The Intracerebral Haemorrhage Acutely Decreasing Arterial Pressure Trial: ICH ADAPT

European Stroke Organisation (ESO) guidelines on blood pressure management in acute ischaemic stroke and intracerebral haemorrhage

The optimal blood pressure (BP) management in acute ischaemic stroke (AIS) and acute intracerebral haemorrhage (ICH) remains controversial. These European Stroke Organisation (ESO) guidelines provide evidence-based recommendations to assist physicians in their clinical decisions regarding BP management in acute stroke.The guidelines were developed according to the ESO standard operating procedure and Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) methodology. The working group identified relevant clinical questions, performed systematic reviews and meta-analyses of the literature, assessed the quality of the available evidence, and made specific recommendations. Expert consensus statements were provided where insufficient evidence was available to provide recommendations based on the GRADE approach. Despite several large randomised-controlled clinical trials, quality of evidence is generally low due to inconsistent results of the effect of blood pressure lowering in AIS. We recommend early and modest blood pressure control (avoiding blood pressure levels >180/105 mm Hg) in AIS patients undergoing reperfusion therapies. There is more high-quality randomised evidence for BP lowering in acute ICH, where intensive blood pressure lowering is recommended rapidly after hospital presentation with the intent to improve recovery by reducing haematoma expansion. These guidelines provide further recommendations on blood pressure thresholds and for specific patient subgroups. There is ongoing uncertainty regarding the most appropriate blood pressure management in AIS and ICH. Future randomised-controlled clinical trials are needed to inform decision making on thresholds, timing and strategy of blood pressure lowering in different acute stroke patient subgroups.

Hemorrhagic stroke

Hemorrhagic stroke comprises about 20% of all strokes, with intracerebral hemorrhage (ICH) being the most common type. Frequency of ICH is increased where hypertension is untreated. ICH in particularly has a disproportionately high risk of early mortality and long-term disability. Until recently, there has been a paucity of randomized controlled trials (RCTs) to provide evidence for the efficacy of various commonly considered interventions in ICH, including acute blood pressure management, coagulopathy reversal, and surgical hematoma evacuation. Evidence-based guidelines do exist for ICH and these form the basis for a framework of care. Current approaches emphasize control of extremely high blood pressure in the acute phase, rapid reversal of vitamin K antagonists, and surgical evacuation of cerebellar hemorrhage. Lingering questions, many of which are the topic of ongoing clinical research, include optimizing individual blood pressure targets, reversal strategies for newer anticoagulant medications, and the role of minimally invasive surgery. Risk stratification models exist, which derive from findings on clinical exam and neuroimaging, but care should be taken to avoid a self-fulfilling prophecy of poor outcome from limiting treatment due to a presumed poor prognosis. Cerebral venous thrombosis is an additional subtype of hemorrhagic stroke that has a unique set of causes, natural history, and treatment and is discussed as well.

Lowering blood pressure after acute intracerebral haemorrhage: protocol for a systematic review and meta-analysis using individual patient data from randomised controlled trials participating in the Blood Pressure in Acute Stroke Collaboration (BASC)

INTRODUCTION

Conflicting results from multiple randomised trials indicate that the methods and effects of blood pressure (BP) reduction after acute intracerebral haemorrhage (ICH) are complex. The Blood pressure in Acute Stroke Collaboration is an international collaboration, which aims to determine the optimal management of BP after acute stroke including ICH.

METHODS AND ANALYSIS

A systematic review will be undertaken according to the Preferred Reporting Items for Systematic review and Meta-Analysis of Individual Participant Data (IPD) guideline. A search of Cochrane Central Register of Controlled Trials, EMBASE and MEDLINE from inception will be conducted to identify randomised controlled trials of BP management in adults with acute spontaneous (non-traumatic) ICH enrolled within the first 7 days of symptom onset. Authors of studies that meet the inclusion criteria will be invited to share their IPD. The primary outcome will be functional outcome according to the modified Rankin Scale. Safety outcomes will be early neurological deterioration, symptomatic hypotension and serious adverse events. Secondary outcomes will include death and neuroradiological and haemodynamic variables. Meta-analyses of pooled IPD using the intention-to-treat dataset of included trials, including subgroup analyses to assess modification of the effects of BP lowering by time to treatment, treatment strategy and patient's demographic, clinical and prestroke neuroradiological characteristics.

ETHICS AND DISSEMINATION

No new patient data will be collected nor is there any deviation from the original purposes of each study where ethical approvals were granted; therefore, further ethical approval is not required. Results will be reported in international peer-reviewed journals.

PROSPERO REGISTRATION NUMBER

CRD42019141136.

