Nimodipine for the prevention of cerebral vasospasm after subarachnoid hemorrhage in 12 children

Cerebral Vasospasm as a Critical Yet Overlooked Complication Following Tumor Craniotomy: A Systematic Review of Case Reports and Case Series

Background: Cerebral vasospasm after craniotomy tumor (CVACT) is a rare complication that can occur following tumor craniotomy and significantly affects the outcome of patients. Unfortunately, it is not well understood, leading to delayed and ineffective management. This study aims to investigate CVACT by examining the factors contributing to its occurrence, its underlying mechanisms, diagnostic approaches, management strategies, and outcomes. The goal is to identify the characteristics and risk factors associated with CVACT, its clinical symptoms, diagnostic methods, management options, and potential outcomes. Methods: A systematic search used relevant keywords to identify cases of "cerebral vasospasm" after tumor resection in PubMed and Science Direct databases. Relevant cross-references were added by manually searching the references of all retrieved articles. Result: We included 60 inclusion patients from 14 case reports and 13 case series with 33 (55%) females and 27 (45%) males with a mean age of 44.05 ± 16.8 years. The most common tumors were pituitary adenomas, which were found in 22 (36.66%), the most common tumor location was the middle cranial fossa (75%), and the most common surgery technique used was transsphenoidal surgery (50%). Most of those who experience vasospasm have a craniotomy with the TSS technique (50%) with complications of intraoperative bleeding. The range of onset of VS symptoms postoperatively was 0-30 days (mean 6.59 d). The symptoms included asymptomatic, headache, loss of vision, hemiparesis, diplopia, etc. The vascular involvement was mainly anterior circulation (78.33%). The diagnostic tools most commonly used were angiography and transcranial doppler (TCD). The most common management of VS from the included studies was pharmacology. The survival rate was 61.66%. We found the tumor location and vascular-affected vasospasm were significantly correlated with mortality rates: p = 0.015 and p = 0.02. Conclusions: Cerebral vasospasm after craniotomy tumor removal (CVACT) frequently arises in tumors situated in the medial cranial fossa, predominantly pituitary adenomas and meningiomas. The minimally invasive surgical approach of TSS may contribute to the mechanism of CVACT incidence. The existence of preoperative vascular pathology, as encasement or narrowing, appears to be a predictor alongside the incidence of intra- or postoperative hemorrhage. The vascular structures most susceptible to vasospasm are located in the anterior circulation of the Willis circle, which appears to correlate with the vascular problems that typically undergo preoperative encasement of the internal carotid artery (ICA). The most reliable and real time diagnostic instrument employed is TCD, while imaging continues to be the gold standard. Nimodipine treatment continues to be a viable therapeutic option that can enhance patient outcomes.

Balloon angioplasty for cerebral vasospasm in preschool children

BACKGROUND

Subarachnoid hemorrhage evolving with cerebral vasospasm and delayed cerebral ischemia may increase morbidity and mortality. Treating vasospasm with balloon percutaneous angioplasty (PTA) in adults is well known, but data in preschool children are scarce. In addition, the smaller diameters and fragility of the vessels in childhood might lead to serious complications. This study presents two cases of cerebral vasospasm in preschool children treated with balloon PTA. Therefore, it may contribute to a better understanding of the role of that technique as an effective treatment modality in this population.

METHODS

Balloon PTA was performed in two children (3 and 4 year-old) with aneurysmal subarachnoid hemorrhage and delayed cerebral ischemia.

RESULTS

The procedures were uneventful, and both patients survived without complications or new infarction.

CONCLUSIONS

Balloon PTA for proximal vasospasm may improve clinical outcomes in selected pediatric patients. Further studies are needed to clarify the best candidates, materials, and techniques.

Microsurgical clipping of large MCA aneurysm in a 2-month-old child

BACKGROUND

Cerebral aneurysms in children have a low incidence and accounts for less than 4% of all cerebral aneurysms. These aneurysms have been linked to various factors. Severe headache, seizures, and motor-sensory deficits are common presentations.

