What is the recommended blood pressure target in the acute management of intracerebral hemorrhage based on the ATACH 2 (Antihypertensive Treatment of Acute Cerebral Hemorrhage 2) trial?

ATACH-2 Trial Blood Pressure Management in Intracerebral Hemorrhage

The ATACH-2 trial demonstrated that intensive blood pressure lowering to a systolic target of 110-139 mmHg did NOT improve outcomes compared to standard treatment (140-179 mmHg) and was associated with increased renal adverse events, leading current guidelines to recommend avoiding systolic BP <130 mmHg in acute ICH. 1

Key Trial Findings

The ATACH-2 trial enrolled 1,000 patients with acute intracerebral hemorrhage (ICH volume <60 cm³, GCS ≥5) and randomized them to intensive (SBP 110-139 mmHg) versus standard (SBP 140-179 mmHg) blood pressure reduction using IV nicardipine within 4.5 hours of symptom onset. 2

Primary outcome results:

• Death or disability (mRS 4-6) at 3 months occurred in 38.7% of intensive treatment patients versus 37.7% of standard treatment patients (no significant difference). 2
• The trial was stopped early for futility after interim analysis. 2

Safety concerns identified:

• Renal adverse events within 7 days were significantly higher with intensive treatment (9.0% vs 4.0%, P=0.002). 2
• Mean minimum SBP achieved in the intensive group was 129 mmHg, suggesting that lowering below 130 mmHg may negate potential benefits. 1

Current Guideline Recommendations Based on ATACH-2

For patients with mild to moderate ICH (GCS ≥5) presenting with SBP 150-220 mmHg:

• Target SBP range of 130-140 mmHg is safe and may improve functional outcomes. 1
• Initiate treatment within 2 hours of ICH onset and achieve target within 1 hour. 1, 3
• Avoid lowering SBP below 130 mmHg as this is potentially harmful. 1, 3

For patients with very high baseline SBP (≥220 mmHg):

• More cautious BP lowering is required, as post hoc analysis of ATACH-2 showed higher rates of neurological deterioration and renal adverse events without benefit in reducing hematoma expansion or improving outcomes. 1

Clinical Implications and Practical Application

Medication selection:

• IV nicardipine was used in ATACH-2, starting at 5 mg/hour with titration to achieve target. 1, 3
• Labetalol is an alternative first-line agent (5-20 mg IV bolus every 15 minutes or 2 mg/min infusion). 3, 4
• Any rapid-onset, short-duration antihypertensive allowing easy titration is appropriate. 1
• Avoid venous vasodilators (e.g., nitroprusside) due to potential negative effects on hemostasis and intracranial pressure. 1, 4

Monitoring requirements:

• Minimize SBP variability during the first 24 hours, as increased variability is associated with worse outcomes. 1
• Continuous BP monitoring is required for patients on IV antihypertensives. 3
• Frequent BP checks are essential to avoid large fluctuations. 3

Special Populations and Caveats

Moderate to severe ICH (GCS <13, NIHSS ≥10, ICH volume ≥30 mL, or IVH present):

• Post hoc analysis of 682 ATACH-2 patients showed intensive BP lowering reduced hematoma expansion (20.4% vs 27.9%) but did not reduce death or disability. 5
• For large ICH (>30 mL) requiring ICP monitoring, maintain cerebral perfusion pressure (CPP) 60-70 mmHg during BP reduction. 1, 4

Timing considerations:

• Mean time to treatment initiation in ATACH-2 was 182±57 minutes. 1
• Subgroup analysis suggested treatment within 2 hours of onset was associated with lower hematoma expansion risk and improved 90-day outcomes. 1

Common pitfalls to avoid:

• Excessive acute SBP drops (>70 mmHg) may cause acute renal injury and neurological deterioration. 4
• Achieving SBP <130 mmHg eliminates potential benefits and increases harm. 1
• Elevated baseline creatinine, ICH volume ≥25 mL, and higher nicardipine doses increase acute kidney injury risk. 1