Monitoring intracranial pressure in patients with malignant middle cerebral artery infarction: is it useful?

Poroelastic modelling of brain tissue swelling and decompressive craniectomy treatment in ischaemic stroke

Brain oedema or tissue swelling that develops after ischaemic stroke can cause detrimental effects, including brain herniation and increased intracranial pressure (ICP). These effects can be reduced by performing a decompressive craniectomy (DC) operation, in which a portion of the skull is removed to allow swollen brain tissue to expand outside the skull. In this study, a poroelastic model is used to investigate the effect of brain ischaemic infarct size and location on the severity of brain tissue swelling. Furthermore, the model will also be used to evaluate the effectiveness of DC surgery as a treatment for brain tissue swelling after ischaemia. The poroelastic model consists of two equations: one describing the elasticity of the brain tissue and the other describing the changes in the interstitial tissue pressure. The model is applied on an idealized brain geometry, and it is found that infarcts with radius larger than approximately 14 mm and located near the lateral ventricle produce worse brain midline shift, measured through lateral ventricle compression. Furthermore, the model is also able to show the positive effect of DC treatment in reducing the brain midline shift by allowing part of the brain tissue to expand through the skull opening. However, the model does not show a decrease in the interstitial pressure during DC treatment. Further improvement and validation could enhance the capability of the proposed poroelastic model in predicting the occurrence of brain tissue swelling and DC treatment post ischaemia.

Role of decompressive craniectomy in the management of acute ischemic stroke (Review)

The application of decompressive craniectomy (DC) is thoroughly documented in the management of brain edema, particularly following traumatic brain injury. However, an increasing amount of concern is developing among the universal medical community as regards the application of DC in the treatment of other causes of brain edema, such as subarachnoid hemorrhage, cerebral hemorrhage, sinus thrombosis and encephalitis. Managing stroke continues to remain challenging, and demands the aggressive and intensive consulting of a number of medical specialties. Middle cerebral artery (MCA) infarcts, which consist of 1-10% of all supratentorial infarcts, are often associated with mass effects, and high mortality and morbidity rates. Over the past three decades, a number of neurosurgical medical centers have reported their experience with the application of DC in the treatment of malignant MCA infarction with varying results. In addition, over the past decade, major efforts have been dedicated to multicenter randomized clinical trials. The present study reviews the pertinent literature to outline the use of DC in the management of malignant MCA infarction. The PubMed database was systematically searched for the following terms: 'Malignant cerebral infarction', 'surgery for stroke', 'DC for cerebral infarction', and all their combinations. Case reports were excluded from the review. The articles were categorized into a number of groups; the majority of these were human clinical studies, with a few animal experimental clinical studies. The surgical technique involved was DC, or hemicraniectomy. Other aspects that were included in the selection of articles were methodological characteristics and the number of patients. The multicenter randomized trials were promising. The mortality rate has unanimously decreased. As for the functional outcome, different scales were employed; the Glasgow Outcome Scale Extended was not sufficient; the Modified Rankin Scale and Bathel index, as well as other scales, were applied. Other aspects considered were demographics, statistics and the very interesting radiological ones. There is no doubt that DC decreases mortality rates, as shown in all clinical trials. Functional outcome appears to be the goal standard in modern-era neurosurgery, and quality of life should be further discussed among the medical community and with patient consent.

Definition, prediction, prevention and management of patients with severe ischemic stroke and large infarction

ABSTRACT

Severe ischemic stroke carries a high rate of disability and death. The severity of stroke is often assessed by the degree of neurological deficits or the extent of brain infarct, defined as severe stroke and large infarction, respectively. Critically severe stroke is a life-threatening condition that requires neurocritical care or neurosurgical intervention, which includes stroke with malignant brain edema, a leading cause of death during the acute phase, and stroke with severe complications of other vital systems. Early prediction of high-risk patients with critically severe stroke would inform early prevention and treatment to interrupt the malignant course to fatal status. Selected patients with severe stroke could benefit from intravenous thrombolysis and endovascular treatment in improving functional outcome. There is insufficient evidence to inform dual antiplatelet therapy and the timing of anticoagulation initiation after severe stroke. Decompressive hemicraniectomy (DHC) <48 h improves survival in patients aged <60 years with large hemispheric infarction. Studies are ongoing to provide evidence to inform more precise prediction of malignant brain edema, optimal indications for acute reperfusion therapies and neurosurgery, and the individualized management of complications and secondary prevention. We present an evidence-based review for severe ischemic stroke, with the aims of proposing operational definitions, emphasizing the importance of early prediction and prevention of the evolution to critically severe status, summarizing specialized treatment for severe stroke, and proposing directions for future research.

Current and Emerging Endovascular and Neurocritical Care Management Strategies in Large-Core Ischemic Stroke

The volume of infarcted tissue in patients with ischemic stroke is consistently associated with increased morbidity and mortality. Initial studies of endovascular thrombectomy for large-vessel occlusion excluded patients with established large-core infarcts, even when large volumes of salvageable brain tissue were present, due to the high risk of hemorrhagic transformation and reperfusion injury. However, recent retrospective and prospective studies have shown improved outcomes with endovascular thrombectomy, and several clinical trials were recently published to evaluate the efficacy of endovascular management of patients presenting with large-core infarcts. With or without thrombectomy, patients with large-core infarcts remain at high risk of in-hospital complications such as hemorrhagic transformation, malignant cerebral edema, seizures, and others. Expert neurocritical care management is necessary to optimize blood pressure control, mitigate secondary brain injury, manage cerebral edema and elevated intracranial pressure, and implement various neuroprotective measures. Herein, we present an overview of the current and emerging evidence pertaining to endovascular treatment for large-core infarcts, recent advances in neurocritical care strategies, and their impact on optimizing patient outcomes.

Surgery for Malignant Acute Ischemic Stroke: A Narrative Review of the Knowns and Unknowns

Malignant acute ischemic stroke (AIS) is characterized by acute neurological deterioration caused by progressive space-occupying brain edema, often occurring in the first hours to days after symptom onset. Without any treatment, the result is often fatal. Despite advances in treatment for AIS, up to 80% of patients with a large hemispheric stroke or cerebellar stroke are at risk of poor outcome. Decompressive surgery can be life-saving in a subgroup of patients with malignant AIS, but uncertainties exist on patient selection, predictors of malignant infarction, perioperative management, and timing of intervention. Although survivors are left disabled, most agree with the original decision to undergo surgery and would make the same decision again. In this narrative review, we focus on the clinical and radiological predictors of malignant infarction in AIS and outline the technical aspects of decompressive surgery as well as duraplasty and cranioplasty. We discuss the current evidence and recommendations for surgery in AIS, highlighting gaps in knowledge, and suggest directions for future studies. KEY POINTS: · Acute ischemic stroke from occlusion of a proximal intracranial artery can progress quickly to malignant edema, which can be fatal in 80% of patients despite medical management.. · Decompression surgery is life-saving within 48 hours of stroke onset, but the benefits beyond this time and in the elderly are unknown.. · Decompressive surgery is associated with high morbidity, particularly in the elderly. The decision to operate must be made after considering the individual's preference and expectations of quality of life in the context of the clinical condition.. · Further studies are needed to refine surgical technique including value of duraplasty and understand the role monitoring intracranial pressure during and after decompressive surgery.. · More studies are needed on the pathophysiology of malignant cerebral edema, prediction models including imaging and biomarkers to identify which subgroup of patients will benefit from decompressive surgery.. · More research is needed on factors associated with morbidity and mortality after cranioplasty, safety and efficacy of implants, and comparisons between them.. · Further studies are needed to assess the long-term effects of physical disability and quality of life of survivors after surgery, particularly those with severe neurological deficits..

