Guidelines for the management of patients with acute ischemic stroke. A statement for healthcare professionals from a special writing group of the Stroke Council, American Heart Association

Proper Indication of Decompressive Craniectomy for the Patients with Massive Brain Edema after Intra-arterial Thrombectomy

OBJECTIVE

Numerous studies have indicated that early decompressive craniectomy (DC) for patients with major infarction can be life-saving and enhance neurological outcomes. However, most of these studies were conducted by neurologists before the advent of intra-arterial thrombectomy (IA-Tx). This study aims to determine whether neurological status significantly impacts the final clinical outcome of patients who underwent DC following IA-Tx in major infarction.

METHODS

This analysis included 67 patients with major anterior circulation major infarction who underwent DC after IA-Tx, with or without intravenous tissue plasminogen activator. We retrospectively reviewed the medical records, radiological findings, and compared the neurological outcomes based on the "surgical time window" and neurological status at the time of surgery.

RESULTS

For patients treated with DC following IA-Tx, a Glasgow coma scale (GCS) score of 7 was the lowest score correlated with a favorable outcome (p=0.013). Favorable outcomes were significantly associated with successful recanalization after IA-Tx (p=0.001) and perfusion/diffusion (P/D)-mismatch evident on magnetic resonance imaging performed immediately prior to IA-Tx (p=0.007). However, the surgical time window (within 36 hours, p=0.389; within 48 hours, p=0.283) did not correlate with neurological outcomes.

CONCLUSION

To date, early DC surgery after major infarction is crucial for patient outcomes. However, this study suggests that the indication for DC following IA-Tx should include neurological status (GCS ≤7), as some patients treated with early DC without considering the neurological status may undergo unnecessary surgery. Recanalization of the occluded vessel and P/D-mismatch are important for long-term neurological outcomes.

Current U.S. Guideline-Based Management Strategies for Special Clinical Situations Involving Hypertensive Crises: A Narrative Review of the Literature

Hypertensive crises, although somewhat rare in hypertensive patients, might become an increasingly relevant issue in the future as the number of adults living with hypertension in the United States increases. Many of the current U.S. clinical guidelines for the treatment and management of a variety of medical conditions do not factor hypertensive crises into their recommendations or only consider them in a limited fashion in the context of other medical conditions. This review article summarizes the definitions of hypertensive crises/urgent hypertension/emergent hypertension, the epidemiological profile and outcomes of patients, current U.S. clinical guidelines' recommendations for the general treatment of hypertensive crises, and current U.S. clinical guidelines' recommendations for the treatment of acute kidney injuries, acute ischemic stroke, aortic dissection, and acute heart failure in relation to hypertensive crises. All physicians who manage hypertensive patients, but particularly physicians who work in intensive care units, emergency departments and in U.S. hospitals, should review hypertensive crises guidelines and relevant treatments, and understand current recommendations.

Indications for Mechanical Thrombectomy for Acute Ischemic Stroke: Current Guidelines and Beyond

PURPOSE OF THE REVIEW

This article reviews recent breakthroughs in the treatment of acute ischemic stroke, mainly focusing on the evolution of endovascular thrombectomy, its impact on guidelines, and the need for and implications of next-generation randomized controlled trials.

RECENT FINDINGS

Endovascular thrombectomy is a powerful tool to treat large vessel occlusion strokes and multiple trials over the past 5 years have established its safety and efficacy in the treatment of anterior circulation large vessel occlusion strokes up to 24 hours from stroke onset.

SUMMARY

In 2015, multiple landmark trials (MR CLEAN, ESCAPE, SWIFT PRIME, REVASCAT, and EXTEND IA) established the superiority of endovascular thrombectomy over medical management for the treatment of anterior circulation large vessel occlusion strokes. Endovascular thrombectomy has a strong treatment effect with a number needed to treat ranging from 3 to 10. These trials selected patients based on occlusion location (proximal anterior occlusion: internal carotid or middle cerebral artery), time from stroke onset (early window: up to 6-12 hours), and acceptable infarct burden (Alberta Stroke Program Early CT Score [ASPECTS] ≥6 or infarct volume <50 mL). In 2017, the DAWN and DEFUSE-3 trials successfully extended the time window up to 24 hours in appropriately selected patients. Societal and national thrombectomy guidelines have incorporated these findings and offer Class 1A recommendation to a subset of well-selected patients. Thrombectomy ineligible stroke subpopulations are being studied in ongoing randomized controlled trials. These trials, built on encouraging data from pooled analysis of early trials (HERMES collaboration) and emerging retrospective data, are studying large vessel occlusion strokes with mild deficits (National Institutes of Health Stroke Scale <6) and large infarct burden (core volume >70 mL).

The Story of Intracerebral Hemorrhage: From Recalcitrant to Treatable Disease

This invited special report is based on an award presentation at the World Stroke Organization/European Stroke Organization Conference in November of 2020 outlining progress in the acute management of intracerebral hemorrhage (ICH) over the past 35 years. ICH is the second most common and the deadliest type of stroke for which there is no scientifically proven medical or surgical treatment. Prospective studies from the 1990s onward have demonstrated that most growth of spontaneous ICH occurs within the first 2 to 3 hours and that growth of ICH and resulting volumes of ICH and intraventricular hemorrhage are modifiable factors that can improve outcome. Trials focusing on early treatment of elevated blood pressure have suggested a target systolic blood pressure of 140 mm Hg, but none of the trials were positive by their primary end point. Hemostatic agents to decrease bleeding in spontaneous ICH have included desmopressin, tranexamic acid, and rFVIIa (recombinant factor VIIa) without clear benefit, and platelet infusions which were associated with harm. Hemostatic agents delivered within the first several hours have the greatest impact on growth of ICH and potentially on outcome. No large Phase III surgical ICH trial has been positive by primary end point, but pooled analyses suggest that earlier ICH removal is more likely to be beneficial. Recent trials emphasize maximization of clot removal and minimizing brain injury from the surgical approach. The future of ICH therapy must focus on delivery of medical and surgical therapies as soon as possible if we are to improve outcomes.

