; Participants in the International Multi-Disciplinary Consensus Conference on the Critical Care Management of Subarachnoid Hemorrhage. Vasospasm versus delayed cerebral ischemia as an outcome event in clinical trials and observational studies

Troponin I as a Predictor of Transcranial Doppler Sonography Defined Vasospasm in Intensive Care Unit Patients After Spontaneous Subarachnoid Hemorrhage

OBJECTIVE

Elevation of Troponin I (TnI) in spontaneous subarachnoid hemorrhage (SAH) patients is a well-known phenomenon and associated with cardiopulmonary complications and poor outcome. The present study was conducted to investigate the association of the TnI value on admission, and the occurrence of cerebral vasospam in SAH patients.

PATIENTS AND METHODS

A total of 142 patients with SAH, who were admitted to the neurosurgical intensive care unit (ICU) between December 2014 and January 2021 were evaluated. Blood samples were drawn on admission to determine TnI value. Each patient's demographic, radiological and medical data on admission, the modified Ranking Scale score at discharge as well as continuous measurements of transcranial Doppler sonography were analyzed. A maximum mean flow velocity (MMFV) > 120 cm/sec was defined as any vasospasm. These were stratified into severe vasospasms, which were defined as at least two measurements of MMFVs > 200 cm/sec or an increase of MMFV > 50 cm/sec/24 h over two consecutive days or a new neurological deterioration and mild vasospasm defined as MMFVs > 120 cm/sec in absence of severe vasospasm criteria. The total study population was dichotomized into patients with an initially elevated TnI (>0.05 µg/L) and without elevated TnI (≤0.05 μg/L).

RESULTS

A total of 52 patients (36.6%) had an elevated TnI level upon admission, which was significantly associated with lower GCS score (p < 0.001), higher WFNS score (p < 0.001) and higher Fisher grade (p = 0.01) on admission. In this context a higher rate of ischemic brain lesions (p = 0.02), a higher modified Rankin Scale score (p > 0.001) and increased mortality (p = 0.02) at discharge were observed in this group. In addition, TnI was identified as an independent predictor for the occurrence of any vasospasm and severe vasospasm.

CONCLUSION

An initially elevated TnI level is an independent predictor for the occurrence of any and severe vasospasm in patients with SAH.

Comparison of LVIS and Enterprise stent-assisted coiling embolization for ruptured intracranial aneurysms: a propensity score-matched cohort study

The role of a low-profile visualized intraluminal support stent (LVIS) and Enterprise in the treatment of unruptured intracranial aneurysms is well established. Although previous studies have investigated one single type of stent for the treatment of ruptured intracranial aneurysms (RIA), the safety and efficacy between the two types of stents has not been fully explored. Herein we conducted a study to compare the outcomes of the two stents for treatment of RIA. This is a prospective registry database of aneurysmal subarachnoid hemorrhage (aSAH) patients admitted to a single institution between 2018 and 2021. We collected patient baseline information, secondary complications, follow-up angiographic data, long-term prognostic outcomes, and conducted propensity score matching (PSM) analysis with 1:1 ratio and a multivariable logistic regression to compare the outcomes of the two types of stents. A total of 231 patients with RIAs were included in this study, with 108 treated using the LVIS device and 123 treated using the Enterprise device. Before PSM analysis, only the incidence of poor prognosis after 12 months was higher in the Enterprise group comparing to the LVIS group (20% vs. 10%, P = 0.049). After PSM analysis, there was a higher occurrence of delayed cerebral ischemia (DCI) in the Enterprise group compared to the LVIS group (odds ratio [OR] 3.95, 95% confidence interval [CI] [1.20-13.01], P = 0.024). However, no significant difference in prognosis was observed after PSM adjustment. Furthermore, subgroup analysis revealed that patients with female (P = 0.019), hypertension (P = 0.048), and anterior circulation aneurysms (P = 0.019) receiving the Enterprise device had a higher risk of DCI. The overall efficacy of LVIS and Enterprise in the treatment of RIA is comparable, while the incidence of DCI in the LVIS group is lower than that in the Enterprise group after PSM analysis. Registration number: NCT05738083 ( https://clinicaltrials.gov/ ).

Predicting postacute phase anaemia after aneurysmal subarachnoid haemorrhage: nomogram development and validation

BACKGROUND

Anaemia is a severe and common complication in patients with aneurysmal subarachnoid haemorrhage (aSAH). Early intervention for at-risk patients before anaemia occurs is indicated as potentially beneficial, but no validated method synthesises patients' complicated clinical features into an instrument. The purpose of the current study was to develop and externally validate a nomogram that predicted postacute phase anaemia after aSAH.

METHODS

We developed a novel nomogram for aSAH patients to predict postacute phase anaemia (3 days after occurrence of aSAH, prior to discharge) on the basis of demographic information, imaging, type of treatment, aneurysm features, blood tests and clinical characteristics. We designed the model from a development cohort and tested the nomogram in external and prospective validation cohorts. We included 456 aSAH patients from The First Affiliated Hospital for the development, 220 from Sanmen People's Hospital for external validation and a prospective validation cohort that included 13 patients from Hangzhou Red Cross Hospital. We assessed the performance of the nomogram via concordance statistics and evaluated the calibration of predicted anaemia outcome with observed anaemia occurrence.

RESULTS

Variables included in the nomogram were age, treatment method (open surgery or endovascular therapy), baseline haemoglobin level, fasting blood glucose level, systemic inflammatory response syndrome score on admission, Glasgow Coma Scale score, aneurysm size, prothrombin time and heart rate. In the validation cohort, the model for prediction of postacute phase anaemia had a c-statistic of 0.910, with satisfactory calibration (judged by eye) for the predicted and reported anaemia outcome. Among forward-looking forecasts, our predictive model achieved an 84% success rate, which showed that it has some clinical practicability.

CONCLUSIONS

The developed and validated nomogram can be used to calculate individualised anaemia risk and has the potential to serve as a practical tool for clinicians in devising improved treatment strategies for aSAH.

Agreement between CT-Angiography and Digital Subtraction Angiography in Predicting Angiographic Vasospasm in Patients with Subarachnoid Hemorrhage

Background/Objectives: Digital subtraction angiography (DSA) is the gold standard in the diagnosis of cerebral vasospasm, frequently observed after subarachnoid hemorrhage (SAH). However, less-invasive methods, such as computed tomography angiography (CTA), may be equally accurate. To further clarify comparability, this study evaluated the reliability of CTA in detecting cerebral vasospasm. Methods: This retrospective study included 51 patients with SAH who underwent both CTA and DSA within 24 h. The smallest diameter of the proximal cerebral arterial segments was measured in both modalities at admission and during the vasospasm period. The mean difference in diameter, the intraclass correlation coefficient (ICC) of CTA and DSA, the difference in grade of vasospasm and sensitivity, the specificity and the positive predictive value (PPV) for CTA were calculated. Results: A total of 872 arterial segments were investigated. At time of admission, arterial diameters were significantly smaller on CTA compared to DSA in all segments (-0.26 ± 0.12 mm; p < 0.05). At time of suspected vasospasm (day 9 ± 5), these differences remained significant only for the M1 segment (-0.18 ± 0.37 mm, p = 0.02), the P1 segment (-0.13 ± 0.24 mm, p = 0.04) and the basilar artery (-0.20 ± 0.37 mm, p = 0.0.04). The ICC between CTA and DSA was good (0.5-0.8). The sensitivity of CTA for predicting angiographic vasospasm was 99%, the specificity was 50% and the PPV was 92%. Conclusions: Arterial diameters measured on CTA may underestimate the arterial caliber observed in DSA; however, these absolute differences were minor. Importantly, vessel diameter alone does not fully reflect malperfusion, requiring additional imaging techniques such as CT perfusion.

Evaluating analgesic medications utilized in the treatment of aneurysmal subarachnoid hemorrhage and association with delayed cerebral ischemia

BACKGROUND

Spontaneous aneurysmal subarachnoid hemorrhage (aSAH) recovery may be hampered by delayed cerebral ischemia (DCI). Herein, we sought to identify whether frequently administered medications in the intensive care unit (ICU) are associated with DCI.

METHODS

In this retrospective study, patients admitted to a tertiary care center neuro-ICU between 2012 and 2019 with aSAH who could verbalize pain intensity scores were included. Medication dosages and clinical characteristics were abstracted from the medical record. Both paired and unpaired analyses were utilized to measure individual DCI risk for a given patient in relation to drug dosages.

RESULTS

119 patients were included; average age was 61.7 ± 15.2 (SD) years, 89 (74.7%) were female, and 32 (26.9%) experienced DCI during admission. Patients with DCI had longer length of stay (19.3 ± 7.4 vs 12.7 ± 5.3 days, p < 0.0001). The combination medication of acetaminophen 325 mg/butalbital 50 mg/caffeine 40 mg (A/B/C) was associated with decreased DCI on paired (2.3 ± 2.0 vs 3.1 ± 1.9 tabs, p = 0.034) and unpaired analysis (1.84 ± 2.4 vs 2.6 ± 2.4 tabs, p < 0.001). No associations were found between DCI and opioids, dexamethasone, levetiracetam, or acetaminophen. Max and mean daily headache pain was not associated with DCI occurrence.

CONCLUSION

We identified an association between a commonly administered analgesic and DCI. A/B/C is associated with decreased DCI in this study, while other medications are not associated with DCI risk.

