Nicardipine vs. Labetalol

Acute ischemic stroke (AIS) is a leading cause of death and long-term disability worldwide. In patients who are candidates for intravenous thrombolysis and/or mechanical thrombectomy, rapid and controlled reduction of markedly elevated blood pressure (BP) before reperfusion therapy is critical for both treatment success and safety. International guidelines recommend intravenous nicardipine and labetalol as first-line antihypertensive agents in this setting; however, existing evidence comparing these two strategies is heterogeneous, and there is ongoing uncertainty regarding which agent facilitates faster and more stable BP control in the pre-reperfusion phase.

This prospective, randomized, single-blind, single-center clinical trial evaluates two commonly used intravenous antihypertensive regimens-nicardipine versus labetalol-for BP management in hypertensive AIS patients presenting to the emergency department. Consecutive adult patients with a clinical and radiological diagnosis of AIS and severely elevated BP at presentation who were planned for reperfusion therapy were screened for eligibility.

After written informed consent was obtained, eligible patients were randomly allocated in a 1:1 ratio to receive either intravenous nicardipine or intravenous labetalol. Randomization was performed using a computer-generated sequence with allocation concealment (sequentially numbered, opaque, sealed envelopes). Treating clinicians were aware of group allocation in order to administer the assigned drug, whereas outcome assessors and the statistical team remained blinded throughout data collection and analysis.

In the nicardipine arm, patients received a continuous intravenous infusion via a peripheral venous catheter using an electronic infusion pump, with the dose titrated at short intervals according to BP response. In the labetalol arm, patients received intermittent intravenous bolus doses through a peripheral line, with repeated boluses permitted up to a predefined cumulative limit when needed. In both groups, continuous cardiac and hemodynamic monitoring was maintained during antihypertensive therapy. BP was measured at frequent, standardized intervals using automated devices and verified manually when indicated. Once the predefined BP target recommended for pre-reperfusion management in AIS was achieved, the study drug was down-titrated or withheld, and patients proceeded to reperfusion therapy in accordance with current stroke guidelines and local protocols.

Time from initiation of antihypertensive treatment to achievement of target BP is the main efficacy endpoint of this trial. Secondary endpoints include additional time-based metrics related to reperfusion therapy, drug exposure parameters, the occurrence of predefined cardiovascular and hemodynamic adverse events during antihypertensive treatment, early neurological response, and in-hospital clinical course. Neurological status is assessed using the National Institutes of Health Stroke Scale (NIHSS) at baseline and during early follow-up, and standard radiological imaging is used to identify treatment-related intracranial complications. All clinically relevant data are collected prospectively using a standardized case report form and analyzed according to an intention-to-treat approach.

This study is designed to generate prospective randomized data on the comparative effectiveness and safety of nicardipine and labetalol for pre-reperfusion BP management in hyperacute AIS. By focusing on time-to-target BP and short-term clinical outcomes in a real-world emergency department setting, the trial aims to inform clinicians' choice between these two widely used antihypertensive strategies in time-critical stroke care.

Inclusion criteria

• Age ≥ 18 years
• Presentation to the emergency department with clinical and radiological evidence of acute ischemic stroke (cranial CT with or without CT angiography, or diffusion-weighted MRI)
• Initial systolic blood pressure (SBP) ≥ 185 mmHg and/or diastolic blood pressure (DBP) ≥ 110 mmHg

Exclusion criteria

• Age < 18 years
• Intracranial hemorrhage, subarachnoid hemorrhage, or other non-stroke structural pathology on initial neuroimaging
• Stroke mimics (e.g., hypoglycemia, postictal paresis)
• Absolute contraindication to reperfusion therapy at presentation such that pre-procedural blood pressure control is not planned as part of clinical management
• Achievement of target blood pressure with prior antihypertensive treatment or receipt of other intravenous antihypertensive agents before randomization
• Hemodynamic instability or respiratory failure requiring emergency intubation and advanced life support
• Contraindications to labetalol or nicardipine (e.g., severe bronchospastic disease, advanced atrioventricular block, or critical aortic stenosis)