Management of delayed cerebral ischemia after subarachnoid hemorrhage

Emerging Advances in the Management of Delayed Cerebral Ischemia After Aneurysmal Subarachnoid Hemorrhage: A Narrative Review

Background/Objectives: Aneurysmal subarachnoid hemorrhage (aSAH) remains a life-threatening cerebrovascular event with high rates of mortality and long-term morbidity. Among its complications, delayed cerebral ischemia (DCI) is a major contributor to poor clinical outcomes. Although cerebral vasospasm has traditionally been considered the primary mechanism underlying DCI, recent studies have revealed the multifactorial nature of this condition. This review aims to provide a comprehensive overview of the pathophysiology, preventive strategies, and current treatment options for DCI following aSAH. Methods: A narrative literature review was conducted using the PubMed database to identify peer-reviewed articles relevant to the prevention and treatment of DCI following aSAH. The search strategy employed the following terms: ("Subarachnoid Hemorrhage" [MeSH]) AND "Delayed Cerebral Ischemia" AND ("Prevention and Control" [Subheading] OR "Secondary Prevention" [MeSH]). This search strategy was designed to capture studies addressing both pharmacological and non-pharmacological preventive measures for DCI. Results: A comprehensive PubMed search identified a total of 113 relevant articles. Among these, 40 publications primarily addressed pharmacological interventions, while 22 focused on neuromonitoring techniques. An additional 20 articles explored the pathophysiological mechanisms underlying DCI, and 15 involved preclinical studies utilizing animal models. The remaining 16 articles encompassed diverse topics, including prophylactic endovascular therapies, newly proposed definitions of DCI, treatment algorithm development, functional outcome analyses, and entries in clinical trial registries. Emerging evidence highlights that vasospasm alone does not account for all cases of DCI. Pharmacological approaches such as nimodipine, clazosentan, and fasudil have shown varying degrees of efficacy. Circulatory management and removal of subarachnoid hematoma via CSF drainage or thrombolytics may reduce DCI risk, although their impact on long-term neurological outcomes remains controversial. Endovascular therapy and adjunctive agents such as cilostazol or anticoagulants have demonstrated potential but require further validation through large-scale trials. Conclusions: Effective DCI prevention and treatment require a multimodal approach targeting diverse pathological mechanisms beyond vasospasm. Improved risk stratification, early detection, and individualized therapy are essential for advancing the management of patients with aSAH.

Functional outcomes following endovascular treatment of vasospasm secondary to aneurysmal subarachnoid Hemorrhage: A Single center retrospective analysis

INTRODUCTION

Endovascular treatment of post-hemorrhagic cerebral vasospasm (PHCV) has the potential to improve functional outcomes but there continues to be limited data reported in the literature.

OBJECTIVE

To retrospectively review our institution's experience treating PHCV endovascularly and report clinical outcome data.

METHODS

Patients who experienced nontraumatic subarachnoid hemorrhage (SAH) and were treated with endovascular therapy were identified using ICD and CPT codes. Demographic, clinical, and outcome variables were then collected via review of electronic medical records. The primary outcome measure was rate of modified Rankin Score (mRS) ≤ 2 at discharge as well as 1, 3, and 6 months after discharge. Discharge disposition, angiographic response to treatment, and complication rates were secondary outcomes. A subgroup analysis was performed on patients treated with retrievable stents.

RESULTS

In a 12.5 year period, 1396 patients with nontraumatic SAH were treated, and of these 82/1396 (5.9 %) were treated endovascularly for vasospasm. 200 total interventions were performed on 82 patients. 29.7 % of patients had radiographic delayed cerebral ischemia. The complication rates were 3.5 % per procedure and 4.9 % per patient. 40.7 % of patients had good neurologic outcomes (mRS ≤ 2) at any time point. In-hospital mortality was 11 % and 6-month mortality was 21 %. Higher presenting Glasgow Coma Score (GCS) predicted good neurologic outcome in univariable logistic regression (OR = 1.33, p = 0.026). Patients that underwent mechanical angioplasty were significantly younger than those who did not (46 years vs 53 years, p = 0.003). 11 cases of retrievable stent angioplasty were performed, yielding a complication rate of 9 % which was comparable to the complication rate of patients treated with balloon angioplasty (4.3 %, p = 0.54).

CONCLUSIONS

Our experience with endovascular treatment of PHCV results in similar functional outcomes and complication rates to the literature. Better presenting GCS predicts good functional outcomes in patients with PHCV treated endovascularly. Patients undergoing mechanical angioplasty tended to be younger. Retrievable stents produced similar rates of complications and good functional outcomes to balloon angioplasty patients.

Grading Scores for Identifying Patients at Risk of Delayed Cerebral Ischemia and Neurological Outcome in Spontaneous Subarachnoid Hemorrhage: A Comparison of Receiver Operator Curve Analysis

BACKGROUND

Numerous grading scales were proposed for subarachnoid hemorrhage (SAH) to assess the likelihood of unfavorable neurological outcomes (UO) and the risk of delayed cerebral ischemia (DCI). We aimed to validate the Hemorrhage, Age, Treatment, Clinical Status, and Hydrocephalus (HATCH) score and the VASOGRADE, a simple grading scale for prediction of DCI after aneurysmal SAH.

METHODS

This was a retrospective single-center study of patients with nontraumatic SAH (January 2016 to December 2021) admitted to the intensive care unit. We performed a receiver operating characteristic (ROC) curve analysis to assess the discriminative ability of the HATCH and the VASOGRADE to identify patients who had UO at 3 months (defined as Glasgow Outcome Scale score of 1-3), hospital mortality, and DCI and compared their performance with the World Federation of Neurosurgical Surgeons, the modified Fisher, the Sequential Organ Failure Assessment, and the Acute Physiology and Chronic Health Evaluation II scales. We performed a multivariate logistic regression analysis to assess the association between HATCH and UO at 3 months and between VASOGRADE and DCI.

RESULTS

We included 262 consecutive patients with nontraumatic SAH. DCI was observed in 82 patients (31.3%), whereas 78 patients (29.8%) died during hospital stay and 133 patients (51%) had UO at 3 months. HATCH was independently associated with UO (odds ratio 1.61, 95% confidence interval [CI] 1.36-1.90) and had an area under the ROC curve (AUROC) of 0.83 (95% CI 0.77-0.88), comparable to the Acute Physiology and Chronic Health Evaluation II (AUROC 0.84, 95% CI 0.79-0.89) and Sequential Organ Failure Assessment (AUROC 0.83, 95% CI 0.77-0.88).

CONCLUSIONS

Hemorrhage, Age, Treatment, Clinical Status, and Hydrocephalus and VASOGARDE scores had a good performance to predict UO or in-hospital mortality and DCI, respectively; however, their performance did not outperform nonspecific routinely used scores.

Acute Neurovascular Inflammatory Profile in Patients with Aneurysmal Subarachnoid Hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) is a life-threatening condition that results from intracranial aneurysm rupture, leading to the accumulation of blood between the arachnoid and pia mater. The blood breakdown products and damage-associated molecule patterns (DAMPs), which are released as a result of vascular and cellular compromise following aneurysm rupture, elicit local endothelial reactions leading to the narrowing of cerebral arteries and ischemia. In addition, vascular inflammation, characterized by activated endothelial cells, perpetuates disruption of the neurovascular unit and the blood-brain barrier. The uncertain prognosis of aSAH patients contributes to the necessity of a fluid biomarker that can serve as a valuable adjunct to radiological and clinical evaluation. Limited studies have investigated vascular inflammation and angiogenic protein expression following aSAH. Reliable markers of the vascular inflammatory and angiogenic response associated with aSAH may allow for the earlier detection of patients at risk for complications and aid in the identification of novel pharmacologic targets. We investigated whether vascular inflammatory and angiogenesis signaling proteins may serve as potential biomarkers of aSAH. Serum and cerebrospinal fluid (CSF) from fifteen aSAH subjects and healthy age-matched controls as well as hydrocephalus (CSF) no-aneurysm controls were evaluated for levels of vascular inflammatory and angiogenesis proteins. Protein measurement was carried out using electrochemiluminescence. The area under the curve (AUC) was calculated using receiver operating characteristics (ROC) to obtain information on biomarker reliability, specificity, sensitivity, cut-off points, and likelihood ratio. In addition, patients were grouped by Glasgow Outcome Score-Extended at 3 months post-injury to determine the correlation between vascular inflammatory protein levels and clinical outcome measures. aSAH subjects demonstrated elevated vascular inflammatory protein levels in serum and CSF when compared to controls. Certain vascular injury and angiogenic proteins were found to be promising biomarkers of inflammatory response in aSAH in the CSF and serum. In particular, elevated levels of serum amyloid-alpha (SAA) were found to be correlated with unfavorable outcomes following aSAH. Determination of these protein levels in CSF and serum in aSAH may be utilized as reliable biomarkers of inflammation in aSAH and used clinically to monitor patient outcomes.

Prognostic factors in aneurysmal subarachnoid hemorrhage with poor initial clinical grade

Introduction

Aneurysmal subarachnoid hemorrhage (aSAH) is a rare cause of stroke that poses significant morbidity and mortality, as it affects patients around the age of 50 years. While advances in early aneurysm intervention have reduced mortality rates, many patients still experience poor outcomes due to early brain injury (EBI) and delayed cerebral ischemia (DCI). This study aims to explore the characteristics of patients with poor neurological outcomes among patients with poor neurological status at admission, using comprehensive clinical and neuroimaging data.

Methods

We analyzed 377 aSAH patients (WFNS 4-5) admitted between 2013 and 2020, focusing on demographics, clinical assessments, imaging, treatments, and outcomes at discharge and 3 months later.

Results

Among the cohort, which predominantly consisted of females, the mortality rate was 49%. Our findings indicate that older patients had poorer functional outcomes; notably, 59% of patients aged 75 and older had limitations on therapeutic efforts, leading to a 100% mortality rate in that subgroup. There was no difference in outcomes between endovascular and surgical treatments. However, patients undergoing multimodal monitoring had better functional outcomes at discharge. Angiographic vasospasm was found in 31% of patients and was linked to poorer outcomes at discharge (p = 0.016). Though DCI did not directly correlate with functional outcomes, it correlated strongly with new cerebral infarcts (90% incidence).

