The role of transcranial Doppler ultrasonography in the diagnosis and management of vasospasm after aneurysmal subarachnoid hemorrhage

Predictors of Skilled Nursing Facility Length of Stay and Discharge After Aneurysmal Subarachnoid Hemorrhage

Background and Purpose

Aneurysmal subarachnoid hemorrhage (aSAH) carries high morbidity and mortality with survivors often requiring extended care at skilled nursing facilities (SNF). Predictors of SNF discharge to home (SNFdcH) remain unclear.

Methods

Retrospective review of a single-center prospectively maintained aSAH database from June 2016-March 2024 was conducted. Patients discharged to SNF were grouped by subsequent discharge to home. Predictors of discharge to home and facility length of stay (LOS) were determined using t-tests, Fisher analyses, and cumulative link modeling.

Results

Of 450 aSAH patients, 61 (13.5%) were discharged to SNFs. 49 (80.3%) returned home, with 61% achieving mRS <3 at discharge. Discharged patients were younger (mean 63.3 ± 11.5 vs 70.2 ± 9.3 years, P = .040) with lower median modified Fisher scores (3 [IQR 3-4] vs 4 [4-4], P = .046). Tracheostomy (OR = .14, 95% CI [.02, .75], P = .023) and gastrostomy tube (PEG) placement (OR = .13, 95% CI: .03-.51, P = .003) decreased the odds of SNFdcH. Discharged patients had shorter hospital LOS (26 ± 10 vs 39 ± 15 days, P < .001) and lower median modified Rankin scores (mRS) at hospital discharge (4 [4-5] vs 5 [4-5], P = .028) and at 90 days post-discharge (4 [3-5] vs 6 [5-6], P = .001). Multivariable regression identified age, PEG, and hospital LOS as predictors of SNFdcH. Tracheostomy and PEG predicted SNF LOS.

Conclusions

Most aSAH patients discharged from SNFs returned home, with 61% achieving mRS <3. Patients not discharged were medically complex with neurological deficits. These findings may guide care discussions and highlight the role of SNFs in bridging hospitalization and independence.

Establishing normal Lindegaard Ratio in healthy children 10-16 years of age

PURPOSE

Transcranial doppler based diagnostic criteria for cerebral vasospasm are not well established in the pediatric population because there is no published normative data to support the diagnosis. Studies have relied on expert consensus, but the definitions have not been validated in children diagnosed with angiographic evidence of vasospasm. Obtaining normative data is a prerequisite to defining pediatric cerebral vasospasm and the Lindegaard Ratio (LR). In this study, we obtained normative data and calculation of the normal LR from healthy children aged 10-16 years.

METHODS

TCD and carotid ultrasonography was used to measure steady state velocities of both the middle cerebral artery (VMCA) and the extracranial internal cerebral artery (VEICA) in healthy children aged 10-16 years. Demographic information, hemodynamic characteristics and the calculated LR (VMCA/VEICA) was determined for each subject using descriptive statistics.

RESULTS

Of the 26 healthy children, 13 were male and 13 were female. VMCA ranged between 53 and 93 cm/sec. LR ranged between 1 and 2.2 for the cohort. VMCA for both males and females were within 2 standard deviations (SD) of the normal mean flow velocity. As the VMCA velocities approached 2 SD above the mean, LR did not exceed 2.2.

CONCLUSION

Our results help define a threshold for LR which can be used to establish radiographic criteria for cerebral vasospasm in children. Our data suggests that using VMCA criteria alone would overestimate cerebral vasospasm and raises question of whether an LR threshold other than 3 is more appropriate for the cut off between hyperemia versus vasospasm in children.

Effect of Intrathecal Eugenol on Cerebral Vasospasm in an Experimental Subarachnoid Hemorrhage Model

BACKGROUND

Eugenol has various curative properties. It affects the dilatation of cerebral arteries through voltage-dependent Ca2+ channel inhibition. This study is the first to explore the impact of eugenol on neuroprotection and vasospasm in an experimental subarachnoid hemorrhage (SAH) model.

METHODS

Twenty-four adult male Sprague-Dawley rats were indiscriminately separated into 3 groups: the control group (n = 8), the SAH group (n = 8), and the eugenol group (n = 8). A double-bleeding method was used. The eugenol group received intracisternal eugenol (Sigma-Aldrich, St. Louis, MO, USA) at 30 μg/20 μl after induction of SAH. On the day 7, all groups were euthanized. Measurements were taken for basilar artery wall thickness, lumen diameter, serum endothelin-1 (ET-1), and caspase-3 levels.

RESULTS

The eugenol group exhibited significantly lower wall thickness, ET-1, oxidative stress index, and caspase-3 levels compared to the SAH group. In comparison to the control group, the eugenol group showed a higher oxidative stress index along with higher ET-1 and caspase-3 levels, but these differences were not statistically significant. Wall thickness was significantly higher in the eugenol group than in the control group.

CONCLUSIONS

This study represents the first literature exploration of intrathecal eugenol's impact on vasospasm induced after experimental SAH. Administration of intrathecal eugenol demonstrates a positive effect on the treatment of experimental vasospasm as well as on the reduction of oxidative stress and apoptosis.

Diagnostic value of transcranial doppler to predict delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage : To predict delayed cerebral ischemia

BACKGROUND

Transcranial Doppler (TCD) is a technique to assess blood flow velocity in the cerebral arteries. TCD is frequently used to monitor aneurysmal subarachnoid hemorrhage (aSAH) patients. This study compares TCD-criteria for vasospasm and its association with Delayed Cerebral Ischemia (DCI). An overall score based on flow velocities of various intracranial arteries was developed and evaluated.

METHODS

A retrospective diagnostic accuracy study was conducted between 1998 and 2017 with 621 patients included. Mean flow velocity (MFV) of the cerebral artery was measured between 2-5 days and between 6-9 days after ictus. Cutoff values from the literature, new cutoff values, and a new composite score (Combined Severity Score) were used to predict DCI. Sensitivity, specificity, and area under the curve (AUC) were determined, and logistic regression analysis was performed.

RESULTS

The Combined Severity Score showed an AUC 0.64 (95%CI 0.56-.71) at days 2-5, with sensitivity 0.53 and specificity 0.74. The Combined Severity Score had an adjusted Odds Ratio of 3.41 (95CI 1.86-6.32) for DCI. MCA-measurements yielded the highest AUC to detect DCI at day 2-5: AUC 0.65 (95%CI 0.58-0.73). Optimal cutoff MFV of 83 cm/s for MCA resulted in sensitivity 0.73 and specificity 0.50 at days 2-5.

CONCLUSION

TCD-monitoring of aSAH patients may be a valuable strategy for DCI risk stratification. Lower cutoff values can be used in the early phase after the ictus (day 2-5) than are commonly used now. The Combined Severity Score incorporating all major cerebral arteries may provide a meaningful contribution to interpreting TCD measurements.

Highs and Lows: Dysnatremia and Patient Outcomes in Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Disturbances in serum sodium concentration (dysnatremia) are common following aneurysmal subarachnoid hemorrhage (aSAH), but its direct impact on outcomes is not well understood. This study aimed to examine the association between dysnatremia following aSAH and patient outcomes.

METHODS

A retrospective cohort study of consecutive patients with aSAH who were admitted to an academic referral center between 2015 and 2021 was performed. Multivariate logistic regression was used to test the association of dysnatremia and outcomes including modified Rankin Scale score at 3 months after discharge and vasospasm. Multiple linear regression was used to test the association of hospital length of stay and dysnatremia.

RESULTS

We included 320 patients with confirmed aneurysmal etiology (mean [SD] age = 57.8 [14.3] years; 61% female; 70% White). No independent associations were found between hyponatremia or hypernatremia and functional outcome or vasospasm. However, hospital length of stay was longer in patients with hypernatremia (7 more days; 95% confidence interval = 4.4-9.6, P < 0.001) independent of age, Hunt and Hess grade, modified Fisher score, delayed cerebral ischemia, and other hospital complications.

CONCLUSIONS

Although dysnatremia may not directly impact functional outcome or vasospasm risk, hypernatremia may prolong hospital length of stay. Judicious use of hypertonic saline solutions and avoidance of unnecessary dysnatremia in patients with aSAH should be considered.

