Loss of Consciousness at Onset of Aneurysmal Subarachnoid Hemorrhage is Associated with Functional Outcomes in Good-Grade Patients

Power suppression in EEG after the onset of SAH is a significant marker of early brain injury in rat models

We analyzed the correlation between the duration of electroencephalogram (EEG) recovery and histological outcome in rats in the acute stage of subarachnoid hemorrhage (SAH) to find a new predictor of the subsequent outcome. SAH was induced in eight rats by cisternal blood injection, and the duration of cortical depolarization was measured. EEG power spectrums were given by time frequency analysis, and histology was evaluated. The appropriate frequency band and recovery percentage of EEG (defined as EEG recovery time) to predict the neuronal damage were determined from 25 patterns (5 bands × 5 recovery rates) of receiver operating characteristic (ROC) curves. Probit regression curves were depicted to evaluate the relationships between neuronal injury and duration of depolarization and EEG recovery. The optimal values of the EEG band and the EEG recovery time to predict neuronal damage were 10-15 Hz and 40%, respectively (area under the curve [AUC]: 0.97). There was a close relationship between the percentage of damaged neurons and the duration of depolarization or EEG recovery time. These results suggest that EEG recovery time, under the above frequency band and recovery rate, may be a novel marker to predict the outcome after SAH.

Walk-In Hospital Admission of Patients with Subarachnoid Hemorrhage: Clinical Presentation and Outcome

OBJECTIVE

Neurosurgeons occasionally encounter cases of subarachnoid hemorrhage (SAH) in admitted walk-in patients, termed "walk-in SAH." However, their clinical characteristics have not been fully understood. We thus, aimed to investigate several characteristics of patients with walk-in SAH and compare them with those of patients with good grade SAH who arrived at the hospital by ambulance.

METHODS

Between January 2011 and January 2018, consecutive patients with World Federation of Neurosurgical Society (WFNS) grade I and II aneurysmal SAH were enrolled. They were dichotomized into walk-in and ambulance groups, and their demographic and disease-related characteristics were compared. Furthermore, predictors associated with unfavorable outcomes were investigated in patients with walk-in SAH.

RESULTS

Of 171 patients with World Federation of Neurosurgical Society grade I and II SAH, 68 (39.8%) were categorized as walk-in SAH. The mean time for diagnosis in patients with walk-in SAH was significantly longer than that in patients who arrived by ambulance (P < 0.01). Multivariate analysis demonstrated that a lower rate of hypertension, high grades on the Barrow Neurological Institute scale, and Early Brain Edema Score were significantly associated with walk-in SAH (odds ratio [OR] 0.44, 95% confidence interval [CI] 0.21-0.91, P = 0.03; OR 0.32, 95% CI 0.13-0.76, P = 0.007; OR 0.11, 95% CI 0.02-0.51, P < 0.0001, respectively). Additionally, severe angiographic vasospasm was a significant predictor of unfavorable outcomes in walk-in SAH (OR 37.7, 95% CI 1.10-1290.90, P = 0.04).

CONCLUSIONS

Patients with walk-in SAH exhibit radiological characteristics associated with a more favorable outcome among patients with good grade SAH. Therefore, these patients may have a positive prognosis.

The clinical course and outcomes of non-aneurysmal subarachnoid hemorrhages in a single-center retrospective study

BACKGROUND

Non-aneurysmal subarachnoid hemorrhages (SAHs) are thought to have a benign clinical course compared to aneurysmal SAHs. The aim of this study is to report the clinical course and outcomes of non-aneurysmal SAHs in a large single-center study.

METHODS

The patients with non-aneurysmal SAHs were screened from Tampere University Hospital from 2005 to 2020. The clinical data were collected from the patient's medical records and from the imaging studies. The primary interest was the neurological outcome assessed by dichotomized GOS at 2 months. Multivariable logistic regression was used to study the factors associated with unfavorable outcome.

RESULTS

We found 216 non-aneurysmal SAHs in 214 patients (2 patients with > 1 bleed). Ninety-seven percent of patients with a typical perimesencephalic bleeding pattern SAH (PSAH) (75/77) had a favorable outcome, while 86% of patients with non-perimesencephalic SAH (NPSAH) had a favorable outcome (84/98). In a multivariable logistic regression analysis, loss of consciousness (LOC) (aOR 214.67, 95% CI 17.62-2615.89) and Fisher grade 4 bleeding pattern (aOR 23.32, 95% CI 1.40-387.98) were associated with increased risk for unfavorable outcome (GOS 1-3). Vasospasm was seen in 20% of non-aneurysmal SAH patients, hydrocephalus in 17%, and 13% needed ventriculostomy.