The Role of Early Serum Biomarkers and Clinical Rating Scales in the Prediction of Delayed Cerebral Ischaemia and Short-Term Outcome after Aneurysmal Subarachnoid Haemorrhage: Single Centre Experience

Considering the variety of complications that arise after aneurysmal subarachnoid haemorrhage (aSAH) and the complex pathomechanism of delayed cerebral ischaemia (DCI), the task of predicting the outcome assumes a profound complexity. Therefore, there is a need to develop early predictive and decision-making models. This study explores the effect of serum biomarkers and clinical scales on patients' outcomes and their interrelationship with DCI and systemic complications in aSAH. This was a retrospective analysis including aSAH patients admitted to the Wroclaw University Hospital (Wrocław, Poland) from 2011 to 2020. A good outcome was defined as a modified Rankin Scale (mRS) score of 0-2. The prediction of the development of DCI and poor outcome was conducted using logistic regression as a standard model (SM) and random forest as a machine learning method (ML). A cohort of 174 aSAH patients were included in the analysis. DCI was diagnosed in 79 (45%) patients. Significant differences between patients with poor vs. good outcome were determined from their levels of albumin (31 ± 7 vs. 35 ± 5 (g/L); p < 0.001), D-dimer (3.0 ± 4.5 vs. 1.5 ± 2.8 (ng/mL); p < 0.001), procalcitonin (0.2 ± 0.4 vs. 0.1 ± 0.1 (ng/mL); p < 0.001), and glucose (169 ± 69 vs. 137 ± 48 (nmol/L); p < 0.001). SM for DCI prediction included the Apache II scale (odds ratio [OD] 1.05; 95% confidence interval [CI] 1.00-1.09) and albumin level (OD 0.88; CI 0.82-0.95). ML demonstrated that low albumin level, high Apache II scale, increased D-dimer and procalcitonin levels had the highest predictive values for DCI. The integration of clinical parameters and scales with a panel of biomarkers may effectively facilitate the stratification of aSAH patients, identifying those at high risk of secondary complications and poor outcome.

Cerebral Perfusion Pressure-Guided Therapy in Patients with Subarachnoid Haemorrhage-A Retrospective Analysis

BACKGROUND

Prevention and treatment of haemodynamic instability and increased intracranial pressure (ICP) in patients with subarachnoid haemorrhage (SAH) is vital. This study aimed to evaluate the effects of protocolised cerebral perfusion pressure (CPP)-guided treatment on morbidity and functional outcome in patients admitted to the intensive care unit (ICU) with SAH.

METHODS

We performed a retrospective study comparing 37 patients who received standard haemodynamic treatment (control group) with 17 individuals (CPP-guided group) who were on the CPP-guided treatment aimed at maintaining CPP > 70 mmHg using both optimisations of ICP and mean arterial pressure (MAP).

RESULTS

MAP, cumulative crystalloid doses and fluid balance were similar in both groups. However, the incidence of delayed cerebral ischaemia was significantly lower in the CPP-guided group (14% vs. 64%, p < 0.01), and functional outcome as assessed by the Glasgow Outcome Scale at 30 days after SAH was improved (29.0% vs. 5.5%, p = 0.03).

CONCLUSIONS

This preliminary analysis showed that implementing a CPP-guided treatment approach aimed at maintaining a CPP > 70 mmHg may reduce the occurrence of delayed cerebral ischaemia and improve functional outcomes in patients with SAH. This observation merits further prospective investigation of the use of CPP-guided treatment in patients with SAH.

Distal cerebral vasospasm treatment following aneurysmal subarachnoid hemorrhage using the Comaneci device: technical feasibility and single-center preliminary results

BACKGROUND

Balloon-assisted mechanical angioplasty for cerebral vasospasm following aneurysmal subarachnoid hemorrhage (aSAH) has a number of limitations, including transient occlusion of the spastic blood vessel. Comaneci is an FDA-approved device for temporary coil embolization assistance which has recently also been approved for the treatment of distal symptomatic refractory vasospasm. We aimed to report the feasibility, efficacy and safety of our experience with Comaneci angioplasty for refractory distal vasospasm (up to the second segment of the cerebral arteries) following aSAH.

METHODS

This is a retrospective analysis of a prospective series of 18 patients included between April 2019 and June 2021 with aSAH and symptomatic vasospasm refractory to medical therapy, who were treated using Comaneci-17-asssisted mechanical distal angioplasty. Immediate angiographic results, procedure-related complications, and clinical outcomes were assessed. Inter-rater reliability of the scores was determined using the intraclass correlation coefficient.

RESULTS

Comaneci-assisted distal angioplasty was performed in 18 patients, corresponding to 31 target arteries. All distal anterior segments were easily accessible with the Comaneci-17 device. Vasospasm improvement after Comaneci mechanical angioplasty was seen in 22 distal arteries (71%) (weighted Cohen's kappa (κ_w) 0.73, 95% CI 0.69 to 0.93). Vasospasm recurrence occurred in three patients (16.67%) and delayed cerebral infarction in three patients (16.67%), with a mean±SD delay between onset of symptoms and imaging follow-up (MRI/CT) of 32.61±8.93 days (κ_w 0.98, 95% CI 0.88 to 1).

CONCLUSION

This initial experience suggests that distal mechanical angioplasty performed with the Comaneci-17 device for refractory vasospasm following aSAH seems to be safe, with good feasibility and efficacy.

Microvascular cerebral blood flow response to intrathecal nicardipine is associated with delayed cerebral ischemia

One of the common complications of non-traumatic subarachnoid hemorrhage (SAH) is delayed cerebral ischemia (DCI). Intrathecal (IT) administration of nicardipine, a calcium channel blocker (CCB), upon detection of large-artery cerebral vasospasm holds promise as a treatment that reduces the incidence of DCI. In this observational study, we prospectively employed a non-invasive optical modality called diffuse correlation spectroscopy (DCS) to quantify the acute microvascular cerebral blood flow (CBF) response to IT nicardipine (up to 90 min) in 20 patients with medium-high grade non-traumatic SAH. On average, CBF increased significantly with time post-administration. However, the CBF response was heterogeneous across subjects. A latent class mixture model was able to classify 19 out of 20 patients into two distinct classes of CBF response: patients in Class 1 (n = 6) showed no significant change in CBF, while patients in Class 2 (n = 13) showed a pronounced increase in CBF in response to nicardipine. The incidence of DCI was 5 out of 6 in Class 1 and 1 out of 13 in Class 2 (p &lt; 0.001). These results suggest that the acute (&lt;90 min) DCS-measured CBF response to IT nicardipine is associated with intermediate-term (up to 3 weeks) development of DCI.

Blood pressure and the risk of rebleeding and delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage

INTRODUCTION AND OBJECTIVE

Blood pressure is presumably related to rebleeding and delayed cerebral ischemia (DCI) after subarachnoid hemorrhage (aSAH) and could serve as a target to improve outcome. We assessed the associations between blood pressure and rebleeding or DCI in aSAH-patients.

MATERIALS AND METHODS

In this observational study in 1167 aSAH-patients admitted to the intensive care unit (ICU), adjusted hazard ratio's (aHR) were calculated for the time-dependent association of blood pressure and rebleeding or DCI. The aHRs were presented graphically, relative to a reference mean arterial pressure (MAP) of 100 mmHg and systolic blood pressure (sBP) of 150 mmHg.

RESULTS

A MAP below 100 mmHg in the 6, 3 and 1 h before each moment in time was associated with a decreased risk of rebleeding (e.g. within 6 h preceding rebleeding: MAP = 80 mmHg: aHR 0.30 (95% confidence interval (CI) 0.11-0.80)). A MAP below 60 mmHg in the 24 h before each moment in time was associated with an increased risk of DCI (e.g. MAP = 50 mmHg: aHR 2.59 (95% CI 1.12-5.96)).

CONCLUSIONS

Our results suggest that a MAP below 100 mmHg is associated with decreased risk of rebleeding, and a MAP below 60 mmHg with increased risk of DCI.

Health Care Expenditures Associated with Delayed Cerebral Ischemia Following Subarachnoid Hemorrhage: A Propensity-Adjusted Analysis

OBJECTIVE

The additional hospital costs associated with delayed cerebral ischemia (DCI) have not been well investigated in prior literature. In this study, the total hospital cost of DCI in aneurysmal subarachnoid hemmorhage (aSAH) patients treated at a single quaternary center was analyzed.

METHODS

All patients in the Post-Barrow Ruptured Aneurysm Trial treated for an aSAH between January 1, 2014, and July 31, 2019, were retrospectively analyzed. DCI was defined as cerebral infarction identified on computed tomography, magnetic resonance imaging, or autopsy after exclusion of procedure-related infarctions. The primary outcome was the difference in total cost (including hospital, discharge facility, and all follow-up) using a propensity-adjusted analysis. Propensity score covariate-adjusted linear regression analysis included age, sex, open versus endovascular treatment, Hunt and Hess score, and Charlson Comorbidity Index score.

RESULTS

Of the 391 patients included, 144 (37%) had DCI. Patients with DCI had a significantly greater cost compared to patients without DCI (mean standard deviation $112,081 [$54,022] vs. $86,159 [$38,817]; P < 0.001) and a significantly greater length of stay (21 days [11] vs. 18 days [8], P = 0.003, respectively). In propensity-adjusted linear regression analysis, both DCI (odds ratio, $13,871; 95% confidence interval, $7558-$20,185; P < 0.001) and length of stay (odds ratio, $3815 per day; 95% confidence interval, $3480-$4149 per day; P < 0.001) were found to significantly increase the cost.

CONCLUSIONS

The significantly higher costs associated with DCI further support the evidence that adverse effects associated with DCI in aSAH pose a significant burden to the health care system.

Made to measure—Selecting outcomes in aneurysmal subarachnoid hemorrhage research

There has been limited new high-level evidence generated to guide aneurysmal subarachnoid hemorrhage (aSAH) management in the past decade. The choice of outcome measures used in aSAH clinical trials may be one of the factors hindering progress. In this narrative review we consider the current process for determining “what” to measure in aSAH and identify some of the shortcomings of these approaches. A consideration of the unique clinical course of aSAH is then discussed and how this impacts on selecting the best timepoints to assess change in the chosen constructs. We also review the how to critically appraise different measurement instruments and some of the issues with how these are applied in the context of aSAH. We conclude with current initiatives to improve outcome selection in aSAH and future directions in the research agenda.