Blood Pressure Management in Acute Stroke: Comparison of Current Guidelines with Prescribing Patterns

Objective:

Current recommendations for treating elevated blood pressure (BP) in the acute stroke are based largely on expert opinion and vary with regard to treatment thresholds and choice of antihypertensive agents. In this study we investigate the influence of these recommendations by comparing the management of hypertension in acute stroke at a tertiary care hospital with current guidelines.

Method:

Retrospective chart review of patients admitted with acute stroke at The Ottawa Hospital-General Campus over six consecutive months. The use of antihypertensive medications (type, dose, routes of administration, BP recordings) in the first seven days after admission was noted.

Results:

Transdermal nitroglycerin paste was the most commonly used antihypertensive agent. In contrast to the 15% reduction in BP over 24 hours recommended for lowering BP in hypertensive patients with ischemic stroke, nitroglycerin caused a >15% reduction of BPover the first 24 hours on 60% of the occasions used. Furthermore, despite concerns about sublingual nifedipine, this was the second most commonly prescribed agent. Surprisingly, the mean time to first BP measurement following initiation of antihypertensive therapy was 117 ± 43 minutes in ischemic stroke and 88 ± 89 minutes in hemorrhagic strokes.

Conclusions:

The current guidelines for management of acute poststroke hypertension appear to have little influence on prescribing patterns, leading to considerable variations in practice. Such variations, likely due to uncertainty caused by lack of evidence from randomised controlled trials, are intolerable as patients maybe submitted to nonstandardised, potentially harmful care such as inappropriate choice of antihypertensives and inadequate BP monitoring as observed in this study.

Comparative effects of robotic-assisted gait training combined with conventional physical therapy on paretic hip joint stiffness and kinematics between subacute and chronic hemiparetic stroke

BACKGROUND

Robotic-assisted gait training (RAGT) has been proposed as a novel, promising intervention paradigm to improve gait function in subacute or chronic stroke neurorehabilitation. However, the benefits of RAGT combined with conventional physical therapy for gait recovery in patients with subacute and chronic hemiparetic stroke remain unclear.

OBJECTIVES

The aim of the present study was to compare the effect of RAGT combine with conventional physical therapy on hip joint kinetics, kinematics, and clinical function characteristics between subacute and chronic hemiparetic stroke.

METHODS

Seventeen patients with hemiparetic stroke (nine subacute and eight chronic patients) performed progressive RAGT (session 1, 40 min) combined with conventional physical therapy (session 1, 40 min) 5 days per week, for an average of 86 sessions over 8 weeks. The clinical outcomes included the Functional Ambulation Category (FAC), modified Rankin scale (mRS), Korean version of the modified Barthel index (K-MBI), and modified Ashworth scale, in addition to hip joint kinetics and kinematics before and after intervention.

RESULTS

The mean change in active torque, resistive torque, and stiffness in the paretic hip joint did not differ significantly between the two groups. However, Cohen's effect size suggested a moderate difference between the groups in the hip flexion phase (d = 0.58, d = 0.70, and d = 0.70). The mean change in maximal hip flexion kinematics in the chronic group was significantly greater than that in the subacute group (p = 0.04, d = -0.70). The mean change in the clinical function test results between the groups was not statistically significant. However, both groups showed significantly improved FAC, mRS, and K-MBI scores.

CONCLUSIONS

RAGT combine with conventional physical therapy may be useful when selecting therapeutic interventions to improve the active torque, resistive torque, and stiffness in the paretic hip flexion phase in patients with chronic hemiparetic stroke who reached a plateau in the maximum locomotor recovery after conventional locomotor training.

Acute Ischaemic Stroke: Management, Recent Advances and Controversies

Acute ischaemic stroke is a major cause of death and disability. It may become an enormous burden to the patients themselves, their families as well as the health care systems. Patients at risk of airway, breathing and circulatory compromise should receive prompt resuscitation. Vital parameters and neurological status should be closely monitored. Attentions to blood pressure, temperature and sugar profile are important. The significance of early and correct diagnosis and subsequent treatment cannot be over-emphasised. There have been tremendous recent advances in different treatment modalities in acute stroke management. Various recanalisation modalities include intravenous and/or intra-arterial thrombolysis, acute defibrinogenation, anti-platelet treatment and anticoagulation. Carotid endarterectomy and endovascular strategies are recommended in selected patients. Advanced neuro-imaging techniques and neuroprotectants are being evaluated. Multidisciplinary stroke teams have been shown to improve patient survival and functional outcome. Pre-defined algorithms and protocols should be in place to expedite smooth and effective delivery of stroke service. Future directions should be aimed at exploring safer recanalisation modalities and extending the limit of the current 3-hour treatment window for thrombolysis.

