Relative importance of hypertension compared with hypervolemia for increasing cerebral oxygenation in patients with cerebral vasospasm after subarachnoid hemorrhage

Intraoperative goal-directed fluid therapy in adult patients undergoing craniotomies under general anaesthesia: A systematic review and meta-analysis with trial sequential analysis

Background and Aims

Goal-directed fluid therapy (GDFT) has conflicting evidence regarding outcomes in neurosurgical patients. This meta-analysis aimed to compare the effect of GDFT and conventional fluid therapy on various perioperative outcomes in patients undergoing neurosurgical procedures.

Methods

A comprehensive literature search was conducted using PubMed, EMBASE, Scopus, ProQuest, Web of Science, EBSCOhost, Cochrane and preprint servers. The search was conducted up until 16 October 2023, following PROSPERO registration. The search strategy included terms related to GDFT, neurosurgery and perioperative outcomes. Only randomised controlled trials involving adult humans and comparing GDFT with standard/liberal/traditional/restricted fluid therapy were included. The studies were evaluated for risk of bias (RoB), and pooled estimates of the outcomes were measured in terms of risk ratio (RR) and mean difference (MD).

Results

No statistically significant difference was observed in neurological outcomes between GDFT and conventional fluid therapy [RR with 95% confidence interval (CI) was 1.10 (0.69, 1.75), two studies, 90 patients, low certainty of evidence using GRADEpro]. GDFT reduced postoperative complications [RR = 0.67 (0.54, 0.82), six studies, 392 participants] and intensive care unit (ICU) and hospital stay [MD (95% CI) were -1.65 (-3.02, -0.28) and -0.94 (-1.47, -0.42), respectively] with high certainty of evidence. The pulmonary complications were significantly lower in the GDFT group [RR (95% CI) = 0.55 (0.38, 0.79), seven studies, 442 patients, high certainty of evidence]. Other outcomes, including total intraoperative fluids administered and blood loss, were comparable in GDFT and conventional therapy groups [MD (95% CI) were -303.87 (-912.56, 304.82) and -14.79 (-49.05, 19.46), respectively].

Conclusion

The perioperative GDFT did not influence the neurological outcome. The postoperative complications and hospital and ICU stay were significantly reduced in the GDFT group.

Diagnosis and management of subarachnoid haemorrhage

Aneurysmal subarachnoid haemorrhage (aSAH) presents a challenge to clinicians because of its multisystem effects. Advancements in computed tomography (CT), endovascular treatments, and neurocritical care have contributed to declining mortality rates. The critical care of aSAH prioritises cerebral perfusion, early aneurysm securement, and the prevention of secondary brain injury and systemic complications. Early interventions to mitigate cardiopulmonary complications, dyselectrolytemia and treatment of culprit aneurysm require a multidisciplinary approach. Standardised neurological assessments, transcranial doppler (TCD), and advanced imaging, along with hypertensive and invasive therapies, are vital in reducing delayed cerebral ischemia and poor outcomes. Health care disparities, particularly in the resource allocation for SAH treatment, affect outcomes significantly, with telemedicine and novel technologies proposed to address this health inequalities. This article underscores the necessity for comprehensive multidisciplinary care and the urgent need for large-scale studies to validate standardised treatment protocols for improved SAH outcomes.

The Role of Brain Tissue Oxygenation Monitoring in the Management of Subarachnoid Hemorrhage: A Scoping Review

Monitoring of brain tissue oxygenation (PbtO2) is an important component of multimodal monitoring in traumatic brain injury. Over recent years, use of PbtO2 monitoring has also increased in patients with poor-grade subarachnoid hemorrhage (SAH), particularly in those with delayed cerebral ischemia. The aim of this scoping review was to summarize the current state of the art regarding the use of this invasive neuromonitoring tool in patients with SAH. Our results showed that PbtO2 monitoring is a safe and reliable method to assess regional cerebral tissue oxygenation and that PbtO2 represents the oxygen available in the brain interstitial space for aerobic energy production (i.e., the product of cerebral blood flow and the arterio-venous oxygen tension difference). The PbtO2 probe should be placed in the area at risk of ischemia (i.e., in the vascular territory in which cerebral vasospasm is expected to occur). The most widely used PbtO2 threshold to define brain tissue hypoxia and initiate specific treatment is between 15 and 20 mm Hg. PbtO2 values can help identify the need for or the effects of various therapies, such as hyperventilation, hyperoxia, induced hypothermia, induced hypertension, red blood cell transfusion, osmotic therapy, and decompressive craniectomy. Finally, a low PbtO2 value is associated with a worse prognosis, and an increase of the PbtO2 value in response to treatment is a marker of good outcome.

Hemodynamic Management in the Prevention and Treatment of Delayed Cerebral Ischemia After Aneurysmal Subarachnoid Hemorrhage

One of the most serious complications after subarachnoid hemorrhage (SAH) is delayed cerebral ischemia, the cause of which is multifactorial. Delayed cerebral ischemia considerably worsens neurological outcome and increases the risk of death. The targets of hemodynamic management of SAH have widely changed over the past 30 years. Hypovolemia and hypotension were favored prior to the era of early aneurysmal surgery but were subsequently replaced by the use of hypervolemia and hypertension. More recently, the concept of goal-directed therapy targeting euvolemia, with or without hypertension, is gaining preference. Despite the evolving concepts and the vast literature, fundamental questions related to hemodynamic optimization and its effects on cerebral perfusion and patient outcomes remain unanswered. In this review, we explain the rationale underlying the approaches to hemodynamic management and provide guidance on contemporary strategies related to fluid administration and blood pressure and cardiac output manipulation in the management of SAH.

Prevention and Correction of Dysnatremia After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Dysnatremia occurs commonly in patients with aneurysmal subarachnoid hemorrhage (aSAH). The mechanisms for development of sodium dyshomeostasis are complex, including the cerebral salt-wasting syndrome, the syndrome of inappropriate secretion of antidiuretic hormone, diabetes insipidus. Iatrogenic occurrence of altered sodium levels plays a role, as sodium homeostasis is tightly linked to fluid and volume management.

METHODS

Narrative review of the literature.

RESULTS

Many studies have aimed to identify factors predictive of the development of dysnatremia, but data on associations between dysnatremia and demographic and clinical variables are variable. Furthermore, although a clear relationship between serum sodium serum concentrations and outcomes has not been established-poor outcomes have been associated with both hyponatremia and hypernatremia in the immediate period following aSAH and set the basis for seeking interventions to correct dysnatremia. While sodium supplementation and mineralocorticoids are frequently administered to prevent or counter natriuresis and hyponatremia, evidence to date is insufficient to gauge the effect of such treatment on outcomes.

CONCLUSIONS

In this article, we reviewed available data and provide a practical interpretation of these data as a complement to the newly issued guidelines for management of aSAH. Gaps in knowledge and future directions are discussed.

Non-Convulsive Status Epilepticus in Aneurysmal Subarachnoid Hemorrhage: A Prognostic Parameter

A non-convulsive status epilepticus (ncSE) is a potentially fatal complication for patients in neurointensive care. In patients with aneurysmal subarachnoid hemorrhage (SAH), ncSE remains scarcely investigated. In this study, we aim to investigate the frequency and influence of non-convulsive status epilepticus on outcome in patients with SAH. We retrospectively analyzed data of consecutive patients with aneurysmal subarachnoid hemorrhage and evaluated clinical, radiological, demographical and electroencephalogram (EEG) data. Outcome was assessed according to the modified Rankin Scale (mRS) at 6 months and stratified into favorable (mRS 0-2) vs. unfavorable (mRS 3-6). We identified 171 patients with SAH, who received EEG between 01/2012 and 12/2020. ncSE was diagnosed in 19 patients (3.7%), only one of whom achieved favorable outcome. The multivariate regression analysis revealed four independent predictors of unfavorable outcome: presence of ncSE (p = 0.003; OR 24.1; 95 CI% 2.9-195.3), poor-grade SAH (p < 0.001; OR 14.0; 95 CI% 8.5-23.1), age (p < 0.001; OR 2.8; 95 CI% 1.6-4.6) and the presence of DIND (p < 0.003; OR 1.9; 95 CI% 1.2-3.1) as independent predictors for unfavorable outcome. According to our study, development of ncSE in patients suffering SAH might correlate with poor prognosis. Even when medical treatment is successful and no EEG abnormalities are detected, the long-term outcome remains poor.