Neuromonitoring in Children with Cerebrovascular Disorders

BACKGROUND

Cerebrovascular disorders are an important cause of morbidity and mortality in children. The acute care of a child with an ischemic or hemorrhagic stroke or cerebral sinus venous thrombosis focuses on stabilizing the patient, determining the cause of the insult, and preventing secondary injury. Here, we review the use of both invasive and noninvasive neuromonitoring modalities in the care of pediatric patients with arterial ischemic stroke, nontraumatic intracranial hemorrhage, and cerebral sinus venous thrombosis.

METHODS

Narrative review of the literature on neuromonitoring in children with cerebrovascular disorders.

RESULTS

Neuroimaging, near-infrared spectroscopy, transcranial Doppler ultrasonography, continuous and quantitative electroencephalography, invasive intracranial pressure monitoring, and multimodal neuromonitoring may augment the acute care of children with cerebrovascular disorders. Neuromonitoring can play an essential role in the early identification of evolving injury in the aftermath of arterial ischemic stroke, intracranial hemorrhage, or sinus venous thrombosis, including recurrent infarction or infarct expansion, new or recurrent hemorrhage, vasospasm and delayed cerebral ischemia, status epilepticus, and intracranial hypertension, among others, and this, is turn, can facilitate real-time adjustments to treatment plans.

CONCLUSIONS

Our understanding of pediatric cerebrovascular disorders has increased dramatically over the past several years, in part due to advances in the neuromonitoring modalities that allow us to better understand these conditions. We are now poised, as a field, to take advantage of advances in neuromonitoring capabilities to determine how best to manage and treat acute cerebrovascular disorders in children.

Efficacy and safety of remifentanil dose titration to correct the spontaneous hyperventilation in aneurysmal subarachnoid haemorrhage: protocol and statistical analysis for a prospective physiological study

INTRODUCTION

Spontaneous hyperventilation (SHV) is common in aneurysmal subarachnoid haemorrhage (aSAH). The reduction in arterial partial pressure of carbon dioxide (PaCO₂) may change the brain physiology, such as haemodynamics, oxygenation, metabolism and may lead to secondary brain injury. However, how to correct SHV safely and effectively in patients with aSAH has not been well investigated. The aim of this study is to investigate the efficacy and safety of remifentanil dose titration to correct hyperventilation in aSAH, as well as the effect of changes in PaCO₂ on cerebral blood flow (CBF).

METHODS AND ANALYSIS

This study is a prospective, single-centre, physiological study in patients with aSAH. The patients who were mechanically ventilated and who meet with SHV (tachypnoea combined with PaCO₂ <35 mm Hg and pH >7.45) will be enrolled. The remifentanil will be titrated to correct the SHV. The predetermined initial dose of remifentanil is 0.02 μg/kg/min and will be maintained for 30 min, and PaCO₂ and CBF will be measured. After that, the dose of remifentanil will be sequentially increased to 0.04, 0.06, and 0.08 μg/kg/min, and the measurements for PaCO₂ and CBF will be repeated 30 min after each dose adjustment and will be compared with their baseline values.

ETHICS AND DISSEMINATION

This study has been approved by the Institutional Review Board of Beijing Tiantan Hospital, Capital Medical University (KY 2021-006-02) and has been registered at ClinicalTrials.gov. The results of this study will be disseminated through peer-reviewed publications and conference presentations.

TRIAL REGISTRATION NUMBER

NCT04940273.

Cerebral Digital Subtraction Angiography in Acute Intracranial Hemorrhage: Considerations in Critically Ill Children

Cerebrovascular disorders are an important cause of morbidity and mortality in children. Although minimally invasive, cerebral digital subtraction angiography (DSA) has been shown to be safe in children and is a valuable, and perhaps underutilized, technique for the diagnosis and management of pediatric cerebrovascular disorders in the critical care setting. Through a case-based approach, we explore the utility of DSA in critically ill children with acute intracranial hemorrhage (ICH). We discuss the use of DSA in the acute management of aneurysm and arteriovenous malformation rupture as well as cerebral vasospasm. Those caring for critically ill children with acute ICH should consider cerebral DSA as part of a comprehensive approach to the diagnosis and management of these conditions.

Association of pre-admission antihypertensive agents and outcomes in aneurysmal subarachnoid hemorrhage

BACKGROUND

Delayed cerebral ischemia (DCI) and poor functional outcome are common complications in patients who suffer from aneurysmal subarachnoid hemorrhage (aSAH). It has been proposed that pre-admission beta-blocker therapy may lower cerebral vasospasm (cVSP) risk after aSAH; however, this association with other antihypertensives is unknown. We sought to determine the association between antihypertensives and clinical outcomes in aSAH patients.

METHODS

We performed a retrospective study on a prospectively collected cohort of consecutive patients with aSAH who were admitted to an academic center from 2016 to 2021. Association between pre-admission use of antihypertensives and patient outcomes was determined. Primary outcomes included DCI and poor functional outcome at 3 months after discharge defined as modified Rankin scale [mRS] 4-6. The secondary outcome was cVSP identified using transcranial Doppler (TCD).

RESULTS

The cohort consisted of 306 aSAH patients with mean age 57.1 (SD 13.6) years with 187 females (61 %). Although pre-admission use of beta-blockers (OR 0.40, 95 % CI 0.21-80, p = 0.02), calcium channel blockers (OR 0.43, 95 % CI 0.19-0.93, p = 0.035), and thiazide (OR 0.31, 95 % CI 0.11-0.86, p = 0.025) were associated with lower risk of cVSP in univariate analysis, we did not find any association in a multivariate model after adjusting for age. There was no association between any class of antihypertensives and DCI or functional outcome.

CONCLUSION

Pre-admission use of antihypertensive agents may affect TCD findings, however, none of them appear to be independently associated with DCI or functional outcome. Larger prospective studies are needed to establish any potential association.

Identification of Novel Cerebrospinal Fluid Biomarkers for Cognitive Decline in Aneurysmal Subarachnoid Hemorrhage: A Proteomic Approach

Background

Cognitive impairment commonly occurs in aneurysmal subarachnoid hemorrhage (aSAH) survivors. Cerebrospinal fluid (CSF) biomarkers have been proven useful in several central neurological disorders. No such diagnostic biomarkers are available for predicting cognitive impairment after aSAH to date. Here, we aimed to identify novel CSF biomarkers for cognitive deficits after aSAH using an in-depth proteomic approach.

Methods

We applied mass spectrometry with data independent acquisition (DIA) quantification to identify biomarker candidates in CSF samples from a well-characterized cohort comprising patients with impaired cognition (n = 9) and patients with intact cognition (n = 9). The potential biological processes and signaling pathways associated with differential proteins were analyzed using R software. The candidates were further validated in a larger independent cohort (n = 40) using ELISA. The diagnostic utility of these proteins was investigated by using receiver operating characteristic curve analysis.

Results

In total, we identified 628 proteins. The discovery cohort revealed that 115 proteins were differentially expressed in cognitive impairment patients compared to patients with intact cognition (P < 0.05). Independent cohort replication confirmed NCAM2, NPTXR, NRXN2, RELN, and CNTN2 as sensitive and specific candidate biomarkers for disorders of cognition. Lower CSF levels of all biomarker candidates, except RELN, were associated with more pronounced cognitive decline.

Conclusion

We identified and validated five CSF biomarkers for cognitive impairment in aSAH patients. These particular proteins have important predictive and discriminative potential for cognitive impairment in aSAH and could be potential targets for early disease intervention.

Basic Surveillance Parameters Improve the Prediction of Delayed Cerebral Infarction After Aneurysmal Subarachnoid Hemorrhage

Background

To establish a practical risk chart for prediction of delayed cerebral infarction (DCI) after aneurysmal subarachnoid hemorrhage (aSAH) by using information that is available until day 5 after ictus.

Methods

We assessed all consecutive patients with aSAH admitted to our service between September 2008 and September 2015 (n = 417). The data set was randomly split into thirds. Two-thirds were used for model development and one-third was used for validation. Characteristics that were present between the bleeding event and day 5 (i.e., prior to >95% of DCI diagnoses) were assessed to predict DCI by using logistic regression models. A simple risk chart was established and validated.