CASE REPORT

We describe the case of a 2-month-old male patient who presented with generalized tonic-clonic seizures for 4 days. At the hospital, he was stabilized with ventilatory support, sedation, and antiepileptic drugs. A NCCT (Head) showed intraparenchymal hemorrhage in the left fronto-parieto-temporal lobe and subarachnoid hemorrhage. Subsequently a CT angiogram revealed an aneurysm of the left M3 segment of MCA. Successfully, the patient underwent microsurgical clipping of aneurysm and evacuation of hematoma.

CONCLUSIONS

Pediatric cerebral aneurysms differ from their adult counterparts, mainly in their etiology and evolution. As per literature, aneurysmal clipping and neurological endovascular therapy have shown similar results.

Vasospasm in Pediatric Subarachnoid Hemorrhage

Cerebral vasospasm (CV) is a common severe complication of subarachnoid hemorrhage (SAH), a severe type of intracranial bleeding that is uncommon in children. The purpose of this article is to review the current literature regarding this potentially devastating complication. CV may be asymptomatic and is less common in children compared to adults. Several molecular phenomena, including inflammatory ones, contribute to its pathophysiology. Better collateral circulation and higher cerebral blood flow are protective factors in children. When clinically apparent, CV may manifest as a change in the child's neurologic status or vital signs. CV can be diagnosed using brain vessel imaging, such as computed tomography angiography, magnetic resonance angiography, digital subtraction angiography, transcranial Doppler ultrasonography, and computed tomography perfusion. A reduction of < 50% in the artery's caliber confirms the diagnosis. Besides general supportive measures and causative treatment of SAH, CV management options include the administration of calcium channel blockers and neurointerventional approaches, such as intra-arterial vasodilators and balloon angioplasty. Long-term outcomes in children are usually favorable.

Pediatric intracranial aneurysms in a Southern Brazilian population

INTRODUCTION

Intracranial aneurysms are rare in the pediatric population, and their diagnosis can be challenging. They differ from their adult counterparts in several aspects, and hemorrhage is the most common presentation.

OBJECTIVE

To evaluate clinical data, aneurysm characteristics, and therapeutic results in a series of patients younger than 19 years of age with intracranial aneurysms.

METHOD

A retrospective cross-sectional observational study design analyzed medical records and imaging studies. Variables included age, sex, clinical presentation, comorbidities, aneurysmal characteristics, treatment modality, and clinical outcomes.

RESULTS

We identified 15 intracranial aneurysms in 11 patients (6 male), with ages ranging from 3 months to 15 years (mean age 5.2 years). Five patients had associated medical conditions, and hemorrhage was the most frequent clinical presentation (45%). Three patients (27%) had multiple aneurysms, and seven aneurysms were fusiform or dysplastic. The internal carotid artery was the most affected site, involved in 47% of cases. Aneurysm size ranged from 2 to 60 mm (mean 16.8 mm), with giant aneurysms in 27%. Seven patients were treated with endovascular procedures, while three aneurysms were clipped. Symptomatic vasospasm requiring angioplasty occurred in two patients and led to worse outcomes. One patient died due to severe aspiration pneumonia and sepsis that precluded treatment. Good functional outcome (modified Rankin scale - mRS ≤ 2) was achieved in all treated patients (91%).

CONCLUSION

The patients with aneurysms in this series were mostly male, presented mostly hemorrhagic syndromes, and mainly had internal carotid artery involvement. The outcome of treated patients was favorable, regardless of treatment modality.

Closing the Gap in Pediatric Hemorrhagic Stroke: A Systematic Review

Pediatric hemorrhagic stroke (HS) accounts for a large proportion of childhood strokes, 1 of the top 10 causes of pediatric deaths. Morbidity and mortality lead to significant socio-economic and psychosocial burdens. To understand published data on recognizing and managing children with HS, we conducted a systematic review of the literature presented here. We searched PubMed, Embase, CINAHL and the Cochrane Library databases limited to English language and included 174 studies, most conducted in the USA (52%). Terminology used interchangeably for HS included intraparenchymal/intracranial hemorrhage, spontaneous ICH, and cerebrovascular accident (CVA). Key assessments informing prognosis and management included clinical scoring (Glasgow coma scale), and neuroimaging. HS etiologies reported were systemic coagulopathy (genetic, acquired pathologic, or iatrogenic), or focal cerebrovascular lesions (brain arteriovenous malformations, cavernous malformations, aneurysms, or tumor vascularity). Several scales were used to measure outcome: Glasgow outcome score (GOS), Kings outcome score for head injury (KOSCHI), modified Rankin scale (mRS) and pediatric stroke outcome measure (PSOM). Most studies described treatments of at-risk lesions. Few studies described neurocritical care management including raised ICP, seizures, vasospasm, or blood pressure. Predictors of poor outcome included ethnicity, comorbidity, location of bleed, and hematoma &gt;2% of total brain volume. Motor and cognitive outcomes followed independent patterns. Few studies reported on cognitive outcomes, rehabilitation, and transition of care models. Interdisciplinary approach to managing HS is urgently needed, informed by larger cohort studies targeting key clinical question (eg development of a field-guide for the clinician managing patients with HS that is reproducible internationally).

