What is the target blood pressure (BP) range for managing hypertension in acute stroke infarct?

Blood Pressure Management in Acute Ischemic Stroke

For patients with acute ischemic stroke who are not receiving thrombolytic therapy, blood pressure should not be actively lowered unless it exceeds 220/120 mmHg, in which case it should be carefully reduced by approximately 15% during the first 24 hours after stroke onset. 1, 2

BP Management Based on Treatment Status

Patients Receiving Thrombolytic Therapy

• BP must be lowered to <185/110 mmHg before initiating intravenous thrombolysis 1
• After thrombolysis administration, maintain BP <180/105 mmHg for at least the first 24 hours 1, 3
• Labetalol is the preferred agent for BP control in this setting, with nicardipine as an alternative 1

Patients NOT Receiving Thrombolytic Therapy

• If BP <220/120 mmHg: No antihypertensive treatment is recommended during the first 48-72 hours 1, 2
• If BP ≥220/120 mmHg: Lower BP by approximately 15% during the first 24 hours 1, 4
• This permissive hypertension approach recognizes that cerebral autoregulation is impaired in acute stroke, making cerebral perfusion directly dependent on systemic blood pressure 2, 3

Rationale for Conservative BP Management

• In acute ischemic stroke, autoregulation in the ischemic penumbra is impaired 1, 2
• Both high and low systolic blood pressures have been associated with poor outcomes, with studies showing a U-shaped relationship between admission BP and clinical outcomes 1, 5
• Rapid or excessive BP reduction can compromise cerebral perfusion and worsen ischemic injury 2, 6
• Observational studies show that early aggressive BP lowering in patients without thrombolysis is associated with worse outcomes 3, 4

Timing of Antihypertensive Therapy Initiation

• For patients with BP <220/120 mmHg: Withhold antihypertensive medications for the first 48-72 hours 1, 2
• For stable patients who remain hypertensive (≥140/90 mmHg): Consider initiating or reintroducing BP-lowering medication ≥3 days after stroke onset 2, 7
• Starting or restarting antihypertensive therapy during hospitalization is reasonable in neurologically stable patients with BP >140/90 mmHg to improve long-term BP control 1

Recommended Medications When BP Lowering is Indicated

• Labetalol is preferred for BP control in acute ischemic stroke 1
• Nicardipine is an alternative, especially if the patient has bradycardia or congestive heart failure 1
• Nitroprusside can be used but may increase intracranial pressure 1
• Choose agents that avoid precipitous falls in blood pressure 2, 4

Common Pitfalls to Avoid

• Lowering BP too aggressively in the acute phase (avoid drops >15% in the first 24 hours) 2, 6
• Neglecting to restart antihypertensive medications after the acute phase in patients with pre-existing hypertension 2, 7
• Treating BP <220/120 mmHg in the first 48-72 hours in patients not receiving thrombolysis, which has been shown to be ineffective for preventing death or dependency 1
• Excessive BP reduction (>70 mmHg drop) which may cause acute renal injury and neurological deterioration 2, 8