Treatment during cerebral vasospasm phase-complication association and outcome in aneurysmal subarachnoid haemorrhage

Background

Aneurysm treatment during cerebral vasospasm (CVS) phase is frequently considered as particularly dangerous, mainly because of the risk of cerebral infarct.

Objective

We aimed to evaluate the risk of aneurysmal subarachnoid haemorrhage (aSAH)-specific complications and functional outcome in patients treated during CVS phase.

Methods

We retrospectively analysed a large, retro- and prospectively collected database of aSAH patients admitted to our department between March 2006 and March 2020. We conducted a uni- and multivariable logistic regression analysis to evaluate influencing factors on rebleeding, cerebral infarct, Glasgow Outcome Score (GOS) at discharge and mortality and assessed the rate of angiographic vasospasm on admission.

Results

We included 853 patients. The majority of patients were female (66.6%), mean age was 57.3 years. Out of 853 included patients, 92 (10.8%) were treated during CVS phase, 312 (36.6%) underwent clipping and 541 (63.4%) endovascular treatment. Treatment during CVS phase was significantly associated with cerebral infarct in the multivariable logistic regression analysis, unrelated to the nature of intervention (OR 2.42, 1.29–4.54 95% CI p-value = 0.006). However, patients treated during CVS phase did not have increased risk of unfavourable outcome by GOS on discharge. In addition, they did not have a higher rate of rebleeding or mortality.

Conclusions

Treatment during CVS phase was significantly associated with a higher rate of cerebral infarct as confirmed by imaging. This did not reflect on GOS on discharge, rebleeding, or mortality. Aneurysm treatment during CVS phase is relatively safe and should not be postponed due to the risk of rebleeding and subsequent devastating deterioration.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00415-022-11212-w.

C-reactive protein elevation predicts in-hospital deterioration after aneurysmal subarachnoid hemorrhage: a retrospective observational study

Background

There is increasing evidence that inflammation plays a role in the pathogenesis of aneurysmal subarachnoid hemorrhage (aSAH) and in the development of delayed cerebral ischemia (DCI). However, the assessment and interpretation of classically defined inflammatory parameters is difficult in aSAH patients. The objective of this study was to investigate the relationship between easily assessable findings (hyperventilation, fever, white blood cell count (WBC), and C-reactive protein (CRP)) and the occurrence of DCI and unfavorable neurological outcome at discharge in aSAH patients.

Methods

Retrospective analysis of prospectively collected data from a single center cohort. We evaluated the potential of clinical signs of inflammation (hyperventilation, fever) and simple inflammatory laboratory parameters CRP and WBC to predict unfavorable outcomes at discharge and DCI in a multivariate analysis. A cutoff value for CRP was calculated by Youden’s J statistic. Outcome was measured using the modified Rankin score at discharge, with an unfavorable outcome defined as modified Rankin scale (mRS) > 3.

Results

We included 97 consecutive aSAH patients (63 females, 34 males, mean age 58 years) in the analysis. Twenty-one (22%) had major disability or died by the time of hospital discharge. Among inflammatory parameters, CRP over 100 mg/dl on day 2 was an independent predictor for worse neurological outcome at discharge. The average C-reactive protein level in the first 14 days was higher in patients with a worse neurological outcome (96.6, SD 48.3 vs 56.3 mg/dl, SD 28.6) in the first 14 days after aSAH. C-reactive protein on day 2 was an indicator of worse neurological outcome. No inflammatory parameter was an independent predictor of DCI. After multivariate adjustment, DCI, increased age, and more than 1 day of mechanical ventilation were significant predictors of worse neurological outcome.

Conclusions

Early elevated CRP levels were a significant predictor of worse neurological outcome at hospital discharge and may be a useful marker of later deterioration in aSAH.

Longitudinal neuropsychological assessment after aneurysmal subarachnoid hemorrhage and its relationship with delayed cerebral ischemia: a prospective Swiss multicenter study

OBJECTIVE

While prior retrospective studies have suggested that delayed cerebral ischemia (DCI) is a predictor of neuropsychological deficits after aneurysmal subarachnoid hemorrhage (aSAH), all studies to date have shown a high risk of bias. This study was designed to determine the impact of DCI on the longitudinal neuropsychological outcome after aSAH, and importantly, it includes a baseline examination after aSAH but before DCI onset to reduce the risk of bias.

METHODS

In a prospective, multicenter study (8 Swiss centers), 112 consecutive alert patients underwent serial neuropsychological assessments (Montreal Cognitive Assessment [MoCA]) before and after the DCI period (first assessment, < 72 hours after aSAH; second, 14 days after aSAH; third, 3 months after aSAH). The authors compared standardized MoCA scores and determined the likelihood for a clinically meaningful decline of ≥ 2 points from baseline in patients with DCI versus those without.

RESULTS

The authors screened 519 patients, enrolled 128, and obtained complete data in 112 (87.5%; mean [± SD] age 53.9 ± 13.9 years; 66.1% female; 73% World Federation of Neurosurgical Societies [WFNS] grade I, 17% WFNS grade II, 10% WFNS grades III-V), of whom 30 (26.8%) developed DCI. MoCA z-scores were worse in the DCI group at baseline (-2.6 vs -1.4, p = 0.013) and 14 days (-3.4 vs -0.9, p < 0.001), and 3 months (-0.8 vs 0.0, p = 0.037) after aSAH. Patients with DCI were more likely to experience a decline of ≥ 2 points in MoCA score at 14 days after aSAH (adjusted OR [aOR] 3.02, 95% CI 1.07-8.54; p = 0.037), but the likelihood was similar to that in patients without DCI at 3 months after aSAH (aOR 1.58, 95% CI 0.28-8.89; p = 0.606).

CONCLUSIONS

Aneurysmal SAH patients experiencing DCI have worse neuropsychological function before and until 3 months after the DCI period. DCI itself is responsible for a temporary and clinically meaningful decline in neuropsychological function, but its effect on the MoCA score could not be measured at the time of the 3-month follow-up in patients with low-grade aSAH with little or no impairment of consciousness. Whether these findings can be extrapolated to patients with high-grade aSAH remains unclear. Clinical trial registration no.: NCT03032471 (ClinicalTrials.gov).

Prophylactic Therapies for Morbidity and Mortality After Aneurysmal Subarachnoid Hemorrhage: A Systematic Review and Network Meta-Analysis of Randomized Trials

BACKGROUND

Aneurysmal subarachnoid hemorrhage (aSAH) is associated with high mortality and morbidity. We aimed to determine the relative benefits of pharmacological prophylactic treatments in patients with aneurysmal subarachnoid hemorrhage by performing a network meta-analysis of randomized trials.

METHODS

We searched Medline, Web of Science, Embase, Scopus, ProQuest, and Cochrane Central to February 2020. Pairs of reviewers independently identified eligible trials, extracted data, and assessed the risk of bias. Eligible trials compared the prophylactic effects of any oral or intravenous medications or intracranial drug-eluting implants to one another or placebo or standard of care in adult hospitalized patients with confirmed aneurysmal subarachnoid hemorrhage. We used the GRADE (Grading of Recommendations Assessment, Development and Evaluation) approach to assess the certainty of the evidence.

RESULTS

We included 53 trials enrolling 10 415 patients. Nimodipine likely reduces all-cause mortality compared to placebo (odds ratio [OR],0.73 [95% CI, 0.53-1.00]; moderate certainty; absolute risk reduction (ARR), -3.35%). Nimodipine (OR, 1.46 [95% CI, 1.07-1.99]; high certainty; absolute risk increase, 8.25%) and cilostazol (OR, 3.73 [95% CI, 1.14-12.18]; moderate certainty; absolute risk increase, 23.15%) were the most effective treatments in improving disability at the longest follow-up. Compared to placebo, clazosentan (10 mg/kg; OR, 0.39 [95% CI, 0.22-0.68]; high certainty; ARR, -16.65%), nicardipine (OR, 0.48 [95% CI, 0.24-0.94]; moderate certainty; ARR, -13.70%), fasudil (OR, 0.55 [95% CI, 0.31-0.98]; moderate certainty; ARR, -11.54%), and magnesium (OR, 0.66 [95% CI, 0.46-0.94]; high certainty; ARR, -8.37%) proved most effective in reducing the likelihood of delayed cerebral ischemia.

CONCLUSIONS

Nimodipine and cilostazol are likely the most effective treatments in preventing morbidity and mortality in patients with aneurysmal subarachnoid hemorrhage. Clazosentan, nicardipine, fasudil, and magnesium showed beneficial effects on delayed cerebral ischemia and vasospasm but they were not found to reduce mortality or disability. Future trials are warranted to elaborately investigate the prophylactic effects of medications that may improve mortality and long-term functional outcomes, such as cilostazol and clazosentan.

REGISTRATION

URL: https://www.crd.york.ac.uk/PROSPERO/; Unique identifier: CRD42019122183.

Combining Transcranial Doppler and EEG Data to Predict Delayed Cerebral Ischemia After Subarachnoid Hemorrhage

BACKGROUND AND OBJECTIVES

Delayed cerebral ischemia (DCI) is the leading complication of subarachnoid hemorrhage (SAH). Because DCI was traditionally thought to be caused by large vessel vasospasm, transcranial Doppler ultrasounds (TCDs) have been the standard of care. Continuous EEG has emerged as a promising complementary monitoring modality and predicts increased DCI risk. Our objective was to determine whether combining EEG and TCD data improves prediction of DCI after SAH. We hypothesize that integrating these diagnostic modalities improves DCI prediction.