Optic nerve sheath diameter and optic nerve sheath diameter/eyeball transverse diameter ratio in prediction of malignant progression in ischemic stroke

Background

The optic nerve sheath diameter (ONSD)/eyeball transverse diameter (ETD) ratio has been suggested in the evaluation of intracranial pressure (ICP). The aim of this study was to evaluate the predictive value of ONSD and ONSD/ETD in relation to risk for secondary malignant middle cerebral artery infarction (MMI).

Methods

A total of 91 patients with MCA occlusion were included in this study. Data were divided into two groups based on development of MMI or not. ONSD and ETD were measured by unenhanced computed tomography (CT). The differences in ONSD and the ONSD/ETD ratios between the MMI and non-MMI groups were compared. Receiver operating characteristic curve analyses were used to test the diagnostic value of ONSD and ONSD/ETD independently, to predict MMI.

Results

The ONSD in the MMI group and non-MMI group were 5.744 ± 0.140 mm and 5.443 ± 0.315 mm, respectively (P = 0.001). In addition, the ONSD/ETD ratios in the MMI group and non-MMI group were 0.258 ± 0.008 and 0.245 ± 0.006, respectively (P = 0.001). The receiver operating characteristic (ROC) curve demonstrated an area under the curve (AUC) for ONSD of 0.812 [95% confidence interval (CI): 0.718–0.906, P = 0.001], with a sensitivity of 97.4% and a specificity of 66.0% at the cut-off value of 5.520 mm. The AUC for ONSD/ETD ratio in predicting occurrence of MMI was 0.895 (95% CI: 0.823–0.968, P = 0.001), with a sensitivity of 84.2% and a specificity of 92.5% at a cut-off value of 0.250.

Conclusion

In acute stroke patients with massive cerebral infarction, an increased ONSD or ONSD/ETD ratio increases the odds of malignant progression and may be used as an indicator for emergent therapeutic interventions. In addition, the ONSD/ETD ratio may be more valuable than ONSD in predicting the malignant progression of acute stroke patients.

Intracranial Pressure as an Objective Biomarker of Decompression Adequacy in Large Territory Infarction: A Multicenter Observational Study

Background

Decompressive craniectomy (DC) improves the survival and functional outcomes in patients with malignant cerebral infarction. Currently, there are no objective intraoperative markers that indicates adequate decompression. We hypothesise that closure intracranial pressure (ICP) correlates with postoperative outcomes.

Methods

This is a multicentre retrospective review of all 75 DCs performed for malignant cerebral infarction. The patients were divided into inadequate ICP (iICP) and good ICP (gICP) groups based on a suitable ICP threshold determined with tiered receiver operating characteristic and association analysis. Multivariable logistic regression was performed for various postoperative outcomes.

Results

An ICP threshold of 7 mmHg was determined, with 36 patients (48.0%) and 39 patients (52.0%) in the iICP and gICP group, respectively. After adjustment, postoperative osmotherapy usage was more likely in the iICP group (OR 6.32, p = 0.003), and when given, was given for a longer median duration (iICP, 4 days; gICP, 1 day, p = 0.003). There was no difference in complications amongst both groups. When an ICP threshold of 11 mmHg was applied, there was significant difference in the duration on ventilator (ICP ≥11 mmHg, 3–9 days, ICP <11 mmHg, 3–5 days, p = 0.023).

Conclusion

Surgical decompression works complementarily with postoperative medical therapy to manage progressive cerebral edema in malignant cerebral infarctions. This is a retrospective study which showed that closure ICP, a novel objective intraoperative biomarker, is able to guide the adequacy of DC in this condition. Various surgical manoeuvres can be performed to ensure that this surgical aim is accomplished.

Transcranial Doppler as a screening test to exclude intracranial hypertension in brain-injured patients: the IMPRESSIT-2 prospective multicenter international study

Background

Alternative noninvasive methods capable of excluding intracranial hypertension through use of transcranial Doppler (ICPtcd) in situations where invasive methods cannot be used or are not available would be useful during the management of acutely brain-injured patients. The objective of this study was to determine whether ICPtcd can be considered a reliable screening test compared to the reference standard method, invasive ICP monitoring (ICPi), in excluding the presence of intracranial hypertension.

Methods

This was a prospective, international, multicenter, unblinded, diagnostic accuracy study comparing the index test (ICPtcd) with a reference standard (ICPi), defined as the best available method for establishing the presence or absence of the condition of interest (i.e., intracranial hypertension). Acute brain-injured patients pertaining to one of four categories: traumatic brain injury (TBI), subarachnoid hemorrhage (SAH), intracerebral hemorrhage (ICH) or ischemic stroke (IS) requiring ICPi monitoring, were enrolled in 16 international intensive care units. ICPi measurements (reference test) were compared to simultaneous ICPtcd measurements (index test) at three different timepoints: before, immediately after and 2 to 3 h following ICPi catheter insertion. Sensitivity, specificity, positive (PPV) and negative predictive values (NPV) were calculated at three different ICPi thresholds (> 20, > 22 and > 25 mmHg) to assess ICPtcd as a bedside real-practice screening method. A receiver operating characteristic (ROC) curve analysis with the area under the curve (AUC) was used to evaluate the discriminative accuracy and predictive capability of ICPtcd.

Results

Two hundred and sixty-two patients were recruited for final analysis. Intracranial hypertension (> 22 mmHg) occurred in 87 patients (33.2%). The total number of paired comparisons between ICPtcd and ICPi was 687. The NPV was elevated (ICP > 20 mmHg = 91.3%, > 22 mmHg = 95.6%, > 25 mmHg = 98.6%), indicating high discriminant accuracy of ICPtcd in excluding intracranial hypertension. Concordance correlation between ICPtcd and ICPi was 33.3% (95% CI 25.6–40.5%), and Bland–Altman showed a mean bias of -3.3 mmHg. The optimal ICPtcd threshold for ruling out intracranial hypertension was 20.5 mmHg, corresponding to a sensitivity of 70% (95% CI 40.7–92.6%) and a specificity of 72% (95% CI 51.9–94.0%) with an AUC of 76% (95% CI 65.6–85.5%).