Results

The amount of cisternal and ventricular blood on admission CT (Hijdra sum score), early sonographic vasospasm (i.e., mean flow velocity of either intracranial artery >160 cm/s until day 5), and a simplified binary level of consciousness score until day 5 were the strongest predictors of DCI. A model combining these predictors delivered a high predictive accuracy [the area under the receiver operating characteristic (AUC) curve of 0.82, Nagelkerke's R² 0.34 in the development cohort]. Validation of the model demonstrated a high discriminative capacity with the AUC of 0.82, Nagelkerke's R² 0.30 in the validation cohort.

Conclusion

Adding level of consciousness and sonographic vasospasm between admission and postbleed day 5 to the initial blood amount allows for simple and precise prediction of DCI. The suggested risk chart may prove useful for selection of appropriate candidates for interventions to prevent DCI.

Leukocytosis and C-Reactive Protein May Predict Development of Secondary Cerebral Vasospasm in Patients with Aneurysmal Subarachnoid Hemorrhage

Background and Objectives: Secondary cerebral vasospasm (CV) with subsequent delayed cerebral ischemia (DCI) after aneurysmal subarachnoid hemorrhage (aSAH) remains an unpredictable pathology. The aim of this retrospective study was to investigate the association between inflammatory parameters, white blood cell (WBC) count, and C-reactive protein plasma levels (CRP) and the occurrence of secondary CV in patients with aSAH. Materials and Methods: The medical records of 201 Intensive Care Unit patients in Riga East University Hospital with aSAH were retrospectively reviewed in a 24-month period. WBC count and CRP values were observed at admission to the hospital and on the third day. According to the inclusion criteria, 117 (48 males) participants were enrolled for further analysis, with average age of 56 ± 15 years (mean ± SD). In total, secondary CV was diagnosed in 21.4% of cases, and DCI in 22.4% of cases. The patients were classified into three groups: SAH-CV group (n = 25), SAH-DCI group (n = 12), and SAH or control group (n = 80), for comparative analysis. Results: We found that SAH-CV patients demonstrated notably higher inflammatory parameters compared to controls: WBC 13.2 ± 3.3 × 10⁹/L vs. 11.2 ± 3.7 × 10⁹/L; p = 0.01 and CRP median 9.3 mg/L vs. 1.9 mg/L; p < 0.001, respectively. We found that the odds of developing CV increased by 5% for each CRP increase of 1 mg/L at admission (OR, 1.05; CI, 1.014–1.087; p = 0.006). Concomitantly, the odds increased by 16% for every rise in WBC count of 1 × 10⁹/L (OR, 1.16; CI, 1.02–1.32; p = 0.02). WBC count was associated with the occurrence of CV with 96% sensitivity and 40% specificity, with a cut off level of 10.015 × 10⁹/L and AUC 0.683; p = 0.006. CRP displayed 54% sensitivity and 90% specificity with a cut off value of 8.9 mg/L and AUC 0.751; p < 0.001. Moreover, higher values of inflammatory parameters at admission correlated with a longer stay in ICU (r = 0.3, p = 0.002 for WBC count and r = 0.305, p = 0.002 for CRP values), and poor outcome (death) was significantly associated with higher CRP values at admission and on the third day (16.1. vs. 2.2. and 57.4. vs. 11.1, p < 0.001, respectively). Higher mortality was detected in SAH-CV patients (32%) compared to controls (6.3%; p < 0.001). Conclusions: Inflammatory parameters such as WBC count and CRP values at admission might be helpful to predict the development of secondary CV.

Systemic Immune-Inflammation Index Predicts Delayed Cerebral Vasospasm After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Delayed cerebral vasospasm is a feared complication of aneurysmal subarachnoid hemorrhage (SAH).

OBJECTIVE

To investigate the relationship of systemic inflammation, measured using the systemic immune-inflammation (SII) index, with delayed angiographic or sonographic vasospasm. We hypothesize that early elevations in SII index serve as an independent predictor of vasospasm.

METHODS

We retrospectively reviewed the medical records of 289 SAH patients for angiographic or sonographic evidence of delayed cerebral vasospasm. SII index [(neutrophils × platelets/lymphocytes)/1000] was calculated from laboratory data at admission and dichotomized based on whether or not the patient developed vasospasm. Multivariable logistic regression and receiver operating characteristic (ROC) analysis were performed to determine the ability of SII index to predict the development of vasospasm.

RESULTS

A total of 246 patients were included in our study, of which 166 (67.5%) developed angiographic or sonographic evidence of cerebral vasospasm. Admission SII index was elevated for SAH in patients with vasospasm compared to those without (P < .001). In univariate logistic regression, leukocytes, neutrophils, lymphocytes, neutrophil-lymphocyte ratio (NLR), and SII index were associated with vasospasm. After adjustment for age, aneurysm location, diabetes mellitus, hyperlipidemia, and modified Fisher scale, SII index remained an independent predictor of vasospasm (odds ratio 1.386, P = .003). ROC analysis revealed that SII index accurately distinguished between patients who develop vasospasm vs those who do not (area under the curve = 0.767, P < .001).

CONCLUSION

Early elevation in SII index can independently predict the development of delayed cerebral vasospasm in aneurysmal SAH.

Predictive value of the transcranial Doppler and mean arterial flow velocity for early detection of cerebral vasospasm in aneurysmal subarachnoid hemorrhage

Objectives

We aimed to predict cerebral vasospasm in acute aneurysmal subarachnoid hemorrhage and to determine the cut-off values of the mean flow velocity by the use of transcranial Doppler.

Methods

A total of 40 patients with acute aneurysmal subarachnoid hemorrhage were included in this study and classified into two groups. The first group was 26 patients (65%) with cerebral vasospasm and the second group was 14 patients (35%) without vasospasm. Initial evaluation using the Glasgow Coma Scale and the severity of aneurysmal subarachnoid hemorrhage was detected by using both the clinical Hunt and Hess and radiological Fisher grading scales. All patients underwent transcranial Doppler evaluations five times in 10 days measuring the mean flow velocities (MFV) of cerebral arteries.

Results

Patients with cerebral vasospasm were associated with significantly higher mean Glasgow Coma Scale score (p = 0.03), significantly higher mean Hunt and Hess scale grades (p = 0.04), with significantly higher mean diabetes mellitus (p = 0.03), significantly higher mean systolic blood pressure and diastolic blood pressure (p = 0.02 and p = 0.005 respectively) and significantly higher MFVs measured within the first 10 days. Logistic regression analysis demonstrated that MFV ≥81 cm/s in the middle cerebral artery is accompanied by an almost five-fold increased risk of vasospasm (OR 4.92, p < 0.01), while MFV ≥63 cm/s in the anterior cerebral artery is accompanied by a three-fold increased risk of vasospasm (OR 3.12, p < 0.01), and MFV ≥42 cm/s in the posterior cerebral artery is accompanied by a two-fold increased risk of vasospasm (OR 2.11, p < 0.05).

Conclusion

Transcranial Doppler is a useful tool for early detection, monitoring, and prediction of post subarachnoid vasospasm and valuable for early therapeutic intervention before irreversible ischemic neurological deficits take place.

Safety of Modified Nimodipine Dosing in Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Nimodipine improves outcomes in patients with aneurysmal subarachnoid hemorrhage (aSAH). However, the impact of alternative dosing strategies on outcome remains unclear.

METHODS

We performed a retrospective cohort study of consecutive patients admitted with aSAH to an academic referral center from 2016 to 2019. Patients with a confirmed aneurysm cause who received nimodipine were included; patients who died or had withdrawal of life-sustaining treatment within 24 hours of admission were excluded. Univariable and multivariable modified Poisson regression models were used to identify predictors of using modified nimodipine dosing (30 mg every 2 hours) versus standard dosing (60 mg every 4 hours). Inverse probability weighted and modified Poisson regression models were used to estimate adjusted risk ratios (RRs) for outcome measures, with poor outcome defined as modified Rankin Scale score 4-6 at 3 months.

