Can nicardipine (calcium channel blocker) be given if suspecting a stroke?

Nicardipine Use in Suspected Stroke

Nicardipine can be used in suspected stroke, but with caution and specific guidelines depending on stroke type (ischemic vs. hemorrhagic) and blood pressure parameters. 1

Ischemic Stroke Guidelines

• For acute ischemic stroke with BP >220/120 mmHg, nicardipine is recommended as a second-line agent after labetalol, with a target mean arterial pressure (MAP) reduction of 15% within 1 hour 1
• For patients eligible for thrombolytic therapy with BP >185/110 mmHg, nicardipine can be used to achieve BP control before administering rtPA 1
• Initial nicardipine dosing should be 5 mg/h IV, titrated up by 2.5 mg/h every 5-15 minutes to a maximum of 15 mg/h 1
• Blood pressure should be monitored every 15 minutes for 2 hours from the start of treatment, then every 30 minutes for 6 hours, and then every hour for 16 hours 1

Hemorrhagic Stroke Guidelines

• For acute hemorrhagic stroke with systolic BP >180 mmHg, nicardipine is recommended as a second-line agent after labetalol 1
• In ICH patients with SBP between 150-220 mmHg, acute lowering of SBP to 140 mmHg is safe and can improve functional outcomes 1
• A clinical cohort study showed that patients receiving nicardipine-based BP lowering to reach an SBP target of <160 mmHg within 3 hours of ICH onset had better outcomes with the lowest achieved SBP (<135 mmHg) 1

Warnings and Precautions

• The FDA label specifically warns to "avoid systemic hypotension when administering nicardipine to patients who have sustained an acute cerebral infarction or hemorrhage" 2
• Blood pressure lowering should be accomplished gradually in a controlled manner compatible with the patient's clinical status 2
• Excessive blood pressure reduction (>50% decrease in MAP) has been associated with ischemic stroke and death 3
• Patients are often volume depleted due to pressure natriuresis; intravenous saline may be needed to correct precipitous blood pressure falls 3

Comparative Efficacy

• A prospective study comparing nicardipine to labetalol found that all patients who received nicardipine achieved goal BP compared to only 61% in the labetalol group 4
• Nicardipine demonstrated better maintenance of BP, greater percentage of time spent within goal, and significantly less BP variability compared to labetalol 4
• However, a larger retrospective study of 3,093 patients found no significant difference in percent time at goal BP between nicardipine (82%) and labetalol (85%) groups 5

Practical Administration

• For patients eligible for thrombolytic therapy, BP must be controlled to <185/110 mmHg before administering rtPA 1
• During and after thrombolytic therapy, BP should be maintained at or below 180/105 mmHg 1
• Administer through large peripheral veins or central veins rather than small peripheral veins to reduce the possibility of venous thrombosis and phlebitis 2
• Consider changing the site of drug infusion every 12 hours to minimize the risk of peripheral venous irritation 2

In conclusion, while nicardipine is an effective option for blood pressure management in stroke, it should be used with careful monitoring and appropriate dose titration to avoid excessive blood pressure reduction that could worsen cerebral perfusion in the setting of acute stroke.