Conclusions and relevance

ICPtcd has a high NPV in ruling out intracranial hypertension and may be useful to clinicians in situations where invasive methods cannot be used or not available.

Trial registration: NCT02322970.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-022-03978-2.

European Stroke Organisation (ESO) guidelines on the management of space-occupying brain infarction

Space-occupying brain oedema is a potentially life-threatening complication in the first days after large hemispheric or cerebellar infarction. Several treatment strategies for this complication are available, but the size and quality of the scientific evidence on which these strategies are based vary considerably. The aim of this Guideline document is to assist physicians in their management decisions when treating patients with space-occupying hemispheric or cerebellar infarction. These Guidelines were developed based on the European Stroke Organisation (ESO) standard operating procedure and followed the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) approach. A working group identified 13 relevant questions, performed systematic reviews and meta-analyses of the literature, assessed the quality of the available evidence, and wrote evidence-based recommendations. An expert consensus statement was provided if not enough evidence was available to provide recommendations based on the GRADE approach. We found high-quality evidence to recommend surgical decompression to reduce the risk of death and to increase the chance of a favourable outcome in adult patients aged up to and including 60 years with space-occupying hemispheric infarction who can be treated within 48 hours of stroke onset, and low-quality evidence to support this treatment in older patients. There is continued uncertainty about the benefit and risks of surgical decompression in patients with space-occupying hemispheric infarction if this is done after the first 48 hours. There is also continued uncertainty about the selection of patients with space-occupying cerebellar infarction for surgical decompression or drainage of cerebrospinal fluid. These Guidelines further provide details on the management of specific subgroups of patients with space-occupying hemispheric infarction, on the value of monitoring of intracranial pressure, and on the benefits and risks of medical treatment options. We encourage new high-quality studies assessing the risks and benefits of different treatment strategies for patients with space-occupying brain infarction.

Neurologic Assessment of the Neurocritical Care Patient

Sedation is a ubiquitous practice in ICUs and NCCUs. It has the benefit of reducing cerebral energy demands, but also precludes an accurate neurologic assessment. Because of this, sedation is intermittently stopped for the purposes of a neurologic assessment, which is termed a neurologic wake-up test (NWT). NWTs are considered to be the gold-standard in continued assessment of brain-injured patients under sedation. NWTs also produce an acute stress response that is accompanied by elevations in blood pressure, respiratory rate, heart rate, and ICP. Utilization of cerebral microdialysis and brain tissue oxygen monitoring in small cohorts of brain-injured patients suggests that this is not mirrored by alterations in cerebral metabolism, and seldom affects oxygenation. The hard contraindications for the NWT are preexisting intracranial hypertension, barbiturate treatment, status epilepticus, and hyperthermia. However, hemodynamic instability, sedative use for primary ICP control, and sedative use for severe agitation or respiratory distress are considered significant safety concerns. Despite ubiquitous recommendation, it is not clear if additional clinically relevant information is gleaned through its use, especially with the contemporaneous utilization of multimodality monitoring. Various monitoring modalities provide unique and pertinent information about neurologic function, however, their role in improving patient outcomes and guiding treatment plans has not been fully elucidated. There is a paucity of information pertaining to the optimal frequency of NWTs, and if it differs based on type of injury. Only one concrete recommendation was found in the literature, exemplifying the uncertainty surrounding its utility. The most common sedative used and recommended is propofol because of its rapid onset, short duration, and reduction of cerebral energy requirements. Dexmedetomidine may be employed to facilitate serial NWTs, and should always be used in the non-intubated patient or if propofol infusion syndrome (PRIS) develops. Midazolam is not recommended due to tissue accumulation and residual sedation confounding a reliable NWT. Thus, NWTs are well-tolerated in selected patients and remain recommended as the gold-standard for continued neuromonitoring. Predicated upon one expert panel, they should be performed at least one time per day. Propofol or dexmedetomidine are the main sedative choices, both enabling a rapid awakening and consistent NWT.

What is the Role of Hyperosmolar Therapy in Hemispheric Stroke Patients?

The role of hyperosmolar therapy (HT) in large hemispheric ischemic or hemorrhagic strokes remains a controversial issue. Past and current stroke guidelines state that it represents a reasonable therapeutic measure for patients with either neurological deterioration or intracranial pressure (ICP) elevations documented by ICP monitoring. However, the lack of evidence for a clear effect of this therapy on radiological tissue shifts and clinical outcomes produces uncertainty with respect to the appropriateness of its implementation and duration in the context of radiological mass effect without clinical correlates of neurological decline or documented elevated ICP. In addition, limited data suggest a theoretical potential for harm from the prophylactic and protracted use of HT in the setting of large hemispheric lesions. HT exerts effects on parenchymal volume, cerebral blood volume and cerebral perfusion pressure which may ameliorate global ICP elevation and cerebral blood flow; nevertheless, it also holds theoretical potential for aggravating tissue shifts promoted by significant interhemispheric ICP gradients that may arise in the setting of a large unilateral supratentorial mass lesion. The purpose of this article is to review the literature in order to shed light on the effects of HT on brain tissue shifts and clinical outcome in the context of large hemispheric strokes, as well as elucidate when HT should be initiated and when it should be avoided.

Critical care management of the patient with an acute ischaemic stroke

Acute ischaemic stroke is a leading cause of morbidity and mortality worldwide. In the UK alone, there are more than 100 000 strokes per year, causing 38 000 deaths. While the incidence remains high, there has been significant medical progress in reducing mortality following a stroke. Admission of patients to specialised stroke units has led to an improvement in clinical outcomes, but the role of intensive care is less well defined. This article reviews the current critical care management and neuro-therapeutic options after an acute ischaemic stroke.

Invasive Monitoring of Intracranial Pressure After Decompressive Craniectomy in Malignant Stroke

BACKGROUND AND PURPOSE

The role of decompressive hemicraniectomy (DC) in malignant cerebral infarction (MCI) has clearly been established, but little is known about the course of intracranial pressure (ICP) in patients undergoing this surgical measure. In this study, we investigated the role of invasive ICP monitoring in patients after DC for MCI, postulating that postoperative ICP predicts mortality.

METHODS

In this retrospective observational study of MCI patients undergoing DC, ICP were recorded continuously in hourly intervals for the first 72 hours after DC. For every hour, mean ICP was calculated, pooling ICP of every patient. A receiver operating characteristic analysis was performed for hourly mean ICP. A subgroup analysis by age (≥60 years and <60 years) was also performed.

RESULTS

A total of 111 patients were analyzed, with 29% mortality rate in patients <60 years, and 41% in patients ≥60 years. A threshold of 10 mm Hg within the first 72 postoperative hours was a reliable predictor of mortality in MCI, with an acceptable sensitivity of 70% and high specificity of 97%. Established predictors of mortality failed to predict mortality.

