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

Acute Hypertensive Response in Patients With Acute Intracerebral Hemorrhage: A Narrative Review

OBJECTIVE

To review the role of the acute hypertensive response in patients with intracerebral hemorrhage, current treatment options, and areas for further research.

METHODS

Review of the literature to assess 1) frequency of acute hypertensive response in intracerebral hemorrhage; 2) consequences of acute hypertensive response in clinical outcomes; 3) acute hypertensive response and secondary brain injury: hematoma expansion and perihematomal edema; 4) vascular autoregulation, safety data side effects of acute antihypertensive treatment; and 5) randomized clinical trials and meta-analyses.

RESULTS

An acute hypertensive response is frequent in patients with acute intracerebral hemorrhage and is associated with poor clinical outcomes. However, it is not clear whether high blood pressure is a cause of poor clinical outcome or solely represents a marker of severity. Although current guidelines recommend intensive blood pressure treatment (<140 mm Hg) in patients with intracerebral hemorrhage, 2 randomized clinical trials have failed to demonstrate a consistent clinical benefit from this approach, and new data suggest that intensive blood pressure treatment could be beneficial for some patients but detrimental for others.

CONCLUSIONS

Intracerebral hemorrhage is a heterogenous disease, thus, a one-fit-all approach for blood pressure treatment may be suboptimal. Further research should concentrate on finding subgroups of patients more likely to benefit from aggressive blood pressure lowering, considering intracerebral hemorrhage etiology, ultra-early randomization, and risk markers of hematoma expansion on brain imaging.

Acute Blood Pressure and Outcome After Intracerebral Hemorrhage: The VISTA-ICH Cohort

BACKGROUND

Recent clinical trials suggest that it is safe to acutely lower systolic blood pressure (BP) to 140 mm Hg after ICH, but uncertainty remains regarding optimal management. We sought to better define the link between BP and outcome in ICH patients using data from the Virtual International Stroke Trials Archive (VISTA).

METHODS

We performed a retrospective analysis of patients of the VISTA-ICH trials. We measured the strength of association between systolic and diastolic BP various components at different timepoints with unfavorable 3 month-outcome, defined as death or moderate-to-severe disability at 3 months (mRS of 4-6), after adjustment for known confounders. We also dichotomized BP values obtained at 24 h at different thresholds to better define an optimal treatment target. The association of BP with hematoma expansion (HE) was also analyzed.

RESULTS

A total of 384 patients were included. Higher BP at 24 hours was associated with unfavorable outcome for systolic BP (OR 1.16, 95% C.I. 1.07-1.25), pulse pressure (OR 1.13, 95% C.I. 1.03-1.24), and diastolic BP (OR 1.11, 95% C.I. 1.01-1.23) per 10 mm Hg increment. The association between higher BP at 24 h and unfavorable outcome remained significant down to >140 mm Hg. Elevated systolic BP at 24 h was also associated with HE (OR 1.11, 95% C.I. 1.02-1.21 per 10 mm Hg increment).

CONCLUSION

Elevated BP after ICH at 24 h is associated with poor outcome. Our results support the practice of targeting a systolic BP of 140 mm Hg.

Randomized Controlled Trials on Intracerebral Hemorrhage: A Cross Sectional Retrospective Analysis of CONSORT Item Adherence

Object: Intracranial hemorrhage (ICH) is the second most common cause of stroke but still there is little consolidated knowledge about the optimal treatment strategies (e.g., the benefit of surgical evacuation). We evaluated the current randomized controlled trials (RCTs) on primary ICH (01.2013–03.2017) according to their fulfillment of the CONSORT statement's criteria (published in 2010) –as a marker of transparency and quality of study planning and realization.

Methods: A Pubmed and a Cochrane database (including clinicaltrials.gov) search was carried out (01.2014–3.2017, respectively 01.2013–12.2013). Abstracts were screened for inclusion. Eligible full text manuscripts were assessed for the implementation of the CONSORT criteria. Citation frequencies and impact factors of the journals were related to ratio of CONSORT criteria fulfillment. Further, the risk of bias according to the Risk of bias tool 2 (RoB 2) was assessed.

Results: Overall 3097 abstracts were screened for inclusion; 39 studies were suitable for final analysis. A mean fulfillment ratio of 51% (±28%) was found. A high correlation between impact factor and adherence to CONSORT criteria was shown (r = 0.7664; p < 0.0001). Citation frequency per year was related to ratio of CONSORT item fulfillment (r = 0.6747; p < 0.0001) and to the impact factor of the publishing journal (r = 0.7310; p < 0.0001). Of note, the items 10 (randomization: implementation) and 21 (generalizability) showed particularly high rates of non-fulfillment (87 and 85%). The majority of studies (95%) complied with item 2b (specific objectives or hypotheses), but strikingly objectives were mostly described vaguely. Other essential criteria such as sample size determination, definition of outcome parameters, and participant flow were only fulfilled weakly (51, 54, and 39%).

