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Purpose Central vein point-of-care ultrasonography must be reproducible to detect intravascular volume changes. We sought to determine which measurement step, image acquisition or interpretation, could be more compromising for reproducibility. Methods Three investigators each acquired inferior vena cava (IVC) and internal jugular (IJV) vein ultrasonographic sequences (US) from a convenience sample of 21 hospitalized general medicine participants and then interpreted each US three separate times. We partitioned the random errors of acquisition and interpretation, attributing wider dispersions of each to larger reductions in reproducibility. Results We analyzed 351 interpretations of 39 IVC and 432 interpretations of 48 IJV US. Reproducibility of the maximum (standard error of measurement 3.3 mm [95% confidence interval, CI 2.7–4.2 mm]) and minimum (4.8 mm [3.9–6.3 mm]) IVC diameter measurements were worse than that of the mediolateral (2.5 mm [2.0–3.2 mm]) and anteroposterior (2.5 mm [2.0–3.1 mm]) IJV diameters. The dispersions of random measurement errors were wider among acquisitions than interpretations. Conclusions Among our investigators, central vein diameter measurements obtained by point-of-care ultrasonography are not sufficiently reproducible to distinguish clinically meaningful intravascular volume changes from measurement errors. Reproducibility could be most effectively improved by reducing the random measurement errors of acquisition. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound, 2017

Background Current methods of assessing competence in acquiring point-of-care ultrasound images are inadequate. They rely upon cumbersome rating systems that do not depend on the actual outcome measured and lack evidence of validity. We describe a new method that uses a rigorous statistical model to assess performance of individual trainees based on the actual task, image acquisition. Measurements obtained from the images acquired (the actual desired outcome) are themselves used to validate effective training and competence acquiring ultrasound images. We enrolled a convenience sample of 21 spontaneously breathing adults from a general medicine ward. In random order, two trainees (A and B) and an instructor contemporaneously acquired point-of-care ultrasound images of the inferior vena cava and the right internal jugular vein from the same patients. Blinded diameter measurements from each ultrasound were analyzed quantitatively using a multilevel model. Consistent mean differences between each trainee’s and the instructor’s images were ascribed to systematic acquisition errors, indicative of poor measurement technique and a need for further training. Wider variances were attributed to sporadic errors, indicative of inconsistent application of measurement technique across patients. In addition, the instructor recorded qualitative observations of each trainee’s performance during image acquisition. Results For all four diameters, the means and variances of measurements from trainee A’s images differed significantly from the instructor’s, whereas those from trainee B’s images were comparable. Techniques directly observed by the instructor supported these model-derived findings. For example, mean anteroposterior diameters of the internal jugular vein obtained from trainee A’s images were 3.8 mm (90% CI 2.3–5.4) smaller than from the instructor’s; this model-derived finding matched the instructor’s observation that trainee A compressed the vein during acquisition. Instructor summative assessments agreed with model-derived findings, providing internal validation of the descriptive and quantitative assessments of competence acquiring ultrasound images. Conclusions Clinical measurements obtained from point-of-care ultrasound images acquired contemporaneously by trainees and an instructor can be used to quantitatively assess the image acquisition competence of specific trainees. This method may obviate resource-intensive qualitative rating systems that are based on ultrasound image quality and direct observation, while also helping instructors guide remediation. Electronic supplementary material The online version of this article (10.1186/s13089-019-0119-6) contains supplementary material, which is available to authorized users.

Central airway stenosis is extremely rare in pregnancy and could lead to respiratory and cardiovascular embarrassment, especially at the time of delivery. Initially, patients may not show obvious signs of respiratory difficulty. Early recognition of the disease and anticipatory management of a complicated delivery are very important. We present a pregnant patient with tuberculosis-induced severe tracheobronchial stenosis and discuss the management challenges of her delivery.

A direct relationship exists within subjects between midlatency features (

In 2009, the American Thoracic Society (ATS) funded an assembly project, Palliative Management of Dyspnea Crisis, to focus on identification, management, and optimal resource utilization for effective palliation of acute episodes of dyspnea. We conducted a comprehensive search of the medical literature and evaluated available evidence from systematic evidence-based reviews (SEBRs) using a modified AMSTAR approach and then summarized the palliative management knowledge base for participants to use in discourse at a 2009 ATS workshop. We used an informal consensus process to develop a working definition of this novel entity and established an Ad Hoc Committee on Palliative Management of Dyspnea Crisis to further develop an official ATS document on the topic. The Ad Hoc Committee members defined dyspnea crisis as "sustained and severe resting breathing discomfort that occurs in patients with advanced, often life-limiting illness and overwhelms the patient and caregivers' ability to achieve symptom relief." Dyspnea crisis can occur suddenly and is characteristically without a reversible etiology. The workshop participants focused on dyspnea crisis management for patients in whom the goals of care are focused on palliation and for whom endotracheal intubation and mechanical ventilation are not consistent with articulated preferences. However, approaches to dyspnea crisis may also be appropriate for patients electing life-sustaining treatment. The Ad Hoc Committee developed a Workshop Report concerning assessment of dyspnea crisis; ethical and professional considerations; efficient utilization, communication, and care coordination; clinical management of dyspnea crisis; development of patient education and provider aid products; and enhancing implementation with audit and quality improvement.