CONCLUSIONS

Our study suggests the need to reevaluate postoperative ICP after DC in MCI and calls for a redefinition of ICP thresholds in these patients to indicate further therapy.

Decompressive hemicraniectomy in ischemic stroke

Malignant hemispheric stroke (MHS) is a life-threatening event, associated with high morbidity and mortality. Decompressive hemicraniectomy (DHS) is the treatment of choice to relieve the emerging space-occupying brain edema. This review details the pathophysiological and scientific background, considerations for clinical decision making, surgical treatment and impact on the patients' outcome. Although surgery reduces mortality significantly, the probability for unfavorable outcome is still high in selected cases. While former randomized controlled studies aimed for the prevention of the primary cause, the current research focuses on the treatment and prevention of secondary neurological injury.

Comparison of equiosmolar doses of 10% hypertonic saline and 20% mannitol for controlling intracranial hypertention in patients with large hemispheric infarction

OBJECTIVE

We conducted this prospective self-crossover controlled trial to compare the efficacy and safety of 10 % hypertonic saline (HS) and 20 % mannitol in doses of similar osmotic burden for the treatment of increased intracranial pressure (ICP) in patients with large hemispheric infarction (LHI).

PATIENTS AND METHODS

Patients with LHI were enrolled from January 2017 to January 2018. We used an alternating treatment protocol to compare the effects of HS with mannitol given for episodes of increased ICP in patients with LHI. Indicators such as ICP, mean arterial pressure (MAP) and cerebral perfusion pressure (CPP) were continuously monitored at regular intervals for 240 min after initiation of infusion. Electrolytes, plasma osmolality and renal functions were measured before and 240 min after initiation of infusion to compare the efficacy and safety of the two drugs.

RESULTS

A total of 49 episodes of increased ICP occurred in 14 patients with LHI, of which 24 were infused with 10 % HS and 25 with 20 % mannitol. Both the treatments were equally effective in reducing ICP (P < 0.01). The differences in the duration and degree of reduction were not significant between the groups (P > 0.05). Although both the osmolar agents decreased MAP, the degree was greater in the mannitol group (P < 0.05) at T120. The increase in CPP was greater in the HS group compared with the mannitol group (P < 0.05) at T120. However, HS was associated with faster heart rate (HR) and higher serum chloride levels (P < 0.05). Changes in serum sodium levels and osmolality were not significant between the groups in spite of being higher in the HS group.

CONCLUSIONS

Both the drugs can serve as first-line agents for treating intracranial hypertension caused by LHI and should be selected rationally according to the differences in efficacy and adverse effects.

Is Spreading Depolarization a Risk Factor for Late Epilepsy? A Prospective Study in Patients with Traumatic Brain Injury and Malignant Ischemic Stroke Undergoing Decompressive Craniectomy

OBJECTIVE

Spreading depolarizations (SDs) have been described in patients with ischemic and haemorrhagic stroke, traumatic brain injury, and migraine with aura, among other conditions. The exact pathophysiological mechanism of SDs is not yet fully established. Our aim in this study was to evaluate the relationship between the electrocorticography (ECoG) findings of SDs and/or epileptiform activity and subsequent epilepsy and electroclinical outcome.

METHODS

This was a prospective observational study of 39 adults, 17 with malignant middle cerebral artery infarction (MMCAI) and 22 with traumatic brain injury, who underwent decompressive craniectomy and multimodal neuromonitoring including ECoG in penumbral tissue. Serial electroencephalography (EEG) recordings were obtained for all surviving patients. Functional disability at 6 and 12 months after injury were assessed using the Barthel, modified Rankin (mRS), and Extended Glasgow Outcome (GOS-E) scales.

RESULTS

SDs were recorded in 58.9% of patients, being more common-particularly those of isoelectric type-in patients with MMCAI (p < 0.04). At follow-up, 74.7% of patients had epileptiform abnormalities on EEG and/or seizures. A significant correlation was observed between the degree of preserved brain activity on EEG and disability severity (R [mRS]: + 0.7, R [GOS-E, Barthel]: - 0.6, p < 0.001), and between the presence of multifocal epileptiform abnormalities on EEG and more severe disability on the GOS-E at 6 months (R: - 0.3, p = 0.03) and 12 months (R: - 0.3, p = 0.05). Patients with more SDs and higher depression ratios scored worse on the GOS-E (R: - 0.4 at 6 and 12 months) and Barthel (R: - 0.4 at 6 and 12 months) disability scales (p < 0.05). The number of SDs (p = 0.064) and the depression ratio (p = 0.1) on ECoG did not show a statistically significant correlation with late epilepsy.

CONCLUSIONS

SDs are common in the cortex of ischemic or traumatic penumbra. Our study suggests an association between the presence of SDs in the acute phase and worse long-term outcome, although no association with subsequent epilepsy was found. More comprehensive studies, involving ECoG and EEG could help determine their association with epileptogenesis.

Optic nerve sheath diameter change in prediction of malignant cerebral edema in ischemic stroke: an observational study

Background

In acute large anterior circulation infarct patients with large core volume, we evaluated the role of optic nerve sheath diameter (ONSD) change rates in prediction of malignant progression.

Methods

We performed a retrospective observational study including patients with anterior circulation acute ischemic stroke with large ischemic cores from January 2010 to October 2017. Primary outcome was defined as undergoing decompressive surgery or death due to severe cerebral edema, and termed malignant progression. Patients were divided into malignant progressors and nonprogressors. Malignant progression was divided into early progression that occurred before D1 CT, and late progression that occurred afterwards. Retrospective analysis of changes in mean ONSD/eyeball transverse diameter (ETD) ratio, and midline shifting (MLS) were evaluated on serial computed tomography (CT). Through analysis of CT at baseline, postprocedure, and at D1, the predictive ability of time based change in ONSD/ETD ratio in predicting malignant progression was evaluated.

Results

A total of 58 patients were included. Nineteen (32.8%) were classified as malignant; 12 early, and 7 late progressions. In analysis of CT_{postprocedure}, A 1 mm/hr. rate of change in MLS during the CT_baseline-CT_{postprocedure} time phase lead to a 6.7 fold increased odds of early malignant progression (p < 0.05). For ONSD/ETD, 1%/hr. change lead to a 1.6 fold increased odds, but this association was trending (p = 0.249). In the CT_D1, 1%/day change of ONSD/ETD in the CT_baseline-CT_D1 time phase lead to a 1.4 fold increased odds of late malignant progression (p = 0.021) while 1 mm/day rate of change in MLS lead to a 1.5 fold increased odds (p = 0.014).

Conclusions

The rate of ONSD/ETD changes compared to baseline at D1 CT can be a predictor of late malignant progression along with MLS. ONSD/ETD change rates evaluated at postprocedure did not predict early malignant progression.