Endocarditis caused by anaerobic bacteria

BACKGROUND

Infective endocarditis (IE) caused by anaerobic bacteria is a rare and poorly characterized disease. Most data reported in the literature are from case reports [1-3]. Therefore, we assessed the situation of anaerobic IE (AIE) in Spain using the database of the Spanish Collaboration on Endocarditis (GAMES).

METHODS

We performed a prospective study from 2008 to 2016 in 26 Spanish centers. We included 2491 consecutive cases of definite IE (Duke criteria).

RESULTS

Anaerobic bacteria caused 22 cases (0.9%) of definite IE. Median age was 66 years (IQR, 56-73), and 19 (86.4%) patients were men. Most patients (14 [63.6%]) had prosthetic valve IE and all episodes were left-sided: aortic valves, 12 (54.5%); and mitral valves, 8 (36.4%). The most common pathogens were Propionibacterium acnes (14 [63.6%]), Lactobacillus spp (3 [13.63%]), and Clostridium spp. (2 [9.0%]), and the infection was mainly odontogenic. Fifteen of the 22 patients (68.2%) underwent cardiac surgery. Mortality was 18.2% during admission and 5.5% after 1 year of follow-up. When patients with AIE were compared with the rest of the cohort, we found that although those with AIE had a similar age and Charlson comorbidity index, they were more likely to have community-acquired IE (86.4% vs. 60.9%, p = 0.01), have undergone cardiac surgery (68.2% vs 48.7% p = 0.06), and have had lower mortality rates during admission (18.2% vs. 27.3%).

CONCLUSION

IE due to anaerobic bacteria is an uncommon disease that affects mainly prosthetic valves and frequently requires surgery. Otherwise, there are no major differences between AIE and IE caused by other microorganisms.

The effects of position on oxygen saturation in acute stroke: a systematic review

Objective: To investigate the effect of body position on oxygen saturation in the acute stages post stroke.

Design: Systematic review.

Methods: Databases: PREMEDLINE and MEDLINE, Psychinfo, EMBASE, CINAHL, PEDro, all EBM Reviews and Scottish Intercollegiate Guidelines Network (SIGN). Keywords: combinations of cerebrovascular accident/stroke/hemiplegia/ cerbrovascular disorders and position or posture or sitting or standing/lying/supine/ side lying, with oxygen saturation/oxygen levels/blood gas analysis/hypoxia/sleep apnea syndrome/obstructive sleep disorder/Cheyne Stokes breathing. Limits: English language, human, adults and clinical trials. The quality of relevant papers was independently reviewed using criteria based on the SIGN guidelines for randomized controlled trials and methods described by Rywdik et al.

Results: There were four relevant studies involving 183 patients: three high quality and one poor quality. Heterogeneity in the testing positions, selection criteria, outcome measures and analysis methods prevented meta-analysis. There was strong evidence that body position did not affect oxygen saturation in acute stroke patients without relevant (respiratory) co-morbidities. There was limited evidence that sitting in a chair had a beneficial effect and lying positions had a deleterious effect on oxygen saturation in acute stroke patients with respiratory co-morbidities.

Conclusions: Acute stroke patients without respiratory co-morbidities can adopt any body position, people with respiratory co-morbidities should be positioned as upright as possible.

Development of regional stroke programs

The organization of stroke care has undergone a dramatic evolution in the USA over the last two decades. Beginning with the recommendation for Primary Stroke Centers (PSCs) in 1994, there has been a concerted effort by physicians, the American Heart Association/American Stroke Association (AHA/ASA), National Institutes of Health (NIH), and state legislatures to advance an evidence-based system of care with several tiers of stroke centers. At the apex of this structure are Regional Stroke Centers (RSCs), which do not have official recognition like PSCs and Comprehensive Stroke Centers (CSCs), but their existence as a hub for the many disparate spokes of stroke care in their region is increasingly necessary. Observational evidence suggests that this approach is improving the delivery of stroke care and reducing costs in the USA. Similar efforts are being made in Europe and Asia with encouraging results. The RSC model has the potential to lead to more uniform evidence-based stroke medicine, but many challenges exist.

Effectiveness of regionalized systems for stroke and myocardial infarction

BACKGROUND

Acute ischemic stroke (AIS) and ST-segment elevation myocardial infarction (STEMI) are ischemic emergencies. Guidelines recommend care delivery within formally regionalized systems of care at designated centers, with bypass of nearby centers of lesser or no designation. We review the evidence of the effectiveness of regionalized systems in AIS and STEMI.

METHODS

Literature was searched using terms corresponding to designation of AIS and STEMI systems and from 2010 to the present. Inclusion criteria included report of an outcome on any dependent variable mentioned in the rationale for regionalization in the guidelines and an independent variable comparing care to a non- or pre-regionalized system. Designation was defined in the AIS case as certification by the Joint Commission as either a primary (PSC) or comprehensive (CSC) stroke center. In the STEMI case, the search was conducted linking "regionalization" and "myocardial infarction" or citation as a model system by any American Heart Association statement.

RESULTS

For AIS, 17 publications met these criteria and were selected for review. In the STEMI case, four publications met these criteria; the search was therefore expanded by relaxing the criteria to include any historical or anecdotal comparison to a pre- or nonregionalized state. The final yield was nine papers from six systems.