Dyspnea may be defined as an uncomfortable sensation of breathing. The sense of respiratory effort, chemoreceptor stimulation, mechanical stimuli arising in lung and chest wall receptors, and neuroventilatory dissociation may all contribute to the sensation of dyspnea. Different mechanisms likely give rise to qualitatively different sensations of dyspnea. In most patients, dyspnea is probably due to a combination of mechanisms. For example, in asthma, a heightened sense of effort, neuroventilatory dissociation, and vagal stimuli arising from bronchoconstriction and airway inflammation may all play a role. Patients with different disorders and different mechanisms of dyspnea use different phrases to describe their breathing discomfort. Hence, the language patients use to describe their dyspnea may provide clues to the etiology of their symptoms.

IMPLICATIONS We report a case of toxicity from the drug solvent propylene glycol resulting from prolonged, large-dose lorazepam infusion. The case is unusual in that toxicity developed during continuous veno-venous hemofiltration with dialysis, a renal replacement therapy that should been have been effective at eliminating the chemical and its metabolites.

Background This consensus statement was developed based on the understanding that patients with advanced lung or heart disease are not being treated consistently and effectively for relief of dyspnea. Methods A panel of experts was convened. After a literature review, the panel developed 23 statements covering five domains that were considered relevant to the topic condition. Endorsement of these statements was assessed by levels of agreement or disagreement on a five-point Likert scale using two rounds of the Delphi method. Results The panel defined the topic condition as "dyspnea that persists at rest or with minimal activity and is distressful despite optimal therapy of advanced lung or heart disease." The five domains were: measurement of patient-reported dyspnea, oxygen therapy, other therapies, opioid medications, and ethical issues. In the second round of the Delphi method, 34 of 56 individuals (61%) responded, and agreement of at least 70% was achieved for 20 of the 23 statements. Conclusions For patients with advanced lung or heart disease, we suggest that: health-care professionals are ethically obligated to treat dyspnea, patients should be asked to rate the intensity of their breathlessness as part of a comprehensive care plan, opioids should be dosed and titrated for relief of dyspnea in the individual patient, both the patient and clinician should reassess whether specific treatments are serving the goal of palliating dyspnea without causing adverse effects, and it is important for clinicians to communicate about palliative and end-of-life care with their patients.

Limited information is available about current practice patterns involving the use of antibiotics in the inpatient management of acute exacerbations of chronic obstructive pulmonary disease (AECOPD). We sought to characterize current patterns of antibiotic use and to compare them to evidence-based guidelines. This study is a retrospective case series of patients at a regional tertiary care medical center. Charts were reviewed to identify patients admitted between January 2006 and 2008 with an initial diagnosis of AECOPD who had no evidence of another infectious process and who were not immunocompromised. Relevant data extracted from charts included initial clinical presentation, antibiotic administration, microbiological studies, and hospital course. One hundred sixteen admissions meeting inclusion criteria were identified. There was no statistically significant relationship between the presence of an established indication for antibiotic administration and the use of antibiotics, with roughly 75% of patients in all groups receiving therapy. A significant fraction of patients received combination therapy that was more appropriate for the management of pneumonia than for AECOPD. There were significant deviations between practice patterns and guidelines regarding the use and selection of antibiotics. Some of these may reflect areas of uncertainty in the primary literature and varying sets of guidelines.

Instillation into the urinary tract of the bacillus Calmette-Guérin (BCG), a strain of Mycobacterium bovis, is associated only rarely with severe side effects. We report here two cases of culture-proven pulmonary infection due to therapy with BCG. The first patient, who was seropositive for the human immunodeficiency virus, developed bilateral interstitial pneumonitis after instillation of BCG into the bladder. The second patient developed a right-lower-lobe infiltrate and empyema after instillation of BCG into the right renal pelvis. The clinical isolates from these two patients and from a third patient with a psoas abscess following intravesical instillation were analyzed with use of pulsed field gel electrophoresis (PFGE) to resolve chromosomal restriction fragment polymorphisms. The clinical isolates were confirmed to be BCG by comparison with known vaccine strains that differed from M. bovis isolates. We conclude that the potential for subsequent dissemination be considered prior to the intravesical administration of BCG. Analysis with PFGE may be useful for identifying species of the Mycobacterium tuberculosis complex.

