The Ultrasound Hepato-Jugular Reflux: Measuring the Hepato-Jugular Reflux with Ultrasound with Comparison to Invasive Right Heart Catheterization

BACKGROUND

Ultrasound can overcome barriers to visualizing the internal jugular vein, allowing hepato-jugular reflux and jugular venous pressure measurement. We aimed to determine operating characteristics of the ultrasound hepato-jugular reflux and ultrasound jugular venous pressure predicting right atrial and pulmonary capillary occlusion pressures.

METHODS

In a prospective observational cohort at three US academic hospitals the hepato-jugular reflux and jugular venous pressure were measured with ultrasound before right heart catheterization. Receiver operating curves, likelihood ratios, and regression models were utilized to compare the ultrasound hepato-jugular reflux and ultrasound jugular venous pressure to the right atrial and pulmonary capillary occlusion pressures.

RESULTS

In 99 adults undergoing right heart catheterization, an ultrasound hepato-jugular reflux had a negative likelihood ratio of 0.4 if 0 cm and a positive likelihood ratio of 4.3 if ≥ 1.5 cm for predicting a pulmonary capillary occlusion pressure ≥ 15 mmHg. Regression modeling predicting pulmonary capillary occlusion pressure was not only improved by including the ultrasound hepato-jugular reflux (P < .001), it was the more impactful predictor compared with the ultrasound jugular venous pressure (adjusted odds ratio 2.6 vs 1.2). The ultrasound hepato-jugular reflux showed substantial agreement (kappa 0.76; 95% confidence interval, 0.30-1.21), with poor agreement for the ultrasound jugular venous pressure (kappa 0.11; 95% confidence interval, -0.37-0.58).

CONCLUSION

In patients undergoing right heart catheterization, the ultrasound hepato-jugular reflux is reproducible, has modest impact on the probability of a normal pulmonary capillary occlusion pressure when 0 cm, and more substantial impact on the probability of an elevated pulmonary capillary occlusion pressure when ≥ 1.5 cm.

Lung ultrasound: A comparison of image interpretation accuracy between curvilinear and phased array transducers

Introduction

Both curvilinear and phased array transducers are commonly used to perform lung ultrasound (LUS). This study seeks to compare LUS interpretation accuracy of images obtained using a curvilinear transducer with those obtained using a phased array transducer.

Methods

We invited 166 internists and trainees to interpret 16 LUS images/cineloops of eight patients in an online survey: eight curvilinear and eight phased array, performed on the same lung location. Images depicted normal lung, pneumothorax, pleural irregularities, consolidation/hepatisation, pleural effusions and B-lines. Primary outcome for each participant is the difference in image interpretation accuracy scores between the two transducers.

Results

A total of 112 (67%) participants completed the survey. The mean paired accuracy score difference between the curvilinear and phased array images was 3.0% (95% CI: 0.6 to 5.4%, P = 0.015). For novices, scores were higher on curvilinear images (mean difference: 5.4%, 95% CI: 0.9 to 9.9%, P = 0.020). For non-novices, there were no differences between the two transducers (mean difference: 1.4%, 95% CI: -1.1 to 3.9%, P = 0.263). For pleural-based findings, the mean of the paired differences between transducers was higher in the novice group (estimated mean difference-in-differences: 9.5%, 95% CI: 0.6 to 18.4%; P = 0.036). No difference in mean accuracies was noted between novices and non-novices for non-pleural-based pathologies (estimated mean difference-in-differences: 0.6%, 95% CI to 5.4-6.6%; P = 0.837).

Conclusions

Lung ultrasound images obtained using the curvilinear transducer are associated with higher interpretation accuracy than the phased array transducer. This is especially true for novices interpreting pleural-based pathologies.