METHODS

We retrospectively assessed patients with moderate to severe SAH (2011-2015; Fisher 3-4 or Hunt-Hess 4-5) who had both prospective TCD and EEG acquisition during hospitalization. Middle cerebral artery (MCA) peak systolic velocities (PSVs) and the presence or absence of epileptiform abnormalities (EAs), defined as seizures, epileptiform discharges, and rhythmic/periodic activity, were recorded daily. Logistic regressions were used to identify significant covariates of EAs and TCD to predict DCI. Group-based trajectory modeling (GBTM) was used to account for changes over time by identifying distinct group trajectories of MCA PSV and EAs associated with DCI risk.

RESULTS

We assessed 107 patients; DCI developed in 56 (51.9%). Univariate predictors of DCI are presence of high-MCA velocity (PSV ≥200 cm/s, sensitivity 27%, specificity 89%) and EAs (sensitivity 66%, specificity 62%) on or before day 3. Two univariate GBTM trajectories of EAs predicted DCI (sensitivity 64%, specificity 62.75%). Logistic regression and GBTM models using both TCD and EEG monitoring performed better. The best logistic regression and GBTM models used both TCD and EEG data, Hunt-Hess score at admission, and aneurysm treatment as predictors of DCI (logistic regression: sensitivity 90%, specificity 70%; GBTM: sensitivity 89%, specificity 67%).

DISCUSSION

EEG and TCD biomarkers combined provide the best prediction of DCI. The conjunction of clinical variables with the timing of EAs and high MCA velocities improved model performance. These results suggest that TCD and cEEG are promising complementary monitoring modalities for DCI prediction. Our model has potential to serve as a decision support tool in SAH management.

CLASSIFICATION OF EVIDENCE

This study provides Class II evidence that combined TCD and EEG monitoring can identify delayed cerebral ischemia after SAH.

Multimodality Monitoring for Delayed Cerebral Ischemia in Subarachnoid Hemorrhage: A Mini Review

Aneurysmal subarachnoid hemorrhage is a disease with high mortality and morbidity due in large part to delayed effects of the hemorrhage, including vasospasm, and delayed cerebral ischemia. These two are now recognized as overlapping yet distinct entities, and supportive therapies for delayed cerebral ischemia are predicated on identifying DCI as quickly as possible. The purpose of this overview is to highlight diagnostic tools that are being used in the identification of DCI in the neurocritical care settings.

Predictive Value of the Serum Albumin Level on Admission in Patients With Spontaneous Subarachnoid Hemorrhage

Objective: To determine the effect of the serum albumin level on admission in patients with spontaneous subarachnoid hemorrhage (SAH).

Methods: A total of 229 patients with SAH were divided into control and hypoalbuminemia groups. The serum albumin levels were measured. The data, including age, gender, co-existing medical conditions, risk factors, Hunt-Hess (H-H) grade on admission, Glasgow coma score (GCS) on admission, complications during hospitalizations, length of hospital stay, length of intensive care unit (ICU) stay, in-hospital mortality, survival rate, outcome at discharge, and the 6-month follow-up outcome, were compared between the two groups.

Results: Older age, an increased number of patients who consumed an excess of alcohol, and a lower GCS on admission were findings in the hypoalbuminemia group compared to the control group (p < 0.001). The ratio of patients with H-H grade I on admission in the hypoalbuminemia group was decreased compared to the control group (p < 0.05). Patients with hypoalbuminemia were more likely to be intubated, and have pneumonia and cerebral vasospasm than patients with a normal albumin level on admission (p < 0.001). Furthermore, the length of hospital and ICU stays were longer in the hypoalbuminemia group than the control group (p < 0.001). Hypoalbuminemia on admission significantly increased poor outcomes at discharge (p < 0.001). The number of patients with severe disability was increased and the recovery rate was decreased with respect to in-hospital outcomes in the hypoalbuminemia group than the control group (p < 0.001).

Conclusion: Hypoalbuminemia was shown to be associated with a poor prognosis in patients with SAH.

Detrimental effects of intrahospital transport on cerebral metabolism in patients suffering severe aneurysmal subarachnoid hemorrhage

OBJECTIVE

Intrahospital transport for CT scans is routinely performed for neurosurgical patients. Particularly in the sedated and mechanically ventilated patient, intracranial hypertension and blood pressure fluctuations that might impair cerebral perfusion are frequently observed during these interventions. This study quantifies the impact of intrahospital patient transport on multimodality monitoring measurements, with a particular focus on cerebral metabolism.

METHODS

Forty intrahospital transports in 20 consecutive patients suffering severe aneurysmal subarachnoid hemorrhage (SAH) under continuous intracranial pressure (ICP), brain tissue oxygen tension (pbtO2), and cerebral microdialysis monitoring were prospectively included. Changes in multimodality neuromonitoring data during intrahospital transport to the CT scanner and the subsequent 10 hours were evaluated using linear mixed models. Furthermore, the impact of risk factors at transportation, such as cerebral vasospasm, cerebral hypoxia (pbtO2 < 15 mm Hg), metabolic crisis (lactate-pyruvate ratio [LPR] > 40), and transport duration on cerebral metabolism, was analyzed.

RESULTS

During the transport, the mean ICP significantly increased from 7.1 ± 3.9 mm Hg to 13.5 ± 6.0 mm Hg (p < 0.001). The ICP exceeded 20 mm Hg in 92.5% of patients; pbtO2 showed a parallel rise from 23.1 ± 13.3 mm Hg to 28.5 ± 23.6 mm Hg (p = 0.02) due to an increase in the fraction of inspired oxygen during the transport. Both ICP and pbtO2 returned to baseline values thereafter. Cerebral glycerol significantly increased from 71.0 ± 54.9 µmol/L to 75.3 ± 56.0 µmol/L during the transport (p = 0.01) and remained elevated for the following 9 hours. In contrast, cerebral pyruvate and lactate levels were stable during the transport but showed a significant secondary increase 1-8 hours and 2-9 hours, respectively, thereafter (p < 0.05). However, the LPR remained stable over the entire observation period. Patients with extended transport duration (more than 25 minutes) were found to have significantly higher levels of cerebral pyruvate and lactate as well as lower glutamate concentrations in the posttransport period.

CONCLUSIONS

Intrahospital transport and horizontal positioning during CT scans induce immediate intracranial hypertension and an increase in cerebral glycerol, suggesting neuronal injury. Afterward, sustained impairment of neuronal metabolism for several hours could be observed, which might increase the risk of secondary ischemic events. Therefore, intrahospital transport for neuroradiological imaging should be strongly reconsidered and only indicated if the expected benefit of imaging results outweighs the risks of transportation.

CSF lipocalin-2 increases early in subarachnoid hemorrhage are associated with neuroinflammation and unfavorable outcome

Lipocalin-2 mediates neuro-inflammation and iron homeostasis in vascular injuries of the central nervous system (CNS) and is upregulated in extra-CNS systemic inflammation. We postulate that cerebrospinal fluid (CSF) and blood lipocalin-2 levels are associated with markers of inflammation and functional outcome in subarachnoid hemorrhage (SAH). We prospectively enrolled 67 SAH subjects, serially measured CSF and plasma lipocalin-2, matrix metallopeptidase 9 (MMP-9), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) on post-SAH days 1-5 and assessed outcome by modified Rankin Scale (mRS) every 3 months. Unfavorable outcome is defined as mRS > 2. Twenty non-SAH patients undergoing lumbar drain trial were enrolled as controls. Lipocalin-2 was detectable in the CSF and significantly higher in SAH compared to controls (p < 0.0001). Higher CSF LCN2 throughout post-SAH days 1-5 was associated with unfavorable outcome at 3 (p = 0.0031) and 6 months (p = 0.014). Specifically, higher CSF lipocalin-2 on post-SAH days 3 (p = 0.036) and 5 (p = 0.016) were associated with unfavorable 3-month outcome. CSF lipocalin-2 levels positively correlated with CSF IL-6, TNF-α and MMP-9 levels. Higher plasma lipocalin-2 levels over time were associated with worse 6-month outcome. Additional studies are required to understand the role of lipocalin-2 in SAH and to validate CSF lipocalin-2 as a potential biomarker for SAH outcome.

Delayed Cerebral Ischemia after Subarachnoid Hemorrhage

Delayed cerebral ischemia (DCI) is the most feared complication of aneurysmal subarachnoid hemorrhage (aSAH). It increases the mortality and morbidity associated with aSAH. Previously, large cerebral artery vasospasm was thought to be the sole major contributing factor associated with increased risk of DCI. Recent literature has challenged this concept. We conducted a literature search using PUBMED as the prime source of articles discussing various other factors which may contribute to the development of DCI both in the presence or absence of large cerebral artery vasospasm. These factors include microvascular spasm, micro-thrombosis, cerebrovascular dysregulation, and cortical spreading depolarization. These factors collectively result in inflammation of brain parenchyma, which is thought to precipitate early brain injury and DCI. We conclude that diagnostic modalities need to be refined in order to diagnose DCI more efficiently in its early phase, and newer interventions need to be developed to prevent and treat this condition. These newer interventions are currently being studied in experimental models. However, their effectiveness on patients with aSAH is yet to be determined.

Intracerebral Iron Accumulation may be Associated with Secondary Brain Injury in Patients with Poor Grade Subarachnoid Hemorrhage

BACKGROUND

The amount of intracranial blood is a strong predictor of poor outcome after subarachnoid hemorrhage (SAH). Here, we aimed to measure iron concentrations in the cerebral white matter, using the cerebral microdialysis (CMD) technique, and to associate iron levels with the local metabolic profile, complications, and functional outcome.

METHODS

For the observational cohort study, 36 patients with consecutive poor grade SAH (Hunt & Hess grade of 4 or 5, Glasgow Coma Scale Score ≤ 8) undergoing multimodal neuromonitoring were analyzed for brain metabolic changes, including CMD iron levels quantified by graphite furnace atomic absorption spectrometry. The study time encompassed 14 days after admission. Statistical analysis was performed using generalized estimating equations.