Aggressive blood pressure reduction is not associated with decreased perfusion in leukoaraiosis regions in acute intracerebral hemorrhage patients

Leukoaraiosis regions may be more vulnerable to decreases in cerebral perfusion. We aimed to assess perfusion in leukoaraiosis regions in acute intracerebral hemorrhage (ICH) patients. We tested the hypothesis that aggressive acute BP reduction in ICH patients is associated with hypoperfusion in areas of leukoaraiosis. In the ICH Acutely Decreasing Arterial Pressure Trial (ICH ADAPT), patients with ICH <24 hours duration were randomized to two systolic BP (SBP) target groups (<150 mmHg vs. <180 mmHg). Computed tomography perfusion (CTP) imaging was performed 2h post-randomization. Leukoaraiosis tissue volumes were planimetrically measured using semi-automated threshold techniques on the acute non-contrast CT. CTP source leukoaraiosis region-of-interest object maps were co-registered with CTP post-processed maps to assess cerebral perfusion in these areas. Seventy-one patients were included with a mean age of 69±11.4 years, 52 of whom had leukoaraiosis. The mean relative Tmax (rTmax) of leukoaraiotic tissue (2.3±2s) was prolonged compared to that of normal appearing white matter in patients without leukoaraiosis (1.1±1.2s, p = 0.04). In the 52 patients with leukoaraiosis, SBP in the aggressive treatment group (145±20.4 mmHg, n = 27) was significantly lower than that in the conservative group (159.9±13.1 mmHg, n = 25, p = 0.001) at the time of CTP. Despite this SBP difference, mean leukoaraiosis rTmax was similar in the two treatment groups (2.6±2.3 vs. 1.8±1.6 seconds, p = 0.3). Cerebral perfusion in tissue affected by leukoaraiosis is hypoperfused in acute ICH patients. Aggressive BP reduction does not appear to acutely aggravate cerebral hypoperfusion.

The Effect of Cerebrovascular Stenosis on -Peri-Hematoma Cerebral Perfusion and Clinical Outcomes in Patients with Supratentorial Spontaneous Intracerebral Hemorrhage

Background

Many factors are associated with the cerebral hypoperfusion after spontaneous intracerebral hemorrhage (sICH), however, the effect of cerebrovascular stenosis on peri-hematoma cerebral blood flow (CBF) and 90-day poor outcomes in patients with spontaneous intracerebral hemorrhage is still unclear.

Material/Methods

From September 2016 to March 2017, we prospectively collected data on adults with supratentorial spontaneous intracerebral hemorrhages. Using the Propensity Score model, we compared the peri-hematoma CBF and 90-day poor outcomes (mRS ≥3) in the stenosis group and the control group.

Results

Before matching, a total of 116 patients were included in this study, 25 patients in the stenosis group and 91 patients in the control group. After matching, the patients in the stenosis group had a higher absolute decrease of CBF (p=0.003), higher relative decrease of CBF (p=0.016), and higher incidence of 90-day poor outcomes (p=0.041) than the control group. With subgroup analysis, the patients with Glasgow Coma Scale from 13 to 15 (p=0.035), hematoma in the cerebral lobe (p=0.003), mean arterial pressure lower than 120 mm Hg (p=0.003), absolute decrease of CBF higher than 15 mL/100 g per minute (p=0.007), and relative decrease of CBF higher than 30% (p=0.020) had poorer outcomes.

Conclusions

In our series, the stenosis of main cerebral vessels decreased the peri-hematoma CBF and increased the rate of 90-day poor outcomes. Despite higher Glasgow Coma Scale, the evaluation of cerebral perfusion in patients with sICH is needed, especially for the patients with hematoma in the cerebral lobe and lower mean arterial pressure; and treatments to keep adequate cerebral perfusion are needed.

Preclinical Studies and Translational Applications of Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) which refers to bleeding in the brain is a very deleterious condition with high mortality and disability rate. Surgery or conservative therapy remains the treatment option. Various studies have divided the disease process of ICH into primary and secondary injury, for which knowledge into these processes has yielded many preclinical and clinical treatment options. The aim of this review is to highlight some of the new experimental drugs as well as other treatment options like stem cell therapy, rehabilitation, and nanomedicine and mention some translational clinical applications that have been done with these treatment options.

Subarachnoid Hemorrhage: An Update

Subarachnoid hemorrhage (SAH) is a debilitating, although uncommon, type of stroke with high morbidity, mortality, and economic impact. Modern 30-day mortality is as high as 40%, and about 50% of survivors have permanent disability. Care at high-volume centers with dedicated neurointensive care units is recommended. Euvolemia, not hypervolemia, should be targeted, and the aneurysm should be secured early. Neither statin therapy nor magnesium infusions should be initiated for delayed cerebral ischemia. Cerebral vasospasm is just one component of delayed cerebral edema. Hyponatremia is common in subarachnoid hemorrhage and is associated with longer length of stay, but not increased mortality.