Conclusion

The prognosis of patients with aSAH and poor neurological status on admission is generally poor. Multimodal monitoring and tailored treatment appear to be beneficial in achieving favorable results in these patients. Despite the initial severity, up to 20% of patients achieve a good functional result on discharge and up to 35% do so at 3 months. These should be considered in the initial prognostic assessment with the families of these patients.

MiR-34c Is Predictive of Delayed Cerebral Ischemia After Subarachnoid Hemorrhage

Introduction Delayed cerebral ischemia (DCI) is a potentially preventable complication from an aneurysmal subarachnoid hemorrhage (SAH). The micro-RNAs (miR) 34 family has shown its ability to disrupt the blood-brain barrier and redox metabolism and might contribute to the complex pathophysiology of DCI. This study aimsto evaluate the association between the serum levels of miR-34c and the occurrence of DCI. Methods This retrospective observational study is based on 72 subjects with acute aneurysmal SAH who were admitted to a single tertiary center between December 2017 and July 2021. Subjects were prospectively adjudicated for clinical outcomes, including delayed cerebral ischemia.Levels of miR-34c were measured in plasma collected within 48 hours of ictus. Patients were median-dichotomized into having a higher or lower plasma level of miR-34c. miR34c levels were compared between DCI and no DCI groups using the Wilcoxon rank sum tests. A multivariable logistic regression model and the Cox proportional hazard model were used to evaluate the effect of higher miR-34c levels. Results The median age was 54 years, 76% were females, and 21% developed DCI. Early miR-34c levels were significantly higher in SAH subjects who progressed to have DCI with Cohen's d of 0.75 (p<0.05). Even after adjusting for age, sex, histories of diabetes, hypertension, Hunt-Hess grade, and modified Graeb scores, a higher miR-34c level was associated with 5.7-fold increased odds of DCI (p<0.05; 95% CI: 1.35-32.22). Survival analysis adjusting for the known predictors also revealeda 5.4-fold higher hazard of DCI for the patients with a higher miR-34c level (p < 0.05; 95% CI 1.22-25.43). Conclusion The present study demonstrates the potential importance of circulating miR-34c in predicting DCI in SAH patients. Given the known importance of the miR-34 family in vascular physiology, it may be an important target for future studies.

Long-Term Cognitive Decline After Subarachnoid Hemorrhage: Pathophysiology, Management, and Future Directions

Subarachnoid hemorrhage is a critical neurological condition accounting for about 5% of all strokes, and survivors experience long-term cognitive deterioration and increased risk of dementia. The major processes involved in such decline include early brain injury, delayed cerebral ischemia, neuroinflammation, superficial siderosis, and hydrocephalus. These have emerging treatments that offer promise for the mitigation of effects such as inflammation, iron chelation, and microvascular dysfunction. Genetic predispositions have been associated with post-subarachnoid hemorrhage cognitive outcomes and emphasize a role for personalized care strategies. Management techniques reviewed include long-term cognitive health, such as endovascular coiling and surgical clipping. Other rehabilitation strategies that enhance cognitive reserve and pharmacological interventions are discussed about improving the quality of life in survivors. The review highlights the need for further research into targeted therapies, genetic markers, and innovative approaches to prevent cognitive decline, ultimately aiming to optimize long-term outcomes for individuals affected by subarachnoid hemorrhage.

Predictive modeling of aneurysmal subarachnoid hemorrhage with acute lung injury complicating delayed cerebral ischaemia

Objective

Delayed cerebral ischemia (DCI) is a frequent consequence of aneurysmal subarachnoid hemorrhage (aSAH), and severe aSAH is typically accompanied with Acute Lung Injury (ALI). This research examined the risk variables for delayed cerebral ischaemia in aneurysmal subarachnoid hemorrhage patients complicated with ALI, and developed a columnar graph prediction model.

Methods

Clinical data from 234 patients with aSAH complicated with ALI, admitted to Lishui People's Hospital between January 2018 and June 2024, were analyzed. The patients were randomly divided into a training group (164 cases) and a validation group (70 cases). Risk factors for the occurrence of delayed cerebral ischaemia (DCI) were identified and incorporated into a model, the differentiation and reliability of the line graph model were validated via the use of ROC curves and calibration curves.

Results

Multifactorial logistic regression identified three significant independent risk variables for DCI: elevated positive end-expiratory pressure (PEEP), interleukin-6, and D-dimer (p < 0.05). The column-line plots demonstrated superior discriminatory performance in both the training set (AUC = 0.882, 95% CI: 0.820-0.940) and the validation set (AUC = 0.874, 95% CI: 0.778-0.996), while the calibration curves indicated strong concordance between the training and validation sets.

Conclusion

High positive end-expiratory pressure, interleukin-6, and d-dimer are independent risk factors for DCI in patients with aSHA combined with ALI, and the resulting columnar line graphs show significant predictive value and help to better identify patients at high risk of DCI.

The role of Glucose/Potassium Ratio and Neutrophil/Lymphocyte Ratio in the prognosis of patients with aneurysmal subarachnoid hemorrhage

ANTECEDENTS AND OBJECTIVE

Aneurysmal subarachnoid hemorrhage (aSAH) is associated with high morbidity and mortality. Traditional factors strongly associated with poor outcome are neurological condition and the amount of bleeding. Inflammation is considered a relevant mechanism of brain injury after aSAH. This study aims to investigate the potential role of new laboratory indexes related to inflammation for predicting the prognosis of aSAH patients, complementing established prognostic models.

MATERIALS AND METHODS

We conducted a retrospective observational study including adults admitted for aSAH at a single neurosurgery center from 2002 to 2023. Demographic data, clinical parameters, and blood test results at admission were collected. The main outcome variable was Glasgow Outcome Scale (GOS) six month post-bleeding. A second outcome variable was in-hospital mortality. Univariable analyses were performed to identify new laboratory predictors of poor prognosis. The independent association with outcome was evaluated after adjustment of traditional risk factors by logistic regression analysis. The additional value of new laboratory predictors was determined by comparison of the area under the receiver operating curve (AUROC).

RESULTS

Among 542 patients with aSAH, 417 met inclusion criteria (age >18 years old and complete laboratory test available upon admission with aSAH confirmed by CT angiography (CTA) or digital subtraction angiography (DSA)). Elevated glucose/potassium ratio (GKR) in the first blood test at admission was significantly associated with unfavorable outcome and in-hospital mortality according to univariate analysis. The GKR was significantly associated with a worse final prognosis (OR 1.033, 95% CI 1.008-1.040) adjusted for age, WFNS and Fisher scales, history of diabetes mellitus and kidney disease, and prior use of diuretics, oral antidiabetic medications and insulin. Additionally, the inclusion of the GKR improved the predictive accuracy of a prognostic model compared to a model including only clinical and radiological data. The neutrophil-lymphocyte ratio (NLR) was not significantly different between subgroups of patients regarding their outcome.

CONCLUSION

GKR measured in the first 24 h after aSAH may improve the discrimination of patients with higher risk of experiencing poor outcome at six month after the bleeding.

Evidence-Based Approach to Cerebral Vasospasm and Delayed Cerebral Ischemia: Milrinone as a Therapeutic Option-A Narrative Literature Review and Algorithm Treatment Proposition

Aneurysmal subarachnoid hemorrhage (aSAH) is a severe neurocritical condition often complicated by cerebral vasospasm (CVS), leading to delayed cerebral ischemia (DCI) and significant morbidity and mortality. Despite advancements in management, therapeutic options with robust evidence remain limited. Milrinone, a phosphodiesterase type 3 (PDE3) inhibitor, has emerged as a potential therapeutic option. Intravenous milrinone demonstrated clinical and angiographic improvement in 67% of patients, reducing the need for mechanical angioplasty and the risk of functional disability at 6 months (mRS ≤ 2). Side effects, including hypotension, tachycardia, and electrolyte disturbances, were observed in 33% of patients, occasionally leading to early drug discontinuation. Based on the evidence, we propose a treatment algorithm for using milrinone to optimize outcomes and standardize its application in neurocritical care settings.

Liberal versus restrictive transfusion strategies in subarachnoid hemorrhage: a secondary analysis of the TRAIN study

BACKGROUND

The optimal hemoglobin (Hb) threshold to trigger red blood cell transfusions (RBCT) in subarachnoid hemorrhage (SAH) patients is unclear. This study evaluated the impact of liberal versus restrictive transfusion strategies on neurological outcome in patients with SAH.

METHODS

This is a pre-planned secondary analysis of the "TRansfusion Strategies in Acute brain INjured Patients" (TRAIN) study. We included all SAH patients from the original study that were randomized to receive RBCT when Hb levels dropped below 9 g/dL (liberal group) or 7 g/dL (restrictive group). The primary outcome was an unfavorable neurological outcome at 180 days, defined by a Glasgow Outcome Scale Extended score of 1-5.

RESULTS

Of the 190 SAH patients in the trial, 188 (98.9%) had data available for the primary outcome, with 86 (45.3%) in the liberal group and 102 (53.6%) in the restrictive group. Patients in the liberal group were older than in the restrictive group, but otherwise had similar baseline characteristics. Patients in the liberal group received more RBCT and showed higher Hb levels over time. At 180 days, 57 (66.3%) patients in the liberal group and 78 (76.4%) in the restrictive group had unfavorable outcomes (risk ratio, RR 0.87; 95% confidence intervals, 95% CI 0.71-1.04). Patients in the liberal group had a significantly lower risk of cerebral ischemia (RR 0.63; 95% CI 0.41-0.97). In a multivariate analysis, randomization to the liberal group was associated with a lower risk of unfavorable outcome (RR 0.83, 95% CI 0.70-0.99).