Decompressive craniectomy in pediatric non-traumatic intracranial hypertension: a single center experience

Purpose: To study the clinical profile and predictors of outcome in children undergoing decompressive craniectomy (DC) for non-traumatic intracranial hypertension (ICH).Materials and methods: Mixed observational study of children, aged 1 month-12 years, who underwent DC for non-traumatic ICH in a tertiary care pediatric intensive care unit from 2012 to 2017. Data on clinical profile and outcome were retrieved retrospectively and survivors were assessed prospectively. The primary outcome was neurological outcome using Glasgow Outcome Scale-Extended (GOS-E) at minimum 6 months' post-discharge. GOS-E of 1-4 were classified as a poor and 5-8 as a good outcome.Results: Thirty children, median (IQR) age of 6.5 (2, 50) months, underwent DC; of which 26 (86.7%) were boys. Altered sensorium (n = 26, 86.7%), seizures (n = 25, 83.3%), pallor (n = 19, 63.3%) and anisocoria (n = 14, 46.7%) were common signs and symptoms. Median (IQR) Glasgow Coma Scale at admission was 9 (6,11). Commonest etiology was intracranial bleed (n = 24; 80%). Median (IQR) time to DC was 24 (24,72) h. Eight (26.7%) children died; 2 during PICU stay and 6 during follow-up. Neurological sequelae at discharge (n = 28) were seizures (n = 25; 89.2%) and hemiparesis (n = 16; 57.1%). Twenty-one children were followed-up at median (IQR) duration of 12 (6,54) months. Good neurological outcome was seen in 14/29 (48.2%) and hemiparesis in 10/21 (47.6%) patients. On regression analysis, anisocoria at admission was an independent predictor of poor outcome [OR 7.33; 95%CI: 1.38-38.87; p = 0.019].Conclusions: DC is beneficial in children with non-traumatic ICH due to a focal pathology and midline shift. Evidence on indications and timing of DC in NTC is still evolving.

Brain ultrasonography: methodology, basic and advanced principles and clinical applications. A narrative review

Brain ultrasonography can be used to evaluate cerebral anatomy and pathology, as well as cerebral circulation through analysis of blood flow velocities. Transcranial colour-coded duplex sonography is a generally safe, repeatable, non-invasive, bedside technique that has a strong potential in neurocritical care patients in many clinical scenarios, including traumatic brain injury, aneurysmal subarachnoid haemorrhage, hydrocephalus, and the diagnosis of cerebral circulatory arrest. Furthermore, the clinical applications of this technique may extend to different settings, including the general intensive care unit and the emergency department. Its increasing use reflects a growing interest in non-invasive cerebral and systemic assessment. The aim of this manuscript is to provide an overview of the basic and advanced principles underlying brain ultrasonography, and to review the different techniques and different clinical applications of this approach in the monitoring and treatment of critically ill patients.

Automated Pupillometry and Detection of Clinical Transtentorial Brain Herniation: A Case Series

Introduction

Transtentorial herniation (TTH) is a life-threatening neurologic condition that typically results from expansion of supratentorial mass lesions. A change in bedside pupillary examination is central to the clinical diagnosis of TTH. Materials and.

Methods

To quantify the changes in the pupillary examination that precede and accompany TTH and its treatment, we evaluated 12 episodes of herniation in three patients with supratentorial mass lesions using automated pupillometry (NeurOptics, Inc., Irvine, CA). Herniation was defined clinically by the onset of fixed and dilated pupils in association with decreased levels of consciousness. Automated pupillometry was measured simultaneously with the bedside clinical examination, but the clinical team was blinded to these results and could not act on the data. Data from the pupillometer were downloaded 1-2 times per week onto a secured laptop, and data processing was facilitated by the use of Mathematica 8.0.

Results

Neurologic Pupil Index measurements, values generated by the pupillometer based on an algorithm that incorporates pupillary size and reactivity in a normal population, were found to be abnormal before 73% of TTHs. This abnormality occurred at a median of 7.4 h before TTH. All episodes of TTH were reversed after clinical intervention at a median of 43 min after the event. The value did not fall to 0 in 42% of clinical herniations, but it did decrease to very abnormal values of 0.5-0.8.

Conclusions

The potential of automated pupillometry to guide the management of severely injured neurologic patients is intriguing and warrants further study in the critical care unit and beyond. The utility of a portable device in the combat setting may allow for triage of patients with severe neurologic injury.

Role of Decompressive Craniectomy in Ischemic Stroke

Ischemic stroke is one of the leading causes for death and disability worldwide. In patients with large space-occupying infarction, the subsequent edema complicated by transtentorial herniation poses a lethal threat. Especially in patients with malignant middle cerebral artery infarction, brain swelling secondary to the vessel occlusion is associated with high mortality. By decompressive craniectomy, a significant proportion of the skull is surgically removed, allowing the ischemic tissue to shift through the surgical defect rather than to the unaffected regions of the brain, thus avoiding secondary damage due to increased intracranial pressure. Several studies have shown that decompressive craniectomy reduces the mortality rate in patients with malignant cerebral artery infarction. However, this is done for the cost of a higher proportion of patients who survive with severe disability. In this review, we will describe the clinical and radiological features of malignant middle cerebral artery infarction and the role of decompressive craniectomy and additional therapies in this condition. We will also discuss large cerebellar stroke and the possibilities of suboccipital craniectomy.

Update in the Early Management and Reperfusion Strategies of Patients with Acute Ischemic Stroke

Acute ischemic stroke (AIS) remains a leading cause of death and long-term disability. The paradigms on prehospital care, reperfusion therapies, and postreperfusion management of patients with AIS continue to evolve. After the publication of pivotal clinical trials, endovascular thrombectomy has become part of the standard of care in selected cases of AIS since 2015. New stroke guidelines have been recently published, and the time window for mechanical thrombectomy has now been extended up to 24 hours. This review aims to provide a focused up-to-date review for the early management of adult patients with AIS and introduce the new upcoming areas of ongoing research.

The Wessex modified Richmond Sedation Scale as a novel tool for monitoring patients at risk of malignant MCA syndrome

BACKGROUND

The Wessex Modified Richmond Sedation Scale (WMRSS) has been developed with the aim of improving the early identification of patients requiring decompressive hemicraniectomy for malignant middle cerebral artery syndrome (MMS). The objective of this study was to evaluate the WMRSS against the Glasgow Coma Scale (GCS).

METHODS

A retrospective study was conducted of patients admitted to our unit for observation of MMS. Data were obtained on WMRSS and GCS recordings from admission up to 120-h post-ictus. Patients' meeting inclusion criteria were recommended for theatre based on subsequent deteriorations in consciousness on either WMRSS or GCS from a 6-h post-stroke baseline, after ruling out non-neurological causes.