RESULTS

We identified 175 patients with aSAH who met eligibility criteria (mean [SD] age = 57 [13.2] years, 62% female, 73% White); 49% (n = 86) received modified nimodipine dosing. A modified dose was used more frequently in women (RR 2.08, 95% confidence interval [CI] 1.11-3.89, P = 0.02), patients with vasospasm (RR 3.47, 95% CI 1.84-6.51, P < 0.001), and patients who required vasopressors (RR 1.73, 95% CI 1.3-2.32, P < 0.001). Modified dosing was not associated with poor functional outcome (inverse probability weighted RR 1.1, 95% CI 0.8-1.4, P = 0.65).

CONCLUSIONS

Modified dosing of nimodipine is well tolerated and may not be associated with worse functional outcome. Prospective studies are needed to better assess the relationship between nimodipine dosing and outcomes in patients with aSAH.

Relationship between Brain Tissue Oxygen Tension and Transcranial Doppler Ultrasonography

BACKGROUND

Multimodal monitoring of intracranial pressure and brain tissue oxygen tension (PbtO₂) have been increasingly used to detect delayed cerebral ischemia (DCI) after subarachnoid hemorrhage. At our center, patients who cannot be easily assessed clinically will undergo intracranial pressure and PbtO₂ monitoring via a NEUROVENT-PTO bolt. We aimed to determine whether the Lindegaard ratios (LRs) computed from transcranial Doppler ultrasonography (TCDU) would correlate with, or can predict, the simultaneously recorded PbtO₂ value.

METHODS

Patients with aneurysmal subarachnoid hemorrhage, PbtO₂ recordings from the middle cerebral artery territory, and simultaneous TCDU scans available from the ipsilateral middle cerebral artery and internal carotid artery from August 2018 to 2019 were included in the present study. The index test result was vasospasm (LR of ≥3) found on TCDU. The reference standard was the presence of regional hypoxia (PbtO₂ <20 mm Hg). The PbtO₂ results were compared with those from computed tomography angiography as a radiological standard. The predictive values were calculated using a contingency table and receiver operating characteristic curve.

RESULTS

A total of 28 patients (6 men and 22 women; age, 59.04 ± 13.75 years) were identified with simultaneous brain tissue oxygen and TCDU recordings available. Of the 28 patients, 7 had cerebral hypoxia (PbtO₂ <20 mm Hg). We found no correlation between the PbtO₂ measurements and simultaneously recorded LRs (r² = 0.048; P = 0.26). A LR of ≥3 had high specificity (95.24%) for hypoxia but relatively low sensitivity (42.86%; P = 0.037).

CONCLUSION

We find TCDU to be specific for predicting cerebral hypoxia (measured via an intraparenchymal probe). Therefore, it could be a useful and noninvasive tool in the context of preventative DCI monitoring. However, given the low sensitivity, the lack of vasospasm on TCDU should not preclude the possibility of the presence of evolving DCI.

Transcranial Doppler ultrasonography in neurological surgery and neurocritical care

Transcranial Doppler (TCD) ultrasonography is an inexpensive, noninvasive means of measuring blood flow within the arteries of the brain. In this review, the authors outline the technology underlying TCD ultrasonography and describe its uses in patients with neurosurgical diseases. One of the most common uses of TCD ultrasonography is monitoring for vasospasm following subarachnoid hemorrhage. In this setting, elevated blood flow velocities serve as a proxy for vasospasm and can herald the onset of ischemia. TCD ultrasonography is also useful in the evaluation and management of occlusive cerebrovascular disease. Monitoring for microembolic signals enables stratification of stroke risk due to carotid stenosis and can also be used to clarify stroke etiology. TCD ultrasonography can identify patients with exhausted cerebrovascular reserve, and after extracranial-intracranial bypass procedures it can be used to assess adequacy of flow through the graft. Finally, assessment of cerebral autoregulation can be performed using TCD ultrasonography, providing data important to the management of patients with severe traumatic brain injury. As the clinical applications of TCD ultrasonography have expanded over time, so has their importance in the management of neurosurgical patients. Familiarity with this diagnostic tool is crucial for the modern neurological surgeon.

Severe cognitive impairment in aneurysmal subarachnoid hemorrhage: Predictors and relationship to functional outcome

BACKGROUND

Cognitive impairment is common after aneurysmal subarachnoid hemorrhage (SAH). However, compared to predictors of functional outcome, meaningful predictors of cognitive impairment are lacking.

OBJECTIVE

Our goal was to assess which factors during hospitalization can predict severe cognitive impairment in SAH patients, especially those who might otherwise be expected to have good functional outcomes. We hypothesized that the degree of early brain injury (EBI), vasospasm, and delayed neurological deterioration (DND) would predict worse cognitive outcomes.

METHODS

We retrospectively reviewed SAH patient records from 2013 to 2019 to collect baseline information, clinical markers of EBI (Fisher, Hunt-Hess, and Glasgow Coma scores), vasospasm, and DND. Cognitive outcome was assessed by Montreal Cognitive Assessment (MoCA) and functional outcomes by modified Rankin Scale (mRS) at hospital discharge. SAH patients were compared to non-neurologic hospitalized controls. Among SAH patients, logistic regression analysis was used to identify predictors of severe cognitive impairment defined as a MoCA score <22.

RESULTS

We screened 288 SAH and 80 control patients. Cognitive outcomes assessed via MoCA at discharge were available in 105 SAH patients. Most of these patients had good functional outcome at discharge with a mean mRS of 1.8±1.3. Approximately 56.2% of SAH patients had MoCA scores <22 compared to 28.7% of controls. Among SAH patients, modified Fisher scale was an independent predictor of cognitive impairment after adjustment for baseline differences (OR 1.638, p=0.043). MoCA score correlated inversely with mRS (r=-0.3299, p=0.0006); however, among those with good functional outcome (mRS 0-2), 48.7% still exhibited cognitive impairment.

CONCLUSIONS

Severe cognitive impairment is highly prevalent after SAH, even among patients with good functional outcome. Higher modified Fisher scale on admission is an independent risk factor for severe cognitive impairment. Cognitive screening is warranted in all SAH patients, regardless of functional outcome.

A New Transcranial Doppler Scoring System for Evaluating Middle Cerebral Artery Stenosis

BACKGROUND AND PURPOSE

Transcranial Doppler (TCD) criteria for cerebrovascular stenosis are only based on velocity with unsatisfactory positive predictive value (PPV) in previous studies. We refined a published scoring system that integrates several characteristics of TCD data in diagnosing middle cerebral artery (MCA) stenosis.

METHODS

Using the TCD-digital subtraction angiography (DSA) database from Stroke Outcomes and Neuroimaging of Intracranial Atherosclerosis (SONIA) trial, velocity, spectrum pattern, diffuse ratio, and asymmetry ratio were assessed. The cutpoints were defined for each parameter and a point value was assigned to each category within that parameter. A summed score was calculated for each MCA. The accuracy was assessed for different cutpoints in predicting ≥50% MCA stenosis measured by DSA. Logistic regression and C-statistics were used for analysis.

RESULTS

A total of 114 MCAs were included in vessel-based and 87 patients were included in patient-based analysis. Compared to the velocity-only cutpoints in SONIA, the score results in much improved PPV while negative predictive value (NPV) remains unchanged. The score based on mean velocity (score 0: <140 cm/s, score 3: ≥140 cm/s), spectrum pattern (score 0: no turbulence; score 1: mild turbulence; 2: significant turbulence), and asymmetry ratio (score 0: ratio <1.5, score 1: ratio 1.5-2; score 2: ratio ≥2.1) has the highest NPV while PPV remains favorable (PPV: 72% [95% CI 54-90%]; NPV: 84% [95% CI: 75-93%], area under curve [AUC]: .76 [95% CI: .66-.86]).

CONCLUSIONS

The multiparameter scoring system incorporating several characteristics of TCD measures yielded higher PPV while maintaining high NPV compared with the single-parameter velocity criteria in diagnosing MCA ≥50% stenosis.