CONCLUSIONS

A liberal transfusion strategy was not associated with a lower incidence of unfavorable outcome after SAH when compared to a restrictive strategy. However, in a multivariable analysis adjusted for confounders randomization to the liberal group was associated with lower risk of unfavorable outcome. The occurrence of cerebral ischemia was significantly lower in the liberal transfusion strategy group.

TRIAL REGISTRATION

ClinicalTrials.gov number-NCT02968654 registered on November 16th, 2016.

Three Pillars of Recovery After Aneurysmal Subarachnoid Hemorrhage: A Narrative Review

Aneurysmal subarachnoid hemorrhage (aSAH) is a devastating neurologic disease with high mortality and disability. There have been global improvements in survival, which has contributed to the prevalence of patients living with long-term sequelae related to this disease. The focus of active research has traditionally centered on acute treatment to reduce mortality, but now there is a great need to study the course of short- and long-term recovery in these patients. In this narrative review, we aim to describe the core pillars in the preservation of cerebral function, prevention of complications, the recent literature studying neuroplasticity, and future directions for research to enhance recovery outcomes following aSAH.

Machine Learning for the Early Prediction of Delayed Cerebral Ischemia in Patients With Subarachnoid Hemorrhage: Systematic Review and Meta-Analysis

BACKGROUND

Delayed cerebral ischemia (DCI) is a primary contributor to death after subarachnoid hemorrhage (SAH), with significant incidence. Therefore, early determination of the risk of DCI is an urgent need. Machine learning (ML) has received much attention in clinical practice. Recently, some studies have attempted to apply ML models for early noninvasive prediction of DCI. However, systematic evidence for its predictive accuracy is still lacking.

OBJECTIVE

The aim of this study was to synthesize the prediction accuracy of ML models for DCI to provide evidence for the development or updating of intelligent detection tools.

METHODS

PubMed, Cochrane, Embase, and Web of Science databases were systematically searched up to May 18, 2023. The risk of bias in the included studies was assessed using PROBAST (Prediction Model Risk of Bias Assessment Tool). During the analysis, we discussed the performance of different models in the training and validation sets.

RESULTS

We finally included 48 studies containing 16,294 patients with SAH and 71 ML models with logistic regression as the main model type. In the training set, the pooled concordance index (C index), sensitivity, and specificity of all the models were 0.786 (95% CI 0.737-0.835), 0.77 (95% CI 0.69-0.84), and 0.83 (95% CI 0.75-0.89), respectively, while those of the logistic regression models were 0.770 (95% CI 0.724-0.817), 0.75 (95% CI 0.67-0.82), and 0.71 (95% CI 0.63-0.78), respectively. In the validation set, the pooled C index, sensitivity, and specificity of all the models were 0.767 (95% CI 0.741-0.793), 0.66 (95% CI 0.53-0.77), and 0.78 (95% CI 0.71-0.84), respectively, while those of the logistic regression models were 0.757 (95% CI 0.715-0.800), 0.59 (95% CI 0.57-0.80), and 0.80 (95% CI 0.71-0.87), respectively.

CONCLUSIONS

ML models appear to have relatively desirable power for early noninvasive prediction of DCI after SAH. However, enhancing the prediction sensitivity of these models is challenging. Therefore, efficient, noninvasive, or minimally invasive low-cost predictors should be further explored in future studies to improve the prediction accuracy of ML models.

TRIAL REGISTRATION

PROSPERO (CRD42023438399); https://tinyurl.com/yfuuudde.

Threshold hemoglobin level for delayed cerebral ischemia: A single-center retrospective analysis

Background

Delayed cerebral ischemia (DCI) occurs in approximately 20%-30 % of patients with subarachnoid hemorrhage (SAH). This is the most common complication of SAH and has a high mortality rate. In the present study, we investigated the relationship between hemoglobin (Hb) values and DCI and aimed to determine a cutoff Hb value to be used as a predictor of DCI.

Methods

A total of 259 patients who were followed up for aneurysmal SAH at the Neurosurgery Clinic of Health Sciences University Dışkapı Yıldırım Beyazıt Training and Research Hospital were included in our study. The patients were categorized into three groups according to Hb levels, low: <10 g/dl, moderate:10-13 g/dl, and high: >13 g/dl, and the relationship between Hb value and DCI and clinical outcomes was examined. Further, the cutoff Hb value for predicting DCI was determined by receiver operating characteristics (ROC) curve analysis.

Results

Statistical analyses revealed that patients with low Hb levels of <10 g/dl had a higher frequency of DCI than those with Hb levels of <10.75 g/dl. In addition, pairwise analyses based on the determined cutoff value revealed that patients with Hb levels <10.75 g/dl experienced DCI more frequently.

Conclusion

This study aimed to determine the utility of Hb levels as a predictor of DCI by examining its risk factors. The cutoff Hb level determined here is an important predictive factor for DCI, and the results provide promising evidence in term of early detection of DCI.

Predictors of Neurological Outcomes in Patients with Poor Glasgow Coma Scale Scores 1 Week After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

This study assessed neurological outcomes and variables associated with favorable outcomes in aneurysmal subarachnoid hemorrhage patients with low functional status (Glasgow Coma Scale [GCS] score ≤8) on postbleed day 7 (PBD7).

METHODS

A retrospective analysis was conducted of all patients in the Barrow Ruptured Aneurysm Trial (January 1, 2014-July 31, 2019) treated for a ruptured aneurysm and who had a GCS score ≤8 on PBD7. The primary outcome was a favorable neurological outcome (modified Rankin Scale score ≤2) at last follow-up.

RESULTS

Of 312 patients, 63 had low GCS scores at PBD7. These patients had a significantly greater proportion of poor Hunt and Hess scale grades (≥4) (44/63 [70%] vs. 49/249 [19.7%], P < 0.001) and poor Fisher grades (grade = 4) (58/63 [92%] vs. 174/249 [69.9%], P < 0.001) compared to patients who did not have low GCS scores on PBD7, but no differences were found in age, sex, anterior location, aneurysm size, or type of treatment. Of the 63 patients, 7 (11%) experienced a favorable neurological outcome. On univariate analysis, none of the physical examination reflexes predicted a favorable neurological outcome. The middle cerebral artery aneurysm territory was the only significant predictor of a favorable neurological outcome by multivariate analysis (odds ratio, 10.8; 95% confidence interval, 1.16-100], P = 0.04).

CONCLUSIONS

This study yielded no significant physical examination findings that predict a favorable outcome in patients with a GCS score ≤8 on PBD7. This finding may inform the decision of whether to prolong hospital management or arrange for end-of-life care.

CT perfusion imaging in aneurysmal subarachnoid hemorrhage. State of the art

CT perfusion (CTP) images can be easily and rapidly obtained on all modern CT scanners and have become part of the routine imaging protocol of patients with aneurysmal subarachnoid haemorrhage (aSAH). There is a growing body of evidence supporting the use of CTP imaging in these patients, however, there are significant differences in the software packages and methods of analysing CTP. In. addition, no quantitative threshold values for tissue at risk (TAR) have been validated in this patients' population. Here we discuss the contribution of the technique in the identification of patients at risk of aSAH-related delayed cerebral ischemia (DCI) and in the assessment of the response to endovascular rescue therapy (ERT). We also address the limitations and pitfalls of automated CTP postprocessing that are specific to aSAH patients as compared to acute ischemic stroke (AIS).

The urotensin II receptor triggers an early meningeal response and a delayed macrophage-dependent vasospasm after subarachnoid hemorrhage in male mice

Subarachnoid hemorrhage (SAH) can be associated with neurological deficits and has profound consequences for mortality and morbidity. Cerebral vasospasm (CVS) and delayed cerebral ischemia affect neurological outcomes in SAH patients, but their mechanisms are not fully understood, and effective treatments are limited. Here, we report that urotensin II receptor UT plays a pivotal role in both early events and delayed mechanisms following SAH in male mice. Few days post-SAH, UT expression is triggered by blood or hemoglobin in the leptomeningeal compartment. UT contributes to perimeningeal glia limitans astrocyte reactivity, microvascular alterations and neuroinflammation independent of CNS-associated macrophages (CAMs). Later, CAM-dependent vascular inflammation and subsequent CVS develop, leading to cognitive dysfunction. In an SAH model using humanized UTh+/h+ male mice, we show that post-SAH CVS and behavioral deficits, mediated by UT through Gq/PLC/Ca2+ signaling, are prevented by UT antagonists. These results highlight the potential of targeting UT pathways to reduce early meningeal response and delayed cerebral ischemia in SAH patients.

Increased brain volume in the early phase of aneurysmal subarachnoid hemorrhage leads to delayed cerebral ischemia

Objective

To investigate the correlation between the swelling rate of brain volume within the first 48 h after aneurysmal subarachnoid hemorrhage and the subsequent development of delayed cerebral ischemia.

Methods

A retrospective analysis was conducted on patients with spontaneous aneurysmal subarachnoid hemorrhage admitted to the Neurosurgery Intensive Care Unit of the First Affiliated Hospital of Chongqing Medical University between January 2020 and January 2023. The clinical data, treatment outcomes, and imaging data were analyzed. Brain volume was evaluated using 3D-Slicer software at two time points post-hemorrhage: within the first 24 h and between 24 and 48 h. The swelling rate of brain volume was defined as the ratio of the absolute difference between two measurements to the smaller of values. Patients were categorized into two groups based on established diagnostic criteria of delayed cerebral ischemia. Univariate and multivariate logistic regression analyses were performed to identify factors influencing delayed cerebral ischemia.

Results

A total of 140 patients were enrolled in this study. 46 patients experienced delayed cerebral ischemia after bleeding. The swelling rate of brain volume was larger in the DCI group (10.66 ± 8.45) compared to the non-DCI group (3.59 ± 2.62), which showed a statistically significant difference. Additionally, advanced age, smoking history, history of hypertension, loss of consciousness, poor Hunt-Hess grade, high mFisher score, brain volume within 24 h, and IVH were also statistically different between the two groups. Multivariate logistic regression analysis revealed that the swelling rate of brain volume was an independent risk factor for DCI with adjusting the advanced age, smoking history, history of hypertension, poor Hunt-Hess grade, high mFisher score, brain volume within 24 h, and IVH.

