bluuebunny/crossref_metadata_2025_split huggingface dataset:
Coughing up blood: Massive hemoptysis
Authors: Garrison Jeremiah , Hypes Cameron 
Published: November 2023

Abstract
This chapter reviews the presentation and management of hemoptysis in the emergency department. The most common causes of hemoptysis are infection, malignancy, and trauma. Airway hemorrhage can cause significant hypoxic respiratory failure, and this will require modification of typical routine airway management. Care for the patient presenting with hemoptysis first involves stratifying the bleeding as mild, moderate, or massive. Initial management is to assess for airway patency, adequacy of gas exchange, and work of breathing. The mainstays of treatment of a patient with severe airway hemorrhage are early intubation, correction of coagulopathy, administration of positive end-expiratory pressure on mechanical ventilation, positioning with the affected side down, and early consultation for computed tomographic angiography and bronchoscopic-guided therapies.
I still can’t breathe: ARDS and advanced ventilation strategies
Authors: Miller Ashley , Dahn Cassidy 
Published: November 2023

Abstract
Acute respiratory distress syndrome (ARDS) is a disease process with an insidious onset associated with high morbidity and mortality. It is most often seen in patients with sepsis, pneumonia, and aspiration. Appropriate ventilation management is the mainstay of treatment, with a focus on low tidal volumes of less than or equal to 6 cc/kg of predicted body weight. Additional ventilation strategies include utilizing high peak end-expiratory pressure (PEEP) and limiting inspired oxygen content (FiO2) while maintaining oxygen saturation and low plateau airway pressures. For refractory ARDS, other options include proning, neuromuscular blockade, recruitment maneuvers, and extracorporeal membrane oxygenation.
It’s getting harder to breathe: Refractory ARDS and VV-ECMO
Authors: Mackay Fraser 
Published: November 2023

Abstract
Severe acute respiratory distress syndrome (ARDS) can present abruptly and needs aggressive management. A small number of patients who have refractory ARDS are salvageable with the use of veno-venous extracorporeal membrane oxygenation (VV-ECMO), which bypasses the patient’s injured lungs to provide temporary gas exchange. Patients should undergo timely evaluation and transfer to capable centers, with the understanding that evidence-based and aggressive ARDS care will set these patients up for the best chance of success for salvage. Patient selection is key to good VV-ECMO outcomes, and teams should weigh the possible benefit of the therapy against its high resource utilization, cost, and invasive nature.
The engine isn’t working: Cardiogenic shock states
Authors: Rowan Daniel J. 
Published: November 2023

Abstract
Cardiogenic shock is defined as systemic hypoperfusion with impaired tissue oxygen delivery as a result of reduced cardiac output and may quickly spiral into multisystem organ failure. While acute coronary syndrome (ACS) is still the leading etiology, a growing percentage of cases result from progression of baseline cardiomyopathy. The clinical exam can be augmented by ultrasonographic assessment focusing on cardiac function, volume status, and presence of pulmonary edema or pleural effusions. Early treatment should focus on supporting a patient’s hemodynamics, guided by ultrasound findings, along with provision of ventilatory support. Definitive treatment relies upon reversing the underlying cause, with particular emphasis on early culprit lesion–guided percutaneous coronary intervention for ACS. Patients with refractory cardiogenic shock should undergo urgent evaluation for candidacy for mechanical circulatory support devices as a bridge to recovery, ventricular assist device, or heart transplant.
A pump replacement: The bleeding LVAD patient
Authors: Gordon Alexandra June , Phillips Andrew W. 
Published: November 2023

Abstract
If a patient with a left ventricular assist device (LVAD) presents to the ED with a gastrointestinal bleed, the management can be complicated. LVAD patients are anticoagulated and often coagulopathic from the device itself, so gastrointestinal bleeding is a common presentation. Assessment of hemodynamics in an LVAD patient requires a Doppler to assess the mean arterial pressure as well as an interrogation of the LVAD controller. These patients are sensitive to decreases in preload and increases in afterload, so resuscitation should be tailored accordingly. Special consideration should be given to reversing anticoagulation in these patients, and the LVAD team should be contacted early and communicated with frequently.
Choked off: Tamponade
Authors: Krieger Josh , Jain Ashika 
Published: November 2023