Clinical and experimental aspects of aneurysmal subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage (aSAH) continues to be associated with significant morbidity and mortality despite advances in care and aneurysm treatment strategies. Cerebral vasospasm continues to be a major source of clinical worsening in patients. We intended to review the clinical and experimental aspects of aSAH and identify strategies that are being evaluated for the treatment of vasospasm. A literature review on aSAH and cerebral vasospasm was performed. Available treatments for aSAH continue to expand as research continues to identify new therapeutic targets. Oral nimodipine is the primary medication used in practice given its neuroprotective properties. Transluminal balloon angioplasty is widely utilized in patients with symptomatic vasospasm and ischemia. Prophylactic "triple-H" therapy, clazosentan, and intraarterial papaverine have fallen out of practice. Trials have not shown strong evidence supporting magnesium or statins. Other calcium channel blockers, milrinone, tirilazad, fasudil, cilostazol, albumin, eicosapentaenoic acid, erythropoietin, corticosteroids, minocycline, deferoxamine, intrathecal thrombolytics, need to be further investigated. Many of the current experimental drugs may have significant roles in the treatment algorithm, and further clinical trials are needed. There is growing evidence supporting that early brain injury in aSAH may lead to significant morbidity and mortality, and this needs to be explored further.

A Review of the Management of Cerebral Vasospasm After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Despite decades of research, cerebral vasospasm (CV) continues to account for high morbidity and mortality in patients who survive their initial aneurysmal subarachnoid hemorrhage.

OBJECTIVE

To define the scope of the problem and review key treatment strategies that have shaped the way CV is managed in the contemporary era.

METHODS

A literature search was performed of CV management after aneurysmal subarachnoid hemorrhage.

RESULTS

Recent advances in neuroimaging have led to improved detection of vasospasm, but established treatment guidelines including hemodynamic augmentation and interventional procedures remain highly variable among neurosurgical centers. Experimental research in subarachnoid hemorrhage continues to identify novel targets for therapy.

CONCLUSIONS

Proactive and preventive strategies such as oral nimodipine and endovascular rescue therapies can reduce the morbidity and mortality associated with CV.

Incorporation of Transcranial Doppler into the ED for the neurocritical care patient

INTRODUCTION

In the catastrophic neurologic emergency, a complete neurological exam is not always possible or feasible given the time-sensitive nature of the underlying disease process, or if emergent airway management is indicated. As the neurologic exam may be limited in some patients, the emergency physician is reliant on the assessment of brainstem structures to determine neurological function. Physicians thus routinely depend on advanced imaging modalities to further investigate for potential catastrophic diagnoses. Acquiring these tests introduces the risks of transport as well as delays in managing time-sensitive neurologic processes. A more immediate, non-invasive bedside approach complementing these modalities has evolved: Transcranial Doppler (TCD).

OBJECTIVE

This narrative review will provide a description of scenarios in which TCD may be applicable. It will summarize the sonographic findings and associated underlying pathophysiology in such neurocritical care patients. An illustrated tutorial, along with pearls and pitfalls, is provided.

DISCUSSION

Although there are numerous formalized TCD protocols utilizing four views (transtemporal, submandibular, suboccipital, and transorbital), point-of-care TCD is best accomplished through the transtemporal window. The core applications include the evaluation of midline shift, vasospasm after subarachnoid hemorrhage, acute ischemic stroke, and elevated intracranial pressure. An illustrative tutorial is provided.

CONCLUSIONS

With the wide dissemination of bedside ultrasound within the emergency department, there is a unique opportunity for the emergency physician to utilize TCD for a variety of conditions. While barriers to training exist, emergency physician performance of limited point-of-care TCD is feasible and may provide rapid and reliable clinical information with high temporal resolution.

"Vasospasm mimic" after aneurysmal subarachnoid hemorrhage

BACKGROUND

Secondary brain injuries, such as delayed cerebral infarction (DCI), are the leading causes of disability after subarachnoid hemorrhage (SAH). Detecting DCI may be challenging, especially for patients presenting an altered level of consciousness.

CASE DESCRIPTION

We describe herein the case of a patient who developed acute hemiplegia four days after SAH, with raised blood flow velocities on transcranial Doppler (TCD), compatible with vasospasm. Finally, full work-up, using CT scan with perfusion CT, and continuous EEG, was consistent with non-convulsive seizures.

CONCLUSION

Multiple secondary complications (DCI, seizures, hydrocephalus) may occur after SAH but are clinically difficult to diagnose. A multimodal evaluation (TCD, CT or MRI, EEG) is useful in order to detect and treat late complications.

Traumatic brain injury and intracranial hemorrhage–induced cerebral vasospasm: a systematic review

OBJECTIVE

Little is known regarding the natural history of posttraumatic vasospasm. The authors review the pathophysiology of posttraumatic vasospasm (PTV), its associated risk factors, the efficacy of the technologies used to detect PTV, and the management/treatment options available today.

METHODS

The authors performed a systematic review in accordance with the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines using the following databases: PubMed, Google Scholar, and CENTRAL (the Cochrane Central Register of Controlled Trials). Outcome variables extracted from each study included epidemiology, pathophysiology, time course, predictors of PTV and delayed cerebral ischemia (DCI), optimal means of surveillance and evaluation of PTV, application of multimodality monitoring, modern management and treatment options, and patient outcomes after PTV. Study types were limited to retrospective chart reviews, database reviews, and prospective studies.

RESULTS

A total of 40 articles were included in the systematic review. In many cases of mild or moderate traumatic brain injury (TBI), imaging or ultrasonographic studies are not performed. The lack of widespread assessment makes finding the true overall incidence of PTV a difficult endeavor. The clinical consequences of PTV are important, given the morbidity that can result from it. DCI manifests as new-onset neurological deterioration that occurs beyond the timeframe of initial brain injury. While there are many techniques that attempt to diagnose cerebral vasospasm, digital subtraction angiography is the gold standard. Some predictors of PTV include SAH, intraventricular hemorrhage, low admission Glasgow Coma Scale (GCS) score (< 9), and young age (< 30 years).

CONCLUSIONS

Given these results, clinicians should suspect PTV in young patients presenting with intracranial hemorrhage (ICH), especially SAH and/or intraventricular hemorrhage, who present with a GCS score less than 9. Monitoring and regulation of CNS metabolism following TBI/ICH-induced vasospasm may play an important adjunct role to the primary prevention of vasospasm.

Applications of Transcranial Color-Coded Sonography in the Emergency Department

Transcranial color-coded Doppler sonography is a noninvasive bedside ultrasound application that combines both imaging of parenchymal structures and Doppler assessment of intracranial vessels. It may aid in rapid diagnoses and treatment decision making of patients with intracranial emergencies in point-of-care settings. This pictorial essay illustrates the technical aspects and emergency department applications of transcranial color-coded Doppler sonography, and provides some rationale for implementation of this technique into the emergency department practice.

Temporal evolution of vasospasm and clinical outcome after intra-arterial vasodilator therapy in patients with aneurysmal subarachnoid hemorrhage

Intra-arterial (IA) vasodilator therapy is one of the recommended treatments to minimize the impact of aneurysmal subarachnoid hemorrhage-induced cerebral vasospasm refractory to standard management. However, its usefulness and efficacy is not well established. We evaluated the effect IA vasodilator therapy on middle cerebral artery blood flow and on discharge outcome. We reviewed records for 115 adults admitted to Neurointensive Care Unit to test whether there was a difference in clinical outcome (discharge mRS) in those who received IA infusions. In a subset of 19 patients (33 vessels) treated using IA therapy, we tested whether therapy was effective in reversing the trends in blood flow. All measures of MCA blood flow increased from day -2 to -1 before infusion (maximum Peak Systolic Velocity (PSV) 232.2±9.4 to 262.4±12.5 cm/s [p = 0.02]; average PSV 202.1±8.5 to 229.9±10.9 [p = 0.02]; highest Mean Flow Velocity (MFV) 154.3±8.3 to 172.9±10.5 [p = 0.10]; average MFV 125.5±6.3 to 147.8±9.5 cm/s, [p = 0.02]) but not post-infusion (maximum PSV 261.2±14.6 cm/s [p = .89]; average PSV 223.4±11.4 [p = 0.56]; highest MFV 182.9±12.4 cm/s [p = 0.38]; average MFV 153.0±10.2 cm/s [p = 0.54]). After IA therapy, flow velocities were consistently reduced (day X infusion interaction p<0.01 for all measures). However, discharge mRS was higher in IA infusion group, even after adjusting for sex, age, and admission grades. Thus, while IA vasodilator therapy was effective in reversing the vasospasm-mediated deterioration in blood flow, clinical outcomes in the treated group were worse than the untreated group. There is need for a prospective randomized controlled trial to avoid potential confounding effect of selection bias.