Conclusion

Brain volume significantly increased in patients with aneurysmal subarachnoid hemorrhage during the early phase (within 48 h post-onset). The larger swelling rate of brain volume is an independent risk factor for the development of delayed cerebral ischemia, and it may hold significant predictive value for the incidence of delayed cerebral ischemia.

Ultrasound-Induced Release Profile of Nimodipine from Drug-Loaded Block Copolymers after Singular vs. Repeated Sonication: In Vitro Analysis in Artificial Cerebrospinal Fluid

OBJECTIVE

Nimodipine still represents a unique selling point in the prevention of delayed cerebral ischemia (DCI) following aneurysmal subarachnoid hemorrhage (aSAH). Its intrathecal effect is limited by a low oral bioavailability, leading to the development of nanocarrier systems to overcome this limitation. This study investigated the ultrasound-induced release profile of nimodipine from drug-loaded copolymers in artificial cerebrospinal fluid (CSF) within 72 h after a singular versus repeated sonication.

METHODS

Pluronic® F127 copolymers (Sigma-Aldrich, Taufkirchen, Germany)were loaded with nimodipine by direct dissolution. Spontaneous and on-demand drug release by ultrasound (1 MHz at 1.7 W/cm2) was determined in artificial cerebrospinal fluid using the dialysis bag method. Nimodipine concentrations were measured at predefined time points within 72 h of sonication.

RESULTS

Spontaneous release of nimodipine was enhanced by ultrasound application with significantly increased nimodipine concentrations two hours after a repeated sonication compared to a singular sonication (median 1.62 vs. 17.48 µg/µL, p = 0.04). A further trend was observed after four hours (median 1.82 vs. 22.09 µg/µL, p = 0.06). There was no difference in the overall nimodipine concentrations between the groups with a singular versus repeated sonication (357.2 vs. 540.3 µg/µL, p = 0.60) after 72 h.

CONCLUSIONS

Repeated sonication resulted in an acceleration of nimodipine release from the drug-loaded copolymer in a CSF medium. These findings confirm the proof of principle of an on-demand guidance of nimodipine release from nimodipine-loaded nanodrugs by means of ultrasound, which suggests that evaluating the concept in an animal model may be appropriate.

Clinical Characteristics as Predictors of Early and Delayed Cerebral Infarction in Aneurysmal Subarachnoid Hemorrhage Patients: A Meta-Analysis of 4527 Cases

BACKGROUND

Predictors of delayed cerebral infarction (DCI) and early cerebral infraction (ECI) among aneurysmal subarachnoid hemorrhage (aSAH) patients remain unclear. We aimed to systematically review and synthesize the literature on predictors of ECI and DCI among aSAH patients.

METHODS

We systematically searched PubMed, EMBASE, Cochrane Library, and Scopus databases comprehensively from inception through January 2024 for observational cohort studies examining predictors of DCI or ECI following aneurysmal SAH. Studies were screened, reviewed, and meta-analyzed, adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses and Cochrane guidelines. The data were pooled as Odds ratios (OR) with 95% confidence intervals using Review Manager 5.4 software. Methodologic quality was assessed with the Newcastle-Ottawa Scale.

RESULTS

Our meta-analysis included 12 moderate to high-quality cohort studies comprising 4527 patients. Regarding DCI predictors, Higher severity scores (OR = 1.49, 95% confidence interval [1.12, 1.97], P = 0.005) and high Fisher scores (OR = 2.23, 95% confidence interval [1.28, 3.89], P = 0.005) on presentation were significantly associated with an increased risk of DCI. Also, the female sex and the presence of vasospasm were significantly associated with an increased risk of DCI (OR = 3.04, 95% confidence interval [1.35, 6.88], P = 0.007). In contrast, preexisting hypertension (P = 0.94), aneurysm treatment (P = 0.14), and location (P = 0.16) did not reliably predict DCI risk. Regarding ECI, the pooled analysis demonstrated no significant associations between sex (P = 0.51), pre-existing hypertension (P = 0.63), severity (P = 0.51), or anterior aneurysm location versus posterior (P = 0.86) and the occurrence of ECI.

CONCLUSION

Female sex, admission disease severity, presence of vasospasm and Fisher grading can predict DCI risk post-aSAH. Significant knowledge gaps exist for ECI predictors. Further large standardized cohorts are warranted to guide prognosis and interventions.

Decreased timing to vasospasm prophylaxis improves outcomes among patients with aneurysmal subarachnoid hemorrhage (aSAH) on prehospital CCBs, ARBs, or ACE-inhibitors

INTRODUCTION

Aneurysmal subarachnoid hemorrhage (aSAH) patients are given calcium channel blockers (CCBs) to prevent brain vessel vasospasm. We hypothesized that preinjury antihypertensive use may protect against vasospasm. It remains unclear whether the timing of in-hospital CCB initiation affects the vasospasm risk in this population.

METHODS

This retrospective cohort study included aSAH patients (≥18 y/o) at a Comprehensive Stroke Center (1/18-11/21). Patients taking prehospital antihypertensives [CCBs, Angiotensin-converting enzyme (ACE) inhibitors or Angiotensin II receptor blockers (ARBs)] were compared to those who were not. Results were stratified by patients receiving vasospasm prophylaxis ('in-hospital CCBs') ≤1.2 h of arrival vs. >1.2 h from arrival. Outcomes included vasospasm, hospital length of stay (LOS), and mortality.

RESULTS

Of 251 patients, 18% were taking prehospital antihypertensives. Patients were comparable in baseline characteristics. There was no difference in the rate of vasospasm when compared by prehospital antihypertensive use. For those on prehospital antihypertensives, the time to in-hospital CCBs was significantly longer for patients who developed vasospasm than for those who did not (1.2 vs. 4.9 h, respectively, p = 0.02). For those on prehospital antihypertensives, receipt of in-hospital CCBs within 1.2 h of arrival was associated with a significantly lower vasospasm rate (6% vs. 39%, p = 0.03) and LOS (14 vs. 20 d, p = 0.01) when compared to receiving in-hospital CCBs > 1.2 h of arrival, respectively. The mortality rate (50% vs. 26%, p = 0.06) was statistically similar between groups, respectively. These results were not observed among patients who were not on prehospital antihypertensives. The timing to in-hospital CCB initiation had no effect on vasospasm (p = 0.23), death (p = 0.08), or LOS (p = 0.31) for patients not on prehospital antihypertensives.

CONCLUSIONS

Enhancing the efficiency of in-hospital CCB initiation for patients on prehospital antihypertensives may decrease the occurrence of vasospasm and lead to a shorter LOS.

Volatile Sedation in Neurointensive Care Patients After Aneurysmal Subarachnoid Hemorrhage: Effects on Delayed Cerebral Ischemia, Cerebral Vasospasm, and Functional Outcome

BACKGROUND

Volatile anesthetics have shown neuroprotective effects in preclinical studies, but clinical data on their use after aneurysmal subarachnoid hemorrhage (aSAH) are limited. This study aimed to analyze whether the use of volatile anesthetics for neurocritical care sedation affects the incidence of delayed cerebral ischemia (DCI), cerebral vasospasm (CVS), DCI-related infarction, or functional outcome.

METHODS

Data were retrospectively collected for ventilated aSAH patients (2016-2022), who received sedation for at least 180 hours. For comparative analysis, patients were assigned to a control and a study group according to the sedation used (intravenous vs. volatile sedation). Logistic regression analysis was performed to identify independent predictors of DCI, CVS, DCI-related infarction, and functional outcome.

RESULTS

Ninety-nine patients with a median age of 58 years (interquartile range: 52-65 years) were included. Forty-seven patients (47%) received intravenous sedation, while 52 patients (53%) received (additional) volatile sedation with isoflurane (n = 30, 58%) or sevoflurane (n = 22, 42%) for a median duration of 169 hours (range: 5-298 hours). There were no significant differences between the 2 groups regarding the occurrence of DCI, angiographic CVS, DCI-related infarction, or functional outcome. In a multivariable logistic regression analysis, the use of volatile anesthetics had no impact on the incidence of DCI-related infarction or the patients' functional outcome.

CONCLUSIONS

Volatile sedation in aSAH patients is not associated with the incidence of DCI, CVS, DCI-related infarction, or functional outcome. Although we could not demonstrate neuroprotective effects of volatile anesthetics, our results suggest that volatile sedation after aSAH has no negative effect on the patient's outcome.

Identification of key genes and immune infiltration in peripheral blood biomarker analysis of delayed cerebral ischemia: Valproic acid as a potential therapeutic drug

BACKGROUND

Delayed cerebral ischemia (DCI) is a common and serious complication of subarachnoid hemorrhage (SAH). Its pathogenesis is not fully understood. Here, we developed a predictive model based on peripheral blood biomarkers and validated the model using several bioinformatic multi-analysis methods.

METHODS

Six datasets were obtained from the GEO database. Characteristic genes were screened using weighted correlation network analysis (WGCNA) and differentially expressed genes. Three machine learning algorithms, elastic networks-LASSO, support vector machines (SVM-RFE) and random forests (RF), were also used to construct diagnostic prediction models for key genes. To further evaluate the performance and predictive value of the diagnostic models, nomogram model were constructed, and the clinical value of the models was assessed using Decision Curve Analysis (DCA), Area Under the Check Curve (AUC), Clinical Impact Curve (CIC), and validated in the mouse single-cell RNA-seq dataset. Mendelian randomization(MR) analysis explored the causal relationship between SAH and stroke, and the intermediate influencing factors. We validated this by retrospectively analyzing the qPCR levels of the most relevant genes in SAH and SAH-DCI patients. This experiment demonstrated a statistically significant difference between SAH and SAH-DCI and normal group controls. Finally, potential small molecule compounds interacting with the selected features were screened from the Comparative Toxicogenomics Database (CTD).

