Brain temperature regulation in poor-grade subarachnoid hemorrhage patients – A multimodal neuromonitoring study

Elevated body temperature (Tcore) is associated with poor outcome after subarachnoid hemorrhage (SAH). Brain temperature (Tbrain) is usually higher than Tcore. However, the implication of this difference (Tdelta) remains unclear. We aimed to study factors associated with higher Tdelta and its association with outcome. We included 46 SAH patients undergoing multimodal neuromonitoring, for a total of 7879 h of averaged data of Tcore, Tbrain, cerebral blood flow, cerebral perfusion pressure, intracranial pressure and cerebral metabolism (CMD). Three-months good functional outcome was defined as modified Rankin Scale ≤2. Tbrain was tightly correlated with Tcore (r = 0.948, p < 0.01), and was higher in 73.7% of neuromonitoring time (Tdelta +0.18°C, IQR −0.01 – 0.37°C). A higher Tdelta was associated with better metabolic state, indicated by lower CMD-glutamate ( p = 0.003) and CMD-lactate ( p < 0.001), and lower risk of mitochondrial dysfunction (MD) (OR = 0.2, p < 0.001). During MD, Tdelta was significantly lower (0°C, IQR −0.2 – 0.1; p < 0.001). A higher Tdelta was associated with improved outcome (OR = 7.7, p = 0.002). Our study suggests that Tbrain is associated with brain metabolic activity and exceeds Tcore when mitochondrial function is preserved. Further studies are needed to understand how Tdelta may serve as a surrogate marker for brain function and predict clinical course and outcome after SAH

Recording, analysis, and interpretation of spreading depolarizations in neurointensive care: Review and recommendations of the COSBID research group

Spreading depolarizations (SD) are waves of abrupt, near-complete breakdown of neuronal transmembrane ion gradients, are the largest possible pathophysiologic disruption of viable cerebral gray matter, and are a crucial mechanism of lesion development. Spreading depolarizations are increasingly recorded during multimodal neuromonitoring in neurocritical care as a causal biomarker providing a diagnostic summary measure of metabolic failure and excitotoxic injury. Focal ischemia causes spreading depolarization within minutes. Further spreading depolarizations arise for hours to days due to energy supply-demand mismatch in viable tissue. Spreading depolarizations exacerbate neuronal injury through prolonged ionic breakdown and spreading depolarization-related hypoperfusion (spreading ischemia). Local duration of the depolarization indicates local tissue energy status and risk of injury. Regional electrocorticographic monitoring affords even remote detection of injury because spreading depolarizations propagate widely from ischemic or metabolically stressed zones; characteristic patterns, including temporal clusters of spreading depolarizations and persistent depression of spontaneous cortical activity, can be recognized and quantified. Here, we describe the experimental basis for interpreting these patterns and illustrate their translation to human disease. We further provide consensus recommendations for electrocorticographic methods to record, classify, and score spreading depolarizations and associated spreading depressions. These methods offer distinct advantages over other neuromonitoring modalities and allow for future refinement through less invasive and more automated approaches

Worldwide Organization of Neurocritical Care: Results from the PRINCE Study Part 1