CONCLUSION

Although regionalized care results in enhanced process and reduced unadjusted rates of disparity in access and adverse outcomes, these differences tend to become nonsignificant when adjusted for delayed presentation and hospital arrival by means other than emergency medical services. The benefits of regionalized care occur along with a temporal trend of improvement due to uptake of quality initiatives and guideline recommendations by all systems regardless of designation. Further research is justified with a randomized registry or cluster randomized design to support or refute recommendations that regionalization should be the standard of care.

Current Epidemiology and Outcome of Infective Endocarditis: A Multicenter, Prospective, Cohort Study

The aim of the study was to describe the epidemiologic and clinical characteristics and identify the risk factors of short-term and 1-year mortality in a recent cohort of patients with infective endocarditis (IE).From January 2008, multidisciplinary teams have prospectively collected all consecutive cases of IE, diagnosed according to the Duke criteria, in 25 Spanish hospitals.Overall, 1804 patients were diagnosed. The median age was 69 years (interquartile range, 55-77), 68.0% were men, and 37.1% of the cases were nosocomial or health care-related IE. Gram-positive microorganisms accounted for 79.3% of the episodes, followed by Gram-negative (5.2%), fungi (2.4%), anaerobes (0.9%), polymicrobial infections (1.9%), and unknown etiology (9.1%). Heart surgery was performed in 44.2%, and in-hospital mortality was 28.8%. Risk factors for in-hospital mortality were age, previous heart surgery, cerebrovascular disease, atrial fibrillation, Staphylococcus or Candida etiology, intracardiac complications, heart failure, and septic shock. The 1-year independent risk factors for mortality were age (odds ratio [OR], 1.02), neoplasia (OR, 2.46), renal insufficiency (OR, 1.59), and heart failure (OR, 4.42). Surgery was an independent protective factor for 1-year mortality (OR, 0.44).IE remains a severe disease with a high rate of in-hospital (28.9%) and 1-year mortality (11.2%). Surgery was the only intervention that significantly reduced 1-year mortality.

Electroencephalography as a post-stroke assessment method: An updated review

Given that stroke is currently a serious problem in the population, employing more reliable and objective techniques for determining diagnosis and prognosis is necessary in order to enable effective clinical decision-making. EEG is a simple, low-cost, non-invasive tool that can provide information about the changes occurring in the cerebral cortex during the recovery process after stroke. EEG provides data on the evolution of cortical activation patterns which can be used to establish a prognosis geared toward harnessing each patient's full potential. This strategy can be used to prevent compensation and maladaptive plasticity, redirect treatments, and develop new interventions that will let stroke patients reach their new maximum motor levels.

Acute supratentorial ischemic stroke: when surgery is mandatory

Acute occlusion of middle cerebral artery (MCA) leads to severe brain swelling and to a malignant, often fatal syndrome. The authors summarize the current knowledge about such a condition and review the main surgical issues involved. Decompressive hemicraniectomy keeps being a valid option in accurately selected patients.

Vagus nerve stimulation during rehabilitative training improves forelimb strength following ischemic stroke

Upper limb impairment is a common debilitating consequence of ischemic stroke. Physical rehabilitation after stroke enhances neuroplasticity and improves limb function, but does not typically restore normal movement. We have recently developed a novel method that uses vagus nerve stimulation (VNS) paired with forelimb movements to drive specific, long-lasting map plasticity in rat primary motor cortex. Here we report that VNS paired with rehabilitative training can enhance recovery of forelimb force generation following infarction of primary motor cortex in rats. Quantitative measures of forelimb function returned to pre-lesion levels when VNS was delivered during rehab training. Intensive rehab training without VNS failed to restore function back to pre-lesion levels. Animals that received VNS during rehab improved twice as much as rats that received the same rehabilitation without VNS. VNS delivered during physical rehabilitation represents a novel method that may provide long-lasting benefits towards stroke recovery.

Implementing clinical guidelines in stroke: a qualitative study of perceived facilitators and barriers

BACKGROUND

Clinical guidelines are frequently used as a mechanism for implementing evidence-based practice. However research indicates that health professionals vary in the extent to which they adhere to these guidelines. This study aimed to study the perceptions of stakeholders and health professionals on the facilitators and barriers to implementing national stroke guidelines in Ireland.

METHODS

Qualitative interviews using focus groups were conducted with stakeholders (n=3) and multidisciplinary team members from hospitals involved in stroke care (n=7). All focus group interviews were semi-structured, using open-ended questions. Data was managed and analysed using NVivo 9 software.

RESULTS

The main themes to emerge from the focus groups with stakeholders and hospital multidisciplinary teams were very similar in terms of topics discussed. These were resources, national stroke guidelines as a tool for change, characteristics of national stroke guidelines, advocacy at local level and community stroke care challenges. Facilitators perceived by stakeholders and health professionals included having dedicated resources, user-friendly guidelines relevant at local level and having supportive advocates on the ground. Barriers were inadequate resources, poor guideline characteristics and insufficient training and education.

CONCLUSIONS

This study highlights health professionals' perspectives regarding many key concepts which may affect the implementation of stroke care guidelines. The introduction of stroke clinical guidelines at a national level is not sufficient to improve health care quality as they should be incorporated in a quality assurance cycle with education programmes and feedback from surveys of clinical practice.

Bio-Repository of DNA in stroke (BRAINS): a study protocol

Background

Stroke is one of the commonest causes of mortality in the world and anticipated to be an increasing burden to the developing world. Stroke has a genetic basis and identifying those genes may not only help us define the mechanisms that cause stroke but also identify novel therapeutic targets. However, large scale highly phenotyped DNA repositories are required in order for this to be achieved.