RESULTS

The fGSEA results showed that activation of Toll-like receptor signaling and leukocyte transendothelial cell migration pathways were positively correlated with the DCI phenotype, whereas cytokine signaling pathways and natural killer cell-mediated cytotoxicity were negatively correlated. Consensus feature selection of DEG genes using WGCNA and three machine learning algorithms resulted in the identification of six genes (SPOCK2, TRRAP, CIB1, BCL11B, PDZD8 and LAT), which were used to predict DCI diagnosis with high accuracy. Three external datasets and the mouse single-cell dataset showed high accuracy of the diagnostic model, in addition to high performance and predictive value of the diagnostic model in DCA and CIC. MR analysis looked at stroke after SAH independent of SAH, but associated with multiple intermediate factors including Hypertensive diseases, Total triglycerides levels in medium HDL and Platelet count. qPCR confirmed that significant differences in DCI signature genes were observed between the SAH and SAH-DCI groups. Finally, valproic acid became a potential therapeutic agent for DCI based on the results of target prediction and molecular docking of the characterized genes.

CONCLUSION

This diagnostic model can identify SAH patients at high risk for DCI and may provide potential mechanisms and therapeutic targets for DCI. Valproic acid may be an important future drug for the treatment of DCI.

Application of transcranial transmission ultrasound in the detection of vasospasm in patients with aneurysmal subarachnoid hemorrhage: illustrative cases

BACKGROUND

Effective management of patients with aneurysmal subarachnoid hemorrhage (aSAH) demands vigilant monitoring and treatment, given the risks of complications such as cerebral vasospasm and delayed ischemic neurological deficits (DINDs). Transcranial transmission ultrasound (TTUS) is a well-established technique for assessing brain pulsatility. This pilot study aims to explore the utility of TTUS in detecting impaired intracerebral blood flow associated with DINDs.

OBSERVATIONS

The authors examined 2 male patients, ages 45 and 52 years, with aSAH Hunt and Hess grades 4 and 2, respectively, who developed DINDs during their clinical course. Simultaneous recordings of arterial blood pressure, heart rate, and TTUS measurements were obtained in the intensive care unit. TTUS analysis revealed abnormal arrhythmic wave patterns during DIND episodes, whereas baseline measurements on DIND-free days showed no abnormalities. Following endovascular spasmolysis, TTUS demonstrated a normalization of abnormal waves, returning to baseline levels, alongside the resolution of neurological symptoms.

LESSONS

TTUS, a noninvasive method for assessing brain pulsatility, shows promise as a novel tool for monitoring aSAH patients, potentially aiding in prompt diagnostics and additional therapeutic interventions. Its capacity to provide further insights for individuals at risk of delayed cerebral ischemia warrants further investigation in clinical studies. https://thejns.org/doi/10.3171/CASE24146.

A Survey on Monitoring and Management of Cerebral Vasospasm and Delayed Cerebral Ischemia After Subarachnoid Hemorrhage: The Mantra Study

INTRODUCTION

Cerebral infarction from delayed cerebral ischemia (DCI) is a leading cause of poor neurological outcome after aneurysmal subarachnoid hemorrhage (aSAH). We performed an international clinical practice survey to identify monitoring and management strategies for cerebral vasospasm associated with DCI in aSAH patients requiring intensive care unit admission.

METHODS

The survey questionnaire was available on the European Society of Intensive Care Medicine (May 2021-June 2022) and Neurocritical Care Society (April - June 2022) websites following endorsement by these societies.

RESULTS

There were 292 respondents from 240 centers in 38 countries. In conscious aSAH patients or those able to tolerate an interruption of sedation, neurological examination was the most frequently used diagnostic modality to detect delayed neurological deficits related to DCI caused by cerebral vasospasm (278 respondents, 95.2%), while in unconscious patients transcranial Doppler/cerebral ultrasound was most frequently used modality (200, 68.5%). Computed tomography angiography was mostly used to confirm the presence of vasospasm as a cause of DCI. Nimodipine was administered for DCI prophylaxis by the majority of the respondents (257, 88%), mostly by an enteral route (206, 71.3%). If there was a significant reduction in arterial blood pressure after nimodipine administration, a vasopressor was added and nimodipine dosage unchanged (131, 45.6%) or reduced (122, 42.5%). Induced hypertension was used by 244 (85%) respondents as first-line management of DCI related to vasospasm; 168 (59.6%) respondents used an intra-arterial procedure as second-line therapy.

CONCLUSIONS

This survey demonstrated variability in monitoring and management strategies for DCI related to vasospasm after aSAH. These findings may be helpful in promoting educational programs and future research.

The Impact of Fluid Balance on Acute Kidney Injury in Nontraumatic Subarachnoid Hemorrhage

Background: Nontraumatic subarachnoid hemorrhage (SAH) can lead to poor neurologic outcomes, particularly when delayed cerebral ischemia (DCI) occurs. Maintenance of euvolemia following SAH is thought to reduce the risk of DCI. However, attempts at maintaining euvolemia often err on the side of hypervolemia. In this study, we assessed the relationship between fluid balance and acute kidney injury (AKI) in SAH patients, assessing hypervolemia versus euvolemia and their impact on AKI. Methods: In a quaternary care center, neuroscience intensive care unit we conducted a retrospective longitudinal analysis in adult patients who suffered a nontraumatic SAH. Results: Out of 139 patients, 15 (10.8%) patients developed an AKI while hospitalized, with 7 stage I, 3 stage II, and 5 stage III injuries. Acute kidney injury patients had higher peak sodium (150.1 mEq/L vs 142.7 mEq/L, 95% confidence interval [CI]: [2.7-12.1 mEq/L]), higher discharge chloride (109.1 mEq/L vs 104.9 mEq/L, 95% CI: [0.7-7.6 mEq/L]), and lower hemoglobin at discharge (9.3 g/dL vs 11.3 g/dL, 95% CI: [1.0-2.9 g/dL]). At 7 days, AKI patients had a fluid balance that was 1.82 L higher (P = .04), and 3.38 L higher at 14 days (P = .02), in comparison to day 3. Acute kidney injury was associated with significant mortality increases. This increase in mortality was found at 30 days from admission with a 9.52-fold increase, and at 60 days with a 6.25-fold increase. As a secondary outcome, vasospasm (19 patients, 13.7%) showed no association with AKI. Conclusions: Acute kidney injury following SAH is correlated with clinically significant hypervolemia, elevated sodium, elevated chloride, decreased urine output, and decreased hemoglobin at discharge-risk factors for all SAH patients. This study further elucidates the harm of hypervolemia and gives greater practical evidence to physicians attempting to balance the dangers of vasospasm and AKI.

Predictive value of cerebrovascular time constant for delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage

Time constant of the cerebral arterial bed (τ) is a transcranial Doppler (TCD) based metric that is expected to quantify the transit time of red blood cells from the insonation point to the arteriole-capillary boundary during a cardiac cycle. This study aims to assess the potential of τ as an early predictor of delayed cerebral ischemia (DCI). Consecutive patients (56 ± 15 years) treated for aneurysmal subarachnoid haemorrhage were included in the study. τ was assessed through a modelling approach that involved simultaneous recordings of arterial blood pressure and cerebral blood flow velocity (CBFV) from TCD's first recordings. 71 patients were included. 17 patients experienced DCI. τ was significantly shorter in patients who later developed DCI: 187 ± 64 ms vs. 249 ± 184 ms; p = 0.040 with moderate effect size (rG = 0.24). Logistic regression showed that there was a significant association between increased CBFV, shortened τ, and the development of DCI (χ2 = 11.54; p = 0.003) with AUC for the model 0.75. Patients who had both shortened τ and increased CBFV were 20 times more likely to develop DCI (OR = 20.4 (2.2-187.7)). Our results suggest that early alterations in τ are associated with DCI after aSAH. The highest performance of the model including both CBFV and τ may suggest the importance of both macrovascular and microvascular changes assessment.

CT perfusion-guided administration of IV milrinone is associated with a reduction in delayed cerebral infarction after subarachnoid hemorrhage

Delayed cerebral ischemia (DCI) after aneurysmal subarachnoid haemorrhage (aSAH) is a singular pathological entity necessitating early diagnostic approaches and both prophylactic and curative interventions. This retrospective before-after study investigates the effects of a management strategy integrating perfusion computed tomography (CTP), vigilant clinical monitoring and standardized systemic administration of milrinone on the occurrence of delayed cerebral infarction (DCIn). The "before" period included 277 patients, and the "after" one 453. There was a higher prevalence of Modified Fisher score III/IV and more frequent diagnosis of vasospasm in the "after" period. Conversely, the occurrence of DCIn was reduced with the "after" management strategy (adjusted OR 0.48, 95% CI [0.26; 0.84]). Notably, delayed ischemic neurologic deficits were less prevalent at the time of vasospasm diagnosis (24 vs 11%, p = 0.001 ), suggesting that CTP facilitated early detection. In patients diagnosed with vasospasm, intravenous milrinone was more frequently administered (80 vs 54%, p < 0.001 ) and associated with superior hemodynamics. The present study from a large cohort of aSAH patients suggests, for one part, the interest of CTP in early diagnosis of vasospasm and DCI, and for the other the efficacy of CT perfusion-guided systemic administration of milrinone in both preventing and treating DCIn.

Nimodipine-associated standard dose reductions and neurologic outcomes after aneurysmal subarachnoid hemorrhage: the era of pharmacogenomics

Nimodipine, an L-type cerebroselective calcium channel antagonist, is the only drug approved by the US Food and Drug Administration for the neuroprotection of patients with aneurysmal subarachnoid hemorrhage (aSAH). Four randomized, placebo-controlled trials of nimodipine demonstrated clinical improvement over placebo; however, these occurred before precision medicine with pharmacogenomics was readily available. The standard enteral dose of nimodipine recommended after aSAH is 60 mg every 4 h. However, up to 78% of patients with aSAH develop systemic arterial hypotension after taking the drug at the recommended dose, which could theoretically limit its neuroprotective role and worsen cerebral perfusion pressure and cerebral blood flow, particularly when concomitant vasospasm is present. We investigated the association between nimodipine dose changes and clinical outcomes in a consecutive series of 150 patients (mean age, 56 years; 70.7% women) with acute aSAH. We describe the pharmacogenomic relationship of nimodipine dose reduction with clinical outcomes. These results have major implications for future individualized dosing of nimodipine in the era of precision medicine.