Abstract
Cardiac tamponade can present insidiously with nonspecific symptoms of dyspnea and tachycardia. Findings on exam can include cool extremities and peripheral edema with elevated jugular venous pressure. Chest radiography may demonstrate clear lungs with an enlarged cardiac silhouette. ECG may show low-amplitude QRS complexes with beat-to-beat variability in amplitude. Pericardial effusions are diagnosed with transthoracic echocardiography, and the first sign of tamponade is right atrial collapse during systole, followed by diastolic collapse of the right ventricle. Severity of tamponade can be judged by the presence of hypotension as well as the duration of right atrial collapse throughout the cardiac cycle. Tamponade can be temporized by administration of intravenous volume and is treated with pericardiocentesis.
Brain plumbing problems: Ischemic versus hemorrhagic strokes
Authors: Lentz Skyler , Marcolini Evie 
Published: November 2023

Abstract
Stroke symptoms can vary and change over time, so the emergency physician must determine the timing of onset, perform a thorough neurologic exam (using the National Institutes of Health Stroke Scale), and obtain initial CT imaging to determine whether the stroke is of ischemic or hemorrhagic origin. Treatments, including reaching blood pressure targets, potential referral for mechanical thrombectomy (ischemic strokes), and reversal or initiation of anticoagulation, are all predicated on accurate timing and diagnosis. Emergency clinicians must also be familiar with the care of ischemic and hemorrhagic stroke patients beyond the first few hours in case there are delays in transfer.
The worst headache of my life: Subarachnoid hemorrhage
Authors: Fontenette Roderick W. , Branting Andrew J. 
Published: November 2023

Abstract
Spontaneous subarachnoid hemorrhage (SAH) is an uncommon neurologic emergency afflicting 1% of patients presenting to EDs with an acute headache. Despite being a low-frequency diagnosis, it requires a high index of suspicion and a thoughtful practitioner’s care as the disease carries a variety of presentations and the associated morbidity and mortality is high. Specifically with aneurysmal SAH, the mortality nears 50% on initial presentation and increases to 80% if rebleeding occurs. A substantial proportion of survivors suffer residual functional impairments. Morbidity and mortality associated with aneurysmal SAH can be greatly impacted with timely detection and appropriate management. The goal is to secure the source of bleeding within 24 hours, and it is recommended to do so with early consideration of transfer to a high-volume comprehensive stroke center equipped with neurovascular interventionalists and familiarity with vasospasm management.
Stop the bleed: Procedures for hemostatic control
Authors: Ramzy Mark M. 
Published: November 2023

Abstract
Hemorrhage control is a vital skill that all emergency physicians will use frequently and must master. When left untreated, acute blood loss and the ensuing hypovolemic shock is the leading cause of preventable death following trauma. The degree of complexity can vary based on the location and source of the bleeding. Whether the bleeding is due to epistaxis or a traumatic injury, all emergency physicians must have a well-devised strategy that includes stepwise interventions to achieve hemostatic control. Approaches should include an arsenal of combined treatments such as direct pinpoint pressure, chemically infused gauze, pharmacotherapy, and tampon or balloon inflation.
Transplant troubles: Managing post-transplant complications
Authors: Murali Shyam , Owyang Clark G. 
Published: November 2023

Abstract
Patients who have received solid organ transplants are at risk for rejection of the transplanted organ as well as adverse effects of the immunosuppressant medications they are taking to prevent rejection. Transplant rejection occurs when the recipient’s immune system destroys the tissue that has been transplanted. To prevent this, many patients are on a lifelong regimen of immunosuppressive medications. The adverse effects of these medications are numerous but notably include infections, which can lead to severe illness and organ failure. Emergency physicians must understand the approach to recognizing complications of transplantation early and must be equipped to treat the acute problems.
Thalamus and Prethalamus Cell Types and Their Interconnections
Authors: Bickford Martha 
Published: November 2023