RESULTS

Approximately, 60% of those eligible for monitoring were not recommended for theatre, and none died; however, these patients continued to demonstrate some variability in recorded conscious level. Patients requiring surgical intervention showed earlier drops in WMRSS compared to GCS. Neither the GCS nor the WMRSS on admission predicted the subsequent need for decompressive surgery. There was no increase in mortality with the introduction of WMRSS.

CONCLUSIONS

WMRSS adds value to monitoring MMS by indicating need for surgery prior to GCS. Early reduction in consciousness may not be sufficient for proceeding to surgical intervention, but subsequent reduction in consciousness may be a more appropriate criterion for surgery.

Intracranial pressure in patients undergoing decompressive craniectomy: new perspective on thresholds

OBJECTIVE

Decompressive craniectomy (DC) is an established part of treatment in patients suffering from malignant infarction of the middle cerebral artery (MCA) or traumatic brain injury (TBI). However, no clear evidence for intracranial pressure (ICP)-guided therapy after DC exists. The lack of this evidence might be due to the frequently used, but simplified threshold for ICP of 20 mm Hg, which determines further therapy. Therefore, the objective of this study was to evaluate this threshold's accuracy and to investigate the course of ICP values with respect to neurological outcome.

METHODS

Data on clinical characteristics and parameters of the ICP course on the intensive care unit were collected retrospectively in 102 patients who underwent DC between December 2007 and April 2014 at the authors' institution. The postoperative ICP course in the first 168 hours was recorded and analyzed. From these findings, ICP thresholds discriminating favorable from unfavorable outcome were calculated using conditional inference tree analysis. Additionally, survival analysis was performed using the Kaplan-Meier method. Prognostic factors were assessed via univariate analysis and multivariate logistic regression. Favorable outcome was defined as a score of 0–4 on the modified Rankin Scale.

RESULTS

Multivariate logistic regression revealed that anisocoria, diagnosis, and ICP values differed significantly between the outcome groups. ICP values in the favorable and unfavorable outcome groups differed significantly (p < 0.001), while the mean ICP of both groups lay below the limit of 20 mm Hg (17.5 and 11.5 mm Hg, respectively). These findings were reproduced when analyzing the underlying pathologies of TBI and MCA infarction separately. Based on these findings, optimized time-dependent threshold values were calculated and found to be between 10 and 17 mm Hg. These values significantly distinguished favorable from unfavorable outcome and predicted 30-day mortality (p < 0.001).

CONCLUSIONS

This study systematically evaluated ICP levels in a long-term analysis after DC and provides new, surprisingly low, time-dependent ICP thresholds for these patients. Future trials investigating the benefit of ICP-guided therapy should take these thresholds into consideration and validate them in further patient cohorts.

Speckle Tracking in Transcranial Ultrasound Allows Noninvasive Analysis of Pulsation Patterns of the Third Ventricle

Cerebrospinal fluid (CSF) flow is sensitive to many cerebral disorders. We aimed to develop a noninvasive bedside method to detect physiological and pathological CSF phenomena by measuring pulsation patterns of the third ventricle. By transcranial B-mode ultrasound, electrocardiography (ECG)-gated video loops of the third ventricle were acquired. "Speckle tracking" software was used to quantify the relative change of its width. We conducted measurements of nine cardiac cycles in 11 healthy subjects in sitting and in supine position during Valsalva maneuver to investigate the influence of an increased intracranial pressure on the relative deformation of the third ventricle. In one patient with occlusive hydrocephalus, 19 cardiac cycles were measured in sitting position before and after removal of a tumorous obstruction of the aqueduct of Sylvius. Healthy subjects expressed a pulse-related increased width of the third ventricle ([Formula: see text]: +5.69, 95% confidence interval [CI] = [4.38, 7.00]). No significant difference was found between the sitting and the supine position in healthy adults. In the preoperative state of occlusive hydrocephalus, we found a negative, pulse-related deformation ([Formula: see text]: -1.86, 95% CI = [-2.15, -1.58]) with delayed onset. After surgery, the deformation pattern resembled that of our healthy controls. The difference between pre- and postoperative condition was significant (p < 0.001). Transcranial B-mode sonography can be used to record small movements of the sidewalls of the third ventricle. This noninvasive bedside method is suitable to assess CSF pulsatility within the third ventricle and might be able to distinguish between physiological and pathological flows.

Safety and Efficacy of Hypothermia (34°C) after Hemicraniectomy for Malignant MCA Infarction

OBJECTIVE

The beneficial effect of hypothermia after hemicraniectomy in malignant middle cerebral artery (MCA) infarction has been controversial. We aim to investigate the safety and clinical efficacy of hypothermia after hemicraniectomy in malignant MCA infarction.

METHODS

From October 2012 to February 2016, 20 patients underwent hypothermia (Blanketrol III, Cincinnati Sub-Zero, Cincinnati, OH, USA) at 34°C after hemicraniectomy in malignant MCA infarction (hypothermia group). The indication of hypothermia included acute cerebral infarction >2/3 of MCA territory and a Glasgow coma scale (GCS) score <11 with a midline shift >10 mm or transtentorial herniation sign (a fixed and dilated pupil). We retrospectively collected 27 patients, as the control group, who had undergone hemicraniectomy alone and simultaneously met the inclusion criteria of hypothermia between January 2010 and September 2012, before hypothermia was implemented as a treatment strategy in Dong-A University Hospital. We compared the mortality rate between the two groups and investigated hypothermia-related complications, such as postoperative bleeding, pneumonia, sepsis and arrhythmia.

RESULTS

The age, preoperative infarct volume, GCS score, National institutes of Health Stroke Scale score, and degree of midline shift were not significantly different between the two groups. Of the 20 patients in the hypothermia group, 11 patients were induced with hypothermia immediately after hemicraniectomy and hypothermia was initiated in 9 patients after the decision of hypothermia during postoperative care. The duration of hypothermia was 4±2 days (range, 1 to 7 days). The side effects of hypothermia included two patients with arrhythmia, one with sepsis, one with pneumonia, and one with hypotension. Three cases of hypothermia were discontinued due to these side effects (one sepsis, one hypotension, and one bradycardia). The mortality rate of the hypothermia group was 15.0% and that of the control group was 40.7% (p=0.056). On the basis of the logistic regression analysis, hypothermia was considered to contribute to the decrease in mortality rate (odds ratio, 6.21; 95% confidence interval, 1.04 to 37.05; p=0.045).

CONCLUSION

This study suggests that hypothermia after hemicraniectomy is a viable option when the progression of patients with malignant MCA infarction indicate poor prognosis.