Early Serum Creatinine Levels after Aneurysmal Subarachnoid Hemorrhage Predict Functional Neurological Outcome after 6 Months

Acute kidney injury (AKI) is a known predictor of unfavorable outcome in patients treated at the ICU, irrespective of the disease. However, data on the potential influence of serum creatinine (sCr) on hospital admission on the outcome in patients suffering from aneurysmal subarachnoid hemorrhage (SAH) is scarce. A total of 369 consecutive patients suffering from SAH were included in this retrospective cohort study. Patients were divided into good-grade (WFNS I−III) versus poor-grade (WFNS IV−V). Outcome was assessed according to the modified Rankin Scale (mRS) after 6 months and stratified into favorable (mRS 0−2) versus unfavorable (mRS 3−6). SAH patients with sCr levels <1.0 mg/dL achieved significantly a favorable outcome more often compared to patients with sCr levels ≥1.0 mg/dL (p = 0.003). In the multivariable analysis, higher levels of sCr (p = 0.014, OR 2.4; 95% CI 1.2−4.7), poor-grade on admission (p < 0.001, OR 9.8; 95% CI 5.6−17.2), age over 65 years (p < 0.001, OR 3.3; 95% CI 1.7−6.1), and delayed cerebral ischemia (p < 0.001, OR 7.9; 95% CI 3.7−17.1) were independently associated with an unfavorable outcome. We identified increased sCr on admission as a predictor for unfavorable functional outcome after SAH. Further studies elucidating the pathophysiology of this association are necessary.

Hemodynamic response and clinical outcome following intravenous milrinone plus norepinephrine-based hyperdynamic hypertensive therapy in patients suffering secondary cerebral ischemia after aneurysmal subarachnoid hemorrhage

Purpose

Intravenous and intra-arterial milrinone as a rescue measure for delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (SAH) has been adopted by several groups, but so far, evidence for the clinical benefit is unclear and effect on brain perfusion is unknown. The aim of the actual analysis was to define cerebral hemodynamic effects and outcome of intravenous milrinone plus norepinephrine supplemented by intra-arterial nimodipine as a rescue strategy for DCI following aneurysmal SAH.

Methods

Of 176 patients with aneurysmal SAH treated at our neurosurgical department between April 2016 and March 2021, 98 suffered from DCI and were submitted to rescue therapy. For the current analysis, characteristics of these patients and clinical response to rescue therapy were correlated with hemodynamic parameters, as assessed by CT angiography (CTA) and perfusion CT. Time to peak (TTP) delay in the ischemic focus and the volume with a TTP delay of more than 4 s (T4 volume) were used as hemodynamic parameters.

Results

The median delay to neurological deterioration following SAH was 5 days. Perfusion CT at that time showed median T4 volumes of 40 cc and mean focal TTP delays of 2.5 ± 2.1 s in these patients. Following rescue therapy, median T4 volume decreased to 10 cc and mean focal TTP delay to 1.7 ± 1.9 s. Seventeen patients (17% of patients with DCI) underwent additional intra-arterial spasmolysis using nimodipine. Visible resolution of macroscopic vasospasm on CTA was observed in 43% patients with DCI and verified vasospasm on CTA, including those managed with additional intra-arterial spasmolysis. Initial WFNS grade, occurrence of secondary infarction, ischemic volumes and TTP delays at the time of decline, the time to clinical decline, and the necessity for additional intra-arterial spasmolysis were identified as the most important features determining neurological outcome at 6 months.

Conclusion

The current analysis shows that cerebral perfusion in the setting of secondary cerebral ischemia following SAH is measurably improved by milrinone and norepinephrine–based hyperdynamic therapy. A long-term clinical benefit by the addition of milrinone appears likely. Separation of the direct effect of milrinone from the effect of induced hypertension is not possible based on the present dataset.

Hemodynamic Monitoring in Patients With Subarachnoid Hemorrhage: A Systematic Review and Meta-Analysis

Aneurysmal subarachnoid hemorrhage (aSAH) often causes cardiopulmonary dysfunction. Therapeutic strategies can be guided by standard (invasive arterial/central venous pressure measurements, fluid balance assessment), and/or advanced (pulse index continuous cardiac output, pulse dye densitometry, pulmonary artery catheterization) hemodynamic monitoring. We conducted a systematic review and meta-analysis of the literature to determine whether standard compared with advanced hemodynamic monitoring can improve patient management and clinical outcomes after aSAH. A literature search was performed for articles published between January 1, 2000 and January 1, 2019. Studies involving aSAH patients admitted to the intensive care unit and subjected to any type of hemodynamic monitoring were included. A total of 14 studies were selected for the qualitative synthesis and 3 randomized controlled trials, comparing standard versus advanced hemodynamic monitoring, for meta-analysis. The incidence of delayed cerebral ischemia was lower in the advanced compared with standard hemodynamic monitoring group (relative risk [RR]=0.71, 95% confidence interval [CI]=0.52-0.99; P=0.044), but there were no differences in neurological outcome (RR=0.83, 95% CI=0.64-1.06; P=0.14), pulmonary edema onset (RR=0.44, 95% CI=0.05-3.92; P=0.46), or fluid intake (mean difference=-169 mL; 95% CI=-1463 to 1126 mL; P=0.8) between the 2 groups. In summary, this systematic review and meta-analysis found only low-quality evidence to support the use of advanced hemodynamic monitoring in selected aSAH patients. Because of the small number and low quality of studies available for inclusion in the review, further studies are required to investigate the impact of standard and advanced hemodynamic monitoring-guided management on aSAH outcomes.

Vitamin K Antagonist (Phenprocoumon) and Subarachnoid Hemorrhage: A Single-Center, Matched-Pair Analysis

BACKGROUND

Demographic changes are leading to an aging society with a growing number of patients relying on anticoagulation, and vitamin K antagonists (VKA) are still widely used. As mortality and functional outcomes are worse in case of VKA-associated hemorrhagic stroke, phenprocoumon treatment seems to be a negative prognostic factor in case of subarachnoid hemorrhage (SAH). The purpose of this study was to analyze whether phenprocoumon treatment does worsen the outcome after non-traumatic SAH.

METHODS

All patients treated for non-traumatic SAH between January 2007 and December 2016 in our institution were retrospectively analyzed. After exclusion of patients with anticoagulant or antiplatelet treatment other than phenprocoumon, we analyzed 1040 patients. Thirty-three patients (3%) of those were treated with continuous phenprocoumon. In total, 132 out of all 1007 patients without anticoagulant treatment of the remaining patients were matched as control group (ratio = 1:4).

RESULTS

Patients with phenprocoumon treatment were significantly older (66.5 years vs. 53.9 years; p < .0001), and admission status was significantly more often poor (66.7% vs. 41.8%, p = .007) compared to all patients without anticoagulant treatment. Further, bleeding pattern and rates of early hydrocephalus did not differ. Matched-pair analysis revealed a significant higher rate of angio-negative SAH in the study group (p = .001). Overall rates of hemorrhagic or thromboembolic complications did not differ (21.4% vs. 18.8%; NS) but were more often fatal, and 30-day mortality rate was significantly higher in the phenprocoumon group than in patients of the matched-pair control group (33% vs. 24%; p < .001). 30% of the phenprocoumon group and 37% of the matched-pair control group reached favorable outcome. However, poor outcome was strong associated with the reason for phenprocoumon treatment.

CONCLUSION

Patients with phenprocoumon treatment at the time of SAH are significantly older, admission status is worse, and 30-day mortality rates are significantly higher compared to patients without anticoagulant treatment. However, outcome at 6 months did not differ to the matched-pair control group but seems to be strongly associated with the underlying cardiovascular disease. Treatment of these patients is challenging and should be performed on an interdisciplinary base in each individual case. Careful decision-making regarding discontinuation and bridging of anticoagulation and close observation is mandatory.