Abstract
The interconnected neurons of the thalamus and prethalamus can be divided into 3 basic categories: (1) glutamatergic thalamic projection neurons that innervate the cortex and prethalamic reticular nucleus (TRN), and often other forebrain regions such as the striatum, and amygdala; (2) GABAergic intrinsic interneurons that form synaptic connections only within their nucleus of origin; and (3) GABAergic TRN neurons that are reciprocally connected with each thalamic nucleus. As briefly reviewed in this chapter, these 3 basic categories of neurons can be further subdivided based on gene and protein expression, developmental origin, soma size, dendritic morphology, physiological properties, axonal projection patterns, and synaptic connections. Nonetheless, the fundamental circuit patterns formed between these 3 categories of neurons are shared across thalamic nuclei. For example, intrinsic interneurons form dendrodendritic synaptic connections with projection neurons and interneurons in tightly entwined synaptic arrangements termed glomeruli, while TRN neurons are connected to projection neurons via reciprocal axonal projections to and from each thalamic nucleus. A description of these 3 essential thalamic elements sets the stage for the subsequent chapters of this book that describe wide-ranging features that underlie the dynamic interplay between the thalamus and the cortex.
Biophysical Properties of Cortical Excitatory Neurons
Authors: Palmer Lucy M. 
Published: November 2023

Abstract
The capability of the cortex to receive and integrate information from various sources is at the core of brain function. As the most abundant cell type in the cortex, excitatory pyramidal neurons are critical for cortical function. Cortical neurons have specialized input/output patterns and biophysical properties which enhance their integrative and computational capabilities. In this chapter, the properties of cortical excitatory neurons will be explored, detailing the morphology, ion channel distribution, and firing modes. The dendritic integration of input will also be discussed, focusing on the integration of different thalamic input in cortical dendrites. Understanding overall brain function requires detailed knowledge of cortical functioning, including detailed knowledge about the biophysical properties of cortical excitatory neurons and how synaptic input is integrated within their dendrites.
Functional Roles of Cortical Inhibitory Interneurons
Authors: Shin Hyeyoung , Adesnik Hillel 
Published: November 2023

Abstract
This chapter describes how distinct classes of cortical inhibitory interneurons (INs) mediate unique aspects of cortical computation. First, it details how INs can be classified into discrete cell types based on their morphology, cellular physiology, gene expression, and synaptic connectivity. Next, it discusses how different IN classes shape cortical dynamics through their control of excitation-inhibition balance, their role in generating neural oscillations, and their modulation by brain state and arousal. Finally, it surveys INs’ functional role in neocortical computations, with a primary focus on sensory processing. While a series of exciting discoveries in the past decade have linked specific IN classes to specific cortical computations, more recent experimental and theoretical work suggests that most cortical computations are carried out by the interactions between multiple types of INs. The chapter highlights a specific computation that has been heavily researched and yet remains unsolved: the question of how inhibition shapes excitatory principal cells’ feature selectivity. The chapter concludes with a proposal for a general approach to understanding IN contributions in light of the complexity, and highlight several key unanswered questions in cortical function that could be solved by employing a more holistic approach to understanding IN roles in cortical computations.
Thalamic Output Pathways
Authors: Clasca Francisco 
Published: November 2023

