GENERAL THERAPY

Blood pressure management in an acute stroke

Vloženo 25.10.2019, poslední aktualizace 02.05.2022

high blood pressure (BP) is a common correlate of an acute stroke
except for hypertensive emergency (hypertensive crisis) and hypertonic hemorrhage, high BP is a consequence and not a cause of the acute neurological disorder
the cause is multifactorial:
- autoregulation trying to provide sufficient CPP
- stress reaction to pain and fear
- Cushing’s reaction (hypertension, bradycardia, and breathing disturbances) in brainstem lesions or advanced intracranial hypertension with secondary brainstem compression
rapid and significant BP lowering (except for hypertensive emergency, SAH, and ICH) may be counterproductive, with a negative effect on outcome (due to a decrease of CPP)
preferred antihypertensive drugs in the acute phase: urapidil, labetalol, and enalapril

Blood pressure monitoring

arterial blood pressure (BP) monitoring is a mainstay of hemodynamic monitoring in neurocritical care
both hypotension and hypertension can impair vital organ function and worsen the outcome
BP monitoring techniques:
- non-invasive BP monitoring (more common)
  - intermittent (inflatable cuff) – the proper cuff size is critical
    - manual (auscultatory, palpatory)
    - automated (oscillometric)
  - continuous
    - volume clamp method
    - arterial applanation tonometry
- invasive BP measurement via arterial cannulation (most commonly automated)
choice of BP monitoring must be individualized
- low-risk patients – intermittent oscillometric BP monitoring
- high-risk, hemodynamically unstable patients – continuous BP monitoring (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 – cuff 16×30 cm (suitable for most patients)
- arm circumference 35-44 cm – cuff 16×36 cm
- arm circumference > 45 cm – cuff 16×42 cm

Acute ischemic stroke

2021 ESO guidelines on blood pressure management in acute ischemic stroke and intracerebral hemorrhage

autoregulation is disturbed in the ischemic region (sometimes for weeks), and regional perfusion depends on systemic pressure (regulation of cerebral perfusion)
too high or too low BP is a negative prognostic factor in acute stroke patients
- there is a risk of hypoperfusion or, conversely, HEB damage and progression of edema or hemorrhagic transformation
see the table for management in the first 24-48 h (as recommended by AHA/ASA 2021 and ESO 2021), especially considering all comorbidities and factors that will require more aggressive BP correction
routine blood pressure lowering in the prehospital setting is generally not recommended (ESO 2021
prehospital treatment with glyceryl trinitrate should be avoided (potential harm in ICH patients)
in neurologically stable patients with BP >140/90 mm Hg, resume PO therapy within 48-72 hours
- it is unclear whether chronic PO therapy should be discontinued (ESO 2021)
- in patients with dysphagia, wait for improvement or place NG tube

Mechanical thrombectomy with or without IVT

target BP after recanalization therapy depends on several factors, including the individual’s age, medical history, and the extent of the stroke
keep BP < 180/105 mmHg before and during IV thrombolysis/MT and then for the following 24 h → see thrombolytic protocols
- usual target SBP is around 140 mmHg
- the optimal BP target after mechanical recanalization remains an area of active research
reduction of SBP to ≤ 130 mmHg in the first 72h is not suggested
avoid periods of hypotension
induced hypertension is not recommended after successful MT (TICI 3) (ESO 2021)

Conservative therapy

patients with BP < 220/110 mmHg without comorbidities requiring BP correction – routine BP correction in the first 24 h is not suggested (ESO 2021) (AHA/ASA 2019 III/A)
patients with BP ≥ 220/110 mmHg without comorbidities requiring BP correction – the benefit of BP correction is unknown; a 15% reduction in the first 24h is reasonable and probably safe (ESO 2021 expert consensus) (AHA/ASA 2019 IIb/C-EO)
patients with neurological deterioration:
- routine use of vasopressors to increase BP and improve perfusion is not recommended
- if the deterioration is caused by the hypoperfusion (e.g., low intracranial flow on TCCD), it is suggested:
  - discontinue antihypertensive therapy
  - increase IV fluid intake
  - use non-pharmacological methods to increase blood pressure
  - finally, consider the use of vasopressors
treatment of BP in the acute phase is indicated in relevant comorbidities (hypertensive emergency) (AHA/ASA 2019 I/C-EO)
- pre-/eclampsia
- left-sided heart failure
- acute coronary syndrome (ACS)
- aortic dissection
- hypertensive encephalopathy
- concomitant SAH or cerebral aneurysm

according to AHA/ASA 2019 and ESO 2021

Intracerebral hemorrhage

2021 ESO guidelines on blood pressure management in acute ischemic stroke and 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
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 CBF decrease
nitroprusside is not recommended (the potential to increase ICP)
smooth and sustained control of BP is required; avoid sudden drops or peaks in BP and maintain MAP >85 mmHg
if the intracranial pressure (ICP) is monitored, then correct BP to maintain CPP 60-80 mmHg

Initial systolic blood pressure (SBP) 150-220 mm Hg in patients with ICH of mild-to-moderate severity

target SBP ≤ 140 mmHg (ESO guidelines 2021) (AHA/ASA 2022 2b/B-R)
- lowering SBP to 140mmHg is safe and may reduce hematoma expansion and lead to improved outcomes
- maintain in the range of 130-150 mm Hg
no significant clinical benefit of lowering < 140 mmHg has been demonstrated
- In the INTERACT2 trial, there were fewer patients with mRS 3-6 in the intensive treatment group (SBP<140 mmHg) compared to standard treatment group (SBP <180 mmHg); the difference was not statistically significant
- the benefit of lowering SBP <140 mmHg was not demonstrated in the ATACH -2 trial – lowering SBP <120 mm Hg may even be harmful
acute lowering of SBP to <130 mm Hg is potentially harmful (AHA/ASA 2022 3/B-R)
start antihypertensive treatment ASAP (ideally within 2h of symptom onset)
the decrease of SBP should not exceed 90 mmHg from baseline values (ESO guidelines 2021)
- greater BP reduction was significantly associated with acute kidney injury regardless of preexisting CKD (Burgess, 2018)

Initial SBP > 220 mmHg or large hematoma

limited data on the safety and efficacy of a target SBP ≤ 140 mmHg
SBP reduction should not exceed 90 mmHg from the baseline
cautious BP lowering is required in such patients ⇒ maintain CPP > 60–70 mmHg

Subarachnoid hemorrhage

start noninvasive continuous BP monitoring immediately; with severe SAH or fluctuating blood pressure, invasive monitoring is preferred
BP control in SAH is complex because there are rationales for both BP lowering (↓ rebleeding risk ) and raising (↓ risk of DID)
with an untreated source of bleeding, maintain SBP ≤ 130-140 mm Hg
- 150-175 mm Hg postoperatively (⇒ ↑ CPP)
in the presence of cerebral vasospasms in a patient with a secured aneurysm, the target SBP target is approx. 180-220 mmHg (to improve perfusion)
excessive and rapid BP correction may be harmful (↓CPP ⇒ risk of ischemia due to vasospasm)
avoid nitrates if possible (may increase ICP)