High Postoperative Blood Pressure After Cardiac Surgery Is Associated With Acute Kidney Injury and Death

OBJECTIVES

Gaps and uncertainty exist regarding the understanding of optimal clinical goals for perioperative (ie, preoperative, intraoperative, and postoperative) blood pressure (BP) management in patients undergoing cardiac surgery and the consequences of achieving or failing to achieve those goals. In this setting, it is understood that preoperative hypertension is predictive of poor postoperative outcomes, with a growing appreciation that current, clinically acceptable changes in intraoperative BP also may be associated independently with adverse short- and long-term outcomes. In contrast, the impact of postoperative BP on outcomes after cardiac surgery remains less clear.

DESIGN

This study was a retrospective outcome analysis.

SETTING

The study included all cardiac surgery patients cared for at a single institution over a 7-year period. Consequences of the success or failure of meeting postoperative BP targets on medical outcomes and health resource utilization were evaluated.

RESULTS

The study comprised 5,225 patients. Hypertensive postoperative patients experienced a higher in-hospital mortality rate compared with matched-case normotensive patients (4.97% v 1.32%, p<0.001) and a longer hospital stay (p = 0.024). In hypertensive patients, serum creatinine levels from postoperative day 1 through postoperative day 7 were increased compared with baseline and postoperative renal dysfunction according to the Kidney Disease: Improving Global Outcomes criteria occurred significantly more often (25.3% v 19.7%, p = 0.027).

CONCLUSIONS

Postoperative hypertension is associated with compromised outcome as reflected by higher mortality, longer length of stay, and higher incidence of renal dysfunction.

Cerebral Perfusion Pressure is Maintained in Acute Intracerebral Hemorrhage: A CT Perfusion Study

BACKGROUND AND PURPOSE

Although blood pressure reduction has been postulated to result in a fall in cerebral perfusion pressure in patients with intracerebral hemorrhage, the latter is rarely measured. We assessed regional cerebral perfusion pressure in patients with intracerebral hemorrhage by using CT perfusion source data.

MATERIALS AND METHODS

Patients with acute primary intracerebral hemorrhage were randomized to target systolic blood pressures of <150 mm Hg (n = 37) or <180 mm Hg (n = 36). Regional maps of cerebral blood flow, cerebral perfusion pressure, and cerebrovascular resistance were generated by using CT perfusion source data, obtained 2 hours after randomization.

RESULTS

Perihematoma cerebral blood flow (38.7 ± 11.9 mL/100 g/min) was reduced relative to contralateral regions (44.1 ± 11.1 mL/100 g/min, P = .001), but cerebral perfusion pressure was not (14.4 ± 4.6 minutes(-1) versus 14.3 ± 4.8 minutes(-1), P = .93). Perihematoma cerebrovascular resistance (0.34 ± 0.11 g/mL) was higher than that in the contralateral region (0.30 ± 0.10 g/mL, P < .001). Ipsilateral and contralateral cerebral perfusion pressure in the external (15.0 ± 4.6 versus 15.6 ± 5.3 minutes(-1), P = .15) and internal (15.0 ± 4.8 versus 15.0 ± 4.8 minutes(-1), P = .90) borderzone regions were all similar. Borderzone cerebral perfusion pressure was similar to mean global cerebral perfusion pressure (14.7 ± 4.7 minutes(-1), P ≥ .29). Perihematoma cerebral perfusion pressure did not differ between blood pressure treatment groups (13.9 ± 5.5 minutes(-1) versus 14.8 ± 3.4 minutes(-1), P = .38) or vary with mean arterial pressure (r = -0.08, [-0.10, 0.05]).

CONCLUSIONS

Perihematoma cerebral perfusion pressure is maintained despite increased cerebrovascular resistance and reduced cerebral blood flow. Aggressive antihypertensive therapy does not affect perihematoma or borderzone cerebral perfusion pressure. Maintenance of cerebral perfusion pressure provides physiologic support for the safety of blood pressure reduction in intracerebral hemorrhage.