Abstract
An accurate cell-level of description of the thalamic output circuits is key for modeling the interactions between thalamus and cortex. Until recently, however, it was not technically possible to delineate the full morphology of individual projection neurons, from their parent cell bodies to all their distant terminal branches. Thus, thalamic output pathways remained loosely defined as cell or axon populations. New single-cell labeling methods have in recent years made it possible to delineate individual thalamic projection neuron morphologies in full. Applied to date almost exclusively in rodents, these new methods are revealing an unsuspected cell diversity. While differences in axon wiring motifs are the most prominent, relevant variations have also been observed in the projection neuron somatodendritic architecture. Other studies are exploring projection neuron gene expression and membrane properties at the single-cell level. Together, these data provide the basis for a robust classification of thalamic projection neurons into several high-level cell classes.
Structure and Function of Corticothalamic Pathways of Layer 6 Neurons
Authors: Murphy Allison J. , Briggs Farran 
Published: November 2023

Abstract
Throughout the brain, corticothalamic (CT) neurons project from layer 6 of the cerebral cortex to various regions of the thalamus, including first-order thalamic nuclei that receive input from the sensory periphery and higher-order thalamic nuclei that derive their inputs mainly from cortical areas. Layer 6 CT neurons are diverse in terms of their cellular morphology and physiological properties, and they likely subserve a number of heterogeneous functions. While the number of synapses originating from layer 6 CT neurons onto thalamic cells is large, their terminals are distally located, small in size, and produce small, facilitating excitatory postsynaptic potentials, all characteristics that define these synaptic interactions as “modulatory” rather than “driving.” Importantly, layer 6 CT circuits often include axon collaterals that target inhibitory neuronal populations within the thalamus, enabling CT feedback to dynamically regulate the balance of excitation and inhibition among thalamic neurons. Although much is yet to be learned about the function of layer 6 CT feedback in the thalamus, current evidence from sensory systems suggests that CT feedback can shape the tuning properties of thalamic neurons as well as influence the timing and precision with which thalamic cells encode incoming sensory information. Other functions of layer 6 CT feedback include regulating arousal state, attention, and sleep. Overall, layer 6 CT pathways provide diverse inputs to thalamus that are likely critical for multiple aspects of brain function.
A Comparative Approach to Parallel Geniculocortical Pathways
Authors: Solomon Samuel G. 
Published: November 2023

Abstract
The dorsal lateral geniculate nucleus of the thalamus (LGN) occupies a central locus in both the passage of visual signals from retina to cortex and in the development of theories for vision. Six decades of research, in several mammalian species, have allowed deep empirical understanding of the structure, connections, and functional properties of the LGN. This work supports the idea that LGN is organized into compartments with different afferent inputs, projections, and functional properties; that is, signals are conveyed from retina to cortex through parallel channels. The aim of this chapter is to develop a comparative, historical overview of this work, and to help the reader understand some of the key debates.
Thalamic Contributions to Visual Cortical Receptive Fields
Authors: O’Shea Ronan , Severson Mandi C. , Priebe Nicholas J. 
Published: November 2023

Abstract
The thalamocortical projection has been linked to many of the canonical computations in primary visual cortex (V1). Across mammals, functionally segregated thalamocortical projections provide the basis for parallel processing streams of visual information in the cortex. The emergent selectivities for orientation and motion direction are shaped by the spatiotemporal response properties of geniculate afferents converging onto single V1 cells. At the population level, the pattern of thalamocortical convergence may also play a role in the formation of the columnar architecture characteristic of V1. The thalamocortical pathways therefore provide essential scaffolds that guide the emergence of novel visual representations in V1.
Visual Processing in the Pulvinar
Authors: Fan Angela Y. , Bourne James A. 
Published: November 2023