Low serum albumin as a risk factor for delayed cerebral ischemia following aneurysmal subarachnoid hemorrhage: eICU collaborative research database analysis

BACKGROUND

Delayed cerebral ischemia (DCI) represents a devastating complication of aneurysmal subarachnoid hemorrhage (aSAH) and is a significant predictor of morbidity and mortality. Recent studies have implicated inflammatory processes in the pathogenesis of DCI.

METHODS

aSAH patient data were retrospectively obtained from the eICU Collaborative Research Database (eICU CRD). Multivariable logistic regression models and receiver operating characteristic (ROC) curve analyses were employed to assess the association between low serum albumin (<3.4 g/dL) and clinical endpoints: DCI and in-hospital mortality.

RESULTS

Among 276 aSAH patients included in the analysis, 35.5% (N.=98) presented with low serum albumin levels and demonstrated a higher incidence of DCI (18.4% vs. 8.4%, OR=2.45, 95% CI=1.17, 5.10; P=0.017) and in-hospital mortality (27.6% vs. 16.3%, OR=1.95, 95% CI=1.08, 3.54; P=0.027) compared to patients with normal admission albumin values. In a multivariable model controlling for age and World Federation of Neurosurgical Societies grade, low serum albumin remained significantly associated with DCI (OR=2.52, 95% CI=1.18, 5.36; P=0.017), but not with in-hospital mortality. A combined model for prediction of DCI, encompassing known risk factors in addition to low serum albumin, achieved an area under the curve of 0.65 (sensitivity = 0.55, specificity = 0.75).

CONCLUSIONS

Serum albumin, a routine and inexpensive laboratory measurement, may potentially aid in the identification of patients with aSAH at risk for the development of DCI.

Early Intravenous Magnesium Sulfate and Its Impact on Cerebral Vasospasm as well as Delayed Cerebral Ischemia in Aneurysmal Subarachnoid Hemorrhage: A Retrospective Matched Case-Control Analysis

BACKGROUND

Magnesium sulfate (MgSO4) is a potential neuroprotective agent for patients with aneurysmal subarachnoid hemorrhage (SAH). We analyzed the effect of early application of intraoperative intravenous MgSO4 and compared cerebral vasospasm (CV), delayed cerebral ischemia (DCI), and neurological outcome in 2 patient cohorts.

METHODS

A retrospective matched-pair analysis from patients at a single center in Germany was performed without (group A) and with (group B) MgSO4 application <24 hours after diagnosis. Pairs were matched according to the known risk factors for DCI and CV (age, Fisher grade, smoking, severity of SAH). Incidence of CV and DCI and neurological outcome using the modified Rankin Scale score 3 and 12 months after SAH were recorded.

RESULTS

The inclusion criteria were met by 196 patients. After risk stratification, 48 patients were included in the final analysis (age 54.2 ± 8.1 years; 30 women and 18 men) and were assigned to group A (n = 24) or group B (n = 24). CV occurred less frequently in group B (33%) than in group A (46%). Likewise, DCI was present in 13% in group B compared with 42% in group A. After 12 months, 22 patients in group B had a favorable functional outcome (modified Rankin Scale score 0-3) compared with 15 patients in group A.

CONCLUSIONS

In this study, the incidence of CV and DCI was lower in patients receiving intravenous MgSO4 within 24 hours after aneurysmal SAH onset. Favorable functional outcome was more likely in the MgSO4 group after 12 months of follow-up.

Machine Learning Algorithms to Predict Delayed Cerebral Ischemia After Subarachnoid Hemorrhage: A Systematic Review and Meta-analysis

Delayed cerebral ischemia (DCI) is a common and severe complication after subarachnoid hemorrhage (SAH). Logistic regression (LR) is the primary method to predict DCI, but it has low accuracy. This study assessed whether other machine learning (ML) models can predict DCI after SAH more accurately than conventional LR. PubMed, Embase, and Web of Science were systematically searched for studies directly comparing LR and other ML algorithms to forecast DCI in patients with SAH. Our main outcome was the accuracy measurement, represented by sensitivity, specificity, and area under the receiver operating characteristic. In the six studies included, comprising 1828 patients, about 28% (519) developed DCI. For LR models, the pooled sensitivity was 0.71 (95% confidence interval [CI] 0.57-0.84; p < 0.01) and the pooled specificity was 0.63 (95% CI 0.42-0.85; p < 0.01). For ML models, the pooled sensitivity was 0.74 (95% CI 0.61-0.86; p < 0.01) and the pooled specificity was 0.78 (95% CI 0.71-0.86; p = 0.02). Our results suggest that ML algorithms performed better than conventional LR at predicting DCI.Trial Registration: PROSPERO (International Prospective Register of Systematic Reviews) CRD42023441586; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=441586.

Perfusion Computed Tomography as a Screening Tool for Pending Delayed Cerebral Ischemia in Comatose Patients After Aneurysmal Subarachnoid Hemorrhage: A Retrospective Cohort Study

BACKGROUND

Aneurysmal subarachnoid hemorrhage (aSAH) is frequently complicated by delayed cerebral ischemia (DCI), leading to poor outcomes. Early diagnosis of DCI is crucial for improving survival and outcomes but remains challenging in comatose patients. In this study, we aimed to evaluate computed tomography with angiography and perfusion (P-CT) as a screening modality on postictal days four and eight for impending DCI after aSAH in comatose patients using vasospasm with hypoperfusion (hVS) as a surrogate and DCI-related infarction as an outcome measure. Two objectives were set: (1) to evaluate the screening's ability to accurately risk stratify patients and (2) to assess the validity of P-CT screening.

METHODS

We conducted a retrospective review of the records of comatose patients with aSAH from January 2019 to December 2021 who were monitored with P-CT scans on days four and eight. The event rates of DCI-related infarction, hVS, and endovascular rescue therapy (ERT) were analyzed, and the sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) for DCI were calculated. DCI-related infarction was defined as new secondary cerebral infarction > 48 h < 6 weeks post aSAH not attributable to other causes, and hVS was defined as arterial narrowing with corresponding hypoperfusion on P-CT.

RESULTS

Fifty-six comatose patients were included, and 98 P-CT scans were performed. The incidence of DCI-related infarction was 40%. Screening P-CT on days four and eight found vasospasm in 23% of all patients, including 11% with hVS. A positive hVS on day four or eight revealed a relative risk of 2.4 [95% confidence interval (CI) 1.13-5.11, p = 0.03], sensitivity of 23% (95% CI 8-45, p = 0.03), specificity of 95% (95% CI 36-100, p = 0.03), PPV of 0.83 (95% CI 0.36-1.00, p = 0.03), and NPV of 0.65 (95% CI 0.50-0.78). Six positive P-CT scans led to digital subtraction angiography in five patients, three of whom received ERT. All ERT-intervened patients developed DCI-related infarction.

CONCLUSIONS

P-CT resulted in few interventions and often resulted in late detection of DCI at an irreversible stage. Although a positive P-CT result accurately predicts impending DCI-related infarction, screening on days four and eight alone in comatose patients with aSAH often fails to timely detect impending DCI. Based on our analysis, we cannot recommend P-CT as a screening modality. P-CT is likely best used as a confirmatory test prior to invasive interventions when guided by continuous multimodal monitoring; however, prospective studies with comparison groups are warranted. The need for a reliable continuous screening modality is evident because of the high rate of deterioration and narrow treatment window.

Intimal Hemorrhage of Basilar Artery Induced by Severe Vasospasm Following Subarachnoid Hemorrhage: The Experimental Analysis

BACKGROUND

 Cerebral vasospasm, a serious complication of subarachnoid hemorrhage (SAH), has been extensively studied for its neurochemical and pathophysiologic mechanisms. However, the contribution of inner elastic membrane dissection and subintimal hemorrhage to basilar artery occlusion remains underexplored. This study investigates inner elastic membrane-related changes in the basilar artery after SAH.

METHODS

 Twenty-four hybrid rabbits were divided into control, sham, and SAH groups, with SAH induced by autologous blood injection. After 2 weeks, basilar artery changes, vasospasm indexes (VSIs), and dissections were evaluated.

RESULTS

 The SAH group showed significantly higher VSI, with vascular wall thickening, luminal narrowing, convoluted smooth muscle cells, intimal elastic membrane disruption, endothelial cell desquamation, and apoptosis. Some SAH animals exhibited subintimal hemorrhage, inner elastic membrane dissection, and ruptures. Basilar arteries with subintimal hemorrhage had notably higher VSI.

CONCLUSIONS

 These findings highlight the role of subintimal hemorrhage and inner elastic membrane dissection in basilar artery occlusion post-SAH, offering valuable insights into vasospasm pathophysiology.

Therapeutic Potential of Natural Compounds in Subarachnoid Haemorrhage

Subarachnoid hemorrhage (SAH) is a common and fatal cerebrovascular disease with high morbidity, mortality and very poor prognosis worldwide. SAH can induce a complex series of pathophysiological processes, and the main factors affecting its prognosis are early brain injury (EBI) and delayed cerebral ischemia (DCI). The pathophysiological features of EBI mainly include intense neuroinflammation, oxidative stress, neuronal cell death, mitochondrial dysfunction and brain edema, while DCI is characterized by delayed onset ischemic neurological deficits and cerebral vasospasm (CVS). Despite much exploration in people to improve the prognostic outcome of SAH, effective treatment strategies are still lacking. In recent years, numerous studies have shown that natural compounds of plant origin have unique neuro- and vascular protective effects in EBI and DCI after SAH and long-term neurological deficits, which mainly include inhibition of inflammatory response, reduction of oxidative stress, anti-apoptosis, and improvement of blood-brain barrier and cerebral vasospasm. The aim of this paper is to systematically explore the processes of neuroinflammation, oxidative stress, and apoptosis in SAH, and to summarize natural compounds as potential targets for improving the prognosis of SAH and their related mechanisms of action for future therapies.