RESULTS

Patients were admitted in a poor clinical grade (n = 26, 72%) or deteriorated within 24 h (n = 10, 28%). The median blood volume in the subarachnoid space was high (SAH sum score = 26, interquartile range 20-28). Initial CMD iron was 44 µg/L (25-65 µg/L), which significantly decreased to a level of 25 µg/L (14-30 µg/L) at day 4 and then constantly increased over the remaining neuromonitoring days (p < 0.01). A higher intraventricular hemorrhage sum score (≥ 5) was associated with higher CMD iron levels (Wald-statistic = 4.1, df  = 1, p = 0.04) but not with the hemorrhage load in the subarachnoid space (p = 0.8). In patients developing vasospasm, the CMD iron load was higher, compared with patients without vasospasm (Wald-statistic = 4.1, degree of freedom = 1, p = 0.04), which was not true for delayed cerebral infarction (p = 0.4). Higher iron concentrations in the brain extracellular fluid (34 µg/L, 36-56 µg/L vs. 23 µg/L, 15-37 µg/L) were associated with mitochondrial dysfunction (CMD lactate to pyruvate ratio > 30 and CMD-pyruvate > 70 µM/L, p < 0.001). Brain extracellular iron load was not associated with functional outcome after 3 months (p > 0.5).

CONCLUSIONS

This study suggests that iron accumulates in the cerebral white matter in patients with poor grade SAH. These findings may support trials aiming to scavenger brain extracellular iron based on the hypothesis that iron-mediated neurotoxicity may contribute to acute and secondary brain injury following SAH.

Subarachnoid Hemorrhage Early Brain Edema Score (SEBES) as a radiographic marker of clinically relevant intracranial hypertension and unfavorable outcome after subarachnoid hemorrhage

BACKGROUND AND PURPOSE

The severity of early brain edema (EBE) after aneurysm rupture was reported to be strongly associated with the risk of poor outcome after aneurysmal subarachnoid hemorrhage (SAH). Using the recently developed Subarachnoid Hemorrhage Early Brain Edema Score (SEBES), we analyzed the predictors of EBE and its impact on complications related to intracranial pressure (ICP) increase after SAH and on poor outcome.

METHODS

All consecutive SAH cases treated between January 2003 and June 2016 with assessable SEBES were included (n = 745). Data on demographic characteristics, medical history, initial severity of SAH, need for conservative ICP treatment and decompressive craniectomy, occurrence of cerebral infarctions and unfavorable outcome at 6 months (modified Rankin scale score > 2) were collected. Univariable and multivariable analyses were performed.

RESULTS

Younger age (<55 years; adjusted odds ratio [aOR] 3.16, 95% confidence interval [CI] 2.28-4.38), female sex (aOR 1.64, 95% CI 1.16-2.31), poor initial clinical condition (World Federation of Neurosurgical Societies score 4-5; aOR 1.74, 95% CI 1.23-2.46), presence of intracerebral hemorrhage (aOR 1.63, 95% CI 1.12-2.36), hypothyroidism (aOR 0.60, 95% CI 0.37-0.98) and renal comorbidity (aOR 0.29, 95% CI 0.11-0.78) were independently associated with SEBES (scores 3-4). There was an independent association between SEBES 3-4 and the need for conservative ICP treatment (aOR 2.43, 95% CI 1.73-3.42), decompressive craniectomy (aOR 2.68, 95% CI 1.84-3.89), development of cerebral infarcts (aOR 2.24, 95% CI 1.53-3.29) and unfavorable outcome (aOR 1.48, 95% CI 1.0-2.17).

CONCLUSIONS

SEBES is a reliable predictor of ICP-related complications and poor outcome of SAH. Our findings highlight the need for further research of the impact of patients' demographic characteristics and comorbidities on the severity of EBE after SAH.

Isofurans and Isoprostanes as Potential Markers of Delayed Cerebral Ischemia Following Aneurysmal Subarachnoid Hemorrhage: A Prospective Observational Study

BACKGROUND

F2-Isoprostanes (F2-IsoPs) and Isofurans (IsoF), specific markers of lipid peroxidation in vivo, have been reported to be elevated and have prognostic implications following subarachnoid hemorrhage (SAH). Platelet activation and vasoconstriction are attributed to these compounds. Elevated IsoF to F2-IsoPs ratios have been proposed as in vivo biomarkers of mitochondrial dysfunction. In this pilot study, we examined their performance as specific biomarkers for delayed cerebral ischemia (DCI) development following SAH.

METHODS

Eighteen patients with SAH and six controls with normal neuroimaging and cerebrospinal fluid (CSF) analysis results underwent CSF sampling and abstraction of clinical, demographic, and laboratory data. Samples (two) of CSF were collected on day 1 and once on days 5-8 post bleed. F2-IsoP and IsoF assays were performed by gas chromatography/mass spectroscopy methods. Levels are expressed in median (interquartile range) for nonnormally distributed data. Repeated sample measurements were compared using the Wilcoxon signed-rank test, whereas the Mann-Whitney U-test was used for other nonnormally distributed data.

RESULTS

Mean age was 61 ± 15.7 (SAH cases) versus 48 ± 10 (controls) years, and 80% of patients with SAH were women. Median Hunt and Hess score was 3 (2-4), and modified Fisher scale was 3 (3-4). Thirty nine percent of patients developed DCI. F2-IsoP were significantly higher in SAH cases than in controls [47.5 (30.2-53.5) vs. 26.0 (21.2-34.5) pg/mL]. No significant differences were observed in patients with or without DCI [41 (33.5-52) vs. 44 (28.5-55.5) pg/mL]. IsoF were elevated in the second CSF sample in nine patients but were undetectable in the remainder cases and all controls. Patients who developed DCI had significantly higher IsoF than those who did not [57 (34-72) vs. 0 (0-34) pg/mL]. Patients who met criteria for DCI had a significantly higher IsoF to F2IsoPs ratio on the late CSF sample [1.03 (1-1.38) vs. 0 (0-0.52)].

CONCLUSIONS

Preliminary findings from this study suggest that IsoF may represent a specific biomarker predicting DCI following SAH. Future studies to further explore the value of IsoF as biomarkers of secondary brain injury following SAH seem warranted.

Does intrathecal nicardipine for cerebral vasospasm following subarachnoid hemorrhage correlate with reduced delayed cerebral ischemia? A retrospective propensity score-based analysis

OBJECTIVE

Cerebral vasospasm and delayed cerebral ischemia (DCI) contribute to poor outcome following subarachnoid hemorrhage (SAH). With the paucity of effective treatments, the authors describe their experience with intrathecal (IT) nicardipine for this indication.

METHODS

Patients admitted to the Emory University Hospital neuroscience ICU between 2012 and 2017 with nontraumatic SAH, either aneurysmal or idiopathic, were included in the analysis. Using a propensity-score model, this patient cohort was compared to patients in the Subarachnoid Hemorrhage International Trialists (SAHIT) repository who did not receive IT nicardipine. The primary outcome was DCI. Secondary outcomes were long-term functional outcome and adverse events.

RESULTS

The analysis included 1351 patients, 422 of whom were diagnosed with cerebral vasospasm and treated with IT nicardipine. When compared with patients with no vasospasm (n = 859), the treated group was significantly younger (mean age 51.1 ± 12.4 years vs 56.7 ± 14.1 years, p < 0.001), had a higher World Federation of Neurosurgical Societies score and modified Fisher grade, and were more likely to undergo clipping of the ruptured aneurysm as compared to endovascular treatment (30.3% vs 11.3%, p < 0.001). Treatment with IT nicardipine decreased the daily mean transcranial Doppler velocities in 77.3% of the treated patients. When compared to patients not receiving IT nicardipine, treatment was not associated with an increased rate of bacterial ventriculitis (3.1% vs 2.7%, p > 0.1), yet higher rates of ventriculoperitoneal shunting were noted (19.9% vs 8.8%, p < 0.01). In a propensity score comparison to the SAHIT database, the odds ratio (OR) to develop DCI with IT nicardipine treatment was 0.61 (95% confidence interval [CI] 0.44-0.84), and the OR to have a favorable functional outcome (modified Rankin Scale score ≤ 2) was 2.17 (95% CI 1.61-2.91).

CONCLUSIONS

IT nicardipine was associated with improved outcome and reduced DCI compared with propensity-matched controls. There was an increased need for permanent CSF diversion but no other safety issues. These data should be considered when selecting medications and treatments to study in future randomized controlled clinical trials for SAH.

Aneurysmal Subarachnoid Hemorrhage: Trends, Outcomes, and Predictions From a 15-Year Perspective of a Single Neurocritical Care Unit

BACKGROUND

Aneurysmal subarachnoid hemorrhage (aSAH) is associated with disproportionally high mortality and long-term neurological sequelae. Management of patients with aSAH has changed markedly over the years, leading to improvements in outcome.

OBJECTIVE

To describe trends in aSAH care and outcome in a high-volume single center 15-yr cohort.

METHODS

All new admissions diagnosed with subarachnoid hemorrhage (SAH) to our tertiary neuro-intensive care unit between 2002 and 2016 were reviewed. Trend analysis was performed to assess temporal changes and a step-wise regression analysis was done to identify factors associated with outcomes.

