What are the parameters for permissive hypertension in ischemic stroke?

From the Guidelines

Permissive hypertension in ischemic stroke involves allowing blood pressure to remain elevated to maintain cerebral perfusion, with parameters generally set at below 220/120 mmHg for those not receiving thrombolytic therapy and below 180/105 mmHg for the first 24 hours after treatment for those receiving thrombolytic therapy. The management of blood pressure in acute ischemic stroke is crucial to prevent further brain damage and improve outcomes. According to the most recent guidelines 1, for patients with acute ischemic stroke who are not receiving thrombolytic therapy, blood pressure should generally be maintained below 220/120 mmHg. For those receiving thrombolytic therapy, blood pressure should be kept below 180/105 mmHg for the first 24 hours after treatment.

Key Considerations

• The goal is to maintain cerebral perfusion while avoiding excessive blood pressure reduction that could worsen cerebral ischemia.
• Blood pressure management should be individualized based on stroke severity, comorbidities, and whether reperfusion therapy was administered.
• Regular monitoring every 15 minutes during acute treatment is essential for appropriate titration of antihypertensive medications.
• First-line medications for blood pressure management include labetalol or nicardipine, with clevidipine as another option.

Parameters for Permissive Hypertension

• For patients not receiving thrombolytic therapy: below 220/120 mmHg.
• For patients receiving thrombolytic therapy: below 180/105 mmHg for the first 24 hours after treatment.
• Avoid rapid or excessive BP reduction as it may worsen cerebral ischemia by decreasing perfusion to the penumbra—the vulnerable tissue surrounding the infarct core.

Evidence-Based Recommendations

The recommendations are based on the latest guidelines from the European Heart Journal 1, which emphasize the importance of careful blood pressure management in acute ischemic stroke to improve patient outcomes. The guidelines highlight the need for individualized treatment approaches, considering factors such as stroke severity and the use of reperfusion therapy. Previous studies and guidelines, such as those from the American Heart Association 1 and the American Heart Association Stroke Council 1, also support these recommendations, emphasizing the importance of maintaining adequate cerebral perfusion pressure while avoiding excessive blood pressure reduction.

From the Research

Permissive Hypertension Parameters in Ischemic Stroke

The parameters for permissive hypertension in ischemic stroke are as follows:

• Systolic blood pressure greater than 220 mm Hg or diastolic blood pressure greater than 120 mm Hg, at which point medications should be considered 2, 3, 4
• For patients undergoing intravenous thrombolysis, blood pressure should be reduced and maintained below 185 mm Hg systolic for the first 24 hours 2, 3
• A reasonable goal for patients with marked elevation in blood pressure is to lower blood pressure by 15% during the first 24 hours after onset of stroke 2, 4

Blood Pressure Management

Blood pressure management in acute ischemic stroke is crucial, and the optimal approach remains a topic of debate:

• Elevated blood pressure is common in acute ischemic stroke and is related to mortality and disability, yet excessive blood pressure lowering can be detrimental 5
• Permissive hypertension is recommended during the first 24 hours after stroke onset, but there is ongoing uncertainty regarding the most appropriate blood pressure management in the acute phase of ischemic stroke 5, 3
• The use of predictable and titratable medications that judiciously reduce the initial presenting mean arterial pressure is recommended in situations where antihypertensive treatment is warranted 4

Clinical Considerations

Clinical considerations play a significant role in determining the optimal blood pressure management strategy:

• Comorbid conditions such as myocardial infarction, left ventricular failure, aortic dissection, preeclampsia, or eclampsia would override the guidelines for permissive hypertension, and a lower blood pressure would be preferred in these conditions 2
• Children with acute strokes should be managed in the same way as adults, with extrapolated lowering of blood pressures, until further evidence emerges 2
• The treatment choice should be adjusted to different clinical and blood pressure parameters, providing a better decision-making approach 5