Clinical improvement of a toddler with COVID-19 focal cerebral arteriopathy possibly due to intra-arterial nimodipine

Pediatric stroke is considered an infrequent complication of COVID-19. Focal cerebral arteriopathy (FCA) is one of the most common causes of arterial ischemic stroke in a previously healthy child. The present report describes a toddler with FCA most likely induced by SARS-CoV-2 infection who showed significant clinical improvement that may be related to injection of intra-arterial nimodipine. To our knowledge, this is the first reported use of nimodipine in this setting.

Vasospasm following low-velocity penetrating pediatric intracranial trauma

Background

BB guns or non-powder guns created in the modern era are able to reach exceedingly fast velocities as a result of advances in compressed-gas technology. While missile penetrating trauma has been well documented in neurosurgical literature, penetrating intracranial injury secondary to non-powder guns, along with their associated complications and treatments, is not well described, and even less so in the pediatric population.

Case presentation

Here, we describe an unusual case of a 6-year-old Indigenous child who was accidentally shot with a BB gun to the head. He subsequently developed delayed acute right-sided weakness due to symptomatic vasospasm. His symptoms resolved following hypertensive therapy, balloon angioplasty intervention, and intra-arterial milrinone therapy.

Conclusions

This case highlights the unique complication of delayed symptomatic vasospasm in a child following a non-missile intracranial penetrating injury. Intracranial vasospasm needs to be considered in the presence of delayed neurological deficit given its potential reversibility. This case also emphasizes the importance of gun safety and education when handling and storing these potential weapons around children.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13256-022-03254-5.

Cerebral vasospasm in children with subarachnoid hemorrhage: frequency, diagnosis, and therapeutic management

BACKGROUND

The present study explores the frequency, diagnostic approach, and therapeutic management of cerebral vasospasm in a cohort of children with moderate-to-severe traumatic and nontraumatic subarachnoid hemorrhage (SAH).

METHODS

This was a single-center retrospective study performed over a 10-year period, from January 2010 to December 2019. Children aged from one month to 18 years who were admitted to the pediatric or adult intensive care unit with a diagnosis of SAH were eligible. Cerebral vasospasm could be suspected by clinical signs or transcranial Doppler (TCD) criteria (mean blood flow velocity > 120 cm/s or an increase in mean blood flow velocity by > 50 cm/s within 24 h) and then confirmed on cerebral imaging (with a reduction to less than 50% of the caliber of the cerebral artery).

RESULTS

Eighty patients aged 8.6 years (3.3-14.8 years, 25-75th centiles) were admitted with an initial Glasgow Coma Scale score of 8 (4-12). SAH was nontraumatic in 21 (26%) patients. A total of 14/80 patients (18%) developed cerebral vasospasm on brain imaging on day 6 (5-10) after admission, with a predominance of nontraumatic SAH (12/14). The diagnosis of cerebral vasospasm was suspected on clinical signs and/or significant temporal changes in TCD monitoring (7 patients) and then confirmed on cerebral imaging. Thirteen of 14 patients with vasospasm were successfully treated using a continuous intravenous infusion of milrinone. The Pediatric Cerebral Performance Category score at discharge from the intensive care unit was comparable between children with vasospasm (score of 2 [1-4]) vs. children without vasospasm (score of 4 [2-4]) (p = 0.09).

CONCLUSIONS

These findings indicate that cerebral vasospasm exists in pediatrics, particularly after nontraumatic SAH. The use of TCD and milrinone may help in the diagnostic and therapeutic management of cerebral vasospasm.

