Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism
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J. Cereb. Blood Flow Metab. · Dec 2019
Multicenter Study Clinical TrialDysfunctional cerebral autoregulation is associated with delirium in critically ill adults.
Delirium is common during critical illness and is associated with morbidity and mortality, but its pathophysiology is unknown. We tested whether dysfunctional cerebral autoregulation (CA) contributes to the development of delirium. Adult patients (n = 40) with respiratory failure and/or shock were prospectively enrolled. ⋯ Taking positive COx values to reflect periods of CA dysfunction, we found that the cumulative duration of CA dysfunction during the first one to three days in the ICU was significantly associated with the subsequent development of delirium. Additionally, we assessed two alternative methods for estimating optimal MAP targets in individual patients. In summary, early disturbances in CA may contribute to delirium, and NIRS-derived rSO2 may be used to identify individual perfusion targets in critically ill patients.
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J. Cereb. Blood Flow Metab. · May 2017
Multicenter StudyOxygen availability and spreading depolarizations provide complementary prognostic information in neuromonitoring of aneurysmal subarachnoid hemorrhage patients.
Multimodal neuromonitoring in neurocritical care increasingly includes electrocorticography to measure epileptic events and spreading depolarizations. Spreading depolarization causes spreading depression of activity (=isoelectricity) in electrically active tissue. If the depression is long-lasting, further spreading depolarizations occur in still isoelectric tissue where no activity can be suppressed. ⋯ Multiple regression showed that both peak total depression duration per recording day and mean baseline tissue partial pressure of oxygen were independent predictors of outcome. Moreover, tissue partial pressure of oxygen preceding spreading depolarization was similar and differences in tissue partial pressure of oxygen responses to spreading depolarization were only subtle between isoelectric spreading depolarizations and spreading depressions. This further supports that, similar to clustering of spreading depolarizations, long spreading depolarization-induced periods of isoelectricity are useful to detect energy compromise remotely, which is valuable because the exact location of future developing pathology is unknown at the time when the neurosurgeon implants recording devices.
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J. Cereb. Blood Flow Metab. · Aug 2015
Randomized Controlled Trial Multicenter Study Comparative StudyIntraventricular fibrinolysis with tissue plasminogen activator is associated with transient cerebrospinal fluid inflammation: a randomized controlled trial.
Locally administered tissue plasminogen activator (TPA) accelerates clearance of intraventricular hemorrhage (IVH), but its impact on neurologic outcomes remains unclear and preclinical research suggests it may have pro-inflammatory effects. We randomly allocated patients with ruptured cerebral aneurysms and IVH, treated with endovascular coiling and ventricular drainage, to receive either 2-mg intraventricular TPA or placebo every 12 hours. Cerebrospinal fluid (CSF) and serum cytokine and white blood cell (WBC) concentrations were measured before drug administration and daily for 72 hours. ⋯ Differences were greatest after 24 hours and decreased over 48 to 72 hours. The magnitude of the inflammatory response was significantly associated with peak CSF D-dimer concentration and extent of IVH clearance. We conclude that intraventricular TPA administration produces a transient local inflammatory response, the severity of which is strongly associated with the degree of fibrinolysis, suggesting it may be induced by release of hematoma breakdown products, rather than the drug itself.
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J. Cereb. Blood Flow Metab. · Apr 2013
Multicenter Study Clinical TrialUltrasonographic markers of vascular risk in patients with asymptomatic carotid stenosis.
Six-hundred twenty-one subjects with unilateral asymptomatic severe internal carotid artery (ICA) stenosis were prospectively evaluated with a median follow-up of 27 months (min=6, max=68). Vascular risk profile, plaque characteristic, stenosis progression, and common carotid artery intima-media thickness (IMT) were investigated in all patients. Outcome measures were occurrence of ischemic stroke ipsilateral to ICA stenosis and vascular death, while myocardial infarction, contralateral strokes, and transient ischemic attack were considered as competing events. ⋯ The progression of stenosis was a strong risk factor (hazard ratio=4.32). Finally, the role of carotid IMT was confirmed as crucial additional measure, with an increased risk by 25% for each 0.1 mm IMT increase. Our data suggest that IMT, stenosis progression and severity should be considered as risk factors for cerebrovascular events in asymptomatic subjects with severe ICA stenosis.
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J. Cereb. Blood Flow Metab. · Jan 2013
Multicenter StudyQuantitative measurements of relative fluid-attenuated inversion recovery (FLAIR) signal intensities in acute stroke for the prediction of time from symptom onset.
In acute stroke magnetic resonance imaging, a 'mismatch' between visibility of an ischemic lesion on diffusion-weighted imaging (DWI) and missing corresponding parenchymal hyperintensities on fluid-attenuated inversion recovery (FLAIR) data sets was shown to identify patients with time from symptom onset ≤4.5 hours with high specificity. However, moderate sensitivity and suboptimal interpreter agreement are limitations of a visual rating of FLAIR lesion visibility. We tested refined image analysis methods in patients included in the previously published PREFLAIR study using refined visual analysis and quantitative measurements of relative FLAIR signal intensity (rSI) from a three-dimensional, segmented stroke lesion volume. ⋯ A FLAIR rSI threshold of <1.0721 predicted symptom onset ≤4.5 hours with slightly increased specificity (0.85 versus 0.78) but also slightly decreased sensitivity (0.47 versus 0.58) as compared with visual analysis. Refined visual analysis differentiating between 'subtle' and 'obvious' FLAIR hyperintensities and classification and regression tree algorithms combining information from visual and quantitative analysis also did not improve diagnostic accuracy. Our results raise doubts whether the prediction of stroke onset time by visual image judgment can be improved by quantitative rSI measurements.