Brainstem Monitoring in the Neurocritical Care Unit: A Rationale for Real-Time, Automated Neurophysiological Monitoring

Patients with severe traumatic brain injury or large intracranial space-occupying lesions (spontaneous cerebral hemorrhage, infarction, or tumor) commonly present to the neurocritical care unit with an altered mental status. Many experience progressive stupor and coma from mass effects and transtentorial brain herniation compromising the ascending arousal (reticular activating) system. Yet, little progress has been made in the practicality of bedside, noninvasive, real-time, automated, neurophysiological brainstem, or cerebral hemispheric monitoring. In this critical review, we discuss the ascending arousal system, brain herniation, and shortcomings of our current management including the neurological exam, intracranial pressure monitoring, and neuroimaging. We present a rationale for the development of nurse-friendly-continuous, automated, and alarmed-evoked potential monitoring, based upon the clinical and experimental literature, advances in the prognostication of cerebral anoxia, and intraoperative neurophysiological monitoring.

Challenges in the Anesthetic and Intensive Care Management of Acute Ischemic Stroke

Acute ischemic stroke (AIS) is a devastating condition with high morbidity and mortality. In the past 2 decades, the treatment of AIS has been revolutionized by the introduction of several interventions supported by class I evidence-care on a stroke unit, intravenous tissue plasminogen activator within 4.5 hours of stroke onset, aspirin commenced within 48 hours of stroke onset, and decompressive craniectomy for supratentorial malignant hemispheric cerebral infarction. There is new class I evidence also demonstrating benefits of endovascular therapy on functional outcomes in those with anterior circulation stroke. In addition, the importance of the careful management of key systemic physiological variables, including oxygenation, blood pressure, temperature, and serum glucose, has been appreciated. In line with this, the role of anesthesiologists and intensivists in managing AIS has increased. This review highlights the main challenges in the endovascular and intensive care management of AIS that, in part, result from the paucity of research focused on these areas. It also provides guidelines for the management of AIS based upon current evidence, and identifies areas for further research.

Clinical and Radiological Predictors of Malignant Middle Cerebral Artery Infarction Development and Outcomes

BACKGROUND

Optic nerve sheath diameter (ONSD) can predict intracranial hypertension and outcomes in severe traumatic brain injury. Its utility in middle cerebral artery (MCA) stroke is unknown.

AIMS

We reviewed serial radiological measurements, including ONSD, in patients with MCA stroke undergoing decompressive craniectomy (DC) for malignant MCA syndrome and compared demographic, clinical, and radiological data with an age- and gender-matched group of nonmalignant MCA stroke patients.

METHODS

Patients admitted to a large tertiary hospital in London, UK, between April 2012 and October 2016 with MCA infarction were identified through 2 data sources. We quantified ONSD, eyeball transverse diameter (ETD), ONSD/ETD ratio, midline shift (MLS), and infarct volume on computed tomography (CT).

RESULTS

We identified 19 patients (mean age = 49.8 years [standard deviation = 12.5]) with malignant MCA stroke and 19 patients (47.8 years [16.0]) with nonmalignant MCA stroke. Mean ONSD, ONSD/ETD ratio, MLS, and infarct volume on initial CT all significantly increased after developing malignant MCA syndrome and decreased (except infarct volume, which increased) following DC (all Ps <.05). ONSD and ONSD/ETD ratios in the malignant group did not correlate with functional outcomes but were significantly higher on initial CT compared with the nonmalignant group (mean ONSD: 5.66 mm [.6] versus 4.97 mm [.5], P = .001; mean ONSD/ETD ratio: .25 [.03] versus .22 [.02], P = .002).

CONCLUSIONS

ONSD, ONSD/ETD ratio, MLS, and infarct volume change dynamically in patients with malignant MCA infarction who undergo DC. An ONSD of more than 5.25 mm and an ONSD/ETD ratio of more than .232 on initial CT may identify MCA stroke patients at high risk of developing malignant MCA syndrome.

No benefits of hypothermia in patients treated with hemicraniectomy for large ischemic stroke

Background Space-occupying middle cerebral artery brain infarcts are associated with the development of brain edema, which may lead to cerebral herniation and death despite early hemicraniectomy. Aims To evaluate the benefit of therapeutic hypothermia in patients with space-occupying cerebral infarction treated with hemicraniectomy within 48 h of stroke onset. Methods Patients aged 18-60 years with space-occupying cerebral infarction treated with hemicraniectomy within 48 h and hypothermia (33-34°C) were selected from a single university hospital between 2001 and 2010 (n = 53). Patients treated with hemicraniectomy alone served as comparison group (n = 58), originating from three randomized controlled trials evaluating the effects of early decompressive surgery (DECIMAL, DESTINY, HAMLET). Primary outcome was the score on the modified Rankin scale at 12 months dichotomized between modified Rankin scale 0-3 and modified Rankin scale 4-6. Secondary outcome measures were modified Rankin scale score 0-4 and survival. Risk ratios were adjusted with Poisson regression. Results Mean patient age was 48 years. Median time from stroke onset to hemicraniectomy was 23.5 h in both treatment groups. Treatment with hypothermia had no effect on the primary outcome (modified Rankin scale 0-3 versus 4-6 (13/53 (25%) versus 24/58 (41%)); adjusted risk ratio 0.66, 95% confidence interval 0.38-1.13). Fewer patients treated with hypothermia had a modified Rankin scale score of 0-4 (21/53 (40%) versus 42/58 (72%); adjusted risk ratio 0.53, 95% confidence interval 0.37-0.76) and fewer patients survived (26/53 (49%) versus 46/58 (79%); adjusted risk ratio 0.60, 95% confidence interval 0.44-0.82). Conclusions In patients with space-occupying cerebral infarction, treatment with hypothermia had no additional benefit on functional outcome compared with treatment with hemicraniectomy alone.

Evidence-based guidelines for the management of large hemispheric infarction : a statement for health care professionals from the Neurocritical Care Society and the German Society for Neuro-intensive Care and Emergency Medicine

Large hemispheric infarction (LHI), also known as malignant middle cerebral infarction, is a devastating disease associated with significant disability and mortality. Clinicians and family members are often faced with a paucity of high quality clinical data as they attempt to determine the most appropriate course of treatment for patients with LHI, and current stroke guidelines do not provide a detailed approach regarding the day-to-day management of these complicated patients. To address this need, the Neurocritical Care Society organized an international multidisciplinary consensus conference on the critical care management of LHI. Experts from neurocritical care, neurosurgery, neurology, interventional neuroradiology, and neuroanesthesiology from Europe and North America were recruited based on their publications and expertise. The panel devised a series of clinical questions related to LHI, and assessed the quality of data related to these questions using the Grading of Recommendation Assessment, Development and Evaluation guideline system. They then developed recommendations (denoted as strong or weak) based on the quality of the evidence, as well as the balance of benefits and harms of the studied interventions, the values and preferences of patients, and resource considerations.

Hemispheric differences in malignant middle cerebral artery stroke

BACKGROUND

We recently reported that left versus right hemisphere cerebral infarctions patients more frequently have worse outcomes. However our clinical experience led us to suspect that the incidence of malignant middle cerebral artery infarctions (MMCA) was higher in the right compared to the left hemispheric strokes.