Abstract
The enigmatic pulvinar nuclei of the thalamus are an often-overlooked central component of the visual system. However, throughout the evolution of the Euarchontoglires, the pulvinar has dramatically expanded in size, architecture, function, and connectivity, unlike any other nucleus of the thalamus. This chapter provides an overview of past and present research efforts, primarily in primates, including humans, on aspects of pulvinar function relating to visual processing. This is illustrated through multiple anatomical, electrophysiological, imaging, and behavioral studies that sketch a more replete picture. Further, the authors unpack the specific functions of the dynamic and elaborate reciprocal connectivity profile the visual pulvinar nuclei have with the cortex, which underpins high-level visual processing and primate-specific adaptations. These features are especially highlighted during development, where the pulvinar nuclei advance the rapid maturation of specific visual cortices and associated visuomotor behaviors, obviating a developmental bottleneck in the anthropoid primates. Finally, they discuss the significance of the pulvinar following clinical and experimental visual cortical lesions and how these studies have facilitated understanding of the potency of the pulvinar to act as an indispensable architect of vision in the absence of the primary visual circuit (retinogeniculostriate pathway).
Sensory Representations in the Auditory Cortex and Thalamus
Authors: Linden Jennifer F. 
Published: November 2023

Abstract
What are the similarities and differences between sensory representations in the auditory cortex and thalamus—and what do they imply about thalamocortical transformations in the auditory system? This chapter reviews studies that have addressed these questions by comparing auditory cortical and thalamic sound representations at the single-neuron and neuronal-population levels. The studies have used a diversity of stimulus sets and approaches: simple sounds to evaluate frequency tuning and modulation sensitivity; complex artificial sounds to estimate spectrotemporal receptive fields and nonlinear response functions; sound sequences to measure effects of stimulus probability and patterning; and natural sounds to examine responses to ecologically relevant vocalizations and ambient noise. However, key findings converge to the conclusion that, like auditory brainstem nuclei and midbrain structures, the auditory thalamus and cortex are specialized for analysis of temporal information in sensory signals over multiple timescales.
The Role of the Thalamus for Human Auditory and Visual Speech Perception
Authors: von Kriegstein Katharina , Müller-Axt Christa 
Published: November 2023

Abstract
Most speech and language neuroscience research is focused on the cerebral cortex. There are 2 strong contributing factors to this cortico-centric view. First, historically our understanding of human brain function has relied on neuropsychological cases with cerebral cortex lesions. The fascinating case reports of, for example, Broca and Wernicke have been particularly prominent in the development of speech and language neuroscience. Second, for a long time, assessment of brain function in tiny thalamic nuclei in humans in vivo was technically impossible. Fortunately, recent technological advances such as high-spatial-resolution neuroimaging as well as deep brain stimulation now make it possible to investigate the thalamus, its subdivisions, and connections to the cerebral cortex in humans in vivo. This chapter summarizes how these novel developments contribute to understanding of the role of thalamic nuclei and their interaction with cerebral cortex in auditory and visual speech perception. The results reveal that sensory thalamic nuclei are part of a hierarchical predictive coding mechanism that supports speech recognition in the auditory and the visual modality. Alterations in this mechanism might lead to difficulties with speech perception, such as those observed in developmental dyslexia.
Corticothalamic Interactions in the Auditory System
Authors: Bajo Victoria M. , King Andrew J. 
Published: November 2023

Abstract
The medial geniculate body (MGB) or auditory thalamus comprises both first-order and higher-order subdivisions, each of which has a distinct pattern of thalamocortical connections. Pyramidal neurons in layer 6 link each area of the auditory cortex with the region of the thalamus from which it receives most of its ascending input, forming a series of modulatory feedback loops, whereas layer 5 pyramidal neurons have non-reciprocal corticothalamic projections that may be involved in transferring information between cortical areas. Although auditory corticothalamic pathways have been described in detail anatomically, their physiological properties are less well understood. Stimulation or deactivation of these cortical projections can alter the way MGB neurons respond to sound, effects that are mediated through a combination of their direct excitatory inputs and disynaptic inhibition via the thalamic reticular nucleus. It seems likely that corticothalamic modulation allows the sensitivity and selectivity of thalamocortical neurons in the MGB to be dynamically updated, shaping their responses depending on the behavioral and sensory context in which particular sounds are heard. The availability of methods for targeting specific populations of projection neurons during behavior is starting to reveal the crucial role these descending circuits play in auditory learning, active listening, and in the way the brain adjusts to the degraded inputs associated with hearing loss.