Triglyceride Glucose Index and Prognosis of Patients with Subarachnoid Hemorrhage

OBJECTIVE

The triglyceride glucose (TyG) index is regarded as a reliable alternative indicator for measuring insulin resistance. We investigated the association between the prognosis of patients with subarachnoid hemorrhage (SAH)and the TyG index, explored the potential of the TyG index as a new biomarker for forecasting the outcomes of SAH patients, and explored independent risk factors for predicting the condition of SAH patients.

METHODS

A retrospective analysis was performed of patients who were admitted to a single center due to SAH. Differences in clinical data and correlation between laboratory indexes, disease severity score on admission, and prognosis score were compared between the 2 groups. The study employed multivariate logistic regression analysis to examine the independent influencing aspects of Glasgow Outcome Scale score. The receiver operating characteristic curve was drawn and the area under the curve (AUC) calculated to predict the best cutoff value of the degree of neurological impairment in patients with SAH.

RESULTS

Univariate analysis showed that Glasgow Coma Scale score (86.3% vs. 12.0%, P < 0.001), Hunt-Hess grade (88.2% vs. 15.7%, P < 0.001), white blood cell count (11.20 [7.9, 15.2] vs. 9.1 [7.0, 12.2], P = 0.027), and TyG index (1.49 [1.40, 1.59] vs. 1.16 [1.06, 1.27], P < 0.001) were statistically significantly different. Multivariate analysis showed that TyG index, Hunt-Hess grade, and GCS score were independent risk factors for poor prognosis.

CONCLUSIONS

Patients with SAH may benefit from using the TyG index as a predictive method. In our clinical practice, the TyG index is beneficial for managing diseases and making decisions. More research is required to determine if improved TyG index control would lead to better clinical results in the future.

MR Imaging Techniques for Acute Ischemic Stroke and Delayed Cerebral Ischemia Following Subarachnoid Hemorrhage

Acute ischemic stroke (AIS) is a leading cause of death and disability worldwide, and its prevalence is expected to increase with global population aging and the burgeoning obesity epidemic. Clinical care for AIS has evolved during the past 3 decades, and it comprises of 3 major tenants: (1) timely recanalization of occluded vessels with intravenous thrombolysis or endovascular thrombectomy, (2) prompt initiation of antithrombotic agents to prevent stroke recurrences, and (3) poststroke supportive care and rehabilitation. In this article, we summarize commonly used MR sequences for AIS and DCI and highlight their clinical applications.

Anemia and Optimal Transfusion Thresholds in Brain-Injured Patients: A Narrative Review of the Literature

Anemia is a highly prevalent condition that may compromise oxygen delivery to vital organs, especially among the critically ill. Although current evidence supports the adoption of a restrictive transfusion strategy and threshold among the nonbleeding critically ill patient, it remains unclear whether this practice should apply to the brain-injured patient, given the predisposition to cerebral ischemia in this patient population, in which even nonprofound anemia may exert a detrimental effect on clinical outcomes. The purpose of this review is to provide an overview of the pathophysiological changes related to impaired cerebral oxygenation in the brain-injured patient and to present the available evidence on the effect of anemia and varying transfusion thresholds on the clinical outcomes of patients with acute brain injury.

Elevated cortical blood flow insufficiency volume as a predictor of adverse outcomes in aneurysmal subarachnoid hemorrhage: a large prospective quantitative computed tomography perfusion study

PURPOSE

Early hypoperfusion changes exist in patients with aneurysmal subarachnoid hemorrhage (aSAH). We aimed to investigate a readily obtainable quantitative computed tomography perfusion (CTP) parameter that could assist in quickly identifying patients at risk of delayed cerebral ischemia (DCI) and poor 90-day functional outcomes on admission.

METHODS

We prospectively collected data between 2021.04 and 2022.12. Preoperative CTP data were post-processed using RAPID software. The cortical blood flow insufficiency (CBFI) was defined as Time-to-maximum > 4.0 s. Patients were categorized into four groups according to CBFI volume distribution. To minimize differences among the groups, we employed stabilized inverse probability of treatment weighting (sIPTW). The primary outcome was DCI and poor 90-day functional outcomes (modified Rankin Scale, 3-6) was the secondary outcome. Multivariable Cox or Logistic analysis were performed to estimate the association between CBFI volume and the study outcomes, both before and after sIPTW.

RESULTS

At baseline, the mean (SD) age of the 493 participants was 55.0 (11.8) years, and 299 (60.6%) were female. One hundred and seven participants with DCI and eighty-six participants with poor 90-day functional outcomes were identified. After sIPTW, CBFI volume demonstrated a significant association with DCI (Cox regression: Group 4 versus Group 1, HR 3.69, 95% CI 1.84-7.01) and poor 90-day functional outcomes (Logistic regression: Group 4 versus Group 1, OR 4.61, 95% CI 2.01-12.50).

CONCLUSION

In this study, an elevated preoperative CBFI volume was associated with adverse outcomes in aSAH patients. More well-designed studies are needed to confirm this association.

Nanothermometry for cellular temperature monitoring and disease diagnostics

Body temperature variations, including the generation, transfer, and dissipation of heat, play an important role throughout life and participate in all biological events. Cellular temperature information is an indispensable link in the comprehensive understanding of life science processes, but traditional testing strategies cannot provide sufficient information due to their low precision and inefficient cellular‐entrance. In recent years, with the help of luminescent nanomaterials, a variety of new thermometers have been developed to achieve real‐time temperature measurement at the micro/nano scale. In this review, we summarized the latest advances in several nanoparticles for cellular temperature detection and their related applications in revealing cell metabolism and disease diagnosis. Furthermore, this review proposed a few challenges for the nano‐thermometry, expecting to spark novel thought to push forward its preclinical and translational uses.

First use of intraventricular nicardipine in a pediatric patient with vasospasm secondary to meningitis: illustrative case

BACKGROUND

Cerebral vasospasm is commonly associated with adult aneurysmal subarachnoid hemorrhage but can develop in children. The standard vasospasm treatment includes induced hypertension, avoidance of hypovolemia, systemic use of the calcium channel blocker (CCB) nimodipine, and cerebral angiography for intraarterial therapy. Emerging treatments in adults, such as intraventricular CCB administration, have not been investigated in children. This study demonstrates the successful use of an intraventricular CCB in a pediatric patient with refractory vasospasm secondary to meningitis.

OBSERVATIONS

A 12-year-old female presented with Streptococcus pneumoniae meningitis and ventriculitis with refractory symptomatic cerebral vasospasm. She received a 5-day course of intrathecal nicardipine through an existing external ventricular drain. Her clinical status, transcranial Doppler studies, and radiography improved. Treatment was well tolerated.

LESSONS

Pediatric vasospasm is uncommon and potentially devastating. The management of vasospasm in adults occurs frequently. Principles of this management are adapted to pediatric care given the rarity of vasospasm in children. The use of intraventricular nicardipine has been reported in the care of adults with level 3 evidence. It has not been adequately reported in children with refractory vasospasm. Here, the first use of intraventricular nicardipine in treating pediatric cerebral vasospasm in the setting of meningitis is described and highlighted.

Advances in biomarkers for vasospasm - Towards a future blood-based diagnostic test

Objective

Cerebral vasospasm and the resultant delayed cerebral infarction is a significant source of mortality following aneurysmal SAH. Vasospasm is currently detected using invasive or expensive imaging at regular intervals in patients following SAH, thus posing a risk of complications following the procedure and financial burden on these patients. Currently, there is no blood-based test to detect vasospasm.

Methods

PubMed, Web of Science, and Embase databases were systematically searched to retrieve studies related to cerebral vasospasm, aneurysm rupture, and biomarkers. The study search dated from 1997 to 2022. Data from eligible studies was extracted and then summarized.

Results

Out of the 632 citations screened, only 217 abstracts were selected for further review. Out of those, only 59 full text articles met eligibility and another 13 were excluded.

Conclusions

We summarize the current literature on the mechanism of cerebral vasospasm and delayed cerebral ischemia, specifically studies relating to inflammation, and provide a rationale and commentary on a hypothetical future bloodbased test to detect vasospasm. Efforts should be focused on clinical-translational approaches to create such a test to improve treatment timing and prediction of vasospasm to reduce the incidence of delayed cerebral infarction.

Stellate Ganglion Block and Intraarterial Spasmolysis in Patients with Cerebral Vasospasm: A Retrospective Cohort Study

BACKGROUND

In patients with symptomatic cerebral vasospasm (CV) following aneurysmal subarachnoid hemorrhage who do not respond to medical therapy, urgent treatment escalation has been suggested to be beneficial for brain tissue at risk. In our routine clinical care setting, we implemented stellate ganglion block (SGB) as a rescue therapy with subsequent escalation to intraarterial spasmolysis (IAS) with milrinone for refractory CV.

METHODS

In this retrospective analysis from 2012 to 2021, patients with CV following aneurysmal subarachnoid hemorrhage who received an SGB or IAS were identified. Patients were assessed through neurological examination and transcranial Doppler. Rescue therapy was performed in patients with mean cerebral blood flow velocity (CBFV) ≥ 120 cm/s and persistent neurological deterioration/intubation under induced hypertension. Patients were reassessed after therapy and the following day. The Glasgow Outcome Scale was assessed at discharge and 6-month follow-up.

RESULTS

A total of 82 patients (mean age 50.16 years) with 184 areas treated with SGB and/or IAS met the inclusion criteria; 109 nonaffected areas were extracted as controls. The mean CBFV decrease in the middle cerebral artery on the following day was - 30.1 (± 45.2) cm/s with SGB and - 31.5 (± 45.2) cm/s with IAS. Mixed linear regression proved the significance of the treatment categories; other fixed effects (sex, age, aneurysm treatment modality [clipping or coiling], World Federation of Neurological Surgeons score, and Fisher score) were insignificant. In logistic regression, the presence of cerebral infarction on imaging before discharge from the intensive care unit (34/82) was significantly associated with unfavorable outcomes (Glasgow Outcome Scale ≤ 3) at follow-up.