RESULTS

Out of 3970 admissions of patients with SAH, 2475 patients proved to have a ruptured intracranial aneurysm. Over the years of the study, patient acuity increased by Hunt & Hess (H&H) grade and related complications. Endovascular therapies became more prevalent over the years, and were correlated with better outcome. Functional outcome overall improved, yet the main effect was noted in the low- and intermediate-grade patients. Several parameters were associated with poor functional outcome, including long-term mechanical ventilation (odds ratio 11.99, CI 95% [7.15-20.63]), acute kidney injury (3.55 [1.64-8.24]), pneumonia (2.89 [1.89-4.42]), hydrocephalus (1.80 [1.24-2.63]) diabetes mellitus (1.71 [1.04-2.84]), seizures (1.69 [1.07-2.70], H&H (1.67 [1.45-1.94]), and age (1.06 [1.05-1.07]), while endovascular approach to treat the aneurysm, compared with clip-ligation, had a positive effect (0.35 [0.25-0.48]).

CONCLUSION

This large, single referral center, retrospective analysis reveals important trends in the treatment of aSAH. It also demonstrates that despite improvement in functional outcome over the years, systemic complications remain a significant risk factor for poor prognosis. The historic H&H determination of outcome is less valid with today's improved care.

Validation and Optimization of Barrow Neurological Institute Score in Prediction of Adverse Events and Functional Outcome After Subarachnoid Hemorrhage-Creation of the HATCH (Hemorrhage, Age, Treatment, Clinical State, Hydrocephalus) Score

BACKGROUND

The Barrow Neurological Institute (BNI) score, measuring maximal thickness of aneurysmal subarachnoid hemorrhage (aSAH), has previously shown to predict symptomatic cerebral vasospasms (CVSs), delayed cerebral ischemia (DCI), and functional outcome.

OBJECTIVE

To validate the BNI score for prediction of above-mentioned variables and cerebral infarct and evaluate its improvement by integrating further variables which are available within the first 24 h after hemorrhage.

METHODS

We included patients from a single center. The BNI score for prediction of CVS, DCI, infarct, and functional outcome was validated in our cohort using measurements of calibration and discrimination (area under the curve [AUC]). We improved it by adding additional variables, creating a novel risk score (measure by the dichotomized Glasgow Outcome Scale) and validated it in a small independent cohort.

RESULTS

Of 646 patients, 41.5% developed symptomatic CVS, 22.9% DCI, 23.5% cerebral infarct, and 29% had an unfavorable outcome. The BNI score was associated with all outcome measurements. We improved functional outcome prediction accuracy by including age, BNI score, World Federation of Neurologic Surgeons, rebleeding, clipping, and hydrocephalus (AUC 0.84, 95% CI 0.8-0.87). Based on this model we created a risk score (HATCH-Hemorrhage, Age, Treatment, Clinical State, Hydrocephalus), ranging 0 to 13 points. We validated it in a small independent cohort. The validated score demonstrated very good discriminative ability (AUC 0.84 [95% CI 0.72-0.96]).

CONCLUSION

We developed the HATCH score, which is a moderate predictor of DCI, but excellent predictor of functional outcome at 1 yr after aSAH.

Age dependency and modification of the Subarachnoid Hemorrhage Early Brain Edema Score

OBJECTIVE

The Subarachnoid Hemorrhage Early Brain Edema Score (SEBES) system measures cerebral edema on CT and can be used to predict outcome after subarachnoid hemorrhage (SAH). The authors developed a modified SEBES (SEBES 6c) and assessed whether it could predict outcome after SAH better than the SEBES. Furthermore, they verified the age dependency of these scores.

METHODS

In this retrospective study, all patients with aneurysmal SAH in the period from January 2011 to February 2017 at a single institution were analyzed. The SEBES, which is based on the absence of visible sulci at two defined CT levels (0-4 points), and the SEBES 6c were determined from the initial CT. The SEBES 6c system includes the two levels from the original SEBES and one level located 2 cm below the vertex (0-6 points). The authors investigated whether the various SEBESs are age dependent and if they can predict delayed infarction (DI) and outcome.

RESULTS

Two hundred sixty-one patients met the study inclusion criteria. The SEBES was an independent predictor for DI (OR 1.6 per 1-point increase) and unfavorable outcome (OR 1.36 per 1-point increase), in accordance with findings in the first publication on SEBES. However, here the authors found that the SEBES was age dependent. In the age group younger than 60 years, the patients with high-grade SEBESs (3-4 points) had DIs and unfavorable outcomes significantly more often than the patients with low-grade scores (0-2 points). In the age groups 60-69 years and ≥ 70 years, no significant differences in DI and outcome were identified between high-grade and low-grade scores, although trends toward DI and unfavorable outcomes among the 60-69 age group were noted in patients with high-grade SEBESs.Receiver operating characteristic curve analysis showed that SEBES 6c had a higher prognostic value in predicting outcome than SEBES (p < 0.001). Furthermore, SEBES 6c predicted an unfavorable outcome (OR 1.31 per 1-point increase) and DI (OR 1.36 per 1-point increase) independent of vasospasms. SEBES 6c showed an age dependency similar to that of SEBES.

CONCLUSIONS

SEBES 6c is more suitable for predicting outcome after SAH than SEBES. Furthermore, it predicts outcome and DI independently of vasospasm, so it can be used to differentiate between early brain injury- and vasospasm-dependent infarctions and outcome. However, SEBES and SEBES 6c are both age dependent and can be used for patients aged < 60 years and may have limited suitability for patients aged 60-69 years and no suitability for patients aged ≥ 70 years.

Hydroxyethylstarch revisited for acute brain injury treatment

Infusion of the colloid hydroxyethylstarch has been used for volume substitution to maintain hemodynamics and microcirculation after e.g., severe blood loss. In the last decade it was revealed that hydroxyethylstarch can aggravate acute kidney injury, especially in septic patients. Because of the serious risk for critically ill patients, the administration of hydroxyethylstarch was restricted for clinical use. Animal studies and recently published in vitro experiments showed that hydroxyethylstarch might exert protective effects on the blood-brain barrier. Since the prevention of blood-brain barrier disruption was shown to go along with the reduction of brain damage after several kinds of insults, we revisit the topic hydroxyethylstarch and discuss a possible niche for the application of hydroxyethylstarch in acute brain injury treatment.

Patterns of care for ruptured aneurysms of the middle cerebral artery: analysis of a Swiss national database (Swiss SOS)

OBJECTIVE

The objective of this study was to determine patterns of care and outcomes in ruptured intracranial aneurysms (IAs) of the middle cerebral artery (MCA) in a contemporary national cohort.

METHODS

The authors conducted a retrospective analysis of prospective data from a nationwide multicenter registry of all aneurysmal subarachnoid hemorrhage (aSAH) cases admitted to a tertiary care neurosurgical department in Switzerland in the years 2009-2015 (Swiss Study on Aneurysmal Subarachnoid Hemorrhage [Swiss SOS]). Patterns of care and outcomes at discharge and the 1-year follow-up in MCA aneurysm (MCAA) patients were analyzed and compared with those in a control group of patients with IAs in locations other than the MCA (non-MCAA patients). Independent predictors of a favorable outcome (modified Rankin Scale score ≤ 3) were identified, and their effect size was determined.

RESULTS

Among 1866 consecutive aSAH patients, 413 (22.1%) harbored an MCAA. These MCAA patients presented with higher World Federation of Neurosurgical Societies grades (p = 0.007), showed a higher rate of concomitant intracerebral hemorrhage (ICH; 41.9% vs 16.7%, p < 0.001), and experienced delayed cerebral ischemia (DCI) more frequently (38.9% vs 29.4%, p = 0.001) than non-MCAA patients. After adjustment for confounders, patients with MCAA were as likely as non-MCAA patients to experience DCI (aOR 1.04, 95% CI 0.74-1.45, p = 0.830). Surgical treatment was the dominant treatment modality in MCAA patients and at a significantly higher rate than in non-MCAA patients (81.7% vs 36.7%, p < 0.001). An MCAA location was a strong independent predictor of surgical treatment (aOR 8.49, 95% CI 5.89-12.25, p < 0.001), despite statistical adjustment for variables traditionally associated with surgical treatment, such as (space-occupying) ICH (aOR 1.73, 95% CI 1.23-2.45, p = 0.002). Even though MCAA patients were less likely to die during the acute hospitalization (aOR 0.52, 0.30-0.91, p = 0.022), their rate of a favorable outcome was lower at discharge than that in non-MCAA patients (55.7% vs 63.7%, p = 0.003). At the 1-year follow-up, 68.5% and 69.6% of MCAA and non-MCAA patients, respectively, had a favorable outcome (p = 0.676).

CONCLUSIONS

Microsurgical occlusion remains the predominant treatment choice for about 80% of ruptured MCAAs in a European industrialized country. Although patients with MCAAs presented with worse admission grades and greater rates of concomitant ICH, in-hospital mortality was lower and long-term disability was comparable to those in patients with non-MCAA.

Mechanical ventilation in aneurysmal subarachnoid hemorrhage: systematic review and recommendations

Objective

Mechanical ventilation (MV) has a complex interplay with the pathophysiology of aneurysmal subarachnoid hemorrhage (aSAH). We aim to provide a review of the physiology of MV in patients with aSAH, give recommendations based on a systematic review of the literature, and highlight areas that still need investigation.

Data sources

PubMed was queried for publications with the Medical Subject Headings (MeSH) terms “mechanical ventilation” and “aneurysmal subarachnoid hemorrhage” published between January 1, 1990, and March 1, 2020. Bibliographies of returned articles were reviewed for additional publications of interest.

Study selection

Study inclusion criteria included English language manuscripts with the study population being aSAH patients and the exposure being MV. Eligible studies included randomized controlled trials, observational trials, retrospective trials, case-control studies, case reports, or physiologic studies. Topics and articles excluded included review articles, pediatric populations, non-aneurysmal etiologies of subarachnoid hemorrhage, mycotic and traumatic subarachnoid hemorrhage, and articles regarding tracheostomies.

Data extraction

Articles were reviewed by one team member, and interpretation was verified by a second team member.

Data synthesis

Thirty-one articles met the inclusion criteria for this review.