CONCLUSIONS

Non-aneurysmal SAH seems to have a good prognosis for majority of patients, especially for patients with a PSAH. Non-aneurysmal SAH patients are however affected by vasospasm and hydrocephalus and have similar risk factors for poor outcome as patients with aneurysmal SAH. This suggests that it is the severity of the bleed rather than the etiology that associates with poor outcome.

Predictive factors for pre-intervention rebleeding in aneurysmal subarachnoid haemorrhage: a systematic review and meta-analysis

Rebleeding before intervention is a devastating complication of aneurysmal subarachnoid haemorrhage (aSAH). It often occurs early and is associated with poor outcomes. We present a systematic review and meta-analysis to identify potential predictors of rebleeding in aSAH. A database search identified studies detailing the occurrence of pre-intervention rebleeding in aSAH, and 809 studies were screened. The association between rebleeding and a variety of demographic, clinical, and radiological factors was examined using random effects meta-analyses. Fifty-six studies totalling 33,268 patients were included. Rebleeding occurred in 3,223/33,268 patients (11.1%, 95%CI 9.4-13), with risk decreasing by approximately 0.2% per year since 1981. Systolic blood pressure (SBP) during admission was higher in patients who rebled compared with those who did not (MD 7.4 mmHg, 95%CI 2.2 - 12.7), with increased risk in cohorts with SBP > 160 mmHg (RR 2.12, 95%CI 1.35-3.34), but not SBP > 140 mmHg. WFNS Grades IV-V (RR 2.05, 95%CI 1.13-3.74) and Hunt-Hess grades III-V (RR 2.12, 95%CI 1.38-3.28) were strongly associated with rebleeding. Fisher grades IV (RR 2.24, 95%CI 1.45-3.49) and III-IV (RR 2.05, 95%CI 1.17-3.6) were also associated with an increased risk. Awareness of potential risk factors for rebleeding is important when assessing patients with aSAH to ensure timely management in high-risk cases. Increased SBP during admission, especially > 160 mmHg, poorer clinical grades, and higher radiological grades are associated with an increased risk. These results may also aid in designing future studies assessing interventions aimed at reducing the risk of rebleeding.

Proceedings of the First Curing Coma Campaign NIH Symposium: Challenging the Future of Research for Coma and Disorders of Consciousness

Coma and disorders of consciousness (DoC) are highly prevalent and constitute a burden for patients, families, and society worldwide. As part of the Curing Coma Campaign, the Neurocritical Care Society partnered with the National Institutes of Health to organize a symposium bringing together experts from all over the world to develop research targets for DoC. The conference was structured along six domains: (1) defining endotype/phenotypes, (2) biomarkers, (3) proof-of-concept clinical trials, (4) neuroprognostication, (5) long-term recovery, and (6) large datasets. This proceedings paper presents actionable research targets based on the presentations and discussions that occurred at the conference. We summarize the background, main research gaps, overall goals, the panel discussion of the approach, limitations and challenges, and deliverables that were identified.

External Validation of the Subarachnoid Hemorrhage International Trialists (SAHIT) Predictive Model Using the Barrow Ruptured Aneurysm Trial (BRAT) Cohort

BACKGROUND

The Subarachnoid Hemorrhage International Trialists (SAHIT) repository is a collection of randomized clinical trials, prospective observational studies, and hospital registries that was used to create a predictive model of unfavorable outcome/mortality following aneurysmal SAH.

OBJECTIVE

To externally validate the SAHIT model using Barrow Ruptured Aneurysm Trial (BRAT) data, which was not included in the SAHIT repository.

METHODS

This is a post hoc analysis of the prospective, randomized BRAT. Three models were created: (1) Core (age, hypertension, World Federation of Neurosurgical Societies grade), (2) neuroimaging (aneurysm size/location, Fisher score), and (3) full model (model 1 and 2 plus treatment type). The performance of the models was evaluated by measures of model discrimination (area under the curve [AUC]) and model calibration (goodness of fit test, calibration in-the-large, calibration slope).

RESULTS

A total of 338 patients (average age 54 years; 67.7% good clinical grade; average aneurysm size 6.7 mm; 84.1% anterior circulation) were included. Due to a large number of crossovers, more aneurysms were clipped than coiled (67.5% vs 32.5%, respectively). A total of 10.1% of the patients died and 29.6% experienced an unfavorable outcome. For unfavorable outcome, the AUCs for the three models were: 0.728, 0.732, and 0.734, respectively. For mortality, the AUCs for the three models were: 0.721, 0.739, and 0.744, respectively. Overall, all models showed good calibration, and the measures of calibration fell within 95% CI of those produced in the SAHIT study.

CONCLUSION

Using the BRAT data, we have externally validated the SAHIT model for predicting unfavorable outcome and mortality after SAH. The model may be used to counsel patients and families on prognosis following aneurysmal SAH.