Aneurysmal Subarachnoid Hemorrhage: Review of the Pathophysiology and Management Strategies

PURPOSE OF REVIEW

Aneurysmal subarachnoid hemorrhage remains a devastating disease process despite medical advances made over the past 3 decades. Much of the focus was on prevention and treatment of vasospasm to reduce delayed cerebral ischemia and improve outcome. In recent years, there has been a shift of focus onto early brain injury as the precursor to delayed cerebral ischemia. This review will focus on the most recent data surrounding the pathophysiology of aneurysmal subarachnoid hemorrhage and current management strategies.

RECENT FINDINGS

There is a paucity of successful trials in the management of subarachnoid hemorrhage likely related to the targeting of vasospasm. Pathophysiological changes occurring at the time of aneurysmal rupture lead to early brain injury including cerebral edema, inflammation, and spreading depolarization. These events result in microvascular collapse, vasospasm, and ultimately delayed cerebral ischemia. Management of aneurysmal subarachnoid hemorrhage has remained the same over the past few decades. No recent trials have resulted in new treatments. However, our understanding of the pathophysiology is rapidly expanding and will advise future therapeutic targets.

Invasive Multimodal Neuromonitoring in Aneurysmal Subarachnoid Hemorrhage: A Systematic Review

BACKGROUND AND PURPOSE

Aneurysmal subarachnoid hemorrhage is a devastating disease leaving surviving patients often severely disabled. Delayed cerebral ischemia (DCI) has been identified as one of the main contributors to poor clinical outcome after subarachnoid hemorrhage. The objective of this review is to summarize existing clinical evidence assessing the diagnostic value of invasive neuromonitoring (INM) in detecting DCI and provide an update of evidence since the 2014 consensus statement on multimodality monitoring in neurocritical care.

METHODS

Three invasive monitoring techniques were targeted in the data collection process: brain tissue oxygen tension (p_tiO₂), cerebral microdialysis, and electrocorticography. Prospective and retrospective studies as well as case series (≥10 patients) were included as long as monitoring was used to detect DCI or guide DCI treatment.

RESULTS

Forty-seven studies reporting INM in the context of DCI were included (p_tiO₂: N=21; cerebral microdialysis: N=22; electrocorticography: N=4). Changes in brain oxygen tension are associated with angiographic vasospasm or reduction in regional cerebral blood flow. Metabolic monitoring with trend analysis of the lactate to pyruvate ratio using cerebral microdialysis, identifies patients at risk for DCI. Clusters of cortical spreading depolarizations are associated with clinical neurological worsening and cerebral infarction in selected patients receiving electrocorticography monitoring.

CONCLUSIONS

Data supports the use of INM for the detection of DCI in selected patients. Generalizability to all subarachnoid hemorrhage patients is limited by design bias of available studies and lack of randomized trials. Continuous data recording with trend analysis and the combination of INM modalities can provide tailored treatment support in patients at high risk for DCI. Future trials should test interventions triggered by INM in relation to cerebral infarctions.

Cerebral Autoregulation in Subarachnoid Hemorrhage

Subarachnoid hemorrhage (SAH) is a devastating stroke subtype with a high rate of mortality and morbidity. The poor clinical outcome can be attributed to the biphasic course of the disease: even if the patient survives the initial bleeding emergency, delayed cerebral ischemia (DCI) frequently follows within 2 weeks time and levies additional serious brain injury. Current therapeutic interventions do not specifically target the microvascular dysfunction underlying the ischemic event and as a consequence, provide only modest improvement in clinical outcome. SAH perturbs an extensive number of microvascular processes, including the “automated” control of cerebral perfusion, termed “cerebral autoregulation.” Recent evidence suggests that disrupted cerebral autoregulation is an important aspect of SAH-induced brain injury. This review presents the key clinical aspects of cerebral autoregulation and its disruption in SAH: it provides a mechanistic overview of cerebral autoregulation, describes current clinical methods for measuring autoregulation in SAH patients and reviews current and emerging therapeutic options for SAH patients. Recent advancements should fuel optimism that microvascular dysfunction and cerebral autoregulation can be rectified in SAH patients.

Goal-directed Fluid Therapy Versus Conventional Fluid Therapy During Craniotomy and Clipping of Cerebral Aneurysm: A Prospective Randomized Controlled Trial

BACKGROUND

Fluid imbalance is common after aneurysmal subarachnoid hemorrhage and negatively impacts clinical outcomes. We compared intraoperative goal-directed fluid therapy (GDFT) using left ventricular outflow tract velocity time integral (LVOT-VTI) measured by transesophageal echocardiography with central venous pressure (CVP)-guided fluid therapy during aneurysm clipping in aneurysmal subarachnoid hemorrhage patients.

METHODS

Fifty adults scheduled for urgent craniotomy for aneurysm clipping were randomly allocated to 2 groups: group G (n=25) received GDFT guided by LVOT-VTI and group C (n=25) received CVP-guided fluid management. The primary outcome was intraoperative mean arterial pressure (MAP). Secondary outcomes included volume of fluid administered and several other intraoperative and postoperative variables, including neurological outcome at hospital discharge and at 30 and 90 days.

RESULTS

There was no difference in MAP between the 2 groups despite patients in group G receiving lower volumes of fluid compared with patients in group C (2503.6±534.3 vs. 3732.8±676.5 mL, respectively; P<0.0001). Heart rate and diastolic blood pressure were also comparable between groups, whereas systolic blood pressure was higher in group G than in group C at several intraoperative time points. Other intraoperative variables, including blood loss, urine output, and lactate levels were not different between the 2 groups. Postoperative variables, including creatinine, duration of postoperative mechanical ventilation, length of intensive care unit and hospital stay, and incidence of acute kidney injury, pneumonitis, and vasospasm were also comparable between groups. There was no difference in neurological outcome at hospital discharge (modified Rankin scale) and at 30 and 90 days (Extended Glasgow Outcome Scale) between the 2 groups.

CONCLUSION

Compared with CVP-guided fluid therapy, transesophageal echocardiography-guided GDFT maintains MAP with lower volumes of intravenous fluid in patients undergoing clipping of intracranial aneurysms with no adverse impact on postoperative complications.

Intravenous milrinone for treatment of delayed cerebral ischaemia following subarachnoid haemorrhage: a pooled systematic review

Small trials have demonstrated promising results utilising intravenous milrinone for the treatment of delayed cerebral ischaemia (DCI) after subarachnoid haemorrhage (SAH). Here we summarise and contextualise the literature and discuss the future directions of intravenous milrinone for DCI. A systematic, pooled analysis of literature was performed in accordance with the PRISMA statement. Methodological rigour was analysed using the MINORS criteria. Extracted data included patient population; treatment protocol; and clinical, radiological, and functional outcome. The primary outcome was clinical resolution of DCI. Eight hundred eighteen patients from 10 single-centre, observational studies were identified. Half (n = 5) of the studies were prospective and all were at high risk of bias. Mean age was 52 years, and females (69%) outnumbered males. There was a similar proportion of low-grade (WFNS 1-2) (49.7%) and high-grade (WFNS 3-5) (50.3%) SAH. Intravenous milrinone was administered to 523/818 (63.9%) participants. Clinical resolution of DCI was achieved in 375/424 (88%), with similar rates demonstrated with intravenous (291/330, 88%) and combined intra-arterial-intravenous (84/94, 89%) therapy. Angiographic response was seen in 165/234 (71%) receiving intravenous milrinone. Hypotension (70/303, 23%) and hypokalaemia (31/287, 11%) were common drug effects. Four cases (0.5%) of drug intolerance occurred. Good functional outcome was achieved in 271/364 (74%) patients. Cerebral infarction attributable to DCI occurred in 47/250 (19%), with lower rates in asymptomatic spasm. Intravenous milrinone is a safe and feasible therapy for DCI. A signal for efficacy is demonstrated in small, low-quality trials. Future research should endeavour to establish the optimal protocol and dose, prior to a phase-3 study.