Dyspnea is a cardinal symptom of asthma and may arise from several pathophysiological mechanisms, including pulmonary hyperinflation, stimulation of vagal receptors, and, rarely, chemoreceptor stimulation. The language that patients use to describe their breathlessness may provide important clues about the physiology underlying symptoms in a particular patient. Several physiological derangements may contribute to dyspnea in a given individual. The variability in the severity of breathlessness for any given degree of airflow obstruction may relate to differences in the relative importance of these physiological changes and/or to a range of perceptual abilities in asthmatic patients. One hypothesis that is under current investigation is that defective perception of asthma symptoms may lead to undertreatment and the potential for greater morbidity and mortality from asthma.

Objective: To examine the phenomenon of inappropriate triggering caused by an in-line suction catheter. Design: We used a test lung to assess inappropriate triggering in four ventilators with both pressure and flow triggering. Results: With pressure triggering, inappropriate triggering occurred only in the presence of PEEP. However, with flow triggering, inappropriate triggering occurred both with and without PEEP. Inappropriate triggering did not occur in a model of severe airflow obstruction. Conclusion: In-line suction catheters may lead to inappropriate triggering and potentially dangerous increases in delivered ventilation.

This paper reviews new developments in bronchodilator therapy for chronic obstructive pulmonary disease (COPD). Most patients with COPD respond to bronchodilators, but we have no reliable way to predict which patients will respond. When responsiveness is assessed, changes in lung volume as well as improvements in FEV1 should be considered. The combination of a beta-agonist and an anticholinergic agent produces greater improvement than either agent alone. Anticholinergic agents have few adverse side effects in patients with COPD, but concern remains about the possible cardiac side effects of beta-agonists. No clear answer exists about whether new, long-acting beta-agonists, such as salmeterol, should supplant anticholinergic agents as "first-line" therapy in COPD.

We examined the effect of inspiratory flow rate (IFR) on respiratory sensation during mechanical ventilation in 10 normal subjects. We adjusted the ventilator tidal volume (VT), frequency, and IFR until subjects indicated that they were maximally comfortable ("comfort IFR"). Subjects then rated breathing discomfort on a visual analog scale (VAS) while IFR was varied among four levels: 70%, 100%, 200%, and 300% of the comfort IFR. When compared with VAS ratings at the comfort IFR (4.4 +/- 1.2, mean +/- SEM), VAS ratings were significantly greater at the lowest (i.e., 70% comfort; 12.1 +/- 2.1) and highest (300% comfort; 8.2 +/- 0.9) IFR; there was no difference in ratings between the comfort IFR and 200% comfort IFR. At the lowest IFR, the breathing discomfort arose in the chest and had an air hunger-like quality; at high IFR, the discomfort arose in the upper airway. In the second portion of the study, subjects used open magnitude estimation to rate breaths of five different sizes at three different IFR (70%, 100%, and 200% of comfort rate). Neither the exponent nor intercept for VT perception differed among the three IFR. Our results demonstrate that although IFR does not alter magnitude estimation of breath size, deviations of IFR from that desired by the subject may greatly affect respiratory comfort.

over the past 20-30 years, substantial progress has been made in our understanding of dyspnea. We have come to the realization that dyspnea encompasses a number of distinct sensations ([16][1]) and that a diverse array of receptors in the chest wall, lungs, airways, and central nervous system may

Severe ethylene glycol toxicity can cause profound morbidity and is almost universally fatal if untreated. Central nervous system depression with intoxication, pulmonary edema, and acute oliguric renal failure with crystalluria are among the most commonly encountered complications of ingestion. The previously reported gastrointestinal side effects of ethylene glycol toxicity are mostly nonspecific, including nausea, abdominal pain, and cramping. In addition, hepatic damage due to calcium oxalate deposition has been reported. We describe a patient who developed acute colonic ischemia following ethylene glycol intoxication. Three months after the ingestion, the patient presented with severe abdominal pain secondary to a colonic stricture and perforation, necessitating emergent colectomy. Histology of the resected colon revealed polarizable polyhedral crystals suggestive of oxalate deposition. The pathophysiology underlying ethylene glycol intoxication, treatment strategies, and gastrointestinal toxicity are discussed.