Perihematoma cerebral blood flow is unaffected by statin use in acute intracerebral hemorrhage patients

Statin therapy has been associated with improved cerebral blood flow (CBF) and decreased perihematoma edema in animal models of intracerebral hemorrhage (ICH). We aimed to assess the relationship between statin use and cerebral hemodynamics in ICH patients. A post hoc analysis of 73 ICH patients enrolled in the Intracerebral Hemorrhage Acutely Decreasing Arterial Pressure Trial (ICH ADAPT). Patients presenting <24 hours from ICH onset were randomized to a systolic blood pressure target <150 or <180 mm Hg with computed tomography perfusion imaging 2 hours after randomization. Cerebral blood flow maps were calculated. Hematoma and edema volumes were measured planimetrically. Regression models were used to assess the relationship between statin use, perihematoma edema and cerebral hemodynamics. Fourteen patients (19%) were taking statins at the time of ICH. Statin-treated patients had similar median (IQR Q25 to 75) hematoma volumes (21.1 (9.5 to 38.3) mL versus 14.5 (5.6 to 27.7) mL, P=0.25), but larger median (IQR Q25 to 75) perihematoma edema volumes (2.9 (1.7 to 9.0) mL versus 2.2 (0.8 to 3.5) mL, P=0.02) compared with nontreated patients. Perihematoma and ipsilateral hemispheric CBF were similar in both groups. A multivariate linear regression model revealed that statin use and hematoma volumes were independent predictors of acute edema volumes. Statin use does not affect CBF in ICH patients. Statin use, along with hematoma volume, are independently associated with increased perihematoma edema volume.

Aneurysmal Subarachnoid Hemorrhage

Aneurysmal subarachnoid hemorrhage (SAH) is a worldwide health burden with high fatality and permanent disability rates. The overall prognosis depends on the volume of the initial bleed, rebleeding, and degree of delayed cerebral ischemia (DCI). Cardiac manifestations and neurogenic pulmonary edema indicate the severity of SAH. The International Subarachnoid Aneurysm Trial (ISAT) reported a favorable neurological outcome with the endovascular coiling procedure compared with surgical clipping at the end of 1 year. The ISAT trial recruits were primarily neurologically good grade patients with smaller anterior circulation aneurysms, and therefore the results cannot be reliably extrapolated to larger aneurysms, posterior circulation aneurysms, patients presenting with complex aneurysm morphology, and poor neurological grades. The role of hypothermia is not proven to be neuroprotective according to a large randomized controlled trial, Intraoperative Hypothermia for Aneurysms Surgery Trial (IHAST II), which recruited patients with good neurological grades. Patients in this trial were subjected to slow cooling and inadequate cooling time and were rewarmed rapidly. This methodology would have reduced the beneficial effects of hypothermia. Adenosine is found to be beneficial for transient induced hypotension in 2 retrospective analyses, without increasing the risk for cardiac and neurological morbidity. The neurological benefit of pharmacological neuroprotection and neuromonitoring is not proven in patients undergoing clipping of aneurysms. DCI is an important cause of morbidity and mortality following SAH, and the pathophysiology is likely multifactorial and not yet understood. At present, oral nimodipine has an established role in the management of DCI, along with maintenance of euvolemia and induced hypertension. Following SAH, hypernatremia, although less common than hyponatremia, is a predictor of poor neurological outcome.

Blood-brain barrier compromise does not predict perihematoma edema growth in intracerebral hemorrhage

BACKGROUND AND PURPOSE

There are limited data on the extent of blood-brain barrier (BBB) compromise in acute intracerebral hemorrhage patients. We tested the hypotheses that BBB compromise measured with permeability-surface area product (PS) is increased in the perihematoma region and predicts perihematoma edema growth in acute intracerebral hemorrhage patients.

METHODS

Patients were randomized within 24 hours of symptom onset to a systolic blood pressure (SBP) treatment of <150 (n=26) or <180 mm Hg (n=27). Permeability maps were generated using computed tomographic perfusion source data acquired 2 hours after randomization, and mean PS was measured in the hematoma, perihematoma, and hemispheric regions. Hematoma and edema volumes were measured on noncontrast computed tomographic scans obtained at baseline, 2 hours and 24 hours after randomization.

RESULTS

Patients were randomized at a median (interquartile range) time of 9.3 hours (14.1) from symptom onset. Treatment groups were balanced with respect to baseline SBP and hematoma volume. Perihematoma PS (5.1±2.4 mL/100 mL per minute) was higher than PS in contralateral regions (3.6±1.7 mL/100 mL per minute; P<0.001). Relative edema growth (0-24 hours) was not predicted by perihematoma PS (β=-0.192 [-0.06 to 0.01]) or SBP change (β=-0.092 [-0.002 to 0.001]). SBP was lower in the <150 target group (139.2±22.1 mm Hg) than in the <180 group (159.7±12.3 mm Hg; P<0.0001). Perihematoma PS was not different between groups (4.9±2.4 mL/100 mL per minute for the <150 group, 5.3±2.4 mL/100 mL per minute for the <180 group; P=0.51).