Aneurysmal subarachnoid hemorrhage during pregnancy: a comprehensive and systematic review of the literature

Aneurysmal subarachnoid hemorrhage (aSAH) is an emergent condition requiring rapid intervention and prolonged monitoring. There are few recommendations regarding the management of aSAH in pregnancy. We identified all available literature and compiled management decisions as well as reported outcomes through a systematic literature review without meta-analysis to provide recommendations for management of aSAH during pregnancy. We included a total of 23 articles containing 54 cases of pregnancy-related aSAH in our review. From these reports and other literature, we evaluated information on aSAH pathophysiology, diagnosis, and management with respect to pregnancy. Early transfer to an appropriate facility with neurocritical care, a high-risk obstetric service, and a neurosurgery team available is crucial for the management of aSAH in pregnancy. Intensive monitoring and a multidisciplinary approach remain fundamental to ensure maternal and fetal health.

Neurovascular disease, diagnosis, and therapy: Subarachnoid hemorrhage and cerebral vasospasm

The worldwide incidence of spontaneous subarachnoid hemorrhage is about 6.1 per 100,000 cases per year (Etminan et al., 2019). Eighty-five percent of cases are due to intracranial aneurysms. The mean age of those affected is 55 years, and two-thirds of the patients are female. The prognosis is related mainly to the neurologic condition after the subarachnoid hemorrhage and the age of the patient. Overall, 15% of patients die before reaching the hospital, another 20% die within 30 days, and overall 75% are dead or remain disabled. Case fatality has declined by 17% over the last 3 decades. Despite the improvement in outcome probably due to improved diagnosis, early aneurysm repair, administration of nimodipine, and advanced intensive care support, the outcome is not very good. Even among survivors, 75% have permanent cognitive deficits, mood disorders, fatigue, inability to return to work, and executive dysfunction and are often unable to return to their premorbid level of functioning. The key diagnostic test is computed tomography, and the treatments that are most strongly supported by scientific evidence are to undertake aneurysm repair in a timely fashion by endovascular coiling rather than neurosurgical clipping when feasible and to administer enteral nimodipine. The most common complications are aneurysm rebleeding, hydrocephalus, delayed cerebral ischemia, and medical complications (fever, anemia, and hyperglycemia). Management also probably is optimized by neurologic intensive care units and multidisciplinary teams.

The Updated Role of the Blood Brain Barrier in Subarachnoid Hemorrhage: From Basic and Clinical Studies

Subarachnoid hemorrhage (SAH) is a type of hemorrhagic stroke associated with high mortality and morbidity. The blood-brain-barrier (BBB) is a structure consisting primarily of cerebral microvascular endothelial cells, end feet of astrocytes, extracellular matrix, and pericytes. Post-SAH pathophysiology included early brain injury and delayed cerebral ischemia. BBB disruption was a critical mechanism of early brain injury and was associated with other pathophysiological events. These pathophysiological events may propel the development of secondary brain injury, known as delayed cerebral ischemia. Imaging advancements to measure BBB after SAH primarily focused on exploring innovative methods to predict clinical outcome, delayed cerebral ischemia, and delayed infarction related to delayed cerebral ischemia in acute periods. These predictions are based on detecting abnormal changes in BBB permeability. The parameters of BBB permeability are described by changes in computed tomography (CT) perfusion and magnetic resonance imaging (MRI). K_ep seems to be a stable and sensitive indicator in CT perfusion, whereas K^trans is a reliable parameter for dynamic contrast-enhanced MRI. Future prediction models that utilize both the volume of BBB disruption and stable parameters of BBB may be a promising direction to develop practical clinical tools. These tools could provide greater accuracy in predicting clinical outcome and risk of deterioration. Therapeutic interventional exploration targeting BBB disruption is also promising, considering the extended duration of post-SAH BBB disruption.

Initial inflammatory response is an independent predictor of unfavorable outcome in patients with good-grade aneurysmal subarachnoid hemorrhage

INTRODUCTION

Purpose of the present study was to determine if routine biochemical markers of acute phase response are associated with unfavorable outcome in patients with good-grade aneurysmal SAH.

METHODS

231 patients admitted with aneurysmal SAH and WFNS grade I - II were included in the present study. C-reactive protein (CRP) and procalcitonin (PCT) were measured within 24 h of admission. Outcome was assessed according to the modified Rankin Scale (mRS) after 6 months and stratified into favorable (mRS 0-2) vs. unfavorable (mRS 3-6).

RESULTS

The multivariate regression analysis revealed "elevated baseline CRP" (p = .001, OR 3.2, 95% CI 1.6-6.6), "elevated baseline PCT" (p = .004, OR 26.0, 95% CI 2.9-235.5), "male gender" (p = .02, OR 2.3, 95% CI 1.1-4.8), and "age ≥ 65 years" (p = .009, OR 2.7, 95% CI 1.3-5.8) as a model for the prediction of unfavorable outcome in patients with good-grade SAH.

CONCLUSION

An initial inflammatory response could be a possible explanation for poor outcome in good-grade SAH patients. These findings might help to identify a subgroup of good grade SAH patients who are at greater risk for unfavorable outcome early during treatment course/at baseline, and who could benefit most from potential anti-inflammatory therapy.

The Effects of Cerebral Vasospasm on Cerebral Blood Flow and the Effects of Induced Hypertension: A Mathematical Modelling Study

Background

Induced hypertension has been used to promote cerebral blood flow under vasospastic conditions although there is no randomised clinical trial to support its use. We sought to mathematically model the effects of vasospasm on the cerebral blood flow and the effects of induced hypertension.

Methods

The Anatomically Detailed Arterial Network (ADAN) model is employed as the anatomical substrate in which the cerebral blood flow is simulated as part of the simulation of the whole body arterial circulation. The pressure drop across the spastic vessel is modelled by inserting a specific constriction model within the corresponding vessel in the ADAN model. We altered the degree of vasospasm, the length of the vasospastic segment, the location of the vasospasm, the pressure (baseline mean arterial pressure [MAP] 90 mm Hg, hypertension MAP 120 mm Hg, hypotension), and the presence of collateral supply.

Results

Larger decreases in cerebral flow were seen for diffuse spasm and more severe vasospasm. The presence of collateral supply could maintain cerebral blood flow, but only if the vasospasm did not occur distal to the collateral. Induced hypertension caused an increase in blood flow in all scenarios, but did not normalise blood flow even in the presence of moderate vasospasm (30%). Hypertension in the presence of a complete circle of Willis had a marginally greater effect on the blood flow, but did not normalise flow.

Conclusion

Under vasospastic condition, cerebral blood flow varies considerably. Hypertension can raise the blood flow, but it is unable to restore cerebral blood flow to baseline.

The Role of Sartans in the Treatment of Stroke and Subarachnoid Hemorrhage: A Narrative Review of Preclinical and Clinical Studies

Background: Delayed cerebral vasospasm (DCVS) due to aneurysmal subarachnoid hemorrhage (aSAH) and its sequela, delayed cerebral ischemia (DCI), are associated with poor functional outcome. Endothelin-1 (ET-1) is known to play a major role in mediating cerebral vasoconstriction. Angiotensin-II-type-1-receptor antagonists such as Sartans may have a beneficial effect after aSAH by reducing DCVS due to crosstalk with the endothelin system. In this review, we discuss the role of Sartans in the treatment of stroke and their potential impact in aSAH. Methods: We conducted a literature research of the MEDLINE PubMed database in accordance with PRISMA criteria on articles published between 1980 to 2019 reviewing: "Sartans AND ischemic stroke". Of 227 studies, 64 preclinical and 19 clinical trials fulfilled the eligibility criteria. Results: There was a positive effect of Sartans on ischemic stroke in both preclinical and clinical settings (attenuating ischemic brain damage, reducing cerebral inflammation and infarct size, increasing cerebral blood flow). In addition, Sartans reduced DCVS after aSAH in animal models by diminishing the effect of ET-1 mediated vasoconstriction (including cerebral inflammation and cerebral epileptogenic activity reduction, cerebral blood flow autoregulation restoration as well as pressure-dependent cerebral vasoconstriction). Conclusion: Thus, Sartans might play a key role in the treatment of patients with aSAH.