Conclusions: Over 20 years after its inception there is still weak adherence to the CONSORT statement. As a consequence, conclusions are hampered by inadequate planning and/or reporting. Particularly with respect to pathologies as ICH lacking clear, evidence-based guidelines adherence to the CONSORT statement might improve research quality in order to define valuable treatment strategies.

A Narrative Review of Cardiovascular Abnormalities After Spontaneous Intracerebral Hemorrhage

BACKGROUND

The recommended cardiac workup of patients with spontaneous intracerebral hemorrhage (ICH) includes an electrocardiogram (ECG) and cardiac troponin. However, abnormalities in other cardiovascular domains may occur. We reviewed the literature to examine the spectrum of observed cardiovascular abnormalities in patients with ICH.

METHODS

A narrative review of cardiovascular abnormalities in ECG, cardiac biomarkers, echocardiogram, and hemodynamic domains was conducted on patients with ICH.

RESULTS

We searched PubMed for articles using MeSH Terms "heart," "cardiac," hypertension," "hypotension," "blood pressure," "electro," "echocardio," "troponin," "beta natriuretic peptide," "adverse events," "arrhythmi," "donor," "ICH," "intracerebral hemorrhage." Using Covidence software, 670 articles were screened for title and abstracts, 482 articles for full-text review, and 310 extracted. A total of 161 articles met inclusion and exclusion criteria, and, included in the manuscript. Cardiovascular abnormalities reported after ICH include electrocardiographic abnormalities (56% to 81%) in form of prolonged QT interval (19% to 67%), and ST-T changes (19% to 41%), elevation in cardiac troponin (>0.04 ng/mL), and beta-natriuretic peptide (BNP) (>156.6 pg/mL, up to 78%), echocardiographic abnormalities in form of regional wall motion abnormalities (14%) and reduced ejection fraction. Location and volume of ICH affect the prevalence of cardiovascular abnormalities. Prolonged QT interval, elevated troponin-I, and BNP associated with increased in-hospital mortality after ICH. Blood pressure control after ICH aims to preserve cerebral perfusion pressure and maintain systolic blood pressure between 140 and 179 mm Hg, and avoid intensive blood pressure reduction (110 to 140 mm Hg). The recipients of ICH donor hearts especially those with reduced ejection fraction experience increased early mortality and graft rejection.

CONCLUSIONS

Various cardiovascular abnormalities are common after spontaneous ICH. The workup of patients with spontaneous ICH should involve 12-lead ECG, cardiac troponin-I, as well as BNP, and echocardiogram to evaluate for heart failure. Blood pressure control with preservation of cerebral perfusion pressure is a cornerstone of hemodynamic management after ICH. The perioperative implications of hemodynamic perturbations after ICH warrant urgent further examination.

Intracranial hemorrhage in patients taking oral anticoagulants. Current possibilities for therapy

The paper reviews an update on the possibilities of providing care for patients with spontaneous non-traumatic intracranial hemorrhage (ICH) developing in patients with atrial fibrillation who use oral anticoagulants. The incidence of ICH is shown to be considerably lower when nonvitamin K-dependent anticoagulants (NOACs) are used, but the hematoma evolution scenarios do not differ between the groups of patients receiving vitamin K antagonists or NOACs. The results of studies assessing hypertension therapy in patients with ICH are compared. The possibilities of using various reversal agents for various oral anticoagulants are also discussed. Since one of the main problems associated with increased mortality and severe disabilities is the progression rate of ICH, the possibility of using a specific antagonist can determine the choice of an anticoagulant for the primary prevention of ischemic stroke in a patient with atrial fibrillation.

An update on neurocritical care for intracerebral hemorrhage

Introduction: Intracerebral hemorrhage remains one of the leading causes of death and disability worldwide with few established interventions that improve neurologic outcome. Research dedicated to better understanding and treating hemorrhagic strokes has multiplied in the past decade. Areas Covered: This review aims to discuss the current landscape of management of intracerebral hemorrhage in a critical care setting and provide updates regarding developments in therapeutic interventions and targets. PubMed was utilized to review recent literature, with a focus on large trials and meta-analyses, which have shaped current practice. Published committee guidelines were also included. A focus was placed on research published after 2015 in an effort to supplement previous reviews included in this publication. Expert Opinion: Literature pertaining to ICH management has allowed for a greater understanding of ineffective strategies as opposed to those of benefit. Despite this, mortality has improved worldwide, which may be the result of growing research efforts. Areas of future research that will impact mortality and improve neurologic outcomes include prevention of hematoma expansion, optimization of blood pressure targets, effective coagulopathy reversal, and minimally invasive surgical techniques to reduce hematoma burden.