Loss of consciousness at ictus and/or poor World Federation of Neurosurgical Societies grade on admission reflects the impact of EBI and predicts poor outcome in patients with SAH

Background:

There are many scores and markers that predict poor outcome in patients with subarachnoid hemorrhage (SAH). However, parameters that can predict outcomes in patients with SAH with high specificity and sensitivity, which can be identified in the early postictal state and utilized as a clinical marker of early brain injury (EBI) have not been identified so far.

Methods:

Thirty-nine patients with SAH due to a saccular intracranial aneurysm rupture were reviewed. We retrospectively analyzed the relationships between patients’ baseline characteristics and patients’ outcomes to identify parameters that could predict patient outcomes in the early postictal state.

Results:

In the univariate analysis, older age (>65), loss of consciousness (LOC) at ictus, poor initial World Federation of Neurosurgical Societies (WFNS) grade (3–5), and delayed cerebral ischemia (DCI) were associated with poor outcome (GOS 1–3). Statistical analyses revealed that combined LOC at ictus and/or poor initial WFNS grade (3–5) was a more powerful surrogate marker of outcome (OR 15.2 [95% CI 3.1–75.5]) than either LOC at ictus or the poor initial WFNS grade (3–5) alone. Multivariate logistic regression analyses revealed that older age, combined LOC at ictus and/or poor initial WFNS grade, and DCI were independently associated with poor outcome.

Conclusion:

Combined LOC at ictus and/or poor initial WFNS grade (3–5) reflects the impact of EBI and was a useful surrogate marker of poor prognosis in SAH patients, independent of patients’ age and state of DCI.

Subarachnoid Hemorrhage Pattern Predicts Acute Cerebral Blood Flow Response in the Rat

There is considerable variability in the presentation of patients with acute subarachnoid hemorrhage (aSAH). Evidence suggests that a thick, diffuse clot better predicts the development of delayed cerebral ischemia and poor outcomes. In a rodent model of acute SAH, we directly measured the effects of the volume of blood injected versus the pattern of distribution of hemorrhage in the subarachnoid space on markers of early brain injury, namely, cerebral blood flow (CBF), cerebrospinal fluid (CSF) concentrations of P450 eicosanoids and catecholamines, and cortical spreading depolarizations (CSDs). There is a significant decrease in CBF, an increase in CSF biomarkers, and a trend toward increasing frequency and severity of CSDs when grouped by severity of hemorrhage but not by volume of blood injected. In severe hemorrhage grade animals, there was a progressive decrease in CBF after successive CSD events. These results suggest that the pattern of SAH (thick diffuse clots) correlates with the "clinical" severity of SAH.

Loss of consciousness at onset of aneurysmal subarachnoid hemorrhage in good-grade patients

Loss of consciousness (LOC) at presentation with aneurysmal subarachnoid hemorrhage (aSAH) has been associated with early brain injury and poor functional outcome. The impact of LOC on the clinical course after aSAH deserves further exploration. A retrospective analysis of 149 aSAH patients who were prospectively enrolled in the Cerebral Aneurysm Renin Angiotensin Study (CARAS) between 2012 and 2015 was performed. The impact of LOC was analyzed with emphasis on patients presenting in excellent or good neurological condition (Hunt and Hess 1 and 2). A total of 50/149 aSAH patients (33.6%) experienced LOC at presentation. Loss of consciousness was associated with severity of neurological condition upon admission (Hunt and Hess, World Federation of Neurosurgical Societies (WFNS), Glasgow Coma Scale (GCS) grade), hemorrhage burden on initial head CT (Fisher CT grade), acute hydrocephalus, cardiac instability, and nosocomial infection. Of Hunt and Hess grade 1 and 2 patients, 21/84 (25.0%) suffered LOC at presentation. Cardiac instability and nosocomial infection were significantly more frequent in these patients. In multivariable analysis, LOC was the predominant predictor of cardiac instability and nosocomial infection. Loss of consciousness at presentation with aSAH is associated with an increased rate of complications, even in good-grade patients. The presence of LOC may identify good-grade patients at risk for complications such as cardiac instability and nosocomial infection.

Risk Factors for Mild Cognitive Impairment in Patients with Aneurysmal Subarachnoid Hemorrhage Treated with Endovascular Coiling

OBJECTIVE

To assess the potential early risk factors of mild cognitive impairment after aneurysmal subarachnoid hemorrhage.

METHODS

We prospectively enrolled patients with aneurysmal subarachnoid hemorrhage treated with endovascular coiling during a 5-year period. The demographic characteristics and radiologic and laboratory data were collected. Cognitive assessments were carried out using the Montreal Cognitive Assessment at 6 months after ictus. Multivariate logistic regression was used to determine the risk factors associated with the development of mild cognitive impairment.