CONCLUSIONS

BBB permeability is focally increased in the hematoma and perihematoma regions of acute intracerebral hemorrhage patients. BBB compromise does not predict acute perihematoma edema volume or edema growth. SBP reduction does not affect BBB permeability.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT00963976.

Interventions for deliberately altering blood pressure in acute stroke

BACKGROUND

It is unclear whether blood pressure should be altered actively during the acute phase of stroke. This is an update of a Cochrane review first published in 1997, and previously updated in 2001 and 2008.

OBJECTIVES

To assess the clinical effectiveness of altering blood pressure in people with acute stroke, and the effect of different vasoactive drugs on blood pressure in acute stroke.

SEARCH METHODS

We searched the Cochrane Stroke Group Trials Register (last searched in February 2014), the Cochrane Database of Systematic reviews (CDSR) and the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2014, Issue 2), MEDLINE (Ovid) (1966 to May 2014), EMBASE (Ovid) (1974 to May 2014), Science Citation Index (ISI, Web of Science, 1981 to May 2014) and the Stroke Trials Registry (searched May 2014).

SELECTION CRITERIA

Randomised controlled trials of interventions that aimed to alter blood pressure compared with control in participants within one week of acute ischaemic or haemorrhagic stroke.

DATA COLLECTION AND ANALYSIS

Two review authors independently applied the inclusion criteria, assessed trial quality and extracted data. The review authors cross-checked data and resolved discrepancies by discussion to reach consensus. We obtained published and unpublished data where available.

MAIN RESULTS

We included 26 trials involving 17,011 participants (8497 participants were assigned active therapy and 8514 participants received placebo/control). Not all trials contributed to each outcome. Most data came from trials that had a wide time window for recruitment; four trials gave treatment within six hours and one trial within eight hours. The trials tested alpha-2 adrenergic agonists (A2AA), angiotensin converting enzyme inhibitors (ACEI), angiotensin receptor antagonists (ARA), calcium channel blockers (CCBs), nitric oxide (NO) donors, thiazide-like diuretics, and target-driven blood pressure lowering. One trial tested phenylephrine.At 24 hours after randomisation oral ACEIs reduced systolic blood pressure (SBP, mean difference (MD) -8 mmHg, 95% confidence interval (CI) -17 to 1) and diastolic blood pressure (DBP, MD -3 mmHg, 95% CI -9 to 2), sublingual ACEIs reduced SBP (MD -12.00 mm Hg, 95% CI -26 to 2) and DBP (MD -2, 95%CI -10 to 6), oral ARA reduced SBP (MD -1 mm Hg, 95% CI -3 to 2) and DBP (MD -1 mm Hg, 95% CI -3 to 1), oral beta blockers reduced SBP (MD -14 mm Hg; 95% CI -27 to -1) and DBP (MD -1 mm Hg, 95% CI -9 to 7), intravenous (iv) beta blockers reduced SBP (MD -5 mm Hg, 95% CI -18 to 8) and DBP (-5 mm Hg, 95% CI -13 to 3), oral CCBs reduced SBP (MD -13 mmHg, 95% CI -43 to 17) and DBP (MD -6 mmHg, 95% CI -14 to 2), iv CCBs reduced SBP (MD -32 mmHg, 95% CI -65 to 1) and DBP (MD -13, 95% CI -31 to 6), NO donors reduced SBP (MD -12 mmHg, 95% CI -19 to -5) and DBP (MD -3, 95% CI -4 to -2) while phenylephrine, non-significantly increased SBP (MD 21 mmHg, 95% CI -13 to 55) and DBP (MD 1 mmHg, 95% CI -15 to 16).Blood pressure lowering did not reduce death or dependency either by drug class (OR 0.98, 95% CI 0.92 to 1.05), stroke type (OR 0.98, 95% CI 0.92 to 1.05) or time to treatment (OR 0.98, 95% CI 0.92 to 1.05). Treatment within six hours of stroke appeared effective in reducing death or dependency (OR 0.86, 95% CI 0.76 to 0.99) but not death (OR 0.70, 95% CI 0.38 to 1.26) at the end of the trial. Although death or dependency did not differ between people who continued pre-stroke antihypertensive treatment versus those who stopped it temporarily (worse outcome with continuing treatment, OR 1.06, 95% CI 0.91 to 1.24), disability scores at the end of the trial were worse in participants randomised to continue treatment (Barthel Index, MD -3.2, 95% CI -5.8, -0.6).