Conclusions

We make recommendations on oxygenation, hypercapnia, PEEP, APRV, ARDS, and intracranial pressure monitoring.

Bioreactance-Based Noninvasive Fluid Responsiveness and Cardiac Output Monitoring: A Pilot Study in Patients with Aneurysmal Subarachnoid Hemorrhage and Literature Review

Management of volume status, arterial blood pressure, and cardiac output are core elements in approaching the patients with aneurysmal subarachnoid hemorrhage (SAH). For the prevention and treatment of delayed cerebral ischemia (DCI), euvolemia is advocated and caution is made towards the avoidance of hypervolemia. Induced hypertension and cardiac output augmentation are the mainstays of medical management during active DCI, whereas the older triple-H paradigm has fallen out of favor due to lack of demonstrable physiological or clinical benefits and serious concern for adverse effects such as pulmonary edema and multiorgan system dysfunction. Furthermore, insight into clinical hemodynamics of patients with SAH becomes salient when one considers the frequently associated cardiac and pulmonary manifestations of the disease such as SAH-associated cardiomyopathy and neurogenic pulmonary edema. In terms of fluid and volume targets, less attention has been paid to dynamic markers of fluid responsiveness despite the well-established, in the general critical care literature, superiority of these as compared to traditionally used static markers such as central venous pressure (CVP). Based on this literature and sound pathophysiologic reasoning, reliance on static markers (such as CVP) is unjustified when one attempts to assess strategies augmenting stroke volume (SV), arterial blood pressure, and oxygen delivery. There are several options for continuous bedside cardiorespiratory monitoring and optimization of SAH patients. We, here, review a noninvasive monitoring technique based on thoracic bioreactance and focusing on continuous cardiac output and fluid responsiveness markers.

Serum Alkaline Phosphatase Level is Associated with Angiographic Vasospasm, Delayed Cerebral Ischemia-Caused Clinical Deterioration, and Functional Outcome After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Alkaline phosphatase (ALP) has been implicated to be associated with poor outcome in ischemic stroke patients, yet its role in aneurysmal subarachnoid hemorrhage (aSAH) patients is unknown. The current study aimed to investigate the on-admission and short-term variation trend of ALP levels in aSAH patients as well as its associations with vasospasm, delayed cerebral ischemia (DCI), and outcome after aSAH.

METHODS

Between January 2014 and May 2018, all consecutive aSAH patients were prospectively enrolled. Blood samples from patients and 78 healthy individuals were obtained. Baseline information, clinical data, and radiologic data were collected, and serum ALP levels during hospitalization were measured. Patients were followed up for 6 months.

RESULTS

One hundred and ninety-six aSAH patients were included. The serum ALP levels in aSAH patients were significantly higher compared to controls (71 vs. 61 U/L, p = 0.0002), yet did not differ significantly between patients with severe (WFNS 4-5) and mild clinical condition (72 vs. 63 U/L, p = 0.3362). However, ALP was significantly higher in patients with severe radiologic status (modified Fisher 3-4) compared to those with mild radiologic status (77 vs. 61.5 U/L, p = 0.0005). A significant correlation emerged between modified Fisher score and ALP level (r = 0.246, p = 0.001). Multivariable analysis found that higher ALP level was associated with angiographic vasospasm (OR 1.019, 95% CI 1.002-1.036, p = 0.026) and DCI-caused clinical deterioration (OR 1.019, 95% CI 1.001-1.037, p = 0.037), while higher WFNS score, modified Fisher score, and ALP level were independently associated with unfavorable outcome (serum ALP level, OR 1.083, 95% CI 1.041-1.127, p < 0.001). Trend analysis of ALP level based on 103 patients' data revealed a significant decrease in ALP level on post-admission day 7-9 (median; on-admission day vs. post-admission day 7-9, 72 vs. 60 U/L, p = 0.0012; post-admission day 3-5 vs. day 7-9, 70 vs. 60 U/L, p = 0.0052) and subsequent increase in ALP level on post-admission day 12-14 (median, 84 U/L, p < 0.0001). Higher ALP levels were observed in patients with unfavorable outcome on on-admission day, post-admission day 3-5, and 12-14 (median; unfavorable vs. favorable; on-admission day, 86 vs. 67 U/L, p = 0.0122; post-admission day 3-5, 80 vs. 64 U/L, p = 0.0044; post-admission day 7-9, 75 vs. 53.5 U/L, p < 0.0001) but not on post-admission day 12-14.

CONCLUSIONS

Elevated serum ALP level is associated with vasospasm, DCI-caused clinical deterioration, and functional outcome after aSAH. Further studies are required to examine the potential role of serum ALP as an outcome predictor for aSAH patients.

Measuring the Impact of Delayed Cerebral Ischemia on Neuropsychological Outcome After Aneurysmal Subarachnoid Hemorrhage-Protocol of a Swiss Nationwide Observational Study (MoCA-DCI Study)

BACKGROUND

The exact relationship between delayed cerebral ischemia (DCI) following aneurysmal subarachnoid hemorrhage (aSAH) and neuropsychological impairment remains unknown, as previous studies lacked a baseline examination after aneurysm occlusion but before the DCI-period. Neuropsychological evaluation of acutely ill patients is often applied in a busy intensive care unit (ICU), where distraction represents a bias to the obtained results.

OBJECTIVE

To evaluate the relationship between DCI and neuropsychological outcome after aSAH by comparing the Montreal Cognitive Assessment (MoCA) results in aSAH patients with and without DCI at 3 mo with a baseline examination before the DCI-period (part 1). To determine the reliability of the MoCA, when applied in an ICU setting (part 2).

METHODS

Prospective, multicenter, and observational study performed at all Swiss neurovascular centers. For part 1, n = 240 consecutive aSAH patients and for part 2, n = 50 patients with acute brain injury are recruited.

EXPECTED OUTCOMES

Part 1: Effect size of the relationship between DCI and neuropsychological outcome (MoCA). Part 2: Reliability measures for the MoCA.

DISCUSSION

The institutional review boards approved this study on July 4, 2017 under case number BASEC 2017-00103. After completion, the results will be offered to an international scientific journal for peer-reviewed publication. This study determines the exact impact of DCI on the neuropsychological outcome after aSAH, unbiased by confounding factors such as early brain injury or patient-specific characteristics. The study provides unique insights in the neuropsychological state of patients in the early period after aSAH.

Transcranial Doppler Sonography Defined Vasospasm, Ischemic Brain Lesions, and Delayed Ischemic Neurological Deficit in Younger and Elderly Patients after Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Vasospasm, delayed ischemic neurologic deficit (DIND), and ischemic brain lesions after acute subarachnoid hemorrhage (SAH) are associated with increased morbidity and mortality. The purpose of this study was to analyze age cutoffs for vasospasm, DIND, and ischemic brain lesions after SAH.

METHODS

This study included 292 aneurysmal SAH patients from January 2005 to December 2015. Patients' data were extracted from a prospective database with measurements of transcranial Doppler sonography. Any vasospasm was defined as a maximum mean flow velocity (MMFV) >120 cm/sec. Severe vasospasms were defined as at least 2 measurements of MMFVs >200 cm/sec or an increase of MMFV >50 cm/sec/24 hours over 2 consecutive days or a new neurologic deficit. All MMFVs >120 cm/sec in absence of severe vasospasm criteria were defined as mild vasospasm. Age-related cutoff values were calculated using receiver operating curve analysis.

RESULTS

Any vasospasms occurred in 142 patients and thereof mild vasospasm in 86/142 (60.6%) patients and severe vasospasm in 56/142 patients (39.4%). Significantly higher incidences of any vasospasm (P = 0.005), severe vasospasm (P = 0.003), DIND (P = 0.031), and ischemic brain lesions (P = 0.04) were observed in patients aged <50 years. According to receiver operating curve analysis, the optimal age cutoff was 50 years for the presence of overall vasospasms, severe vasospasms, DIND, and ischemic brain lesions and 65 years for mild vasospasms.

CONCLUSIONS

Higher incidences of any vasospasms, severe vasospasms, DIND, and ischemic brain lesions were observed in younger SAH patients.

High Early Fluid Input After Aneurysmal Subarachnoid Hemorrhage: Combined Report of Association With Delayed Cerebral Ischemia and Feasibility of Cardiac Output-Guided Fluid Restriction

BACKGROUND

Guidelines on the management of aneurysmal subarachnoid hemorrhage (aSAH) recommend euvolemia, whereas hypervolemia may cause harm. We investigated whether high early fluid input is associated with delayed cerebral ischemia (DCI), and if fluid input can be safely decreased using transpulmonary thermodilution (TPT).

METHODS

We retrospectively included aSAH patients treated at an academic intensive care unit (2007-2011; cohort 1) or managed with TPT (2011-2013; cohort 2). Local guidelines recommended fluid input of 3 L daily. More fluids were administered when daily fluid balance fell below +500 mL. In cohort 2, fluid input in high-risk patients was guided by cardiac output measured by TPT per a strict protocol. Associations of fluid input and balance with DCI were analyzed with multivariable logistic regression (cohort 1), and changes in hemodynamic indices after institution of TPT assessed with linear mixed models (cohort 2).

RESULTS

Cumulative fluid input 0 to 72 hours after admission was associated with DCI in cohort 1 (n=223; odds ratio [OR] 1.19/L; 95% confidence interval 1.07-1.32), whereas cumulative fluid balance was not. In cohort 2 (23 patients), using TPT fluid input could be decreased from 6.0 ± 1.0 L before to 3.4 ± 0.3 L; P = .012), while preload parameters and consciousness remained stable.

CONCLUSION

High early fluid input was associated with DCI. Invasive hemodynamic monitoring was feasible to reduce fluid input while maintaining preload. These results indicate that fluid loading beyond a normal preload occurs, may increase DCI risk, and can be minimized with TPT.