Clinical applications of transcranial Doppler in non-trauma critically ill children: a scoping review

BACKGROUND

Many applications of transcranial Doppler (TCD) as a diagnosis or monitoring tool have raised interest in the last decades. It is important that clinicians know when and how to perform TCD in this population, what parameter to assess and monitor and how to interpret it.

OBJECTIVE

This review aims to describe the emerging clinical applications of TCD in critically ill children excluding those suffering from trauma.

METHODS

Databases Web of Science, Cochrane and PubMed were searched in May 2020. We considered all publications since the year 2000 addressing the use of TCD as a prognostic, diagnostic or follow-up tool in children aged 0 to 15 years admitted to intensive care or emergency units, excluding neonatology and traumatic brain injury. Two independent reviewers selected 82 abstracts and full-text articles from the 2011 unique citations identified at the outset.

RESULTS

TCD provides crucial additional information at bedside about cerebrovascular hemodynamics. Many clinical applications include the diagnosis and management of various medical and surgical neurologic conditions (central nervous system infections, arterial ischemic stroke, subarachnoid hemorrhage and vasospasm, brain death, seizures, metabolic disease, hydrocephalus) as well as monitoring the impact systemic conditions on brain perfusion (hemodynamic instability, circulatory assistance).

CONCLUSION

To conclude, TCD has become an invaluable asset for non-invasive neuromonitoring in critically ill children excluding those suffering from trauma. However, the scope of TCD remains unclearly defined yet and reference values in critically ill children are still lacking.

Intracranial aneurysms in pediatric population: a two-center audit

OBJECTIVE

Intracranial aneurysms (IA) in children are rare, accounting for less than 5% of all IA. Due to their scarcity, the epidemiology is poorly understood and differs from adults in term of clinical presentation, size, location, and origin. Consequently, the treatment strategies are specific and cannot be only based on data from adult series. The aim of our study was to report the characteristics, management, and outcomes of children treated for IA in two university hospitals located in Normandy (France) over the last 17 years and to perform a literature review of this rare pathology.

METHODS

This retrospective study included 18 consecutive children (< 18 years old) admitted with cerebral aneurysm treated in two neurosurgery departments in Normandy, from 2001 to 2018. Computerized tomography and cerebral angiography established the diagnosis. Both endovascular and surgical procedures were discussed in all cases. Data focused on clinical condition at admission, characteristics of the IA, choice of the treatment modalities, and complications. The outcome at follow-up is based on Glasgow outcomes scale (GOS) at 1 year.

RESULTS

During the study period, 18 children (mean age: 12.6 years; sex ratio male/female: 2.3) were admitted with 21 IA. Aneurysms had a mean size of 13.6 mm with 4 giant aneurysms and were mostly located in the anterior circulation (16/21). Clinical presentations at onset were sudden symptoms related to a subarachnoid hemorrhage in 13 patients, headaches in 4 patients with giant aneurysm, and asymptomatic in one patient. Among the 13 patients with ruptured IA, 6 presented in poor preoperative condition (Hunt and Hess Grade ≥ 4). Treatment modalities consisted in embolization in 9 patients and surgery in 9 patients including 2 by-pass surgeries in fusiform aneurysms. Complications were similar in the two groups, but two cases of recanalization were observed in the endovascular group. At 1 year of follow-up, 14 children were in good condition (GOS Score > 4) and one died. Three children presented associated IA treated by the same technique as initial aneurysm.

CONCLUSIONS

Pediatric aneurysm is a different pathology compared with adults, occurring more frequently in male population with a higher proportion of giant aneurysms and aneurysms located in the internal carotid bifurcation. The use of endovascular techniques has progressed in the last years, but surgery was proposed for half of our population.

Treatment of Increased Intracranial Pressure and Vasospasm after Subarachnoid Hemorrhage in a 9-Year-Old Child—A Case Report

In this article, we reported a 9-year-old male child patient who suffered severe subarachnoid hemorrhage due to ruptured dissecting aneurysm of the left parieto-occipital artery. After endovascular occlusion of the aneurysm, increased intracranial pressure refractory to noninvasive therapy required secondary decompressive hemicraniectomy. Critical vasospasm and delayed neurological deterioration were treated by oral nimodipine and successful endovascular rescue therapy consisting of intra-arterial balloon dilatation.