Induced Hypertension in Preventing Cerebral Infarction in Delayed Cerebral Ischemia After Subarachnoid Hemorrhage

Background and Purpose- Delayed cerebral ischemia (DCI) is an important cause of poor outcome after aneurysmal subarachnoid hemorrhage. If clinical signs of DCI occur, induced hypertension is a plausible but unproven therapeutic intervention. There is clinical equipoise if the use of hypertension induction is useful or not with the consequence that this strategy is irregularly used. We explored the effect of blood pressure augmentation in preventing cerebral infarction in patients with clinical signs of DCI. Methods- We performed a retrospective observational study, totaling 1647 patients with aneurysmal subarachnoid hemorrhage admitted at 3 academic hospitals in the Netherlands between 2006 and 2015. To study the primary outcome DCI related cerebral infarcts, we only included patients with no cerebral infarct at the time of onset of clinical signs of DCI. Cox regression was used to test the association between induced hypertension after onset of clinical signs of DCI and the occurrence of DCI related cerebral infarcts. Logistic regression was used to relate hypertension induction with poor outcome after 3 months, defined as a modified Rankin score >3. Results were adjusted for treatment center and baseline characteristics. Results- Clinical signs of DCI occurred in 479 (29%) patients of whom 300 without cerebral infarction on computed tomography scan at that time. Of these 300 patients, 201 (67%) were treated with hypertension induction and 99 were not. Of the patients treated with hypertension induction, 41 (20%) developed a DCI related cerebral infarct compared with 33 (33%) with no induced hypertension: adjusted hazard ratio, 0.59; 95% CI, 0.35 to 0.99. Hypertension induction also prevented poor outcome: adjusted odds ratio, 0.27; 95% CI, 0.14 to 0.55. Conclusions- Hypertension induction seems an effective strategy for preventing DCI related cerebral infarcts if not already present at the time of onset of clinical signs of DCI. This may lead to a reduction in poor clinical outcome.

The Nimodipine-Sparing Effect of Perioperative Dexmedetomidine Infusion During Aneurysmal Subarachnoid Hemorrhage: A Prospective, Randomized, Controlled Trial

Background: Nimodipine can block the influx of calcium into the vascular smooth muscle cell and prevent secondary ischemia in patients with aneurysmal subarachnoid hemorrhage. However, the reduction of blood pressure after long-term intravenous administration of nimodipine has been associated with neurological deterioration. Yet, no effective solutions have been suggested to address this phenomenon. The use of neuroprotective drug combinations may reduce the risk of sudden blood pressure loss. This prospective, randomized, controlled trial was performed to evaluate the nimodipine-sparing effect of perioperative dexmedetomidine infusion during aneurysmal subarachnoid hemorrhage.

Methods: One hundred nine patients who underwent aneurysm embolization were divided into three groups: group C (n = 35, infused with 0.9% sodium chloride at the same rate as other two groups), group D1 (n = 38, dexmedetomidine infusion at 0.5 µg·kg^–1 for 10 min, then adjusted to 0.2 µg·kg^–1·h^–1), and group D2 (n = 36, dexmedetomidine infusion at 0.5 µg·kg^–1 for 10 min, then adjusted to 0.4 µg·kg^–1·h^–1). Patient-controlled analgesia was given for 48 h after surgery. The primary outcome measure was the total consumption of nimodipine during the first 48 h after surgery. The secondary outcome measures were recovery time at post-anesthesia care unit (PACU), postoperative pain intensity scores, dexmedetomidine and sufentanil consumption, hemodynamic, satisfaction of patients and neurosurgeon, neurologic examination (Glasgow Coma Scale, GCS), Bruggemann comfort scale, and adverse effects. Intraoperative hemodynamics were recorded at the following time-points: arrival at the operating room (T1); before intubation (T2); intubation (T3); 5 min (T4), 10 min (T5), and 15 min (T6) after intubation; suturing of femoral artery (T7); end of surgery (T8); extubation (T9); and 5 min (T10), 10 min (T11), and 15 min (T12) after arrival at the PACU. The level of sedation was recorded at 15 min, 30 min, 1 h, and 2 h after extubation. We also recorded the incidence of symptomatic cerebral vasospasm during 7 days after surgery, Glasgow Outcome Score (GOS) at 3 months, and incidence of cerebral infarction 30 days after surgery.

Results: The consumption of nimodipine during the first 48 h after surgery was significantly lower in group D2 (P < 0.05). Compared with group C, HR and MAP were significantly decreased from T2 to T12 in group D1 and D2 (P < 0.05). Patients in group D2 showed a significantly decreased MAP from T5 to T9 compared with group D1 (P < 0.05). The consumption of sevoflurane, remifentanil, dexmedetomidine, and nimodipine were all significantly reduced in groups D1 and D2 during surgery (P < 0.05). Compared with group C, MAP was significantly decreased in groups D1 and D2 during the first 48 h after surgery (P < 0.05). Compared with group C, consumption of sufentanil and dexmedetomidine at 1 h, pain intensity at 1 h, and 8 h after surgery were significantly decreased in groups D1 and D2 (P < 0.05). FAS was significantly higher in group D2 at 8 h, 16 h, and 24 h after surgery. LOS was significantly lower only in group D2 at 0.5 h after surgery (P < 0.05). Compared with group C, BCS was significantly higher group D2 at 4 h and 8 h after surgery (P < 0.05). There were no significant differences among the three groups in consumption of propofol, cisatracurium, fentanyl, and vasoactive drugs during operation, recovery time at PACU, satisfaction of patients and neurosurgeon, and number of applied urapidil and GCS during the first 48 h after surgery. The incidence of symptomatic cerebral vasospasm during 7 days after surgery, GOS of 3 months, and cerebral infarction after 30 days were also comparable among the three groups.

Conclusions: Dexmedetomidine (infusion at 0.5 µg·kg^–1 for 10 min, then adjusted to 0.4 µg·kg^–1·h^–1 during the surgery) significantly reduced the total consumption of nimodipine during the first 48 h after surgery and promoted early rehabilitation of patients although the incidences of symptomatic cerebral vasospasm, GOS, and cerebral infarction were not reduced.

Medical Treatment Failure for Symptomatic Vasospasm After Subarachnoid Hemorrhage Threatens Long-Term Outcome

Background and Purpose- Symptomatic vasospasm is a common cause of morbidity and mortality after subarachnoid hemorrhage. We sought to identify predictors and the long-term impact of treatment failure with hypertensive therapy for symptomatic vasospasm. Methods- We performed a retrospective analysis of 1520 subarachnoid hemorrhage patients prospectively enrolled in the Columbia University SAH Outcomes Project between August 1996 and August 2012. One hundred ninety-eight symptomatic vasospasm patients were treated with vasopressors to raise arterial blood pressure, with and without volume expansion. Treatment response, defined as complete or near-complete resolution of the initial neurological deficit, was adjudicated in weekly meetings of the study team based on serial clinical examination after hypertensive treatment. Outcome was evaluated at 1 year with the modified Rankin Scale. Results- Twenty-one percent of the 198 patients who received hypertensive therapy did not respond to treatment. Treatment failure was associated with an increased risk of death or severe disability at 1 year (modified Rankin Scale score of 4-6; 62% versus 25%; P<0.001). Failure of medical therapy was also associated with an admission troponin I level >0.3 μg/L (64% versus 28%; P=0.001), aneurysm coiling (43% versus 20%; P=0.004), and involvement of >1 symptomatic vascular territory at onset (39% versus 22%; P=0.02). In multivariable analysis, treatment failure was independently associated only with troponin I elevation (adjusted odds ratio, 4.30; 95% CI, 1.69-11.09; P=0.002). Conclusions- Failure to respond to induced hypertension for symptomatic vasospasm threatens 1-year outcome. Subarachnoid hemorrhage patients with symptomatic vasospasm who have elevated initial troponin I levels, indicative of neurogenic cardiac injury, are at twice the risk of medical treatment failure. Expedited endovascular therapy should be considered in these patients.