Advancements in Managing Intracerebral Hemorrhage: Transition from Nihilism to Optimism

There have been significant advancements in the management of intracerebral hemorrhage (ICH) stemming from new knowledge on its pathogenesis. Major clinical trials, such as Surgical Trial in Lobar Intracerebral Hemorrhage (STICH I and II), have shown only a small, albeit clinically relevant, advantage of surgical interventions in specific subsets of patients suffering from ICH. Currently, the aim is to use a minimally invasive and safe trajectory in removing significant brain hematomas with the aid of neuro-endoscopy or precise guidance through neuro-navigation, thereby avoiding a collateral damage to the surrounding normal brain tissue. A fundamental rational to such approach is to safely remove hematoma, preventing the ongoing mass effect resulting in brain herniation, and to minimize deleterious effects of iron released from hematoma to brain cells. The clot lysis process is facilitated with the adjunctive use of recombinant tissue plasminogen activator and sonolysis. Revised recommendations for the management of ICH focus on a holistic approach, with special emphasis on early patient mobilization and graded rehabilitative process. There has been a paradigm shift in the management algorithm, putting emphasis on early and safe removal of brain hematoma and then focusing on the improvement of patients' quality of life. We have made significant progress in transition from nihilism toward optimism, based on evidence-based management of such a severe global health scourge as intracranial hemorrhage.

Safety and efficacy of applying sufficient analgesia combined with a minimal sedation program as an early antihypertensive treatment for spontaneous intracerebral hemorrhage: a randomized controlled trial

Background

Spontaneous intracerebral hemorrhage (ICH) is a serious threat to human health. Although early blood pressure (BP) elevation is closely associated with a poor prognosis, the optimal antihypertensive regimen for acute-phase ICH remains controversial. In ICH, pain, sleep deprivation, and stress are usually the main causes of dramatic BP increases. While traditional antihypertensive treatment resolves the increased BP, it does not address the root cause of the disease. Remifentanil relieves pain and, when combined with dexmedetomidine’s antisympathetic action, can restore elevated BP to normal levels. Here, we seek to validate the efficacy and safety of applying sufficient analgesia in combination with a minimal sedation program versus antihypertensive drug therapy for the early and rapid stabilization of BP in ICH patients.

Methods/design

We are conducting a multicenter, prospective, randomized controlled, single-blinded, superiority clinical trial across 15 hospitals. We will enroll 354 subjects in mainland China, and all subjects will be randomized into experimental and control groups in which they will be given remifentanil combined with dexmedetomidine or antihypertensive drugs (urapidil, nicardipine, and labetalol). The primary endpoint will be the systolic BP control rate within 1 h of treatment initiation, and the efficacy and safety of the antihypertensive regimens will be compared between the two groups. Secondary endpoints include the incidence rate of early hemorrhage growth, neurological function, duration of intensive care unit (ICU) stay, and staff satisfaction with the treatment process.

Discussion

We hypothesize that applying sufficient analgesia in combination with minimal sedation will act as an effective and safe antihypertensive strategy in ICH and that this treatment strategy could, therefore, be widely used as an ICH acute-phase therapy.

Trial registration

ClinicalTrials.gov, ID: NCT03207100. Registered on 22 July 2017.

Electronic supplementary material

The online version of this article (10.1186/s13063-018-2943-6) contains supplementary material, which is available to authorized users.

Evolution of blood pressure management in acute intracerebral hemorrhage

Intracerebral hemorrhage (ICH) remains a prevalent and severe cause of death and disability worldwide. Control of the hypertensive response in acute ICH has been a mainstay of ICH management, yet the optimal approaches and the yield of recommended strategies have been difficult to establish despite a large body of literature. Over the years, theoretical and observed risks and benefits of intensive blood pressure reduction in ICH have been studied in the form of animal models, radiographic studies, and two recent large, randomized patient trials. In this article, we review the historical and developing data and discuss remaining questions surrounding blood pressure management in acute ICH.