Intraventricular hemorrhage after dural fistula embolization

BACKGROUND AND OBJECTIVES

Dural arteriovenous fistulas are anomalous shunts between dural arterial and venous channels whose nidus is located between the dural leaflets. For those circumstances when invasive treatment is mandatory, endovascular techniques have grown to become the mainstay of practice, choice attributable to their reported safety and effectiveness. We describe the unique and rare case of a dural arteriovenous fistula treated by transarterial embolization and complicated by an intraventricular hemorrhage. We aim to emphasize some central aspects of the perioperative management of these patients in order to help improving the future approach of similar cases.

CASE REPORT

A 59-year-old woman with a previously diagnosed Cognard Type IV dural arteriovenous fistula presented for transarterial embolization, performed outside the operating room, under total intravenous anesthesia. The procedure underwent without complications and the intraoperative angiography revealed complete obliteration of the fistula. In the early postoperative period, the patient presented with clinical signs of raised intracranial pressure attributable to a later diagnosed intraventricular hemorrhage, which conditioned placement of a ventricular drain, admission to an intensive care unit, cerebral vasospasm and a prolonged hospital stay. Throughout the perioperative period, there were no changes in the cerebral brain oximetry. The patient was discharged without neurological sequelae.

CONCLUSION

Intraventricular hemorrhage may be a serious complication after the endovascular treatment of dural arteriovenous fistula. A close postoperative surveillance and monitoring allow an early diagnosis and treatment which increases the odds for an improved outcome.

Follow-up of Vasospasm by Transcranial Doppler Sonography (TCD) in Subarachnoid Hemorrhage (SAH)

Introduction:

Subarachnoid hemorrhage (SAH)represents hemorrhage in the space between arachnoidea and pia mater, due to aneurysm burst, spontaneously or as a consequence of trauma. It is condition that occurs more common in women than men, and its most common complications are rebleeding and vazospasm. As a result of vasospasm, develops ischemia in the portion of brain tissue that can cause additional neurological deficit. Transcranial Doppler Sonography (TCD) is a noninvasive ultrasound diagnostic method that allows monitoring of the state of intracerebral hemodynamics.

Goal:

The goal is to follow the occurrence of vasospasm after SAH, by the TCD method.

Material and methods:

We have analyzed 47 patients with SAH, by analyzing the presence of aneurysm, hypertension and smoking, and by the TCD method monitor the state of intracerebral hemodynamics during the first four days, then in the second and third week.

Results:

SAH was more common in women (61.7%) than men (38.3%), and in the age range from 22 to 64 years. Aneurism was demonstrated in 61.7% of patients, more common in women, with hypertension 68.1% also more common in women and smoking in 87.2% of patients, also more common in women. By TCD method are recorded milder, elevated blood flow velocities at a quarter of patients in the first measurement, during the second measurement at all and it had significantly greater value, and the third measurement also more increased in about a quarter of patients, so that there is a statistically significant difference in the first and second, second and third measurement for each vessel separately, but not between the first and third measurement.

Conclusion:

Predilection factors for SAH are aneurysms, hypertension and smoking. By using TCD method were recorded milder elevated blood flow velocity in the first days of SAH, with about a quarter of patients, significantly greater increase in blood flow velocity during the second week in all patients and also milder increase blood flow velocity in the third week of the start of SAH is a quarter of patients. TCD is the method of choice in the evaluation and management of vasospasm after SAH, which allows the prevention of delayed cerebral ischemia.

Holistic ultrasound in trauma: An update

Holistic ultrasound is a total body examination using an ultrasound device aiming to achieve immediate patient care and decision making. In the setting of trauma, it is one of the most fundamental components of care of the injured patients. Ground-breaking imaging software allows physicians to examine various organs thoroughly, recognize imaging signs early, and potentially foresee the onset or the possible outcome of certain types of injuries. Holistic ultrasound can be performed on a routine basis at the bedside of the patients, at admission and during the perioperative period. Trauma care physicians should be aware of the diagnostic and guidance benefits of ultrasound and should receive appropriate training for the optimal management of their patients. In this paper, the findings of holistic ultrasound in trauma patients are presented, with emphasis on the lungs, heart, cerebral circulation, abdomen, and airway. Additionally, the benefits of ultrasound imaging in interventional anaesthesia techniques such as ultrasound-guided peripheral nerve blocks and central vein catheterization are described.

[Intraventricular hemorrhage after dural fistula embolization]

BACKGROUND AND OBJECTIVES

Dural arteriovenous fistulas are anomalous shunts between dural arterial and venous channels whose nidus is located between the dural leaflets. For those circumstances when invasive treatment is mandatory, endovascular techniques have grown to become the mainstay of practice, choice attributable to their reported safety and effectiveness. We describe the unique and rare case of a dural arteriovenous fistula treated by transarterial embolization and complicated by an intraventricular hemorrhage. We aim to emphasize some central aspects of the perioperative management of these patients in order to help improving the future approach of similar cases.

CASE REPORT

A 59-year-old woman with a previously diagnosed Cognard Type IV dural arteriovenous fistula presented for transarterial embolization, performed outside the operating room, under total intravenous anesthesia. The procedure underwent without complications and the intraoperative angiography revealed complete obliteration of the fistula. In the early postoperative period, the patient presented with clinical signs of raised intracranial pressure attributable to a later diagnosed intraventricular hemorrhage, which conditioned placement of a ventricular drain, admission to an intensive care unit, cerebral vasospasm and a prolonged hospital stay. Throughout the perioperative period, there were no changes in the cerebral brain oximetry. The patient was discharged without neurological sequelae.

CONCLUSION

Intraventricular hemorrhage may be a serious complication after the endovascular treatment of dural arteriovenous fistula. A close postoperative surveillance and monitoring allow an early diagnosis and treatment which increases the odds for an improved outcome.

Through the looking glass: early non-invasive imaging in TBI predicts the need for interventions

Background

Early diagnosis and treatment of traumatic brain injury (TBI) lead to better outcomes. It is difficult to predict which patients benefit from specialised centres, leading to over triage or delay in definitive care. We propose that a non-invasive test comprising optic nerve sheath ultrasound, transcranial Doppler and quantitative papillary reactivity is feasible, correlates with CT findings and may allow for accurate early identification of TBI.

Methods

A 1-year, prospective observation study evaluated a low-risk, non-invasive method of assessing brain injury. Patients underwent a non-invasive neurological examination for trauma, including the above assessments. Data from the three examinations were collected within 6 hours of injury and at 24 hours, and were analysed. Demographics, haemodynamic data, imaging results and short-term outcomes/interventions were recorded.

Results

Trauma patients over the age of 18 years, with a Glascow coma scale (GCS) of <12 or CT evidence of TBI, and intubated were included (N=100). These were divided into +CT (n=49) and −CT groups (n=51) according to the Marshall CT classification of TBI. The +CT group was older, with worse GCS and higher lactate (p=0.008, p=0.001 and p=0.01) but were otherwise well matched. The +CT group included all TBI types, with 96% of the patients having more than one type of TBI. Pulsatility index and neurologic pupillary index were predictive of a +CT (p=0.04, p=0.02). Area under the receiver-operating curve for the logistic regression model for the prediction of positive radiographic findings was r=0.718. Finally, we suggest a preliminary scoring heuristic for predicting a positive radiological finding in a patient with TBI.

Conclusions

The proposed examination is a feasible, non-invasive tool that may have clinical utility in the early prediction of TBI. If validated, it may improve trauma triage for the brain-injured patient. Further studies are warranted to validate this model.

Hematologic counts as predictors of delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage

PURPOSE

Aneurysmal subarachnoid hemorrhage (SAH) is associated with high morbidity and mortality, but currently no single clinical method or ancillary test can reliably predict which subset of patients will develop delayed cerebral ischemia (DCI). The aim of this study was to find hematologic derangements and clinical factors present during the first 7 days after bleeding that could help identify patients at risk for development of DCI.

