What is the recommended duration of permissive hypertension for acute Cerebral Vascular Accident (CVA)?

From the Guidelines

The recommended duration of permissive hypertension for acute CVA is typically 24-48 hours after symptom onset, during which blood pressure should generally not be treated unless it exceeds 220/120 mmHg, as stated in the 2024 ESC guidelines for the management of elevated blood pressure and hypertension 1.

Key Considerations

• The approach to blood pressure management differs for hemorrhagic strokes or patients who receive thrombolytic therapy (tPA), where blood pressure should be maintained below 180/105 mmHg immediately.
• The permissive hypertension strategy is based on the understanding that autoregulation of cerebral blood flow is impaired in the acute stroke setting, and the brain becomes dependent on systemic pressure to maintain adequate perfusion to vulnerable tissue.
• Abrupt lowering of blood pressure during this critical period could potentially expand the infarct size by reducing blood flow to the ischemic penumbra, the salvageable tissue surrounding the core infarct.

Management Guidelines

• 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.
• Patients with acute ischaemic 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.

Treatment Recommendations

• For patients with systolic BP ≥220 mmHg, careful acute BP lowering with i.v. therapy to <180 mmHg should be considered 1.
• In patients undergoing treatment with i.v. thrombolysis, BP should be lowered to <185/110 mmHg prior to thrombolysis and then maintained at <180/105 mmHg over the following 24 h 1.
• For stable patients who remain hypertensive (≥140/90 mmHg) ≥3 days after an acute ischaemic stroke, initiation or reintroduction of BP-lowering medication is recommended 1.

From the Research

Duration of Permissive Hypertension for Acute CVA

The recommended duration of permissive hypertension for acute Cerebral Vascular Accident (CVA) is not explicitly stated in the provided studies. However, the studies discuss the management of elevated blood pressure in patients with acute ischemic stroke or intracerebral hemorrhage.

Blood Pressure Management

• The studies suggest that antihypertensive agents such as labetalol, nicardipine, and hydralazine can be used to manage elevated blood pressure in patients with acute CVA 2, 3, 4.
• The optimal antihypertensive regimen for controlling blood pressure before alteplase therapy remains unclear 2.
• Nicardipine offers an alternative to labetalol with similar tolerability and appears to provide a smoother blood pressure control compared to labetalol 4.

Time to Blood Pressure Control

• The median time to blood pressure control was 10,22, and 15 minutes in the labetalol, nicardipine, and hydralazine groups, respectively 2.
• Patients who received labetalol had an average time to blood pressure control of 10 minutes longer in those who received 10 mg initially versus those who received 20 mg 2.
• The time to goal blood pressure was comparable between labetalol and nicardipine continuous infusions 3.

Prehospital Diagnosis of Acute CVA

• The accuracy of prehospital diagnosis of acute CVA is crucial for timely treatment 5, 6.
• Emergency physicians appear to be sensitive in diagnosing CVAs but their overall accuracy does not seem high 5.
• Ambulance physicians are highly sensitive in diagnosing any CVA, and are correct in 8 out of 10 cases 6.