AUTHORS' CONCLUSIONS

There is insufficient evidence that lowering blood pressure during the acute phase of stroke improves functional outcome. It is reasonable to withhold blood pressure-lowering drugs until patients are medically and neurologically stable, and have suitable oral or enteral access, after which drugs can than be reintroduced. In people with acute stroke, CCBs, ACEI, ARA, beta blockers and NO donors each lower blood pressure while phenylephrine probably increases blood pressure. Further trials are needed to identify which people are most likely to benefit from early treatment, in particular whether treatment started very early is beneficial.

Acute blood pressure reduction in patients with intracerebral hemorrhage does not result in borderzone region hypoperfusion

BACKGROUND AND PURPOSE

The Intracerebral Hemorrhage Acutely Decreasing Arterial Pressure Trial (ICH ADAPT) demonstrated blood pressure (BP) reduction does not affect mean perihematoma or hemispheric cerebral blood flow. Nonetheless, portions of the perihematoma and borderzones may reach ischemic thresholds after BP reduction. We tested the hypothesis that BP reduction after intracerebral hemorrhage results in increased critically hypoperfused tissue volumes.

METHODS

Patients with Intracerebral hemorrhage were randomized to a target systolic BP (SBP) of <150 or <180 mm Hg and imaged with computed tomographic perfusion 2 hours later. The volumes of tissue below cerebral blood flow thresholds for ischemia (<18 mL/100 g/min) and infarction (<12 mL/100 g/min) were calculated as a percentage of the total volume within the internal and external borderzones and the perihematoma region.

RESULTS

Seventy-five patients with intracerebral hemorrhage were randomized a median (interquartile range) of 7.8 (13.3) hours from onset. Acute hematoma volume was 17.8 (27.1) mL and mean SBP was 183±22 mm Hg. At the time of computed tomographic perfusion (2.3 [1.0] hours after randomization), SBP was lower in the <150 mm Hg (n=37; 140±18 mm Hg) than in the <180 mm Hg group (n=36; 162±12 mm Hg; P<0.001). BP treatment did not affect the percentage of total borderzone tissue with cerebral blood flow<18 (14.7±13.6 versus 15.6±13.7%; P=0.78) or <12 mL/100 g/min (5.1±5.1 versus 5.8±6.8%; P=0.62). Similar results were found in the perihematoma region. Low SBP load (fraction of time with SBP<150 mmHg) did not predict borderzone tissue volume with cerebral blood flow<18 mL/100 g/min (β=0.023 [-0.073, 0.119]).

CONCLUSIONS

BP reduction does not increase the volume of critically hypoperfused borderzone or perihematoma tissue. These data support the safety of early BP reduction in intracerebral hemorrhage.

CLINICAL TRIAL REGISTRATION URL

http://www.clinicaltrials.gov. Unique identifier: NCT00963976.

Progress in translational research on intracerebral hemorrhage: is there an end in sight?

Intracerebral hemorrhage (ICH) is a common and often fatal stroke subtype for which specific therapies and treatments remain elusive. To address this, many recent experimental and translational studies of ICH have been conducted, and these have led to several ongoing clinical trials. This review focuses on the progress of translational studies of ICH including those of the underlying causes and natural history of ICH, animal models of the condition, and effects of ICH on the immune and cardiac systems, among others. Current and potential clinical trials also are discussed for both ICH alone and with intraventricular extension.

Blood pressure reduction does not reduce perihematoma oxygenation: a CT perfusion study

Blood pressure (BP) reduction after intracerebral hemorrhage (ICH) is controversial, because of concerns that this may cause critical reductions in perihematoma perfusion and thereby precipitate tissue damage. We tested the hypothesis that BP reduction reduces perihematoma tissue oxygenation.Acute ICH patients were randomized to a systolic BP target of <150 or <180 mm Hg. Patients underwent CT perfusion (CTP) imaging 2 hours after randomization. Maps of cerebral blood flow (CBF), maximum oxygen extraction fraction (OEF(max)), and the resulting maximum cerebral metabolic rate of oxygen (CMRO2(max)) permitted by local hemodynamics, were calculated from raw CTP data.Sixty-five patients (median (interquartile range) age 70 (20)) were imaged at a median (interquartile range) time from onset to CTP of 9.8 (13.6) hours. Mean OEF(max) was elevated in the perihematoma region (0.44±0.12) relative to contralateral tissue (0.36±0.11; P<0.001). Perihematoma CMRO2(max) (3.40±1.67 mL/100 g per minute) was slightly lower relative to contralateral tissue (3.63±1.66 mL/100 g per minute; P=0.025). Despite a significant difference in systolic BP between the aggressive (140.5±18.7 mm Hg) and conservative (163.0±10.6 mm Hg; P<0.001) treatment groups, perihematoma CBF was unaffected (37.2±11.9 versus 35.8±9.6 mL/100 g per minute; P=0.307). Similarly, aggressive BP treatment did not affect perihematoma OEF(max) (0.43±0.12 versus 0.45±0.11; P=0.232) or CMRO2(max) (3.16±1.66 versus 3.68±1.85 mL/100 g per minute; P=0.857). Blood pressure reduction does not affect perihematoma oxygen delivery. These data support the safety of early aggressive BP treatment in ICH.

