GENERAL THERAPY
Blood pressure management in an acute stroke
Updated on 15/09/2024, published on 02/05/2023
- high blood pressure (BP) is a common correlate of an acute stroke
- except for hypertensive emergencies (hypertensive crisis) and hypertensive hemorrhage, high BP is usually a consequence rather than a cause of the acute neurological disorder
- the cause of increased blood pressure is multifactorial and may include:
- autoregulation trying to maintain adequate cerebral perfusion pressure (CPP)
- stress reaction triggered by pain and fear
- Cushing’s reaction (hypertension, bradycardia, and breathing disturbances) occurring in brainstem lesions or advanced intracranial hypertension with secondary brainstem compression
- autoregulation trying to maintain adequate cerebral perfusion pressure (CPP)
- rapid and significant BP lowering may be counterproductive and have a negative impact on the outcome by decreasing CPP
- except for hypertensive emergency, SAH, and ICH
- arterial blood pressure (BP) monitoring is a cornerstone of hemodynamic monitoring in neurocritical care
- both hypotension and hypertension can be detrimental to vital organ function and worsen the patient’s outcome
- BP monitoring techniques include:
- noninvasive BP monitoring (more common)
- intermittent (using inflatable cuff) – the proper cuff size is critical for accurate readings
- manual (auscultatory, palpatory)
- automated (oscillometric)
- continuous
- volume clamp method
- arterial applanation tonometry
- intermittent (using inflatable cuff) – the proper cuff size is critical for accurate readings
- invasive BP measurement via arterial cannulation (most commonly automated)
- noninvasive BP monitoring (more common)
- choice of BP monitoring method must be individualized
- low-risk patients – intermittent oscillometric BP monitoring
- high-risk, hemodynamically unstable patients – continuous BP monitoring (either noninvasive or invasive)
- critically ill patients/hypertensive emergencies – continuous invasive BP monitoring via an arterial catheter is preferred
Proper cuff size
- the cuff bladder length should be at least 80% of the upper arm circumference
- arm circumference < 35 cm – choose cuff size 16×30 cm (suitable for most patients)
- arm circumference 35-44 cm – cuff size 16×36 cm
- arm circumference > 45 cm – cuff size 16×42 cm
Acute ischemic stroke
- autoregulation is disrupted in the ischemic region (sometimes for weeks), and regional perfusion depends on systemic pressure (→ Regulation of cerebral perfusion)
- both excessively high and low blood pressure (U-curve) are negative prognostic factors in acute stroke patients
- there is a risk of hypoperfusion or, conversely, BBB damage and progression of edema or hemorrhagic transformation
- see the table for management in the first 24-48 hours (as recommended by AHA/ASA 2021 and ESO 2021)
- in general, higher blood pressure is beneficial
- consider all comorbidities and factors that may require more aggressive BP correction
- avoid excessive lowering when attempting to control BP prior to thrombolysis
- routine blood pressure lowering in the prehospital setting is generally not recommended (the INTERACT4 trial)
- prehospital treatment with glyceryl trinitrate should be avoided (potential harm in ICH patients)
- avoid sublingual nifedipine (may cause hypotension)
- in neurologically stable patients with BP >140/90 mm Hg, peroral (PO) therapy should be resumed within 48-72 hour
- it is unclear whether chronic PO therapy should be discontinued (ESO 2021)
- in patients with dysphagia, wait for improvement or place a nasogastric tube
Mechanical thrombectomy with or without IVT |
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Conservative therapy |
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according to AHA/ASA 2019 and ESO 2021
Intracerebral hemorrhage
- on admission, check BP every 5-10 minutes or start invasive BP monitoring
- aggressive and rapid treatment of hypertension is an essential therapeutic approach (along with correction of coagulopathy)
- high BP is associated with an increased risk of hematoma progression with worse clinical outcome
- initiating treatment within 2 hours of ICH onset and achieving the target within 1 hour may be useful to reduce the risk of hematoma expansion and improve functional outcome (AHA/ASA 2022, 2a/C-LD)
- ischemia around the hematoma plays a minor role (except perhaps in large hematomas), and BP reduction seems safe
- too extensive BP lowering is not beneficial (ATACH-2 trial)
- continue with chronic PO medications if possible; if dysphagia or decreased LOC is present, use parenteral therapy or place a nasogastric (NG) tube
- in patients with known hypertension, the target BP may be higher due to altered autoregulation with the risk of decreased CPP
- nitroprusside is not recommended due to its potential to increase intracranial pressure (ICP)
- smooth and sustained control of BP is required; avoid sudden drops or peaks in BP and maintain Mean Arterial Pressure (MAP) >85 mm Hg
- if the ICP is monitored, then correct BP to maintain CPP 60-80 mm Hg
Initial systolic blood pressure (SBP) 150-220 mm Hg in patients with ICH of mild-to-moderate severity |
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Initial SBP > 220 mmHg or large hematoma |
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Subarachnoid hemorrhage
- start noninvasive continuous BP monitoring immediately; in severe SAH or fluctuating BP, invasive monitoring is preferred
- BP control in SAH is complex; as there are reasons to both lower BP (to decrease the risk of rebleeding) and raise BP (to decrease the risk of delayed ischemic deficits)
- with an untreated source of bleeding, the aim is to maintain SBP ≤ 130-140 mm Hg
- 150-175 mm Hg postoperatively (⇒ ↑ CPP)
- 150-175 mm Hg postoperatively (⇒ ↑ CPP)
- in the presence of cerebral vasospasms and a secured aneurysm, the target SBP is ~ 180-220 mm Hg to improve cerebral perfusion
- excessive and rapid BP correction may be harmful (may lead to ↓CPP ⇒ risk of ischemia due to vasospasm)
- some surges of high blood pressure can be attenuated by adequate pain management or sedation
- antihypertensive therapy should only be started in patients with extreme elevations of blood pressure and rapidly progressive end-organ deterioration (new retinopathy, left-ventricular failure, nephropathy, etc.)
- preferably use labetalol, nimodipine, enalaprilat, esmolol, or urapidil
- avoid nitrates if possible, as they may increase intracranial pressure (ICP)