Methods

The proposed Bio-Repository of DNA in Stroke (BRAINS) will recruit all subtypes of stroke as well as controls from two different continents, Europe and Asia. Subjects recruited from the UK will include stroke patients of European ancestry as well as British South Asians. Stroke subjects from South Asia will be recruited from India and Sri Lanka. South Asian cases will also have control subjects recruited.

Discussion

We describe a study protocol to establish a large and highly characterized stroke biobank in those of European and South Asian descent. With different ethnic populations being recruited, BRAINS has the ability to compare and contrast genetic risk factors between those of differing ancestral descent as well as those who migrate into different environments.

Use of antithrombotic medications among elderly ischemic stroke patients

BACKGROUND

The use of antithrombotic medications after ischemic stroke is recommended for deep vein thrombosis prophylaxis and secondary stroke prevention. We assessed the rate of receipt of these therapies among eligible ischemic stroke patients age ≥65 years and determined the effects of age and other patient characteristics on treatment.

METHODS AND RESULTS

The analysis included Medicare fee-for-service beneficiaries discharged with ischemic stroke (ICD 433.x1, 434.x1, 436) randomly selected for inclusion in the Medicare Health Care Quality Improvement Program's National Stroke Project 1998 to 1999, 2000 to 2001. Patients discharged from nonacute facilities, transferred, or terminally ill were excluded. Receipt of in-hospital pharmacological deep vein thrombosis prophylaxis, antiplatelet medication, anticoagulants for atrial fibrillation, and antithrombotic medications at discharge were assessed in eligible patients, stratified by age (65 to 74, 75 to 84, and 85+ years). Descriptive models identified characteristics associated with treatment. Among 31 554 patients, 14.9% of those eligible received pharmacological deep vein thrombosis prophylaxis, 83.9% antiplatelet drugs, 82.8% anticoagulants for atrial fibrillation, and 74.2% were discharged on an antithrombotic medication. Rates of treatment decreased with age and were lowest for patients ages 85 years or older. Admission from a skilled nursing facility and functional dependence were associated with lower treatment rates.

CONCLUSIONS

There was substantial underutilization of antithrombotic therapies among elderly ischemic stroke patients, particularly among the very elderly, those admitted from skilled nursing facilities, and patients with functional dependence. The reasons for low use of antithrombotic therapies, including the apparent underutilization of deep vein thrombosis prophylaxis in otherwise eligible patients, require further investigation.

Cerebrovascular disease in dogs and cats

Cerebrovascular disease is defined as any abnormality of the brain resulting from a pathologic process affecting its blood supply. Stroke or cerebrovascular accident (CVA) is the most common clinical manifestation of cerebrovascular disease, and can be broadly divided into ischemic stroke and hemorrhagic stroke. Ischemic stroke results from occlusion of a cerebral blood vessel by a thrombus or embolism, depriving the brain of oxygen and glucose, whereas hemorrhagic stroke results from rupture of a blood vessel wall within the brain parenchyma or subarachnoid space. Previously considered uncommon, CVA is being recognized with greater frequency in veterinary medicine since magnetic resonance imaging has become more readily available. Once the diagnosis of ischemic or hemorrhagic stroke is confirmed, potential underlying causes should be sought after and treated accordingly.

Heterogeneous vancomycin-intermediate susceptibility phenotype in bloodstream methicillin-resistant Staphylococcus aureus isolates from an international cohort of patients with infective endocarditis: prevalence, genotype, and clinical significance

BACKGROUND

The significance of heterogeneous vancomycin-intermediate Staphylococcus aureus (hVISA) is unknown. Using a multinational collection of isolates from methicillin-resistant S. aureus (MRSA) infective endocarditis (IE), we characterized patients with IE with and without hVISA, and we genotyped the infecting strains.

METHODS

MRSA bloodstream isolates from 65 patients with definite IE from 8 countries underwent polymerase chain reaction (PCR) for 31 virulence genes, pulsed-field gel electrophoresis, and multilocus sequence typing. hVISA was defined using population analysis profiling.

RESULTS

Nineteen (29.2%) of 65 MRSA IE isolates exhibited the hVISA phenotype by population analysis profiling. Isolates from Oceania and Europe were more likely to exhibit the hVISA phenotype than isolates from the United States (77.8% and 35.0% vs 13.9%; P < .001). The prevalence of hVISA was higher among isolates with a vancomycin minimum inhibitory concentration of 2 mg/L (P = .026). hVISA-infected patients were more likely to have persistent bacteremia (68.4% vs 37.0%; P = .029) and heart failure (47.4% vs 19.6%; P = .033). Mortality did not differ between hVISA- and non-hVISA-infected patients (42.1% vs 34.8%, P = .586). hVISA and non-hVISA isolates were genotypically similar.

CONCLUSIONS

In these analyses, the hVISA phenotype occurred in more than one-quarter of MRSA IE isolates, was associated with certain IE complications, and varied in frequency by geographic region.