Introduction: Neurocritical care focuses on the care of critically ill patients with an acute neurologic disorder and has grown significantly in the past few years. However, there is a lack of data that describe the scope of practice of neurointensivists and epidemiological data on the types of patients and treatments used in neurocritical care units worldwide. To address these issues, we designed a multicenter, international, point-prevalence, cross-sectional, prospective, observational, non-interventional study in the setting of neurocritical care (PRINCE Study). Methods: In this manuscript, we analyzed data from the initial phase of the study that included registration, hospital, and intensive care unit (ICU) organizations. We present here descriptive statistics to summarize data from the registration case report form. We performed the Kruskal–Wallis test followed by the Dunn procedure to test for differences in practices among world regions. Results: We analyzed information submitted by 257 participating sites from 47 countries. The majority of those sites, 119 (46.3%), were in North America, 44 (17.2%) in Europe, 34 (13.3%) in Asia, 9 (3.5%) in the Middle East, 34 (13.3%) in Latin America, and 14 (5.5%) in Oceania. Most ICUs are from academic institutions (73.4%) located in large urban centers (44% > 1 million inhabitants). We found significant differences in hospital and ICU organization, resource allocation, and use of patient management protocols. The highest nursing/patient ratio was in Oceania (100% 1:1). Dedicated Advanced Practiced Providers are mostly present in North America (73.7%) and are uncommon in Oceania (7.7%) and the Middle East (0%). The presence of dedicated respiratory therapist is common in North America (85%), Middle East (85%), and Latin America (84%) but less common in Europe (26%) and Oceania (7.7%). The presence of dedicated pharmacist is highest in North America (89%) and Oceania (85%) and least common in Latin America (38%). The majority of respondents reported having a dedicated neuro-ICU (67% overall; highest in North America: 82%; and lowest in Oceania: 14%). Conclusion: The PRINCE Study results suggest that there is significant variability in the delivery of neurocritical care. The study also shows it is feasible to undertake international collaborations to gather global data about the practice of neurocritical care

Recording, analysis, and interpretation of spreading depolarizations in neurointensive care : Review and recommendations of the COSBID research group

Spreading depolarizations (SD) are waves of abrupt, near-complete breakdown of neuronal transmembrane ion gradients, are the largest possible pathophysiologic disruption of viable cerebral gray matter, and are a crucial mechanism of lesion development. Spreading depolarizations are increasingly recorded during multimodal neuromonitoring in neurocritical care as a causal biomarker providing a diagnostic summary measure of metabolic failure and excitotoxic injury. Focal ischemia causes spreading depolarization within minutes. Further spreading depolarizations arise for hours to days due to energy supply-demand mismatch in viable tissue. Spreading depolarizations exacerbate neuronal injury through prolonged ionic breakdown and spreading depolarization-related hypoperfusion (spreading ischemia). Local duration of the depolarization indicates local tissue energy status and risk of injury. Regional electrocorticographic monitoring affords even remote detection of injury because spreading depolarizations propagate widely from ischemic or metabolically stressed zones; characteristic patterns, including temporal clusters of spreading depolarizations and persistent depression of spontaneous cortical activity, can be recognized and quantified. Here, we describe the experimental basis for interpreting these patterns and illustrate their translation to human disease. We further provide consensus recommendations for electrocorticographic methods to record, classify, and score spreading depolarizations and associated spreading depressions. These methods offer distinct advantages over other neuromonitoring modalities and allow for future refinement through less invasive and more automated approaches

Recording, analysis, and interpretation of spreading depolarizations in neurointensive care: Review and recommendations of the COSBID research group

Spreading depolarizations (SD) are waves of abrupt, near-complete breakdown of neuronal transmembrane ion gradients, are the largest possible pathophysiologic disruption of viable cerebral gray matter, and are a crucial mechanism of lesion development. Spreading depolarizations are increasingly recorded during multimodal neuromonitoring in neuro-critical care as a causal biomarker providing a diagnostic summary measure of metabolic failure and excitotoxic injury. Focal ischemia causes spreading depolarization within minutes. Further spreading depolarizations arise for hours to days due to energy supply-demand mismatch in viable tissue. Spreading depolarizations exacerbate neuronal injury through prolonged ionic breakdown and spreading depolarization-related hypoperfusion (spreading ischemia). Local duration of the depolarization indicates local tissue energy status and risk of injury. Regional electrocorticographic monitoring affords even remote detection of injury because spreading depolarizations propagate widely from ischemic or metabolically stressed zones; characteristic patterns, including temporal clusters of spreading depolarizations and persistent depression of spontaneous cortical activity, can be recognized and quantified. Here, we describe the experimental basis for interpreting these patterns and illustrate their translation to human disease. We further provide consensus recommendations for electrocorticographic methods to record, classify, and score spreading depolarizations and associated spreading depressions. These methods offer distinct advantages over other neuromonitoring modalities and allow for future refinement through less invasive and more automated approaches