Microsurgery for a ruptured intracranial aneurysm in a 3-year-old child: A case report

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Intracranial aneurysms are rare in children, only case reports and case series published.

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Subarachnoid hemorrhage is the most common feature of pediatric intracranial aneurysm with good clinical grade.

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Microsurgical clipping is safe and effective in treatment of pediatric intracranial aneurysms.

Introduction

Pediatric intracranial aneurysms are rare, with some different characteristics from those in adults. Here, we present a case of distal anterior cerebral artery aneurysm which we believe the first case from Vietnam.

Presentation of case

A 3 years old boy presented with headache, lethargic and hemiparesis was diagnosed ruptured distal anterior cerebral artery aneurysm with CTA. 10 days before admission in our hospital, the toddler was admitted in local hospital with diagnosis of SAH without more accurate findings. Clipping microsurgery of aneurysms with left interhemispheric approach was done with good outcome.

Discussion

The epidermiology, presentation and diagnosis and strategy of treatments as well as their outcomes were discussed. We also discussed our thoughts about our case within the limited-resource condition such as in Vietnam.

Conclusion

Pediatric intracranial anerusyms are rare but should be recognised in neurosurgical practice. Surgery is an effective treatment method.

Transcranial Doppler Ultrasound During Critical Illness in Children: Survey of Practices in Pediatric Neurocritical Care Centers

OBJECTIVES

The scope of transcranial Doppler ultrasound in the practice of pediatric neurocritical care is unknown. We have surveyed pediatric neurocritical care centers on their use of transcranial Doppler and analyzed clinical management practices.

DESIGN

Electronic-mail recruitment with survey of expert centers using web-based questionnaire.

SETTING

Survey of 43 hospitals (31 United States, 12 international) belonging to the Pediatric Neurocritical Care Research Group.

PATIENTS

None.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A 67% (29/43) hospital-response rate. Of these centers, 27 reported using transcranial Doppler in the PICU; two hospitals opted out due to lack of transcranial Doppler availability/use. The most common diagnoses for using transcranial Doppler in clinical care were intracranial/subarachnoid hemorrhage (20 hospitals), arterial ischemic stroke (14 hospitals), and traumatic brain injury (10 hospitals). Clinical studies were carried out and interpreted by credentialed individuals in 93% (25/27) and 78% (21/27) of the centers, respectively. A written protocol for performance of transcranial Doppler in the PICU was available in 30% (8/27 hospitals); of these, two of eight hospitals routinely performed correlation studies to validate results. In 74% of the centers (20/27), transcranial Doppler results were used to guide clinical care: that is, when to obtain a neuroimaging study (18 hospitals); how to manipulate cerebral perfusion pressure with fluids/vasopressors (13 hospitals); and whether to perform a surgical intervention (six hospitals). Research studies were also commonly performed for a range of diagnoses.

CONCLUSIONS

At least 27 pediatric neurocritical care centers use transcranial Doppler during clinical care. In the majority of centers, studies are performed and interpreted by credentialed personnel, and findings are used to guide clinical management. Further studies are needed to standardize these practices.

Cerebral Vasospasm after Open Fenestration of an Arachnoid Cyst in a 4-Year-Old Boy: Case Report and Review of the Literature

Cerebral vasospasm is associated with significant morbidity, and most commonly occurs following subarachnoid hemorrhage. Rarely, vasospasm can follow tumor resection and traumatic brain injury. We present the first reported case of a young child who developed diffuse vasospasm following open fenestration of an arachnoid cyst and was promptly treated, with full recovery of neurologic function. Although vasopasm after arachnoid cyst fenestration is rare, it can be included in the differential for a new focal neurologic deficit.

Emergency Neurological Life Support: Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) is a subset of stroke due to spontaneous bleeding within the parenchyma of the brain. It is potentially lethal, and survival depends on ensuring an adequate airway, proper diagnosis, and early management of several specific issues such as blood pressure, coagulopathy reversal, and surgical hematoma evacuation for appropriate patients. ICH was chosen as an Emergency Neurological Life Support (ENLS) protocol because intervention within the first hours may improve outcome, and it is critical to have site-specific protocols to drive care quickly and efficiently.