A review of medical treatments of cerebral vasospasm

We review the literature on the established perioperative therapies for cerebral vasospasm (CV) following aneurysmal subarachnoid hemorrhage (aSAH). Despite aSAH treatment advances, CV continues to be a significant source of post-SAH morbidity and mortality. In fact, CV has been correlated with a 7.5- to three-fold increase in mortality in the first 2 weeks after SAH. As new treatment modalities show promise in animal models and early clinical trials, greater efforts are needed to test these new approaches. Few evidence-based indications for the treatment of vasospasm currently exist. Large-scale randomized clinical trials are needed to determine whether therapies such as magnesium, statins, nitric oxide modulators, endothelin antagonists and others will become standard of care in the prevention and/or treatment of CV.

CONTROVERSIES IN THE ENDOVASCULAR MANAGEMENT OF CEREBRAL VASOSPASM AFTER INTRACRANIAL ANEURYSM RUPTURE AND FUTURE DIRECTIONS FOR THERAPEUTIC APPROACHES

CEREBRAL VASOSPASM IS one of the leading causes of morbidity and mortality after aneurysmal subarachnoid hemorrhage. Despite maximal medical therapy, however, up to 15% of patients surviving the ictus of subarachnoid hemorrhage experience stroke or death from vasospasm. For those cases of vasospasm that are refractory to medical treatment, endovascular techniques are frequently used, including balloon angioplasty with or without intra-arterial infusion of vasodilators, combined endovascular modalities, and aortic balloon devices. In this article, we review each of these therapies and their expanding role in the management of this condition. Moving forward, rigorous prospective outcome assessments after endovascular treatment of cerebral vasospasm are necessary to clearly delineate the efficacy and indications for these techniques.

Normoxic ventilatory resuscitation following controlled cortical impact reduces peroxynitrite-mediated protein nitration in the hippocampus

OBJECTIVES

Ventilatory resuscitation with 100% O2 after severe traumatic brain injury (TBI) raises concerns about the increased production of reactive oxygen species (ROS). The product of peroxynitrite-meditated tyrosine residue nitration, 3-nitrotyrosine (3-NT), is a marker for oxidative damage to proteins. The authors hypothesized that posttraumatic resuscitation with hyperoxia (100% fraction of inspired oxygen [FiO2] concentration) results in increased ROS-induced damage to proteins compared with resuscitation using normoxia (21% FiO2 concentration).

METHODS

Male Sprague-Dawley rats underwent controlled cortical impact (CCI) injury and resuscitation with either normoxic or hyperoxic ventilation for 1 hour (5 rats per group). Twenty-four hours after injury, rat hippocampi were evaluated using 3-NT immunostaining. In a second experiment, animals similarly underwent CCI injury and normoxic or hyperoxic ventilation for 1 hour (4 rats per group). One week after injury, neuronal counts were performed after neuronal nuclei immunostaining.

RESULTS

The 3-NT staining was significantly increased in the hippocampi of the hyperoxic group. The normoxic group showed a 51.0% reduction of staining in the CA1 region compared with the hyperoxic group and a 50.8% reduction in the CA3 region (p < 0.05, both regions). There was no significant difference in staining between the injured normoxic group and sham-operated control groups. In the delayed analysis of neuronal survival (neuronal counts), there was no significant difference between the hyperoxic and normoxic groups.

CONCLUSIONS

In this clinically relevant model of TBI, normoxic resuscitation significantly reduced oxidative damage to proteins compared with hyperoxic resuscitation. Neuronal counts showed no benefit from hyperoxic resuscitation. These findings indicate that hyperoxic ventilation in the early stages after severe TBI may exacerbate oxidative damage to proteins.

Intravenous infusion of calcium antagonist, nicardipine, does not increase intracranial pressure: evaluation in a rat model of transient cerebral ischemia and reperfusion

OBJECTIVE AND METHOD

Early use of parenteral antihypertensive drugs is recommended in acute ischemic stroke patients suffering hypertensive emergencies. Calcium antagonist has been widely employed, although there is controversy as to whether calcium antagonist can be administered safely to patients with intracranial hypertension. In a rat model of transient cerebral ischemia and reperfusion, we evaluated the effect of the calcium antagonist, nicardipine, on intracranial pressure (ICP). Using spontaneously hypertensive rats (SHRs), focal cerebral ischemia was induced by an intraluminal thread method. ICP was monitored continuously employing an intraparenchymal catheter. The mean arterial blood pressure (MABP) was reduced by infusing nicardipine intravenously.

RESULTS

Following 6 hours of transient ischemia and reperfusion, MABP was decreased by about 10 or 20% as compared to the baseline MABP with low-dose or high-dose nicardipine administration, respectively. ICP was significantly increased following reperfusion, although it did not increase further with nicardipine infusion.

CONCLUSION

Under conditions where ICP was high following reperfusion, nicardipine reduced blood pressure safely without increasing ICP in rats.

Formula for use of mannitol in patients with intracerebral haemorrhage and high intracranial pressure

BACKGROUND AND OBJECTIVE

Although mannitol has been widely used in hospitals to treat patients with high intracranial pressure (ICP) secondary to intracerebral haemorrhage (ICH), no universal agreement has been reached regarding the optimal dosage of this agent for achieving appropriate intracranial decompression. The aim of this study was to investigate the effects of different mannitol dosages on ICP and the effects of other factors, such as sex, age, haemorrhage location and haematoma volume, on the ICP-lowering effect of mannitol. The data obtained were then used to construct a formula for estimating the total dosage of mannitol required to reduce ICP in individual patients with ICH.