Endogenous arterial blood pressure increase after aneurysmal subarachnoid hemorrhage

OBJECTIVE

Spontaneous blood pressure rise is a frequently observed phenomenon following aneurysmal subarachnoid hemorrhage (SAH). Facing the risk of aneurysmal rebleeding and the occurrence of delayed cerebral ischemia it is unclear how to react to these endogenous-driven blood pressure changes, as their predictive value for clinical course and functional outcome is still unknown.

PATIENTS AND METHODS

Endogenous blood pressure characteristics within 21 days after SAH were retrospectively analyzed in 93 patients. Any use of vasopressors for active induction of hypertension marked the end of data collection. Mean arterial blood pressure (MAP) was related to the onset of cerebral vasospasm and patient characteristics (Hunt&Hess, age, pre-existing hypertension, antihypertensive therapy, sedation). Predictors for cerebral infarction and functional outcome were calculated using a logistic regression model.

RESULTS

A significant MAP increase was observed in all patients from day 3 to day 7. Patients developing cerebral vasospasm had an overall steeper increase of MAP during this period (11.1 ± 11.4 mmHg vs. 6.5 ± 8.9 mmHg, p = 0.04). MAP rise started already 3 days before detection of vasospasm. Lower MAP values were recorded in patients with poor Hunt&Hess grade, under sedation and thus in patients with poor outcome. MAP had no impact on the development of cerebral infarction. In univariate analysis MAP on day 5 (OR 0.95, 95 %-CI: 0.89-0.99), MAP on day 6 (OR 0.95, 95 %-CI: 0.91-1.00), Hunt&Hess grade (OR 1.72, 95 %-CI: 1.14-2.60), sedation (OR 17.04, 95 %-CI: 2.08-139.51) and stroke (OR 5.82, 95 %-CI: 1.63-20.82) were predictors for poor outcome. In multivariable analysis, only sedation (OR 13.72, 95 %-CI: 1.62-115.94) and ischemic stroke (OR 4.48, 95 %-CI: 1.16-17.31) remained significant.

CONCLUSION

Spontaneous MAP increase occured in all patients following SAH. It was highly influenced by clinical parameters, thereby limiting its prognostic value for functional outcome. However, a steep increase of MAP might be an early clinical marker to identify patients at risk for developing cerebral vasospasm.

The role of TLR4 and HO-1 in neuroinflammation after subarachnoid hemorrhage

This review on the mechanisms of neuroinflammation following subarachnoid hemorrhage will focus mainly on toll-like receptor 4 (TLR4), Heme Oxygenase-1 (HO-1), and the role of microglia and macrophages in this process. Vasospasm has long been the focus of research in SAH; however, clinical trials have shown that amelioration of vasospasm does not lead to an improved clinical outcome. This necessitates the need for novel avenues of research. Our work has demonstrated that microglial TLR4 and microglial HO-1, not only affects cognitive dysfunction, but also circadian dysrhythmia in a mouse model of SAH. To attempt to translate these findings, we have also begun investigating macrophages in the cerebrospinal fluid of SAH patients. The goal of this review is to provide an update on the role of TLR4, HO-1, and other signal transduction pathways in SAH-induced neuroinflammation.

Distal Balloon Angioplasty of Cerebral Vasospasm Decreases the Risk of Delayed Cerebral Infarction

BACKGROUND AND PURPOSE

Conventional angioplasty of cerebral vasospasm combines proximal balloon angioplasty (up to the first segment of cerebral arteries) with chemical angioplasty for distal arteries. Distal balloon angioplasty (up to the second segment of cerebral arteries) has been used in our center instead of chemical angioplasty since January 2015. We aimed to assess the effect of this new approach in patients with aneurysmal SAH.

MATERIALS AND METHODS

The occurrence, date, territory, and cause of any cerebral infarction were retrospectively determined and correlated to angioplasty procedures. Delayed cerebral infarction, new angioplasty in the territory of a previous angioplasty, angioplasty complications, 1-month mortality, and 6- to 12-month modified Rankin Scale ≤ 2 were compared between 2 periods (before-versus-after January 2015, from 2012 to 2017) with adjustment for age, sex, World Federation of Neurosurgical Societies score, and the modified Fisher grade.

RESULTS

Three-hundred-ninety-two patients were analyzed (160 before versus 232 after January 2015). Distal balloon angioplasty was associated with the following: higher rates of angioplasty (43% versus 27%, P < .001) and intravenous milrinone (31% versus 9%, P < .001); lower rates of postangioplasty delayed cerebral infarction (2.2% versus 7.5%, P = .01) and new angioplasty (8% versus 19%, P = .003) independent of the rate of patients treated by angioplasty and milrinone; and the same rates of stroke related to angioplasty (3.6% versus 3.1%, P = .78), delayed cerebral infarction (7.7% versus 12.5%, P = .12), mortality (10% versus 11%, P = .81), and favorable outcome (79% versus 73%, P = .21).

CONCLUSIONS

Our study suggests that distal balloon angioplasty is safe and decreases the risk of delayed cerebral infarction and the recurrence of vasospasm compared with conventional angioplasty. It fails to show a clinical benefit possibly because of confounding changes in adjuvant therapies of vasospasm during the study period.

Transpulmonary thermodilution monitoring-guided hemodynamic management improves cognitive function in patients with aneurysmal subarachnoid hemorrhage: a prospective cohort comparison

BACKGROUND

The effects of goal-directed hemodynamic management using transpulmonary thermodilution (TPT) monitor on the cognitive function of patients with aneurysmal subarachnoid hemorrhage (aSAH) remain unclear. The present study aimed to determine whether hemodynamic management with TPT monitor provides better cognitive function compared with standard hemodynamic management.

METHODS

Patients with aSAH who were admitted to the intensive care unit in 2016 were assigned to cohort 1, and those admitted in 2017 were assigned to cohort 2. In cohort 1, hemodynamic and fluid management was performed in accordance with the traditional pressure-based hemodynamic parameters and clinical examination, whereas in cohort 2, it was performed in accordance with the TPT monitor-measured flow-based parameters. The incidence of delayed cerebral ischemia (DCI) and pulmonary edema (PE) was determined. The functional outcome of patients was assessed using the modified Rankin scale (mRS) score and Montreal cognitive assessment (MoCA) test at 1 year following aSAH.

RESULTS

Cohort 1 included 45 patients and cohort 2 included 39 patients who completed the trial. The incidence of DCI (38% versus 26%) and PE (11% versus 3%) was comparable between the cohorts (p > 0.05). The mRS score was similar between the cohorts (p = 0.11). However, the MoCA score was 20.2 (19.2-21.4) and 23.5 (22.2-24.8) in cohort 1 and cohort 2, respectively (p < 0.001). Accordingly, the occurrence of poor MoCA score (38% versus 18%) was significantly lower in cohort 2 (p = 0.045).

CONCLUSIONS

TPT monitor-based hemodynamic management provides better cognitive outcome than standard hemodynamic management in patients with aSAH.

Bexarotene Exerts Protective Effects Through Modulation of the Cerebral Vascular Smooth Muscle Cell Phenotypic Transformation by Regulating PPARγ/FLAP/LTB4 After Subarachnoid Hemorrhage in Rats

Vascular smooth muscle cells (VSMCs) play an important role after a subarachnoid hemorrhage (SAH). The changes in VSMCs following bexarotene treatment after SAH are unknown. In the present study, neurological impairment, decreased cerebral cortical blood flow and transformation of cerebral VSMCs from a contractile to a synthetic phenotype were observed after SAH. Bexarotene reduced neurological impairment, improved cerebral cortical blood flow, inhibited VSMC phenotypic transformation and suppressed the expression of 5-lipoxygenase-activating protein (FLAP) and leukotriene B4 (LTB₄), which was partly reversed by GW9662, an inhibitor of peroxisome proliferator-activated receptor gamma (PPARγ). Mechanistically, sh-PPARγ-mediated phenotypic transformation of VSMCs was partially suppressed by MK886, an antagonist of FLAP. Therefore, we conclude that bexarotene reduced neurological impairment, improved cerebral cortical blood flow and inhibited the VSMC phenotypic transformation after SAH, which was achieved by activating PPARγ-mediated inhibition of FLAP/LTB₄ in VSMCs.

Prediction of Delayed Cerebral Ischemia with Cerebral Angiography: A Meta-Analysis

OBJECT

Cerebral catheter angiography is the gold standard for diagnosing cerebral artery vasospasm (vasospasm) in aneurysmal subarachnoid hemorrhage (SAH). We have previously published a meta-analysis of prediction of delayed cerebral ischemia (DCI) from transcranial Doppler (TCD) evidence of vasospasm. Analogous data relating to prediction of DCI have not been previously collated for cerebral angiography nor reconciled against TCD.

METHODS

We searched PUBMED, the Cochrane database, and clinicaltrials.gov for studies that used cerebral angiography for diagnosis of vasospasm and evaluated DCI in patients with SAH. We performed a random-effects meta-analysis of prediction of DCI with cerebral angiography, reconciling its accuracy against that of TCD. We also report quality of evidence for the value of cerebral angiography and TCD in SAH based on pooled data from our meta-analyses.

RESULTS

A total of 15 studies (n = 5463) were included in the meta-analysis. Sensitivity (SN), specificity (SP), positive predictive value (PPV), and negative predictive value (NPV) of cerebral angiography for prediction of DCI are 57, 68, 32, and 90%. These metrics for TCD, based on our previous meta-analysis, are 90, 71, 57, and 92%. We report that test accuracy estimates are "moderate" for TCD and "low" for angiography based on pooled data from our meta-analyses.

CONCLUSION

TCD evidence of vasospasm is a better predictor of DCI than angiographic vasospasm. Future comparative effectiveness studies can better define the value of these diagnostic tools in patients with SAH.