What is the management of permissive hypertension following a cerebrovascular accident (CVA) or stroke?

From the Guidelines

Permissive hypertension is recommended in the acute phase after an ischemic stroke, generally allowing systolic blood pressure up to 220 mmHg and diastolic up to 120 mmHg for the first 24-48 hours unless thrombolytic therapy was administered. For patients who received thrombolytic therapy (such as tPA), blood pressure should be maintained below 180/105 mmHg 1. Antihypertensive medications should be withheld during this period unless blood pressure exceeds these thresholds or there are other compelling indications like aortic dissection or acute heart failure. If treatment is needed, intravenous labetalol (10-20 mg over 1-2 minutes, may repeat every 10 minutes up to 300 mg) or nicardipine (5 mg/hour IV, titrated by 2.5 mg/hour every 5-15 minutes, maximum 15 mg/hour) are preferred agents. This permissive hypertension approach maintains cerebral perfusion pressure in the affected area where autoregulation is impaired, helping to preserve the ischemic penumbra - tissue surrounding the infarct core that remains viable but at risk. Some key points to consider in the management of blood pressure after an ischemic stroke include:

• Avoiding rapid and steep reductions in blood pressure, as they may be harmful 1
• Withholding antihypertensive medications unless blood pressure exceeds the recommended thresholds or there are other compelling indications 1
• Using intravenous labetalol or nicardipine as preferred agents for blood pressure management 1
• Maintaining blood pressure below 180/105 mmHg in patients who received thrombolytic therapy 1
• Gradually reducing blood pressure to standard targets below 140/90 mmHg after 48-72 hours 1 Regular neurological assessments should be performed during blood pressure management to detect any deterioration that might indicate inadequate cerebral perfusion. The approach to arterial hypertension in acute ischemic stroke should prioritize maintaining cerebral perfusion pressure and avoiding overtreating patients with stroke until definitive data are available 1. In patients not receiving i.v. thrombolysis or mechanical thrombectomy, there is no evidence for actively lowering BP unless it is extremely high (e.g. >220/120 mmHg) 1. If BP is extremely high, an initial moderate relative reduction of 10%–15% over a period of hours may be considered 1. Therefore, patients with acute ischemic stroke and a BP of <180/105 mmHg in the first 72 h after stroke do not seem to benefit from the introduction or reintroduction of BP-lowering medication 1. For stable patients who remain hypertensive (≥140/90 mmHg) ≥3 days after an acute ischemic stroke, initiation or reintroduction of BP-lowering medication is recommended 1.

From the Research

Permissive Hypertension Post Stroke

• Permissive hypertension is a recommended approach in the early course of acute ischemic stroke, where antihypertensive treatment is withheld unless the systolic blood pressure is greater than 220 mm Hg or the diastolic blood pressure is greater than 120 mm Hg 2, 3.
• The goal of permissive hypertension is to avoid decreasing penumbral blood flow and exacerbating vasogenic edema, while also preventing the detrimental effects of high blood pressure on the neurologic outcome 2, 3.
• In patients undergoing intravenous thrombolysis for acute ischemic stroke, it is recommended that the blood pressure be reduced and maintained below 185 mm Hg systolic for the first 24 hours 2.
• 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.

Blood Pressure Management for Secondary Stroke Prevention

• Optimal blood pressure management is essential for the prevention of recurrent stroke, with a target blood pressure of <130/80 mmHg recommended by clinical practice guidelines 4.
• A stepped-care approach for cautious blood pressure lowering (usually to levels <140/90 mmHg) is preferred for patients with severe diseases of the major cerebral vessels, who have a high risk of recurrent ischemic stroke 4.
• More aggressive blood pressure lowering (to levels <120/80 mmHg) tends to benefit patients at high risk of intracranial hemorrhage 4.

Role of Ambulatory Blood Pressure Monitoring

• Twenty-four hour ambulatory blood pressure monitoring (ABPM) has become an important tool for improving the diagnosis and management of hypertension, and is increasingly used to assess patients with hypertension 5.
• ABPM has demonstrated chronic disruption of the circadian rhythm of blood pressure after acute phase of stroke and has shown higher sensitivity compared to office blood pressure in evaluating the effectiveness of antihypertensive treatment among stroke survivors 5.
• High 24-hour blood pressure is an independent predictor for cerebrovascular events, brain microbleeds, and subsequent development of dementia 5.