MATERIALS AND METHODS

Databank analysis of patients with SAH admitted between 2010 and 2012 in a single center. Data from demographics, imaging, laboratory, and clinical factors were collected. Statistical testing was conducted to test for association to the outcome, and multivariate logistic regression was used to design a predictive model.

RESULTS

Of 55 patients, 14 developed DCI (25%). Anemia and leukocytosis on the third day after bleeding were significantly correlated with the outcome (for anemia: P<.032; confidence interval, 1.12-15.16; odds ratio, 4.12; for leukocytosis: P<.046; confidence interval, 1.03-26.13; odds ratio, 5.18). Anemia and leukocytosis were still statistically significant after adjustment for age, sex, modified Fisher scale, and Hunt-Hess scale.

CONCLUSION

The presence of leukocytosis and anemia during the third day after SAH was statistically correlated with the occurrence of DCI.

Beta-blocker therapy and impact on outcome after aneurysmal subarachnoid hemorrhage: a cohort study

OBJECTIVE

Cerebral vasospasm (cVSP) is a frequent complication of aneurysmal subarachnoid hemorrhage (aSAH), with a significant impact on outcome. Beta blockers (BBs) may blunt the sympathetic effect and catecholamine surge associated with ruptured cerebral aneurysms and prevent cardiac dysfunction. The purpose of this study was to investigate the association between preadmission BB therapy and cVSP, cardiac dysfunction, and in-hospital mortality following aSAH.

METHODS

This was a retrospective cohort study of patients with aSAH who were treated at a tertiary high-volume neurovascular referral center. The exposure was defined as any preadmission BB therapy. The primary outcome was cVSP assessed by serial transcranial Doppler with any mean flow velocity ≥ 120 cm/sec and/or need for endovascular intervention for medically refractory cVSP. Secondary outcomes were cardiac dysfunction (defined as cardiac troponin-I elevation > 0.05 μg/L, low left ventricular ejection fraction [LVEF] < 40%, or LV wall motion abnormalities [LVWMA]) and in-hospital mortality.

RESULTS

The cohort consisted of 210 patients treated between February 2009 and September 2010 (55% were women), with a mean age of 53.4 ± 13 years and median Hunt and Hess Grade III (interquartile range III–IV). Only 13% (27/210) of patients were exposed to preadmission BB therapy. Compared with these patients, a higher percentage of patients not exposed to preadmission BBs had transcranial Doppler-mean flow velocity ≥ 120 cm/sec (59% vs 22%; p = 0.003). In multivariate analyses, lower Hunt and Hess grade (OR 3.9; p < 0.001) and preadmission BBs (OR 4.5; p = 0.002) were negatively associated with cVSP. In multivariate analysis, LVWMA (OR 2.7; p = 0.002) and low LVEF (OR 1.1; p = 0.05) were independent predictors of in-hospital mortality. Low LVEF (OR 3.9; p = 0.05) independently predicted medically refractory cVSP. The in-hospital mortality rate was higher in patients with LVWMA (47.4% vs 14.8%; p < 0.001).

CONCLUSIONS

The study data suggest that preadmission therapy with BBs is associated with lower incidence of cVSP after aSAH. LV dysfunction was associated with higher medically refractory cVSP and in-hospital mortality. BB therapy may be considered after aSAH as a cardioprotective and cVSP preventive therapy.

Safety and tolerability of gabapentin for aneurysmal subarachnoid hemorrhage (sah) headache and meningismus

BACKGROUND

Headache after aneurysmal subarachnoid hemorrhage (SAH) is very common and is often described as the "worst headache imaginable." SAH-associated headache can persist for days to weeks and is traditionally treated with narcotics. However, narcotics can have significant adverse effects. We hypothesize that gabapentin (GBP), a non-narcotic neuropathic pain medication, would be safe and tolerable and would reduce narcotic requirements after SAH.

METHODS

We retrospectively reviewed the clinical, radiographic, and laboratory data of SAH patients at the neuroscience intensive care unit at Mayo Clinic in Jacksonville, Florida, from January 2011 through February 2013. Headache intensity was quantified by a visual analog scale score. Total opioid use per day was tabulated using an intravenous morphine equivalents scale. Cerebrospinal fluid was also reviewed when available.

RESULTS

There were 53 SAH patients who were treated with GBP along with other analgesics for headache. Among these SAH patients, 34 (64 %) were women, with a mean age of 54 years (SD 12.3). Severe headache was observed in all SAH patients. GBP dosing was rapidly escalated within days of SAH up to a median of 1,200 mg/day, with a range of 300 mg three times a day to 900 mg three times a day. Approximately 6 % of patients treated with GBP had nausea (95 % CI 1-16 %), and only one patient (1.8 %) had to discontinue GBP.

CONCLUSIONS

GBP appears to be relatively safe and tolerable in SAH patients with headache and may be a useful narcotic-sparing agent to prevent narcotics-associated complications, such as gastrointestinal immobility, ileus, and constipation.

Image-guided transcranial Doppler sonography for monitoring of vasospasm after subarachnoid hemorrhage

OBJECTIVES

Transcranial Doppler ultrasound (TCD) is a standard method for bedside vasospasm monitoring after subarachnoid hemorrhage (SAH). Image guidance has previously been shown to reduce intra- and interobserver variability of this method. The aim of the present study was to compare image-guided and conventional TCD in vasospasm monitoring after SAH.

PATIENTS AND METHODS

418 TCD exams of 24 consecutive SAH patients registered in a database were evaluated. Of these, 130 image-guided exams were identified which had been performed on the same day as conventional Doppler exams. These matched pairs were taken for statistical analysis. Data were tested statistically using the sign test applied at patient level to aggregated data.

RESULTS

The rate of complete exams (both M1, A1, P1 segments) was significantly higher in image-guided exams (92% vs. 74%, p<0.001), and the superiority of image-guided exams was significantly related to smaller sizes of the temporal bone window. There were more exams with Doppler sonographic vasospasm (mean flow velocity>120cm/s) in image-guided exams (38% vs. 33%) which, however, did not reach statistical significance.

CONCLUSION

Image-guidance leads to a standardization of serial TCD exams, which resulted in significantly more complete exams, most prominent in patients with poor temporal bone windows, and a higher detection rate of Doppler sonographic vasospasms. Image-guided TCD therefore has the capability to improve bedside vasospasm monitoring after SAH.

Transcranial Doppler Ultrasound: Physical Principles and Principal Applications in Neurocritical Care Unit

Transcranial Doppler (TCD) ultrasonography is a noninvasive ultrasound study, which has been extensively applied on both outpatient and inpatient settings. It involves the use of a low-frequency (≤2 MHz) transducer, placed on the scalp, to insonate the basal cerebral arteries through relatively thin bone windows and to measure the cerebral blood flow velocity and its alteration in many different conditions. In neurointensive care setting, TCD is useful for both adults and children for day-to-day bedside assessment of critical conditions including vasospasm in subarachnoid hemorrhage, traumatic brain injury, acute ischemic stroke, and brain stem death. It also allows to investigate the cerebrovascular autoregulation in setting of carotid disease and syncope. In this review, we will describe physical principles underlying TCD, flow indices most frequently used in clinical practice and critical care applications in Neurocritical Unit care.

Critical Appraisal of the Milwaukee Protocol for Rabies: This Failed Approach Should Be Abandoned

The Milwaukee protocol has been attributed to survival in rabies encephalitis despite a lack of scientific evidence supporting its therapeutic measures. We have reviewed the literature with reference to specific treatment recommendations made within the protocol. Current literature fails to support an important role for excitotoxicity and cerebral vasospasm in rabies encephalitis. Therapies suggested in the Milwaukee protocol include therapeutic coma, ketamine infusion, amantadine, and the screening/prophylaxis/management of cerebral vasospasm. None of these therapies can be substantiated in rabies or other forms of acute viral encephalitis. Serious concerns over the current protocol recommendations are warranted. The recommendations made by the Milwaukee protocol warrant serious reconsideration before any future use of this failed protocol.