Smartphone-Guided Self-prone Positioning vs Usual Care in Nonintubated Hospital Ward Patients With COVID-19: A Pragmatic Randomized Clinical Trial

BACKGROUND

Safe, effective, and easily implementable treatments that reduce the progression of respiratory failure in COVID-19 are urgently needed. Despite the increased adoption of prone positioning during the pandemic, the effectiveness of this technique on progression of respiratory failure among nonintubated patients is unclear.

RESEARCH QUESTION

What is the effectiveness of smartphone-guided self-prone positioning recommendations and instructions compared with usual care in reducing progression of respiratory failure among nonintubated patients with COVID-19?

STUDY DESIGN AND METHODS

Awake Prone Position for Early Hypoxemia in COVID-19 (APPEX-19) is a multicenter randomized clinical trial that randomized nonintubated adults with COVID-19 on < 6 L/min of supplemental oxygen to receive a smartphone-guided self-prone positioning intervention or usual care. The primary outcome was the composite of respiratory deterioration (an increase in supplemental oxygen requirement) or ICU transfer. Using a Bayesian statistical approach, the posterior probability of superiority within each treatment arm (superiority threshold 95%) was calculated.

RESULTS

The trial was stopped early for slow enrollment. A total of 293 participants were included in the modified intention-to-treat analysis (159 self-prone positioning intervention and 134 usual care). Among participants who self-reported body positioning (n = 139 [70 intervention, 69 usual care]), 71.4% in the intervention arm and 59.4% in the usual care arm attempted prone positioning. Thirty-one participants (posterior mean, 24.7%; 95% credible interval, 18.6-31.4) receiving usual care and 32 participants (posterior mean, 22.1%; 95% credible interval, 16.6-28.1) receiving the self-prone positioning intervention experienced the primary outcome; the posterior probability of superiority for the self-prone positioning intervention was 72.1%, less than the 95% threshold for superiority. Adverse events occurred in 26.9% of participants in the usual care arm and in 11.9% of participants in the intervention arm.

INTERPRETATION

Among nonintubated patients with COVID-19, smartphone-guided self-prone positioning recommendations and instructions did not promote strong adherence to prone positioning.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov; No.: NCT04344587; URL: www.

CLINICALTRIALS

gov.

Lung Ultrasound for Pleural Line Abnormalities, Confluent B-Lines, and Consolidation: Expert Reproducibility and a Method of Standardization

OBJECTIVES

Discrete B-lines have clear definitions, but confluent B-lines, consolidations, and pleural line abnormalities are less well defined. We proposed definitions for these and determined their reproducibility using COVID-19 patient images obtained with phased array probes.

METHODS

Two raters collaborated to refine definitions, analyzing disagreements on 107 derivation scans from 10 patients. Refined definitions were used by those raters and an independent rater on 1260 validation scans from 105 patients. Reliability was evaluated using intraclass correlation coefficients (ICC) or Cohen's kappa.

RESULTS

The agreement was excellent between collaborating raters for B-line abnormalities, ICC = 0.97 (95% confidence interval [CI] 0.97-0.98) and pleural line to consolidation abnormalities, ICC = 0.90 (95% CI 0.87-0.92). The independent rater's agreement for B-line abnormalities was excellent, ICC = 0.97 (95% CI 0.96-0.97) and for pleural line to consolidation was good, ICC = 0.88 (95% CI 0.84-0.91). Agreement just on pleural line abnormalities was weak (collaborators, κ = 0.54, 95% CI 0.48-0.60; independent, κ = 0.54, 95% CI 0.49-0.59).

CONCLUSION

With proposed definitions or via collaboration, overall agreement on confluent B-lines and pleural line to consolidation abnormalities was robust. Pleural line abnormality agreement itself was persistently weak and caution should be used interpreting pleural line abnormalities with only a phased array probe.

