated with hematoma expansion and unfavorable outcome. Conclusions: Nicardipine dosage is roughly predictable with sex, age, body weight and initial SBP in acute ICH. Maximum hourly nicardipine dose was associated with neurological deterioration.