Eligibility for randomized trials of treatments specifically for intracerebral hemorrhage: community-based study

BACKGROUND AND PURPOSE

Acute treatments specifically for intracerebral hemorrhage (ICH) are being sought in randomized controlled trials. The treatment effect sizes in ongoing and future trials are likely to be small, necessitating large sample sizes.

METHODS

We searched online trial registries for randomized controlled trials investigating an acute treatment for ICH. For the trials whose eligibility criteria could be assessed in a prospective, community-based ICH cohort study (2010-2011), we quantified the proportions of patients who were eligible and investigated influences on these proportions.

RESULTS

We applied the eligibility criteria of 17 trials to 166 adults with ICH, of whom between 0.6% (95% confidence interval, 0.1-3.3) to 40% (95% confidence interval, 33-48) were eligible for each trial. Fewer patients were eligible for trials restricted to patients randomized within 12 hours of ICH onset (versus trials with a longer time window; P=0.03) and trials restricting eligibility according to premorbid disability (versus trials without this restriction; P=0.046). Each additional eligibility criterion reduced the portion of eligible patients by 1.3% (95% confidence interval, 0.4-2.2; adjusted R(2)=0.47; P=0.004).

CONCLUSIONS

Less than half of patients with ICH were eligible for current randomized controlled trials. Future trials could maximize enrollment by minimizing the number of eligibility criteria, maximizing the time window for recruiting patients after ICH onset, permitting premorbid disability, and using a simulator to assess the impact of other eligibility critiera (www.dcn.ed.ac.uk/ICHsimulator/).

Autoregulation of Cerebral Blood Flow is Preserved in Primary Intracerebral Hemorrhage

Background and Purpose—

Treatment of acute hypertension after intracerebral hemorrhage (ICH) is controversial. In the context of disrupted cerebral autoregulation, blood pressure (BP) reduction may cause decreased cerebral blood flow (CBF). We used serial computed tomography perfusion to test the hypothesis that CBF remains stable after BP reduction.

Methods—

Patients recruited within 72 hours of ICH were imaged with computed tomography perfusion before and after BP treatment. Change in perihematoma relative (r) CBF after BP treatment was the primary end point.

Results—

Twenty patients were imaged with computed tomography perfusion at a median (interquartile range) time from onset of 20.2 (25.7) hours and reimaged 2.1 (0.5) hours later, after BP reduction. Mean systolic BP in treated patients (n=16; 4 untreated as BP<target at baseline) decreased significantly between the first (168±21 mm Hg) and second (141±19 mm Hg; P <0.0001) computed tomography perfusion scans. The primary end point of rCBF was not affected by BP reduction (pretreatment=0.89±0.11; post-treatment=0.87±0.11 mL/100 g per minute; P =0.37). Linear regression showed no relationship between changes in systolic BP and perihematoma rCBF (β=0.001 [−0.002 to 0.003]; P =0.63).

Conclusions—

CBF remained stable after acute BP reduction, suggesting some preservation of cerebral autoregulation.

The Intracerebral Hemorrhage Acutely Decreasing Arterial Pressure Trial

BACKGROUND AND PURPOSE

Acute blood pressure (BP) reduction aimed at attenuation of intracerebral hemorrhage (ICH) expansion might also compromise cerebral blood flow (CBF). We tested the hypothesis that CBF in acute ICH patients is unaffected by BP reduction.

METHODS

Patients with spontaneous ICH <24 hours after onset and systolic BP > 150 mm Hg were randomly assigned to an intravenous antihypertensive treatment protocol targeting a systolic BP of <150 mm Hg (n=39) or <180 mm Hg (n=36). Patients underwent computed tomography perfusion imaging 2 hours postrandomization. The primary end point was perihematoma relative (relative CBF).