Acute Blood Pressure Management in Neurocritically Ill Patients

Optimal blood pressure (BP) management is controversial in neurocritically ill patients due to conflicting concerns of worsening ischemia with decreased BP versus cerebral edema and increased intracranial pressure with elevated BP. In addition, high-quality evidence is lacking regarding optimal BP goals in patients with most of these conditions. This review summarizes guideline recommendations and examines the literature for BP management in patients with ischemic stroke, intracerebral hemorrhage, aneurysmal subarachnoid hemorrhage, traumatic brain injury, and spinal cord injury.

How is vasospasm screening using transcranial Doppler associated with delayed cerebral ischemia and outcomes in aneurysmal subarachnoid hemorrhage?

BACKGROUND

Delayed cerebral ischemia (DCI) is an independent predictor of an unfavorable outcome after aneurysmal subarachnoid hemorrhage (aSAH). Many centers, but not all, use transcranial Doppler (TCD) to screen for vasospasm to help predict DCI. We used the United Kingdom and Ireland Subarachnoid Haemorrhage (UKISAH) Registry to see if outcomes were better in centers that used TCD to identify vasospasm compared to those that did not.

METHODS

TCD screening practices were ascertained by national survey in 13 participating centers of the UKISAH. The routine use of TCD was reported by 5 "screening" centers, leaving 7 "non-screening" centers. Using a cross-sectional cohort study design, prospectively collected data from the UKISAH Registry was used to compare DCI diagnosis and favorable outcome (Glasgow Outcome Score 4 or 5) at discharge based on reported screening practice.

RESULTS

A cohort of 2028 aSAH patients treated ≤ 3 days of hemorrhage was analyzed. DCI was diagnosed in 239/1065 (22.4%) and 220/963 (22.8%) of patients in non-screening and screening centers respectively while 847/1065 (79.5%) and 648/963 (67.2%) achieved a favorable outcome. Odds ratios adjusted for age, injury severity, comorbidities, need for cerebrospinal fluid diversion, and re-bleed returned neutral odds of diagnosing DCI of 0.90 (95% CI 0.72-1.12; p value = 0.347) in screening units compared to those of non-screening units but significantly decreased odds of achieving a favorable outcome 0.56 (95% CI 0.42-0.82; p value < 0.001).

CONCLUSIONS

Centers that screened for vasospasm using TCD had poorer in-hospital outcomes and similar rates of DCI diagnosis compared to centers that did not.

Haemodynamic changes and incisional bleeding after scalp infiltration of dexmedetomidine with lidocaine in neurosurgical patients

BACKGROUND

The purpose of this randomised controlled study is to compare the haemodynamic changes and the degree of incisional bleeding after scalp infiltration of lidocaine and dexmedetomidine versus lidocaine and epinephrine for patients with hemi-facial spasm undergoing microvascular decompression.

METHODS

Fifty-two patients were injected with 5 mL of 1% lidocaine with either dexmedetomidine (2 μg/mL) or epinephrine (1:100,000 dilution) to reduce scalp bleeding. Mean blood pressure and heart rate were recorded every minute for 15 minutes after scalp infiltration. The primary outcome was the incidence of predefined hypotension, which was treated with administration of 4 mg ephedrine as often as needed. The number of administrations and total amount of ephedrine administered were also recorded as a measure of the severity of hypotension. The neurosurgeon scored incisional bleeding by numeric rating scale from 0 (worst) to 10 (best).

RESULTS

The incidence of hypotension (68% vs. 34.8%, P = 0.02) and the frequency (P = 0.02) and total dose (P = 0.03) of ephedrine administered were lower in the dexmedetomidine group than in the epinephrine group. In addition, there was no difference in mean blood pressure between the two groups but heart rates were lower in the dexmedetomidine group (P = 0.01). Incisional site bleeding was better with epinephrine (median [interquartile range] of the numeric rating Score: 6 [4] in the dexmedetomidine group and 8 [2] in the epinephrine group; P < 0.001).

CONCLUSION

The dexmedetomidine-lidocaine combination may be recommended as a substitute for epinephrine-lidocaine for scalp infiltration in neurosurgical patients, especially neurologically compromised patients.

Elevated C-reactive protein and white blood cell count at admission predict functional outcome after non-aneurysmal subarachnoid hemorrhage

INTRODUCTION

Patients with non-aneurysmal subarachnoid hemorrhage (SAH) are considered to have an overall benign course of disease compared to patients suffering from aneurysmal SAH. Nevertheless, a small but significant number of such patients might only achieve unfavorable outcome. Therefore, the purpose of the present study was to determine if routine laboratory markers of acute phase response are associated with unfavorable outcome in patients with non-aneurysmal SAH.

METHODS

From 2006 to 2017, 154 patients suffering from non-aneurysmal SAH were admitted to our institution. Patients were stratified according to the distribution of cisternal blood into patients with perimesencephalic SAH (pSAH) versus non-perimesencephalic SAH (npSAH). C-reactive protein (CRP) and white blood cells (WBC) assessments were performed within 24 h of admission as part of routine laboratory workup. Outcome was assessed according to the modified Rankin Scale (mRS) after 6 months and stratified into favorable (mRS 0-2) vs. unfavorable (mRS 3-6).

RESULTS

The multivariate regression analysis revealed "CRP > 5 mg/l" (p = 0.004, OR 143.7), "WBC count > 12.1 G/l" (p = 0.006, OR 47.8), "presence of IVH" (p = 0.02, OR 13.5), "poor-grade SAH" (p = 0.01, OR 45.2) and "presence of CVS" (p = 0.003, OR 149.9) as independently associated with unfavorable outcome in patients with non-aneurysmal SAH.

CONCLUSION

Elevated C-reactive protein and WBC count at admission were associated with unfavorable outcome after non-aneurysmal SAH.

The safety of post-operative elevation of mean arterial blood pressure following brain tumor resection

We demonstrate the safety of artificially elevating the mean arterial blood pressure (MAP) greater than 85 mmHg or 10% above the mean MAP in patients with underlying hypertension during the acute post-operative period in patients undergoing surgery for resection of brain tumors. A retrospective review was undertaken of all patients undergoing surgery by the senior author between 2013 and 2018. Patients who underwent MAP therapy were analyzed for hemorrhagic and cardiac complications. A total of 1162 of 2270 post-operative brain tumor patients underwent MAP therapy after surgery for a minimum of 24 h post-operatively. Of these, 7/1162 (0.6%) patients experienced intra-cavitary hemorrhage within 5 days of surgery. Two of 7 (29%) patients were diagnosed with venous infarction. One of 7 (14%) patients experienced post-operative, intra-cavitary hemorrhage prior to the initiation of MAP therapy. The remaining 4/1162 (0.35%) patients experienced intra-cavitary hemorrhage post-operatively without clear etiology. In assessing cardiac outcomes, 2/1162 patients (0.2%) experienced elevated troponin levels. No patient demonstrated significant cardiac related morbidity or mortality within this cohort. Post-operative MAP therapy with a goal of maintaining MAP greater than 85 mmHg or 10% above the mean MAP in patients with underlying hypertension appears to be a safe intervention in brain tumor patients for at least 24 h in the post-operative period.

Postinterventional critical care management of aneurysmal subarachnoid hemorrhage

PURPOSE OF REVIEW

Subarachnoid hemorrhage from a ruptured aneurysm (aSAH) is a complex disorder with the potential to have devastating effects on the brain as well as other organ systems. After more than 3 decades of research, the underlying pathophysiologic mechanisms remain incompletely understood and important questions remain regarding the evaluation and management of these patients. The purpose of this review is to analyze the recent literature and improve our understanding of certain key clinical aspects.

RECENT FINDINGS

Growing body of evidence highlights the usefulness of CT perfusion scans in the diagnosis of vasospasm and delayed cerebral ischemia (DCI). Hypervolemia leads to worse cardiopulmonary outcomes and does not improve DCI. The traditional triple H therapy is falling out of favor with hemodynamic augmentation alone now considered the mainstay of medical management. Randomized controlled trials have shown that simvastatin and intravenous magnesium do not prevent DCI or improve functional outcomes after aneurysmal subarachnoid hemorrhage (aSAH). Emerging data using multimodality monitoring has further advanced our understanding of the pathophysiology of DCI in poor grade aSAH.