PATIENTS AND METHODS

A total of 72 patients with ICH and elevated ICP monitored in our intensive care unit were included in this study. Patients with ICH who had hypoxaemia (arterial oxygen saturation <90%), severe functional disturbances of the liver or kidney, acidosis or pathological changes in the visual conducting pathway were not included in this study. Each patient received 20% intravenous mannitol 125 mL every 4, 6 or 8 hours per day to treat elevated ICP, with ICP levels being measured before administration of mannitol and at least three times per day during administration of the drug. When the ICP reached a fixed level, the dosage of mannitol was gradually reduced. The total dosage of mannitol used to reduce the ICP from the highest value to the fixed value was calculated. Data on the patients' sex, age, haemorrhage location and haematoma volume were also obtained. Multivariate regression analysis of the results enabled development of a formula for use of mannitol in patients with ICH and elevated ICP.

RESULTS

Use of mannitol significantly decreased ICP in all patients. The effect of mannitol on ICP reduction was dose-dependent during the period of ICP reduction (p < 0.05) but not after the ICP had reached a fixed level; this limited effectiveness of mannitol when its dosage reaches a certain level was termed 'mannitol saturation dosage'. The reduction in ICP with mannitol was not statistically significantly affected by the patient's sex or age, but was significantly correlated with both haemorrhage location and haematoma volume (p < 0.05). The reduction in ICP with mannitol was greater in patients with supratentorial ICH compared with those with infratentorial ICH (p < 0.0001).

CONCLUSION

The total mannitol dosage required for individual patients with ICH and elevated ICP can be calculated by considering the location of the haemorrhage, the volume of the haematoma and the pretreated ICP reading. To this end, the following formula was derived in the study: Total dosage of mannitol (mL of 20% mannitol) = (x + 31.17900 x y - 3.39853 x z - 244.47590)/0.00752, where x = the pretreated ICP (mmH(2)O), y = the haemorrhage location (supratentorial ICH: y = 0, infratentorial ICH: y = 1) and z = the volume of haematoma (mL). Use of this formula in the clinical setting should help reduce the possibility of adverse effects resulting from administration of excessive dosages of mannitol.

Early infection and prognosis after acute stroke: the Copenhagen Stroke Study

BACKGROUND AND PURPOSE

Infection is a frequent complication in the early course of acute stroke and may adversely affect stroke outcome. In the present study, we investigate early infection developing in patients within 3 days of admission to the hospital and its independent relation to recovery and stroke outcome. In addition, we identify predictors for early infections, infection subtypes, and their relation to initial stroke severity.

METHODS

In the community-based Copenhagen Stroke Study, 1,156 unselected patients were examined for early infection. Stroke severity was assessed with the Scandinavian Stroke Scale (SSS) on admission and at discharge. Multiple logistic and linear regression analyses were used to determine independent relations to early infection. Relevant stroke risk factors, admission stroke severity, and body temperature were included in the analysis.

RESULTS

Of the subjects studied, 19.4% developed early infection. In women, 68% of the early infections were urinary tract infections, and in men, 49% of the early infections were pneumonias. Independent predictors of early infection were advanced age (OR per 10 years, 1.24; 95% CI, 1.02-1.64), female gender (OR, 2.0; 95% CI, 1.3-3.0), and decreased SSS score on admission (OR per 10 points, 0.69; 95% CI, 0.62-0.78). The presence of early infection prolonged hospital stay by a mean of 9.3 days (P < .0001) but not death during hospital stay (P = .78), stroke severity at discharge (P = .32), or rate of discharge to nursing home (P = .17).

CONCLUSION

Advanced age, female gender, and increased stroke severity independently predict development of early infection. The present study indicates that early infection does not influence outcome in acute stroke patients per se, but it delays patient discharge from the hospital.

Advances in vasospasm treatment and prevention

Outcome after aSAH depends on several factors, including the severity of the initial event, perioperative medical management, surgical variables, and the incidence of complications. Cerebral vasospasm (CV) is ure to consistently respond to treatment, emphasizing the need for further research into the underlying mechanisms of SAH-induced cerebrovascular dysfunction. To this end, our paper reviews the relevant literature on the main therapies employed for CV after aSAH and discusses possible avenues for future investigations. Current management of this condition consists of maximal medical therapy, including triple H regimen and oral administration of calcium antagonists, followed by endovascular balloon angioplasty and/or injection of vasodilatory agents for refractory cases. As the precise pathophysiology of CV is further elucidated, the development of promising investigational therapies will follow.

The role of surgery in ischemic stroke: decompressive surgery

PURPOSE OF REVIEW

This review gives an integrated view on the current status of decompressive surgery in space-occupying hemispheric brain infarction with a focus on new developments based on the available data of recent clinical trials, also including preliminary data from randomized trials reported at international stroke conferences in 2006.

RECENT FINDINGS

The treatment of ischemic brain infarction with life-threatening space-occupying edema is, because of a lack of prospective studies, one of the major controversial issues within neurocritical care medicine today. Only a few years ago, massive cerebral infarctions were regarded an untreatable disease with fatal outcome. The introduction of decompressive surgery (hemicraniectomy) has completely changed this point of view. Most of the reports, however, are retrospective with low numbers of patients. There are only few prospective trials that suggest a substantial benefit of decompressive surgery to significantly reduce mortality as compared to maximal conservative treatment alone. The control groups in these studies, however, consist of patients with higher age and higher rates of co-morbidities. Also, in most studies information on long-term outcome is insufficient. In 2006 long expected preliminary data from randomized trials of hemicraniectomy have been reported at international stroke conferences. They yield very positive results.