POCUS Finding of Portal Venous Gas: An Unusual Consequence of an Amyloid Dysmotility Related Bezoar

A 73-year-old male with a recent finding of pericardial effusion and syncope was evaluated with point of care ultrasound for recurrent effusion. A thickened left ventricle and recurrent pericardial effusion were found. Unexpectedly, on scanning the inferior vena cava (IVC), extensive portal venous gas was identified, a finding previously described as a "meteor shower". Subsequent imaging by computed tomography (CT) identified gastric edema and peri-gastric vessel gas as the source of the portal gas, attributed to a large bezoar. The bezoar was later classified as a phytobezoar and the patient was found to have both cardiac and gastrointestinal manifestations of light chain amyloidosis. The gastrointestinal amyloidosis predisposed the patient to bezoar formation owing to associated dysmotility, a rare complication of an unusual manifestation of systemic amyloid.

Point-of-Care Lung Ultrasound for COVID-19: Findings and Prognostic Implications From 105 Consecutive Patients

Background:

The prognostic value of point-of-care lung ultrasound has not been evaluated in a large cohort of patients with COVID-19 admitted to general medicine ward in the United States. The aim of this study was to describe lung ultrasound findings and their prognostic value in patients with COVID-19 admitted to internal medicine ward.

Method:

This prospective observational study consecutively enrolled 105 hospitalized participants with COVID-19 at 2 tertiary care centers. Ultrasound was performed in 12 lung zones within 24 hours of admission. Findings were assessed relative to 4 outcomes: intensive care unit (ICU) need, need for intensive respiratory support, length of stay, and death.

Results:

We detected abnormalities in 92% (97/105) of participants. The common findings were confluent B-lines (92%), non-homogenous pleural lines (78%), and consolidations (54%). Large confluent B-lines, consolidations, bilateral involvement, and any abnormality in ≥ 6 areas were associated with a longer hospitalization and need for intensive respiratory support. Large confluent B-lines and bilateral involvement were also associated with ICU stay. A total lung ultrasound score <5 had a negative predictive value of 100% for the need of intensive respiratory support. A higher total lung ultrasound score was associated with ICU need (median total 18 in the ICU group vs. 11 non-ICU, p = 0.004), a hospitalization ≥ 9d (15 vs 10, p = 0.016) and need for intensive respiratory support (18 vs. 8.5, P < 0.001).

Conclusions:

Most patients hospitalized with COVID-19 had lung ultrasound abnormalities on admission and a higher lung ultrasound score was associated with worse clinical outcomes except death. A low total lung ultrasound score (<5) had a negative predictive value of 100% for the need of intensive respiratory support. Point-of-care ultrasound can aid in the risk stratification for patients with COVID-19 admitted to general wards.

Three-Dimensional Printed Cardiac Models for Focused Cardiac Ultrasound Instruction

BACKGROUND

Focused cardiac ultrasonography (FCU) is an increasingly integral component of routine medical training and practice. While various instructional methods have been described, few attempts have been made to incorporate a physical 3-dimensional (3D) instructional aid.

OBJECTIVE

The aim of this study was to determine if a 3D printed heart model workshop for FCU instruction leads to equivalent structure recognition and scanning ability compared to traditional didactic FCU instruction.

INTERVENTION

Twenty first-year medical students with no point-of-care ultrasonography experience were randomly assigned to a traditional lecture (n = 10) or a 3D printed heart model workshop (n = 10). Written examinations at 0 and 3 months as well as image acquisition at 3 months were compared.

RESULTS

The median scores from the initial written structure identification in the traditional and 3D heart groups were 74% and 90%, respectively (P = 0.7). The second written exam at 3 months yielded median scores of 56% and 58% in the traditional and 3D heart groups, respectively (P = 0.8). The average scores on the image acquisition practical at 3 months were 3.3 of 5 and 2.7 of 5 (P = 0.1) in the traditional and 3D heart groups, respectively.

CONCLUSIONS

Utilizing 3D heart models in an FCU workshop format results in similar skill acquisition and knowledge retention as traditional didactics. The 3D heart models are relatively inexpensive, portable, and reusable, enabling learners to practice repeatedly and at flexible intervals. The reduction in ongoing expenses and the ability to teach large groups may decrease training costs as well as the need for local faculty expertise.