CONCLUSIONS

Stellate ganglion block and IAS decreased CBFV the following 24 h in patients with CV. We suggest SGB alone for patients with mild symptomatic CV (CBFV < 180 cm/s), while subsequent escalation to IAS proved to be beneficial in patients with refractory CV and severe CBFV elevation (CBFV ≥ 180 cm/s).

Immediate angiographic control after intra-arterial nimodipine administration underestimates the vasodilatory effect

Intra-arterial nimodipine administration is a widely used rescue therapy for cerebral vasospasm. Although it is known that its effect sets in with delay, there is little evidence in current literature. Our aim was to prove that the maximal vasodilatory effect is underestimated in direct angiographic controls. We reviewed all cases of intra-arterial nimodipine treatment for subarachnoid hemorrhage-related cerebral vasospasm between January 2021 and December 2022. Inclusion criteria were availability of digital subtraction angiography runs before and after nimodipine administration and a delayed run for the most affected vessel at the end of the procedure to decide on further escalation of therapy. We evaluated nimodipine dose, timing of administration and vessel diameters. Delayed runs were performed in 32 cases (19 patients) with a mean delay of 37.6 (± 16.6) min after nimodipine administration and a mean total nimodipine dose of 4.7 (± 1.2) mg. Vessel dilation was more pronounced in delayed vs. immediate controls, with greater changes in spastic vessel segments (n = 31: 113.5 (± 78.5%) vs. 32.2% (± 27.9%), p < 0.0001) vs. non-spastic vessel segments (n = 32: 23.1% (± 13.5%) vs. 13.3% (± 10.7%), p < 0.0001). In conclusion intra-arterially administered nimodipine seems to exert a delayed vasodilatory effect, which should be considered before escalation of therapy.

Comparison of efficacy between clazosentan and fasudil hydrochloride-based management of vasospasm after subarachnoid hemorrhage focusing on older and WFNS grade V patients: a single-center experience in Japan

Subarachnoid hemorrhage often leads to poor outcomes owing to vasospasm, even after successful aneurysm treatment. Clazosentan, an endothelin receptor inhibitor, has been proven to be an effective treatment for vasospasms in a Japanese randomized controlled trial. However, its efficacy in older patients (≥ 75 years old) and those with World Federation of Neurosurgical Societies (WFNS) grade V has not been demonstrated. We retrospectively evaluated the efficacy of clazosentan in older patients and those with WFNS grade V, using real-world data. Patients with subarachnoid hemorrhage treated before and after the introduction of clazosentan were retrospectively evaluated. The patients were categorized into two groups (clazosentan era versus pre-clazosentan era), in which vasospasm management and outcomes were compared. Vasospasms were managed with fasudil hydrochloride-based (pre-clazosentan era) or clazosentan-based treatment (clazosentan era). Seventy-eight patients were included in this study: the clazosentan era (n = 32) and pre-clazosentan era (n = 46). Overall, clazosentan significantly reduced clinical vasospasms (clazosentan era: 31.3% versus pre-clazosentan era: 60.9%, p = 0.01), delayed cerebral ischemia (DCI) (9.4% versus 39.1%, p = 0.004), and vasospasm-related morbidity and mortality (M/M) (3.1% versus 19.6%, p = 0.03). In subgroup analysis of older patients or those with WFNS grade V, no significant difference was observed in clinical outcomes, although both DCI and vasospasm-related M/M were lower in the clazosentan era. Clazosentan was more effective than fasudil-based management in preventing DCI and reducing vasospasm-related M/M. Clazosentan could be used safely in older patients and those with WFNS grade V, although clinical outcomes in these patients were comparable to those of conventional treatment.

Alpha-lipoic acid (ALA) ameliorates early brain injury after subarachnoid hemorrhage in Sprague-Dawley (SD) rats via inhibiting STING-NLRP3 inflammatory signaling

Neuroinflammation is intimately associated with poor prognosis in patients with subarachnoid hemorrhage (SAH). Alpha-lipoic acid (ALA), a disulfide antioxidant, has been shown to be neuroprotective in an in vivo model of neurological injury; however, the role of ALA in SAH has never been evaluated. In this study, the Sprague-Dawley rats SAH model was induced by endovascular perforation method. ALA was transplanted intravenously into rats, and SR-717, a stimulator of interferon genes (STING) agonist, was injected intraperitoneally. The effects of ALA on early brain injury were assayed by neurological score, hematoxylin and eosin staining and Nissl staining. Immunohistochemistry staining and Western blotting were used to analyze various proteins. ALA significantly reduced STING- NLRP3 protein expression and decreased cell death, which in turn mitigated the neurobehavioral dysfunction following SAH. Furthermore, coadministration of ALA and SR-717 promoted STING-NLRP3 signaling pathway activation following SAH, which reversed the inhibitory effect of ALA on STING-NLRP3 protein activation and increased the neurological deficits. In conclusion, ALA may be a promising therapeutic strategy for alleviating early brain injury after SAH.

The impact of perfusion computed tomography on the diagnosis and outcome of delayed cerebral ischemia after subarachnoid hemorrhage

BACKGROUND

Delayed cerebral ischemia (DCI) is a preventable cause of poor neurological outcome in aneurysmal subarachnoid hemorrhage (aSAH). Advances in radiological methods, such as cerebral perfusion computed tomography (CTP), could help diagnose DCI earlier and potentially improve outcomes in aSAH. The objective of this study was to assess whether the use of CTP to diagnose DCI early could reduce the risk of infarction related to DCI.

METHODS

Retrospective cohort study of patients in the intensive care unit of Erasme Hospital (Brussels, Belgium) between 2004 and 2021 with aSAH who developed DCI. Patients were classified as: "group 1" - DCI diagnosed based on clinical deterioration or "group 2" - DCI diagnosed using CTP. The primary outcome was the development of infarction unrelated to the initial bleeding or surgery.

RESULTS

211 aSAH patients were diagnosed with DCI during the study period: 139 (66%) in group 1 and 72 (34%) in group 2. In group 1, 109 (78%) patients developed a cerebral infarction, compared to 45 (63%) in group 2 (p = 0.02). The adjusted cumulative incidence of DCI over time was lower in group 2 than in group 1 [hazard ratio 0.65 (95% CI 0.48-0.94); p = 0.02]. The use of CTP to diagnose DCI was not independently associated with mortality or neurological outcome.

CONCLUSIONS

The use of CTP to diagnose DCI might help reduce the risk of developing cerebral infarction after aSAH, although the impact of such an approach on patient outcomes needs to be further demonstrated.

Emerging Treatments for Subarachnoid Hemorrhage

The current landscape of therapeutic strategies for subarachnoid hemorrhage (SAH), a significant adverse neurological event commonly resulting from the rupture of intracranial aneurysms, is rapidly evolving. Through an in-depth exploration of the natural history of SAH, historical treatment approaches, and emerging management modalities, the present work aims to provide a broad overview of the shifting paradigms in SAH care. By synthesizing the historical management protocols with contemporary therapeutic advancements, patient-specific treatment plans can be individualized and optimized to deliver outstanding care for the best possible SAH-related outcomes.

"No-reflow" phenomenon in acute ischemic stroke

Acute ischemic stroke (AIS) afflicts millions of individuals worldwide. Despite the advancements in thrombolysis and thrombectomy facilitating proximal large artery recanalization, the resultant distal hypoperfusion, referred to "no-reflow" phenomenon, often impedes the neurological function restoration in patients. Over half a century of scientific inquiry has validated the existence of cerebral "no-reflow" in both animal models and human subjects. Furthermore, the correlation between "no-reflow" and adverse clinical outcomes underscores the necessity to address this phenomenon as a pivotal strategy for enhancing AIS prognoses. The underlying mechanisms of "no-reflow" are multifaceted, encompassing the formation of microemboli, microvascular compression and contraction. Moreover, a myriad of complex mechanisms warrant further investigation. Insights gleaned from mechanistic exploration have prompted advancements in "no-reflow" treatment, including microthrombosis therapy, which has demonstrated clinical efficacy in improving patient prognoses. The stagnation in current "no-reflow" diagnostic methods imposes limitations on the timely application of combined therapy on "no-reflow" post-recanalization. This narrative review will traverse the historical journey of the "no-reflow" phenomenon, delve into its underpinnings in AIS, and elucidate potential therapeutic and diagnostic strategies. Our aim is to equip readers with a swift comprehension of the "no-reflow" phenomenon and highlight critical points for future research endeavors.

Management of neurological complications related to aneurysmal subarachnoid hemorrhage: A comparison of the bedside therapeutic algorithms

BACKGROUND

Aneurysmal subarachnoid hemorrhage (aSAH) is of the most serious emergencies in neurosurgical practice and continues to be associated with high morbidity and mortality. Beyond securing the ruptured aneurysm to prevent a rebleed, physicians continue to be concerned about potential complications such as cerebral vasospasm-delayed cerebral ischemia (DCI), an area where management remains highly variable. This study aimed at reviewing the most recent literature and assessing any up-to-date schemes for treating the most common aSAH neurological complications in adults that can be applied in daily clinical practice towards optimising outcomes.

METHODS

A systematic review was performed according to PRISMA guidelines on the management of aSAH neurological complications in adults. The literature surveyed was between 2016 and 2022 inclusive, using the Pubmed search engine. Comparisons between the methods suggested by existing therapeutic algorithms were discussed.

RESULTS

Six stepwise algorithms assisting the decision-making for treating cerebral vasospasm-DCI were recognised and compared. No algorithm was found for the management of any other neurological complications of aSAH. Despite differences in the algorithms, induced hypertension and endovascular therapy were common treatments in all approaches. Controversy in the therapeutic process of these complications surrounds not only the variability of methods but also their optimal application towards clinical outcome optimisation.

CONCLUSIONS

A universal approach to managing aSAH complications is lacking. Despite advances in the techniques to secure a ruptured aneurysm, there persist a high rate of neurological deficit and mortality, and several unanswered questions. More research is required towards stratification of current treatment algorithms as per the quality of their evidence.