SUMMARY

Decompressive surgery appears to be a promising treatment option for patients with space-occupying hemispheric brain infarction.

Clinical review: Therapy for refractory intracranial hypertension in ischaemic stroke

The treatment of patients with large hemispheric ischaemic stroke accompanied by massive space-occupying oedema represents one of the major unsolved problems in neurocritical care medicine. Despite maximum intensive care, the prognosis of these patients is poor, with case fatality rates as high as 80%. Therefore, the term 'malignant brain infarction' was coined. Because conservative treatment strategies to limit brain tissue shift almost consistently fail, these massive infarctions often are regarded as an untreatable disease. The introduction of decompressive surgery (hemicraniectomy) has completely changed this point of view, suggesting that mortality rates may be reduced to approximately 20%. However, critics have always argued that the reduction in mortality may be outweighed by an accompanying increase in severe disability. Due to the lack of conclusive evidence of efficacy from randomised trials, controversy over the benefit of these treatment strategies remained, leading to large regional differences in the application of this procedure. Meanwhile, data from randomised trials confirm the results of former observational studies, demonstrating that hemicraniectomy not only significantly reduces mortality but also significantly improves clinical outcome without increasing the number of completely dependent patients. Hypothermia is another promising treatment option but still needs evidence of efficacy from randomised controlled trials before it may be recommended for clinical routine use. This review gives the reader an integrated view of the current status of treatment options in massive hemispheric brain infarction, based on the available data of clinical trials, including the most recent data from randomised trials published in 2007.

[Recommendations of the European Stroke Initiative for the diagnosis and treatment of spontaneous intracerebral haemorrhage]

This article summarises the recommendations for the management of managing patients with intracerebral haemorrhage published in 2006 by the European Stroke Initiative (EUSI) on behalf of the European Stroke Council (ESC), the European Neurological Society (ENS), and the European Federation of Neurological Societies (EFNS).

The challenge of blood pressure management in neurologic emergencies

Hypertensive crises are commonly seen in the emergency department, and acute stroke is often the inciting etiology of a hypertensive crisis. Cerebral autoregulation is disrupted in acute stroke, and efforts to lower blood pressure may reduce cerebral perfusion and worsen outcomes. Although most patients with stroke have elevated blood pressure, evidence from clinical trials to guide therapy are scarce. Current national guidelines recommend lowering blood pressure after stroke only if end-organ damage is present or if systolic/diastolic blood pressures exceed 220/120 or 185/110 mm Hg in patients ineligible and in those eligible to receive thrombolytic drug therapy, respectively. Recommended pharmacologic interventions for elevated blood pressure after acute ischemic stroke include labetalol, nicardipine, or nitroprusside, depending on the severity of the elevation. Similar recommendations have been made for intracerebral hemorrhage. Subarachnoid hemorrhage is managed with nimodipine and other calcium channel blockers to prevent vasospasm and improve clinical outcomes. Data from ongoing clinical trials may improve guidance about the management of elevated blood pressure after acute stroke.

Hemicraniectomy after middle cerebral artery infarction with life-threatening Edema trial (HAMLET). Protocol for a randomised controlled trial of decompressive surgery in space-occupying hemispheric infarction

Background

Patients with a hemispheric infarct and massive space-occupying brain oedema have a poor prognosis. Despite maximal conservative treatment, the case fatality rate may be as high as 80%, and most survivors are left severely disabled. Non-randomised studies suggest that decompressive surgery reduces mortality substantially and improves functional outcome of survivors. This study is designed to compare the efficacy of decompressive surgery to improve functional outcome with that of conservative treatment in patients with space-occupying supratentorial infarction

Methods

The study design is that of a multi-centre, randomised clinical trial, which will include 112 patients aged between 18 and 60 years with a large hemispheric infarct with space-occupying oedema that leads to a decrease in consciousness. Patients will be randomised to receive either decompressive surgery in combination with medical treatment or best medical treatment alone. Randomisation will be stratified for the intended mode of conservative treatment (intensive care or stroke unit care). The primary outcome measure will be functional outcome, as determined by the score on the modified Rankin Scale, at one year.

Revascularização clínica e intervencionista no acidente vascular cerebral isquêmico agudo: opinião nacional

Este artigo apresenta as conclusões sobre revascularização clínica e intervencionista no acidente vascular cerebral isquêmico agudo, um dos temas discutidos na reunião "Opinião Nacional sobre o Tratamento do AVC". Tratou-se de reunião promovida e coordenada pela Sociedade Brasileira de Doenças Cerebrovasculares, com neurologistas especializados em doenças cerebrovasculares, que analisaram e discutiram as evidências e experiências atuais sobre o uso de trombólise e técnicas intervencionistas em pacientes com acidente vascular cerebral isquêmico agudo.

Late spontaneous recanalization of acute internal carotid artery occlusion

Spontaneous internal carotid recanalization has been infrequently observed, and when it has been reported, it has most commonly occurred early after a stroke. We report a case of a patient with late spontaneous recanalization of the internal carotid artery (ICA) that occurred within 6 months to 1 year after the initial diagnosis of occlusion during the course of a stroke. This event allowed the patient to undergo a successful surgical intervention. A suggestion is made about the mechanism of this phenomenon and an implication about changes in the follow-up strategies of these patients is presented.