SUMMARY

The brief review will focus on the postinterventional care of aSAH patients outlining the recent advances over the past few years.

Risk factors for shunt dependency in patients suffering from spontaneous, non-aneurysmal subarachnoid hemorrhage

Patients presenting with spontaneous, non-aneurysmal subarachnoid hemorrhage (SAH) achieve better outcomes compared to patients with aneurysmal SAH. Nevertheless, some patients develop shunt-dependent hydrocephalus during treatment course. We therefore analyzed our neurovascular database to identify factors determining shunt dependency after non-aneurysmal SAH. From 2006 to 2016, 131 patients suffering from spontaneous, non-aneurysmal SAH were admitted to our department. Patients were stratified according to the distribution of cisternal blood into patients with perimesencephalic SAH (pSAH) versus non-perimesencephalic SAH (npSAH). Outcome was assessed according to the modified Rankin Scale (mRS) at 6 months and stratified into favorable (mRS 0-2) versus unfavorable (mRS 3-6). A multivariate analysis was performed to identify predictors of shunt dependency in patients suffering from non-aneurysmal SAH. Overall, 18 of 131 patients suffering from non-aneurysmal SAH developed shunt dependency (14%). In detail, patients with npSAH developed significantly more often shunt dependency during treatment course, when compared to patients with pSAH (p = 0.02). Furthermore, patients with acute hydrocephalus, presence of intraventricular hemorrhage, presence of clinical vasospasm, and anticoagulation medication prior SAH developed significantly more often shunt dependency, when compared to patients without (p < 0.0001). However, "acute hydrocephalus" was the only significant and independent predictor for shunt dependency in all patients with non-aneurysmal SAH in the multivariate analysis (p < 0.0001). The present study identified acute hydrocephalus with the necessity of CSF diversion as significant and independent risk factor for the development of shunt dependency during treatment course in patients suffering from non-aneurysmal SAH.

Induced Hypertension for Delayed Cerebral Ischemia After Aneurysmal Subarachnoid Hemorrhage: A Randomized Clinical Trial

BACKGROUND AND PURPOSE

Induced hypertension is widely used to treat delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage, but a literature review shows that its presumed effectiveness is based on uncontrolled case-series only. We here report clinical outcome of aneurysmal subarachnoid hemorrhage patients with DCI included in a randomized trial on the effectiveness of induced hypertension.

METHODS

Aneurysmal subarachnoid hemorrhage patients with clinical symptoms of DCI were randomized to induced hypertension or no induced hypertension. Risk ratios for poor outcome (modified Rankin Scale score >3) at 3 months, with 95% confidence intervals, were calculated and adjusted for age, clinical condition at admission and at time of DCI, and amount of blood on initial computed tomographic scan with Poisson regression analysis.

RESULTS

The trial aiming to include 240 patients was ended, based on lack of effect on cerebral perfusion and slow recruitment, when 21 patients had been randomized to induced hypertension, and 20 patients to no hypertension. With induced hypertension, the adjusted risk ratio for poor outcome was 1.0 (95% confidence interval, 0.6-1.8) and the risk ratio for serious adverse events 2.1 (95% confidence interval, 0.9-5.0).

CONCLUSIONS

Before this trial, the effectiveness of induced hypertension for DCI in aneurysmal subarachnoid hemorrhage patients was unknown because current literature consists only of uncontrolled case series. The results from our premature halted trial do not add any evidence to support induced hypertension and show that this treatment can lead to serious adverse events.

CLINICAL TRIAL REGISTRATION

URL: http://www.clinicaltrials.gov. Unique identifier: NCT01613235.

Safe Brain Tumor Resection Does not Depend on Surgery Alone - Role of Hemodynamics

Aim of this study was to determine if perioperative hemodynamics have an impact on perioperative infarct volume and patients’ prognosis. 201 cases with surgery for a newly diagnosed or recurrent glioblastoma were retrospectively analyzed. Clinical data and perioperative hemodynamic parameters, blood tests and time of surgery were recorded. Postoperative infarct volume was quantitatively assessed by semiautomatic segmentation. Mean diastolic blood pressure (dBP) during surgery (rho −0.239, 95% CI −0.11 – −0.367, p = 0.017), liquid balance (rho 0.236, 95% CI 0.1–0.373, p = 0.017) and mean arterial pressure (MAP) during surgery (rho −0.206, 95% CI −0.07 – −0.34, p = 0.041) showed significant correlation to infarct volume. A rank regression model including also age and recurrent surgery as possible confounders revealed mean intraoperative dBP, liquid balance and length of surgery as independent factors for infarct volume. Univariate survival analysis showed mean intraoperative dBP and MAP as significant prognostic factors, length of surgery also remained as significant prognostic factor in a multivariate model. Perioperative close anesthesiologic monitoring of blood pressure and liquid balance is of high significance during brain tumor surgery and should be performed to prevent or minimize perioperative infarctions and to prolong survival.

Outcome after Hunt and Hess Grade V subarachnoid hemorrhage: a comparison of pre-coiling era (1980-1995) versus post-ISAT era (2005-2014)

OBJECTIVE Outcome analysis of comatose patients (Hunt and Hess Grade V) after subarachnoid hemorrhage (SAH) is still lacking. The aims of this study were to analyze the outcome of Hunt and Hess Grade V SAH and to compare outcomes in the current period with those of the pre-International Subarachnoid Aneurysm Trial (ISAT) era as well as with published data from trials of decompressive craniectomy (DC) for middle cerebral artery (MCA) infarction. METHODS The authors analyzed cases of Hunt and Hess Grade V SAH from 1980-1995 (referred to in this study as the earlier period) and 2005-2014 (current period) and compared the results for the 2 periods. The outcomes of 257 cases were analyzed and stratified on the basis of modified Rankin Scale (mRS) scores obtained 6 months after SAH. Outcomes were dichotomized as favorable (mRS score of 0-2) or unfavorable (mRS score of 3-6). Data and number needed to treat (NNT) were also compared with the results of decompressive craniectomy (DC) trials for middle cerebral artery (MCA) infarctions. RESULTS Early aneurysm treatment within 72 hours occurred significantly more often in the current period (in 67% of cases vs 22% in earlier period). In the earlier period, patients had a significantly higher 30-day mortality rate (83% vs 39% in the current period) and 6-month mortality rate (94% vs 49%), and no patient (0%) had a favorable outcome, compared with 23% overall in the current period (p < 0.01, OR 32), or 29.5% of patients whose aneurysms were treated (p < 0.01, OR 219). Cerebral infarctions occurred in up to 65% of the treated patients in the current period. Comparison with data from DC MCA trials showed that the NNTs were significantly lower in the current period with 2 for survival and 3 for mRS score of 0-3 (vs 3 and 7, respectively, for the DC MCA trials). CONCLUSIONS Early and aggressive treatment resulted in a significant improvement in survival rate (NNT = 2) and favorable outcome (NNT = 3 for mRS score of 0-3) for comatose patients with Hunt and Hess Grade V SAH compared with the earlier period. Independent predictors for favorable outcome were younger age and bilateral intact corneal reflexes. Despite a high rate of cerebral infarction (65%) in the current period, 29.5% of the patients who received treatment for their aneurysms during the current era (2005-2014) had a favorable outcome. However, careful individual decision making is essential in these cases.

Effect of heparin on secondary brain injury in patients with subarachnoid hemorrhage: an additional ‘H’ therapy in vasospasm treatment

Objective

Secondary brain injury leads to high morbidity and mortality rates in patients with aneurysmal subarachnoid hemorrhage (aSAH). However, evidence-based treatment strategies are sparse. Since heparin has various effects on neuroinflammation, microthromboembolism and vasomotor function, our objective was to determine whether heparin can be used as a multitarget prophylactic agent to ameliorate morbidity in SAH.

Methods

Between June 1999 and December 2014, 718 patients received endovascular treatment after rupture of an intracranial aneurysm at our institution; 197 of them were treated with continuous unfractionated heparin in therapeutic dosages after the endovascular procedure. We performed a matched pair analysis to evaluate the effect of heparin on cerebral vasospasm (CVS), cerebral infarction (CI), and outcome.

