Blood Pressure Target in Intracranial Hemorrhage

Author: Maha Salama, PGY-3

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Background:

• Goals of blood pressure management in patients with ICH. Systolic BP target is routinely <160 mmHg with fear of acute ischemic stroke in patients where BP is lowered “too much too fast.”
• A multicenter observational study of acute ICH found acute cerebral ischemia to be an independent predictor of poor functional outcomes at 3 months.
• INTERACT-2 led to protocol change from goal SBP <160 mmHg to <140 mmHg.

Article Reviewed:

• Buletko AB, Thacker T, Cho SM, et al. Cerebral Ischemia and Deterioration with Lower Blood Pressure Target in Intracranial Hemorrhage. Neurology. 2018;91:e1058-1066

Population:

• Adult patients with ICH

Outcomes:

• Primary:
  • Presence of acute cerebral ischemia on MRI completed within 2 weeks of ICH and acute neurologic deterioration
    • Acute neurologic deterioration defines as change in NIHSS ≥ 4 pts from admission NIHSS during any point in hospitalization
    • Acute cerebral ischemia was defined by restricted diffusion on DWI with corresponding ADC hypointensity remote to ICH location or any blood products.
• Secondary:
  • Identify predictors of acute ischemic lesions in patients with ICH
• Intervention:
  • Target SBP <140mmHg
    • Achieved acutely via IV nicardipine and subsequently oral BP meds within 24-72 hours to wean off IV.
    • No lower limits of SBP
    • Nurses to notify providers for MAP <65 mmHg
• Control:
  • Target SBP <160 mmHg
• Design:
  • Retrospective review
• Excluded:
  • those with ICH 2/2 trauma, vascular malformations, or tumors
  • those who underwent emergent surgical evacuation,
  • digital subtraction angiography prior to MRI,
  • if death or withdrawal of life sustaining therapy occurred within the first 72 hrs of admission.
  • those with increase in NIHSS due to seizures or sedation
  • those without documented NIHSS.

Primary Results:

• 286 patients with ICH; 119 underwent MRI and met inclusion criteria
  • consent
• 109 patients included for analysis
  • SBP <160 mmHg: n = 62
  • SBP <140 mmHg: n = 57

Secondary Results:

• 28 patients of the 119 found to have acute cerebral ischemia on MRI
  • More likely to have lobar hemorrhages
  • Baseline characteristics were similar
  • Had lower mean SBP over subsequent 24 hours and larger drop over the first 24 hours (no difference in avg SBP at admission)
  • No patient with minimum SBP ≥ 130 mmHg had evidence of cerebral ischemia on MRI

Critical Findings:

• Acute cerebral ischemia and acute neurologic deterioration was more frequent in SBP <140mmHg.
  • Persons with lower target SBP had a higher rate of cerebral ischemia, acute neurologic deterioration during hospitalization, and longer days spent in the neuro ICU and hospital.

Strengths:

• Asks a clinically important, patient centered question
• Study design allows suggestion of causation

Limitations:

• Single center, retrospective observational design with small n
• BP variability and range was not documented

Discussion:

• Aggressive BP lowering and larger changes in BP are associated with increased risk of cerebral ischemia.
• Reducing SBP <120 was a significant predictor of cerebral ischemia.
• Increased risk of AKI.
• Author’s Conclusions:
  • “We demonstrate that, after our institutional protocol change in SBP
    target from <160 to <140 mm Hg for acute ICH, there was an increased rate of cerebral ischemia and acute neurologic deterioration in persons with SBP target <140 mm Hg.”
• Our Conclusions:
  • This study appears to repeat the critical clinical practice that aggressive BP lowering in ICH leads to more harm;
  • However, appeared to elucidate that the lower limit goal
    SBP is perhaps 130 mmHg.
• Potential to Impact Current Practice:
  • This study repeats more of the same: Go slow with
    BP lowering.
• Clinical Bottom Line:
  • Aggressive BP lowering in ICH can cause harm.
• Additional Studies to check out:
  • Kidwell CS, Rosand J, Norato G, et al. Ischemic lesions, blood pressure dysregulation, and poor outcomes in intracerebral hemorrhage. Neurology 2017;88:782–788.