RESULTS

Treatment groups were balanced with respect to baseline systolic BP: 182±20 mm Hg (<150 mm Hg target group) versus 184±25 mm Hg (<180 mm Hg target group; P=0.60), and for hematoma volume: 25.6±30.8 versus 26.9±25.2 mL (P=0.66). Mean systolic BP 2 hours after randomization was significantly lower in the <150 mm Hg target group (140±19 vs 162±12 mm Hg; P<0.001). Perihematoma CBF (38.7±11.9 mL/100 g per minute) was lower than in contralateral homologous regions (44.1±11.1 mL/100 g per minute; P<0.001) in all patients. The primary end point of perihematoma relative CBF in the <150 mm Hg target group (0.86±0.12) was not significantly lower than that in the <180 mm Hg group (0.89±0.09; P=0.19; absolute difference, 0.03; 95% confidence interval -0.018 to 0.078). There was no relationship between the magnitude of BP change and perihematoma relative CBF in the <150 mm Hg (R=0.00005; 95% confidence interval, -0.001 to 0.001) or <180 mm Hg target groups (R=0.000; 95% confidence interval, -0.001 to 0.001).

CONCLUSIONS

Rapid BP lowering after a moderate volume of ICH does not reduce perihematoma CBF. These physiological data indicate that acute BP reduction does not precipitate cerebral ischemia in ICH patients. Clinical Trial Registration Information- URL:http://clinicaltrials.gov. Unique Identifier: NCT00963976.

Intracranial hemorrhage

Intracranial hemorrhage refers to any bleeding within the intracranial vault, including the brain parenchyma and surrounding meningeal spaces. This article focuses on the acute diagnosis and management of primary nontraumatic intracerebral hemorrhage and subarachnoid hemorrhage in the emergency department.

Blood pressure control for acute ischemic and hemorrhagic stroke

PURPOSE OF REVIEW

Acute stroke, including the subtypes of ischemic stroke, intracerebral hemorrhage (ICH), and subarachnoid hemorrhage (SAH), typically involves significant fluctuations in blood pressure (BP). Treatment of BP after all stroke types is controversial. In each case, there are theoretical dangers to leaving BP alone as well as altering it artificially. In this article, we review the role of BP in each stroke subtype and the existing evidence for BP optimization.

RECENT FINDINGS

Except in patients receiving thrombolytic therapy, there is insufficient evidence to recommend active BP management in ischemic stroke. In ICH, the Antihypertensive Treatment of Acute Cerebral Hemorrhage (ATACH) trial and Intensive Blood Pressure Reduction in Acute Cerebral Haemorrhage Trial (INTERACT) have demonstrated that systolic BP reduction to 140  mmHg is well tolerated and associated with attenuation of hematoma expansion. The impact of BP reduction on outcomes is being evaluated in the ongoing phase III ATACH II and INTERACT 2 trials. No evidence exists to recommend definitive BP management strategies in acute SAH, although hypertension should likely be avoided before an aneurysm is secured, and hypotension should be avoided altogether.

SUMMARY

Evidence for BP management in acute stroke is limited, although large randomized trials are currently in progress for both ischemic stroke and ICH. BP management in SAH remains woefully understudied.

Intracerebral haemorrhage: mechanisms of injury and therapeutic targets

Intracerebral haemorrhage accounts for about 10-15% of all strokes and is associated with high mortality and morbidity. No successful phase 3 clinical trials for this disorder have been completed. In the past 6 years, the number of preclinical and clinical studies focused on intracerebral haemorrhage has risen. Important advances have been made in animal models of this disorder and in our understanding of mechanisms underlying brain injury after haemorrhage. Several therapeutic targets have subsequently been identified that are now being pursued in clinical trials. Many clinical trials have been based on limited preclinical data, and guidelines to justify taking preclinical results to the clinic are needed.

Blood pressure management in acute intracerebral haemorrhage guidelines are poorly implemented in clinical practice

BACKGROUND

Optimal management of blood pressure (BP) in spontaneous intracerebral haemorrhage (ICH) is controversial. We assessed adherence to BP guidelines and its management in ICH in a tertiary Canadian Stroke Centre.

METHODS

We conducted a retrospective analysis of 142 CT confirmed primary ICH patients admitted within 24h of symptoms between 2005 and 2006. Initial practice with respect to BP control was reviewed and compared with current guidelines. This retrospective sample was compared with a prospective cohort participating in a BP lowering trial for the attainment of pre-defined BP targets. We also assessed the effect of BP treatment on hematoma expansion and mortality.

RESULTS

Blood pressure treatment orders were established in 73% of the 142 patients (median age 71 years, 61% male). Only 26% of patients had target orders as advised in the current AHA guidelines. Only 54% achieved BP targets as compared with 83% of the prospective cohort within 1h. Patients with established BP orders were more likely to have repeat brain imaging (70.2%) than those without (39.5%; p=0.001 Mortality rates were 29.8% and 47.4% in those with and without BP targets respectively (p=0.051).

CONCLUSIONS

Management of BP varies considerably and there appears to be little adherence to recommended guidelines. Targets are achieved more rapidly if a BP treatment protocol is utilized.