Glutamine combined with pantoprazole for prevention of stress ulcer in patients with thalamic hemorrhage: Impact on prognosis

AIM

To investigate the effect of glutamine combined with pantoprazole on the incidence of stress ulcer and prognosis in patients with thalamic hemorrhage.

METHODS

The clinical data of 130 patients with thalamic hemorrhage treated at the Ningbo Yinzhou Second Hospital from May 2012 to May 2017 were retrospectively analyzed, of whom 60 were given pantoprazole to prevent stress ulcer (control group) and 70 were given glutamine and pantoprazole (observation group). Gastric juice pH value, plasma adreno-cortico-tropic-hormone (ACTH), cortisol (Cor), the incidence of stress ulcer, bleeding duration, and mortality were compared between the two groups.

RESULTS

One week after treatment, the pH value of gastric juice in the observation group was significantly higher than that in the control group (5.19 ± 0.81 vs 3.03 ± 0.91, P < 0.05), and the concentrations of plasma ACTH and Cor in the observation group were significantly lower than those in the control group (18.68 ± 1.56 vs 25.22 ± 2.58 and 431.5 ± 213.1 vs 579.9 ± 209.6, respectively; P < 0.05). At 2 wk after treatment, the pH value of gastric juice in the observation group was significantly higher than that in the control group (5.12 ± 0.87 vs 2.92 ± 0.93, P < 0.05), and plasma concentrations of ACTH and Cor in the observation group were significantly lower than those of the control group (17.32 ± 1.41 vs 25.31 ± 2.61 and 423.9 ± 203.6 vs 531.8 ± 210.7, respectively, P < 0.05). The incidence of stress ulcer, duration of bleeding, and mortality in the observation group were significantly lower than those of the control group (14.29% vs 31.67%, 2.56 ± 1.89 vs 5.38 ± 2.07, and 11.43% vs 21.67%, respectively; P < 0.05).

CONCLUSION

The application of glutamine combined with pantoprazole in patients with thalamic hemorrhage can prevent the occurrence of stress ulcer and improve the prognosis of patients.

Emergency Neurological Life Support: Intracerebral Hemorrhage

Intracerebral hemorrhage (ICH) is a subset of stroke due to bleeding within the parenchyma of the brain. It is potentially lethal, and survival depends on ensuring an adequate airway, reversal of coagulopathy, and proper diagnosis. ICH was chosen as an Emergency Neurological Life Support protocol because intervention within the first critical hour may improve outcome, and it is critical to have site-specific protocols to drive care quickly and efficiently.

Effects of simvastatin and taurine on delayed cerebral vasospasm following subarachnoid hemorrhage in rabbits

The aim of the current study was to observe the effects of simvastatin and taurine on delayed cerebral vasospasm (DCVS) following experimental subarachnoid hemorrhage (SAH) in rabbits. A total of 48 New Zealand white rabbits were allocated at random into four groups (control, SAH, SAH + simvastatin and SAH + taurine groups; n=12 each). The rabbit model of DCVS was established using a double hemorrhage method, which involved injecting autologous arterial blood into the cisterna magna in the SAH groups. The SAH + simvastatin group was administered oral simvastatin (5 mg/kg) daily between days 0-6. The SAH + taurine group was administered oral taurine (50 mg/kg) daily between days 0-6. Starch (50 mg/kg) was administered orally to the animals in the other two groups (control and SAH groups). The control group were not subjected to any other injections or treatment. The internal diameter and internal diameter/wall thickness of the basilar artery (BA) were measured. The expression levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6 were determined using immunohistochemical and quantitative polymerase chain reaction methods following the sacrifice of all animals on day 7. The activity of nuclear factor (NF)-κB in the BA was also measured using an electrophoretic mobility shift assay. The BA walls in the SAH + simvastatin and SAH + taurine groups exhibited reduced narrowing and corrugation of the tunica elastica interna compared with the SAH group. At the protein and cDNA levels, it was found that cerebral vasospasm of the BA in the SAH + simvastatin and SAH + taurine groups was alleviated, as indicated by the reduced expression of TNF-α, IL-1β, IL-6 and NF-κB compared with the SAH group (P<0.05). In conclusion, simvastatin and taurine reduced DCVS following SAH in rabbits, which suggests that these compounds may exert anti-inflammatory effects.