RESULTS

Of 152 patients, 59 patients (39%) developed cognitive impairment 6 months later. Univariate analysis showed that the patients with anterior communicating artery or anterior cerebral artery aneurysms (P < 0.001) with Glasgow Outcome Scale score of 7 or less at ictus (P = 0.002), Hunt and Hess grade of 3 or higher (P = 0.002), and Fisher grade of 3 or higher (P = 0.032) were more likely to develop mild cognitive impairment. The risk of mild cognitive impairment was increased for patients who had delayed cerebral ischemia (P = 0.040) and hydrocephalus (P = 0.002). In multivariate logistic regression analysis, mild cognitive impairment was independently associated with anterior communicating artery or anterior cerebral aneurysms (odds ratio [OR], 11.046; 95% confidence interval [CI], 3.371-36.198; P < 0.001), delayed cerebral ischemia (OR, 6.153; 95% CI, 1.587-23.855; P = 0.009), and hydrocephalus (OR, 8.768; 95% CI, 2.115-36.345; P = 0.003).

CONCLUSIONS

The location of the aneurysm, delayed cerebral ischemia, and hydrocephalus were independently associated with the occurrence of mild cognitive impairment after aneurysmal subarachnoid hemorrhage and can contribute to improved identification of patients at high risk for mild cognitive impairment.

Risk Factors for Unfavorable Outcome in Aneurysmal Subarachnoid Hemorrhage Revisited; Odds and Ends

Objectives

To evaluate the odds for unfavorable outcome of each risk factor and a combination of them in patients with aneurysmal subarachnoid hemorrhage (SAH) undergoing surgical clipping in Southern Iran.

Methods

A total of 367 patients who were operated between March 2007 and March 2016 due to aneurysmal SAH were analyzed according to patients' factors, aneurysm characteristics and intra-operative data. Correlation between outcomes of patients measured by modified Rankin Scale at 6-months with each factor were analyzed. Market Basket analysis was also used to identify the odds of unfavorable outcome for combinations of factors.

Results

A total of 367 patients, including 199 females and 168 males with a mean age of 47.27± 11.53 years, who underwent operation between March 2007 and March 2016 due to aneurysmal SAH were analyzed. Unlike gender, higher age was associated with unfavorable outcome. Ischemic heart disease, Duration of operation and amount of bleeding were also found to increase the odds of unfavorable outcome (p=0.01, 0.02, 0.04 respectively). DM, Cigarette smoking and opium addiction as well as the location and multiplicity of aneurysms did not have an adverse effect on outcome. (p≥0.05).

Conclusion

Among the numerous risk factors presumed to result in unfavorable outcome in aneurysmal SAH, only older age, duration of operation more than 60 minutes, previous known history of ischemic heart disease, poorer clinical grade and intra-operative bleeding more than 500 mL were found to be significant factors.

Heparin: The Silver Bullet of Aneurysmal Subarachnoid Hemorrhage?

Various neurological diseases have recently been associated with neuroinflammation and worsening outcomes. Subarachnoid hemorrhage has been shown to generate a potent neuroinflammatory response. Heparin is a potential effective anti-inflammatory agent to prevent initial injury as well as delayed neurological decline. Different mechanisms of action for heparin have been proposed including, but not limited to the binding and neutralization of oxyhemoglobin, decreased transcription and signal transduction of endothelin-1, inhibition of binding to vessel wall selectins and vascular leakage into the subarachnoid space as well as direct binding and neutralization of inflammatory molecules. With a reasonably safe side-effect profile, heparin has shown significant promise in small series in human studies of aneurysmal subarachnoid hemorrhage in decreasing both initial and delayed neurological injury. Further studies are needed to validate various neuroprotective features of heparin in subarachnoid hemorrhage as well as other disease states.

Heparin and Heparin-Derivatives in Post-Subarachnoid Hemorrhage Brain Injury: A Multimodal Therapy for a Multimodal Disease

Pharmacologic efforts to improve outcomes following aneurysmal subarachnoid hemorrhage (aSAH) remain disappointing, likely owing to the complex nature of post-hemorrhage brain injury. Previous work suggests that heparin, due to the multimodal nature of its actions, reduces the incidence of clinical vasospasm and delayed cerebral ischemia that accompany the disease. This narrative review examines how heparin may mitigate the non-vasospastic pathological aspects of aSAH, particularly those related to neuroinflammation. Following a brief review of early brain injury in aSAH and heparin’s general pharmacology, we discuss potential mechanistic roles of heparin therapy in treating post-aSAH inflammatory injury. These roles include reducing ischemia-reperfusion injury, preventing leukocyte extravasation, modulating phagocyte activation, countering oxidative stress, and correcting blood-brain barrier dysfunction. Following a discussion of evidence to support these mechanistic roles, we provide a brief discussion of potential complications of heparin usage in aSAH. Our review suggests that heparin’s use in aSAH is not only safe, but effectively addresses a number of pathologies initiated by aSAH.