Bayesian networks of BI-RADStrade mark descriptors for breast lesion classification

We investigated Bayesian network structure learning and probability estimation from mammographic feature data in order to classify breast lesions into different pathological categories. We compared the learned networks to naive Bayes classifiers, which are similar to the expert systems previously investigated for breast lesion classification. The learned network structures reflect the difference in the classification of biopsy outcome and the invasiveness of malignant lesions for breast masses and microcalcifications. The difference between masses and microcalcifications should be taken into consideration when interpreting systems for automatic pathological classification of breast lesions. The difference may also affect use of these systems for tasks such as estimating the sampling error of biopsy.

Empirical comparison of tests for differential expression on time-series microarray experiments

Methods for identifying differentially expressed genes were compared on time-series microarray data simulated from artificial gene networks. Select methods were further analyzed on existing immune response data of Boldrick et al. (2002, Proc. Natl. Acad. Sci. USA 99, 972-977). Based on the simulations, we recommend the ANOVA variants of Cui and Churchill. Efron and Tibshirani's empirical Bayes Wilcoxon rank sum test is recommended when the background cannot be effectively corrected. Our proposed GSVD-based differential expression method was shown to detect subtle changes. ANOVA combined with GSVD was consistent on background-normalized simulation data. GSVD with empirical Bayes was consistent without background correction. Based on the Boldrick et al. data, ANOVA is best suited to detect changes in temporal data, while GSVD and empirical Bayes effectively detect individual spikes or overall shifts, respectively. For methods tested on simulation data, lowess after background correction improved results. On simulation data without background correction, lowess decreased performance compared to median centering.

Empirical comparison of tests for differential expression on simulated time series microarray experiments

Methods for identifying differential expression were compared on time series microarray data from artificial gene networks. Identifying differential expression was dependent on normalization and whether the background was removed. Loess after background correction improved results for most methods. On data without background correction median centering improved performance. We recommend Cui and Churchill's ANOVA variants on background subtracted data and Efron and Tibshirani's Empirical Bayes Wilcoxon Rank Sum test when the background cannot be removed.

Integrated health care: passing fad or lasting legacy?

The breakup of several integrated delivery systems (IDSs), and a continuing focus on the failures of many of these organizations to live up to expectations, suggests that integration may be a passing trend. Nonetheless, some systems, particularly those driven by multispecialty clinics, are achieving considerable marketplace success. Integrated systems that base their strategies on delivering value-added services to patients and healthcare purchasers still appear viable. Strategies typically used by IDSs include developing primary care networks, gainsharing with or owning health plans, reducing clinical variation, demonstrating high quality, cutting costs, and developing a seamless system of care. Primary care strategies are especially controversial given the fact that most hospital-affiliated primary care practices are losing money. However, research indicates that primary network development is one of the strategies that adds the most value for consumers and, thus, may be assumed to be of particular benefit to IDSs. Strategies aimed at reducing clinical variation can be expected to reap huge long-term benefits.

Physician leaders in integrated delivery

It's common to hear the analogy comparing organizing physicians to "herding cats." Actual practice proves the adage false. Physicians are taking leadership roles in the formation of integrated systems across the country. Their input is proving invaluable. Based on case studies of integrated systems, the authors answer commonly asked questions about physician leaders, including: Should physician leaders be specilists? Should they continue to practice? and What will expensive physicians do to our administrative overhead?

Optimizing primary care services

One of the most recent and pervasive trends in healthcare is the restructuring of primary care. In many markets, the solo family practice physicians increasingly family practice physician is a thing of the past. Primary care physicians increasingly are aligning themselves with larger players such as multispecialty groups, hospitals, health plans, or practice management companies. This article draws on the authors' research into 20 healthcare systems in various stages of development as well as their own consulting experience to answer several questions: Why is the establishment or purchase of primary care physician practices an exploding national trend? What are the pros and cons of this approach? Is it better to purchase existing practices or establish new ones from the ground up? What are the pros and cons of virtual integration (affiliation without purchase) versus other forms of integration?