A Review of the Effectiveness of Neuroimaging Modalities for the Detection of Traumatic Brain Injury

The incidence of traumatic brain injury (TBI) in the United States was 3.5 million cases in 2009, according to the Centers for Disease Control and Prevention. It is a contributing factor in 30.5% of injury-related deaths among civilians. Additionally, since 2000, more than 260,000 service members were diagnosed with TBI, with the vast majority classified as mild or concussive (76%). The objective assessment of TBI via imaging is a critical research gap, both in the military and civilian communities. In 2011, the Department of Defense (DoD) prepared a congressional report summarizing the effectiveness of seven neuroimaging modalities (computed tomography [CT], magnetic resonance imaging [MRI], transcranial Doppler [TCD], positron emission tomography, single photon emission computed tomography, electrophysiologic techniques [magnetoencephalography and electroencephalography], and functional near-infrared spectroscopy) to assess the spectrum of TBI from concussion to coma. For this report, neuroimaging experts identified the most relevant peer-reviewed publications and assessed the quality of the literature for each of these imaging technique in the clinical and research settings. Although CT, MRI, and TCD were determined to be the most useful modalities in the clinical setting, no single imaging modality proved sufficient for all patients due to the heterogeneity of TBI. All imaging modalities reviewed demonstrated the potential to emerge as part of future clinical care. This paper describes and updates the results of the DoD report and also expands on the use of angiography in patients with TBI.

Neuromonitoring indications and utility in the intensive care unit

Information on the use of neuromonitoring in intensive care units is scattered but significant. Nurses who do not care for neurologically impaired patients on a daily basis may not have a strong understanding of the utility of various neuromonitoring techniques, why they are used, or how they are interpreted. Two main types of neuromonitoring that are frequently seen but poorly understood are reviewed here: transcranial Doppler sonography and electrophysiology. Information on these 2 techniques tends to be either superficial with limited applicability to the critical care setting or very technical. This review provides information about neuromonitoring to help guide critical care nurses providing care to neurologically impaired patients.

Aneurysmal Subarachnoid Hemorrhage

Aneurysmal subarachnoid hemorrhage (SAH) is a worldwide health burden with high fatality and permanent disability rates. The overall prognosis depends on the volume of the initial bleed, rebleeding, and degree of delayed cerebral ischemia (DCI). Cardiac manifestations and neurogenic pulmonary edema indicate the severity of SAH. The International Subarachnoid Aneurysm Trial (ISAT) reported a favorable neurological outcome with the endovascular coiling procedure compared with surgical clipping at the end of 1 year. The ISAT trial recruits were primarily neurologically good grade patients with smaller anterior circulation aneurysms, and therefore the results cannot be reliably extrapolated to larger aneurysms, posterior circulation aneurysms, patients presenting with complex aneurysm morphology, and poor neurological grades. The role of hypothermia is not proven to be neuroprotective according to a large randomized controlled trial, Intraoperative Hypothermia for Aneurysms Surgery Trial (IHAST II), which recruited patients with good neurological grades. Patients in this trial were subjected to slow cooling and inadequate cooling time and were rewarmed rapidly. This methodology would have reduced the beneficial effects of hypothermia. Adenosine is found to be beneficial for transient induced hypotension in 2 retrospective analyses, without increasing the risk for cardiac and neurological morbidity. The neurological benefit of pharmacological neuroprotection and neuromonitoring is not proven in patients undergoing clipping of aneurysms. DCI is an important cause of morbidity and mortality following SAH, and the pathophysiology is likely multifactorial and not yet understood. At present, oral nimodipine has an established role in the management of DCI, along with maintenance of euvolemia and induced hypertension. Following SAH, hypernatremia, although less common than hyponatremia, is a predictor of poor neurological outcome.

Characterisation of DWI-MRI confirmed cerebral infarcts in patients with subarachnoid haemorrhage and their association with MMP-9 levels

OBJECTIVES

It has been suggested that metalloproteinase-9 (MMP-9) could predict the onset of cerebral vasospasm after subarachnoidal haemorrhage (SAH). The aim of this study was to analyse, in patients with SAH, the difference between patients with MRI ischaemic infarcts and patients without, and to investigate the role of metalloproteases as a prognostic factor for ischaemic infarcts.

METHODS

Sixty eight consecutive patients with SAH and diffusion-weighted magnetic resonance imaging (DWI-MRI) done 3 weeks after SAH. We define two groups, with and without DWI-MRI infarcts. Blood samples were taken at entry, 3 days and 1 week MMP-9 was determined through ELISA method.

RESULTS

Forty per cent were male, with a mean age of 54 ± 14 years. Twenty five patients, 36.8%, had DWI-MRI infarcts; in patients with MRI infarcts, SAH was more severe (Fisher = 4 52 vs 25.6%, P = 0.037), with more morbi-mortality (Rankin>3 48 vs 18.6%, P = 0.014), and more symptomatic vasospasm (28 vs 7%, P = 0.031). Levels of MMP-9 were higher than controls, but there were no significant differences between patients with and without infarcts (first determination no infarcts 39.40 ng/ml ± 35.40 vs infarcts 49.75 ng/ml ± 34.54, P > 0.005, 3 days no infarcts 72.10 ng/ml ± 70.95 vs infarcts 62.28 ± 33.84, P > 0.005, 1 week no infarcts 148.48 ng/ml ± 142.73 vs infarcts 91.5 ng/ml ± 1.20, P > 0.005).

CONCLUSION

Thirty eight percent in a well-studied series of patients with SAH have DWI-MRI infarcts; the infarcts were associated to SAH severity, SAH outcome and symptomatic vasospasm. Metalloproteinase-9 was higher in SAH patients than in controls, but it could not discriminate the infarct patients.

Description of the vasospasm phenomena following perimesencephalic nonaneurysmal subarachnoid hemorrhage

Background. Perimesencephalic nonaneurysmal subarachnoid hemorrhage (PM-NASAH) is characterized by a benign course compared with aneurysmal SAH. While vasospasm (VS) after aneurysmal SAH is considered responsible for serious complications, VS post-PM-NASAH is not well documented. Our purpose was to characterize the incidence and course of VS among 63 patients—one of the largest databases of PM-NASAH patients with documented blood flow velocities in the literature. Methods. Data from 63 patients that were admitted with PM-NASAH from 2000 to 2012 and underwent transcranial Doppler tests to assess cranial vessel flow velocity was analyzed. Results. On average, the maximal flow velocity was measured on the 7th day after hemorrhage. Higher risk for VS was associated with younger age, female sex, and higher Hunt and Hess scores, a lower risk for patients treated with statins (P < 0.05). Using velocity thresholds for diagnosis of VS, 49.2% showed evidence of VS. This is the first description of blood flow velocities in PM-NASAH. VS average onset was on the 4th day, average cessation on day 15 after hemorrhage. No patients showed clinical manifestation of VS. Conclusions. VS post-PM-NASAH is not as rare as previously believed. However, its lack of clinical significance raises questions regarding the need for diagnosis and may suggest a less intensive treatment protocol.

Advances in transcranial Doppler US: imaging ahead

Transcranial Doppler ultrasonography (US) is a noninvasive, portable technique for evaluating the intracranial vasculature. It has found its most useful clinical application in the detection of vasospasm involving the cerebral vessels after subarachnoid hemorrhage due to aneurysm rupture. The technique has become an integral part of monitoring and managing patients with subarachnoid hemorrhage in the neurologic intensive care unit. In addition, it has proved useful for evaluating the intracranial vasculature in patients with sickle cell disease, stroke, or brain death. Transcranial US originated as a "blind" nonimaging study in which pulsed Doppler technology was used. Identification of the major intracranial vessels and evaluation of those vessels for vasospasm relied on spectral waveforms obtained in each vessel and was based on the depth of the vessel from the skull, the direction of blood flow, and the orientation of the transducer. Recent advances in US technology allow the use of gray-scale, spectral Doppler, and color Doppler flow imaging to directly visualize intracranial vessels, thereby simplifying flow velocity measurements and enhancing their accuracy for vasospasm detection. In particular, measurements of peak systolic velocity and mean flow velocity and calculation of the Lindegaard ratio facilitate the identification of vessels that may be in vasospasm and help differentiate vasospasm from physiologic conditions such as hyperemia and autoregulation. Thus, gray-scale and color Doppler flow imaging offer many advantages over the original pulsed Doppler technique for evaluating the intracranial vasculature.