Results

The rate of severe CVS was significantly reduced in the heparin group compared with the control group (14.2% vs 25.4%; p=0.005). CI and multiple ischemic lesions were less often present in patients with heparin treatment. These effects were enhanced if patients were treated with heparin for >48 hours, but the difference was not significant. Favorable outcome at 6-month follow-up was achieved in 69% in the heparin group and in 65% in the control group.

Conclusions

Patients receiving unfractionated continuous heparin after endovascular aneurysm occlusion have a significant reduction in the rate of severe CVS, have CI less often, and tend to have a favorable outcome more often. Our findings support the potential beneficial effects of heparin as a multitarget therapy in patients with SAH, resulting in an additional ‘H’ therapy in vasospasm treatment.

The use of a stent-retriever to cause mechanical dilatation of a vasospasm secondary to iatrogenic subarachnoid haemorrhage

Objective To report the use of a stent-retriever in the management of vasospasm secondary to craniopharyngioma resection. Postoperative improvement was seen both clinically and on perfusion imaging. Methods A patient was admitted for resection of a large craniopharygioma. On day 6 postoperatively the patient had an acute hemiparesis. A computed tomography angiogram and perfusion scan demonstrated acute right-sided cerebral vasospasm and a perfusion defect in the territory of the middle cerebral artery (MCA). Results A pREset 4 × 20 mm stent-retriever was used to dilate the M1 and proximal M2 segments of the right MCA mechanically. This resulted in immediate dilatation of the spastic segment and improvement in the transit time on the angiogram. There was an improvement in the clinical status post-procedure and a computed tomography perfusion performed 24 hours after the procedure showed symmetrical perfusion. A computed tomography angiogram and magnetic resonance imaging performed 1 week later showed a symmetrical appearance to the MCA and no evidence of restricted diffusion. Conclusion The use of commercially available stent-retrievers can cause mechanical dilatation of vasospastic vessels. The stents do not need to be deployed for a prolonged period nor do they need to be implanted to have a prolonged dilatory effect on the spastic vessels.

Continuous intra-arterial nimodipine infusion in refractory symptomatic vasospasm after subarachnoid hemorrhage

Introduction

Vasospasm still is a major cause of morbidity after aneurysmal subarachnoid hemorrhage. The purpose of this report is to describe the successful management of severe refractory vasospasm with continuous intra-arterial nimodipine (IAN) treatment.

Case description

A 72-year old right handed woman was admitted with non-traumatic SAH WFNS grade 1. Cerebral computed tomography demonstrated thick blood filling of the basal cisterns, and intraventricular hemorrhage. Cerebral angiogram failed to detect a vascular abnormality. After an uneventful initial course the patient developed symptomatic left middle cerebral artery vasospasm with aphasia and corresponding restriction in diffusion weighted images in the left frontal lobe. Bolus IAN only transiently improved cerebral circulation and clinical signs and symptoms. Continuous-IAN was started and led to full clinical recovery and normalisation of MRI diffusion restrictions.

Discussion and conclusions

Continuous selective intra-arterial infusion of nimodipine may be an option in selected patients with symptomatic vasospasm refractory to conventional treatment after careful consideration of benefits and procedure-related risks.

Management of delayed cerebral ischemia after subarachnoid hemorrhage

For patients who survive the initial bleeding event of a ruptured brain aneurysm, delayed cerebral ischemia (DCI) is one of the most important causes of mortality and poor neurological outcome. New insights in the last decade have led to an important paradigm shift in the understanding of DCI pathogenesis. Large-vessel cerebral vasospasm has been challenged as the sole causal mechanism; new hypotheses now focus on the early brain injury, microcirculatory dysfunction, impaired autoregulation, and spreading depolarization. Prevention of DCI primarily relies on nimodipine administration and optimization of blood volume and cardiac performance. Neurological monitoring is essential for early DCI detection and intervention. Serial clinical examination combined with intermittent transcranial Doppler ultrasonography and CT angiography (with or without perfusion) is the most commonly used monitoring paradigm, and usually suffices in good grade patients. By contrast, poor grade patients (WFNS grades 4 and 5) require more advanced monitoring because stupor and coma reduce sensitivity to the effects of ischemia. Greater reliance on CT perfusion imaging, continuous electroencephalography, and invasive brain multimodality monitoring are potential strategies to improve situational awareness as it relates to detecting DCI. Pharmacologically-induced hypertension combined with volume is the established first-line therapy for DCI; a good clinical response with reversal of the presenting deficit occurs in 70 % of patients. Medically refractory DCI, defined as failure to respond adequately to these measures, should trigger step-wise escalation of rescue therapy. Level 1 rescue therapy consists of cardiac output optimization, hemoglobin optimization, and endovascular intervention, including angioplasty and intra-arterial vasodilator infusion. In highly refractory cases, level 2 rescue therapies are also considered, none of which have been validated. This review provides an overview of current state-of-the-art care for DCI management.

Treatment of cerebral vasospasm with self-expandable retrievable stents: proof of concept

Objective

To report our preliminary experience with the use of stent retrievers to cause vasodilation in patients with delayed cerebral vasospasm secondary to subarachnoid hemorrhage.

Methods

Four patients from two different high volume neurointerventional centers developed cerebral vasospasm following subarachnoid hemorrhage. In addition to standard techniques for the treatment of cerebral vasospasm, we used commercially available stent retrievers (Solitaire and Capture stent retrievers) to treat the vasospastic segment including M2, M1, A2, and A1. We evaluated the safety of this technique, degree of vasodilation, and longevity of the effect.

Results

Stent retrievers can be used to safely achieve cerebral vasodilation in the setting of delayed cerebral vasospasm. The effect is long-lasting (>24 hours) and, in our initial experience, carries a low morbidity. We have not experienced any complications using this technique although we have noted that the radial force was not sufficient to cause vasodilation in some instances. The vasospasm did not return in the vessel segments treated with stent angioplasty in any of these cases. In two of our cases stent angioplasty resulted in the reversal of focal neurological symptoms.

Conclusions

Stent retrievers can provide long-lasting cerebral vasodilation in patients with delayed cerebral vasospasm.

Delayed cerebral ischaemia prevention and treatment after aneurysmal subarachnoid haemorrhage: a systematic review

: The leading cause of morbidity and mortality after surviving the rupture of an intracranial aneurysm is delayed cerebral ischaemia (DCI). We present an update of recent literature on the current status of prevention and treatment strategies for DCI after aneurysmal subarachnoid haemorrhage. A systematic literature search of three databases (PubMed, ISI Web of Science, and Embase) was performed. Human clinical trials assessing treatment strategies, published in the last 5 yr, were included based on full-text analysis. Study data were extracted using tables depicting study type, sample size, and outcome variables. We identified 49 studies meeting our inclusion criteria. Clazosentan, magnesium, and simvastatin have been tested in large high-quality trials but failed to show a beneficial effect. Cilostazol, eicosapentaenoic acid, erythropoietin, heparin, and methylprednisolone yield promising results in smaller, non-randomized or retrospective studies and warrant further investigation. Topical application of nicardipine via implants after clipping has been shown to reduce clinical and angiographic vasospasm. Methods to improve subarachnoid blood clearance have been established, but their effect on outcome remains unclear. Haemodynamic management of DCI is evolving towards euvolaemic hypertension. Endovascular rescue therapies, such as percutaneous transluminal balloon angioplasty and intra-arterial spasmolysis, are able to resolve angiographic vasospasm, but their effect on outcome needs to be proved. Many novel therapies for preventing and treating DCI after aneurysmal subarachnoid haemorrhage have been assessed, with variable results. Limitations of the study designs often preclude definite statements. Current evidence does not support prophylactic use of clazosentan, magnesium, or simvastatin. Many strategies remain to be tested in larger randomized controlled trials.

CLINICAL TRIAL REGISTRATION

This systematic review was registered in the international prospective register of systematic reviews.

PROSPERO

CRD42015019817.