Making integrated health care work

This article summarizes the authors' thinking on value added in health care, and offers examples of the major strategies being implemented by integrated systems across the United States to increase their value and improve their competitive positioning. The research results are based on a review of published literature on 150 health care organizations in various stages of integration, and 20 in-depth case studies of integrating systems.

Making integrated health care work

The primary purpose of forming integrated health care systems should be to increase value added for payers and patients. Without this kind of focus on customer needs, integration efforts are likely to fail. The authors identify seven factors that make up the value-added continuum for health care purchasers and providers. The article assesses several of the major strategies pursued by integrating systems (e.g., primary care network development, health plan partnership arrangements) against value-added criteria. The major finding: integrated health care has the potential to bring substantial added value to customers.

Costs and benefits of integrated healthcare systems

Although forming an integrated healthcare system can be extremely expensive, many hospitals and physician groups are discovering that by doing so, they can reap significant benefits, including increased market share, more secure physician income, and better physician "quality of life," a financially stronger organization, and an enhanced ability to adapt to the changing healthcare environment. In most cases, the return on the investment required to reorganize the physician, hospital, and healthcare plan relationship is likely to be substantial.

Integrated health care systems: the key characteristics

Cooperation among the traditionally adversarial factions of physicians and hospitals has arisen in the early 1990s to develop the integrated health care system. Authors Dean C. Coddington, Keith D. Moore and Elizabeth A. Fischer explain how these two groups have been joined in the integration by an unlikely participant: health plans.

Covalent binding of detergent-solubilized membrane glycoproteins to 'Chemobond' plates for ELISA

An ELISA method is presented which is based on covalent binding of detergent-solubilized membrane proteins to surface-modified polystyrene plates (Chemobond plates). These plates carried 0.52-0.65 nmol of aldehyde groups per well (150 microliters) and allowed coupling of protein by Schiff base formation either at high pH and subsequent reduction with NaBH4 or by trapping reduced imines at pH 6-6.8 with cyanoborohydride. They bound 15 times the amount of normal plates. Sodium chloride (0.5 M) increased binding 2-3-fold. Binding was essentially resistant to elution by 1% sodium dodecyl sulfate. Reduction of uncoated plates with NaBH4 eliminated the high extent of binding. ELISA tests on Chemobond plates with a rabbit anti-band 3 antibody gave a ten-fold higher signal than plates to which band 3 protein was merely adsorbed. The use of an antigen-enzyme conjugate to detect bound antibody allowed to perform antibody binding and detection of bound antibody simultaneously in the presence of 0.05% Triton X-100. A competitive, one step ELISA system allowed determination of rabbit anti-band 3 antibodies in diluted serum with a sensitivity range of 0.02-0.4 microgram/ml.

The detection of antibodies to recombinant interferon alfa-2a in human serum

Three different procedures have been used for detecting antibodies to Roferon-A (recombinant human interferon alfa-2a, rHuIFN alpha-2a) in the serum of patients who received this interferon as part of ongoing clinical trials: an antiviral neutralization bioassay (ANB), the standard method recommended by the World Health Organization (WHO), and the more recently developed radioimmunoassay (RIA) and enzymeimmunoassay (EIA). Although the three tests are based on different principles, the correlation among them was excellent. The assays show differences in sensitivities with the ANB being the least sensitive of the three. The EIA equals the RIA in sensitivity, reproducibility, accuracy and labor and provides the advantage of safety and convenience in the use of non-radioactive materials. Therefore, the EIA has been selected as the most suitable assay for initial screening of the sera of patients receiving Roferon-A for the presence of antibodies to this interferon. EIA positive sera are then tested in the ANB to determine whether or not neutralizing activities are present.