The critical care management of spontaneous intracranial hemorrhage: a contemporary review

Spontaneous intracerebral hemorrhage (ICH), defined as nontraumatic bleeding into the brain parenchyma, is the second most common subtype of stroke, with 5.3 million cases and over 3 million deaths reported worldwide in 2010. Case fatality is extremely high (reaching approximately 60 % at 1 year post event). Only 20 % of patients who survive are independent within 6 months. Factors such as chronic hypertension, cerebral amyloid angiopathy, and anticoagulation are commonly associated with ICH. Chronic arterial hypertension represents the major risk factor for bleeding. The incidence of hypertension-related ICH is decreasing in some regions due to improvements in the treatment of chronic hypertension. Anticoagulant-related ICH (vitamin K antagonists and the newer oral anticoagulant drugs) represents an increasing cause of ICH, currently accounting for more than 15 % of all cases. Although questions regarding the optimal medical and surgical management of ICH still remain, recent clinical trials examining hemostatic therapy, blood pressure control, and hematoma evacuation have advanced our understanding of ICH management. Timely and aggressive management in the acute phase may mitigate secondary brain injury. The initial management should include: initial medical stabilization; rapid, accurate neuroimaging to establish the diagnosis and elucidate an etiology; standardized neurologic assessment to determine baseline severity; prevention of hematoma expansion (blood pressure management and reversal of coagulopathy); consideration of early surgical intervention; and prevention of secondary brain injury. This review aims to provide a clinical approach for the practicing clinician.

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.

Capillary transit time heterogeneity and flow-metabolism coupling after traumatic brain injury

Most patients who die after traumatic brain injury (TBI) show evidence of ischemic brain damage. Nevertheless, it has proven difficult to demonstrate cerebral ischemia in TBI patients. After TBI, both global and localized changes in cerebral blood flow (CBF) are observed, depending on the extent of diffuse brain swelling and the size and location of contusions and hematoma. These changes vary considerably over time, with most TBI patients showing reduced CBF during the first 12 hours after injury, then hyperperfusion, and in some patients vasospasms before CBF eventually normalizes. This apparent neurovascular uncoupling has been ascribed to mitochondrial dysfunction, hindered oxygen diffusion into tissue, or microthrombosis. Capillary compression by astrocytic endfeet swelling is observed in biopsies acquired from TBI patients. In animal models, elevated intracranial pressure compresses capillaries, causing redistribution of capillary flows into patterns argued to cause functional shunting of oxygenated blood through the capillary bed. We used a biophysical model of oxygen transport in tissue to examine how capillary flow disturbances may contribute to the profound changes in CBF after TBI. The analysis suggests that elevated capillary transit time heterogeneity can cause critical reductions in oxygen availability in the absence of 'classic' ischemia. We discuss diagnostic and therapeutic consequences of these predictions.

Vascular disruption and blood-brain barrier dysfunction in intracerebral hemorrhage

This article reviews current knowledge of the mechanisms underlying the initial hemorrhage and secondary blood-brain barrier (BBB) dysfunction in primary spontaneous intracerebral hemorrhage (ICH) in adults. Multiple etiologies are associated with ICH, for example, hypertension, Alzheimer's disease, vascular malformations and coagulopathies (genetic or drug-induced). After the initial bleed, there can be continued bleeding over the first 24 hours, so-called hematoma expansion, which is associated with adverse outcomes. A number of clinical trials are focused on trying to limit such expansion. Significant progress has been made on the causes of BBB dysfunction after ICH at the molecular and cell signaling level. Blood components (e.g. thrombin, hemoglobin, iron) and the inflammatory response to those components play a large role in ICH-induced BBB dysfunction. There are current clinical trials of minimally invasive hematoma removal and iron chelation which may limit such dysfunction. Understanding the mechanisms underlying the initial hemorrhage and secondary BBB dysfunction in ICH is vital for developing methods to prevent and treat this devastating form of stroke.

The role of the microcirculation in delayed cerebral ischemia and chronic degenerative changes after subarachnoid hemorrhage

The mortality after aneurysmal subarachnoid hemorrhage (SAH) is 50%, and most survivors suffer severe functional and cognitive deficits. Half of SAH patients deteriorate 5 to 14 days after the initial bleeding, so-called delayed cerebral ischemia (DCI). Although often attributed to vasospasms, DCI may develop in the absence of angiographic vasospasms, and therapeutic reversal of angiographic vasospasms fails to improve patient outcome. The etiology of chronic neurodegenerative changes after SAH remains poorly understood. Brain oxygenation depends on both cerebral blood flow (CBF) and its microscopic distribution, the so-called capillary transit time heterogeneity (CTH). In theory, increased CTH can therefore lead to tissue hypoxia in the absence of severe CBF reductions, whereas reductions in CBF, paradoxically, improve brain oxygenation if CTH is critically elevated. We review potential sources of elevated CTH after SAH. Pericyte constrictions in relation to the initial ischemic episode and subsequent oxidative stress, nitric oxide depletion during the pericapillary clearance of oxyhemoglobin, vasogenic edema, leukocytosis, and astrocytic endfeet swelling are identified as potential sources of elevated CTH, and hence of metabolic derangement, after SAH. Irreversible changes in capillary morphology and function are predicted to contribute to long-term relative tissue hypoxia, inflammation, and neurodegeneration. We discuss diagnostic and therapeutic implications of these predictions.