OBJECTIVE

To determine whether laterality in MMCA stroke is an important determinant of stroke sequelae.

METHODS

A systematic search was performed for publications in PubMed using "malignant middle cerebral artery and infarction". A total of 73 relevant studies were abstracted.

RESULTS

MMCA laterality data were available for 2673 patients, with 1687 (63%) right hemispheric involvement, thus right being more commonly associated with MMCA (binomial test, p<0.05). While mortality rates were similar, right hemispheric MMCA (n=271) had mortality of 31% (n=85) whereas left hemispheric MMCA (n=144) had mortality of 36% (n=53), morbidity rates were worse on the right.

CONCLUSION

MMCA stroke appears to be more common on the right, and this laterality is also associated with significantly higher morbidity. Further prospective studies are needed to more completely understand the nature of this laterality as well as test possible new treatments to reduce mortality and morbidity associated with MMCA.

Emergency and critical care management of acute ischaemic stroke

Ischaemic stroke is a devastating condition that is the leading cause of disability in the USA. Over the last 2 decades, the focus of management has shifted from secondary stroke prevention to acute treatment. Coordinated care starts in the field with the emergency medical service providers and continues in the ambulance and the emergency department through to the intensive care unit. After diagnosis and stabilization, a major goal is reperfusion therapy with intravenous fibrinolytics. Neuroimaging research is focused on improving patient selection, expanding treatment windows, and increasing the safety of therapeutic intervention. The role of adjunctive intra-arterial and mechanical thrombectomy remains undefined, and methods to improve reperfusion using sonolysis and new-generation fibrinolytics are currently investigational. Treatment in the intensive care unit targets prevention of secondary brain injury through optimization of blood pressure, cerebral perfusion, glucose, and temperature management, ventilation, and oxygenation. The most feared complications include malignant cerebral edema and symptomatic hemorrhagic transformation. Decompressive craniectomy is life saving, but questions regarding patient selection and timing remain. Hyperosmolar agents are currently used to mitigate cerebral edema, but newer agents to prevent the formation of cerebral edema at the molecular level are being studied. We outline a practical approach to current emergency and intensive care management based on consensus guidelines and the best available evidence.

Middle cerebral arterial flow changes on transcranial color and spectral Doppler sonography in patients with increased intracranial pressure

OBJECTIVES

Intracranial pressure usually increases after severe brain injury. However, a method for noninvasive evaluation of intracranial pressure is still lacking. The purpose of this study was to explore the potential role of transcranial color Doppler sonography in assessing intracranial pressure by observing the middle cerebral artery blood flow parameters in patients with increased intracranial pressure of varying etiology.

METHODS

The hemodynamic changes in the middle cerebral artery in patients with varying degrees of increased intracranial pressure were investigated by transcranial color Doppler sonography in 93 patients who had emergency surgery for brain injury.

RESULTS

Middle cerebral artery Doppler flow spectra changed regularly as intracranial pressure increased. The pulsatility index (PI) and resistive index (RI) had a significantly positive correlation with intracranial pressure (r = 0.90 and 0.89, respectively; P< .001), whereas the middle cerebral artery diastolic velocity showed a significant negative correlation with intracranial pressure (r = -0.52; P< .01). A receiver operating characteristic curve showed that the RI and PI cutoff values were 0.705 and 1.335, respectively, for predicting increased intracranial pressure, with sensitivity of 0.885 and specificity of 0.970.

CONCLUSIONS

In addition to the PI and RI, middle cerebral artery diastolic flow velocity measurement by transcranial color Doppler sonography may also be a useful variable for evaluating intracranial pressure in patients with acute brain injury.

Treatment of malignant brain edema and increased intracranial pressure after stroke

OPINION STATEMENT

The management of patients with large territory ischemic strokes and the subsequent development of malignant brain edema and increased intracranial pressure is a significant challenge in modern neurology and neurocritical care. These patients are at high risk of subsequent neurologic decline and are best cared for in an intensive care unit or a comprehensive stroke center with access to neurosurgical support. Risks include hemorrhagic conversion, herniation, poor functional outcome, and death. This review discusses recent advances in understanding the pathophysiology of edema formation, identifying patients at risk, current management strategies, and emerging therapies.

Critical care for patients with massive ischemic stroke

Malignant cerebral edema following ischemic stroke is life threatening, as it can cause inadequate blood flow and perfusion leading to irreversible tissue hypoxia and metabolic crisis. Increased intracranial pressure and brain shift can cause herniation syndrome and finally brain death. Multiple randomized clinical trials have shown that preemptive decompressive hemicraniectomy effectively reduces mortality and morbidity in patients with malignant middle cerebral artery infarction. Another life-saving decompressive surgery is suboccipital craniectomy for patients with brainstem compression by edematous cerebellar infarction. In addition to decompressive surgery, cerebrospinal fluid drainage by ventriculostomy should be considered for patients with acute hydrocephalus following stroke. Medical treatment begins with sedation, analgesia, and general measures including ventilatory support, head elevation, maintaining a neutral neck position, and avoiding conditions associated with intracranial hypertension. Optimization of cerebral perfusion pressure and reduction of intracranial pressure should always be pursued simultaneously. Osmotherapy with mannitol is the standard treatment for intracranial hypertension, but hypertonic saline is also an effective alternative. Therapeutic hypothermia may also be considered for treatment of brain edema and intracranial hypertension, but its neuroprotective effects have not been demonstrated in stroke. Barbiturate coma therapy has been used to reduce metabolic demand, but has become less popular because of its systemic adverse effects. Furthermore, general medical care is critical because of the complex interactions between the brain and other organ systems. Some challenging aspects of critical care, including ventilator support, sedation and analgesia, and performing neurological examinations in the setting of a minimal stimulation protocol, are addressed in this review.

Hemicraniectomy for malignant middle cerebral artery infarction: current status and future directions

Malignant middle cerebral artery infarction is a life-threatening sub-type of ischemic stroke that may only be survived at the expense of permanent disability. Decompressive hemicraniectomy is an effective surgical therapy to reduce mortality and improve functional outcome without promoting most severe disability. Evidence derives from three European randomized controlled trials in patients up to 60 years. The recently finished DEcompressive Surgery for the Treatment of malignant INfarction of the middle cerebral arterY - II trial gives now high-level evidence for the effectiveness of decompressive hemicraniectomy in patients older than 60 years. Nevertheless, pressing issues persist that need to be answered in future clinical trials, e.g. the acceptable degree of disability in survivors of malignant middle cerebral artery infarction, the importance of aphasia, and the best timing for decompressive hemicraniectomy. This review provides an overview of the current diagnosis and treatment of malignant middle cerebral artery infarction with a focus on decompressive hemicraniectomy and outlines future perspectives.