Associations of Fatty Liver Disease With Recovery After Traumatic Injury.

INTRODUCTION: Fatty liver disease (FLD) is associated with systemic inflammation, metabolic disease, and socioeconomic risk factors for poor health outcomes. Little is known on how adults with FLD recover from traumatic injury. METHODS: We studied adults admitted to the intensive care unit of a level 1 trauma center (2016-2020), excluding severe head injury/cirrhosis (N = 510). We measured the liver-spleen attenuation difference in Hounsfield units (HUL-S) using virtual noncontrast computerized tomography scans: none (HUL-S>1), mild (-10≤HUL-S<1), moderate/severe (HUL-S < -10). We used Cox models to examine the "hazard" of recovery from systemic inflammatory response (SIRS score 2 or higher) organ dysfunction, defined as sequential organ failure assessment score 2 or higher, and lactate clearance (<2 mmol/L) in relation to FLD. RESULTS: Fifty-one participants had mild and 29 had moderate/severe FLD. The association of FLD with recovery from SIRS differed according to whether an individual had shock on admission (hazard ratio [HR] = 0.76; 95% confidence interval [CI] 0.55-1.05 with shock; HR = 1.81; 95% CI 1.43-2.28 without shock). Compared to patients with no FLD, the hazard of lactate clearance was similar for mild FLD (HR = 1.04; 95% CI 0.63-1.70) and lower for moderate/severe FLD (HR = 0.40; 95% CI 0.18-0.89). CONCLUSIONS: FLD is common among injured adults. Associations of FLD with outcomes after shock and critical illness warrant further study.

Outcomes of Patients with COVID-19 from a Specialized Cancer Care Emergency Room.

PURPOSE: Our goal was to identify discrete clinical characteristics associated with safe discharge from an emergency department/urgent care for patients with a history of cancer and concurrent COVID-19 infection during the SARS-CoV-2 pandemic and prior to widespread vaccination. PATIENTS AND METHODS: We retrospectively analyzed 255 adult patients with a history of cancer who presented to Memorial Sloan Kettering Cancer Center (MSKCC) urgent care center (UCC) from March 1, 2020 to May 31, 2020 with concurrent COVID-19 infection. We evaluated associations between patient characteristics and 30-day mortality from initial emergency department (ED) or urgent care center (UCC) visit and the absence of a severe event within 30 days. External validation was performed on a retrospective data from 29 patients followed at Fred Hutchinson Cancer Research Center that presented to the local emergency department. A late cohort of 108 additional patients at MSKCC from June 1, 2020 to January 31, 2021 was utilized for further validation. RESULTS: In the MSKCC cohort, 30-day mortality and severe event rate was 15% and 32% respectively. Using stepwise regression analysis, elevated BUN and glucose, anemia, and tachypnea were selected as the main predictors of 30-day mortality. Conversely, normal albumin, BUN, calcium, and glucose, neutrophil-lymphocyte ratio <3, lack of (severe) hypoxia, lack of bradycardia or tachypnea, and negative imaging were selected as the main predictors of an uneventful course as defined as a Lack Of a Severe Event within Thirty Days (LOSETD). Utilizing this information, we devised a tool to predict 30-day mortality and LOSETD which achieved an area under the operating curve (AUC) of 79% and 74% respectively. Similar estimates of AUC were obtained in an external validation cohort. A late cohort at MSKCC was consistent with the prior, albeit with a lower AUC. CONCLUSION: We identified easily obtainable variables that predict 30-day mortality and the absence of a severe event for patients with a history of cancer and concurrent COVID-19. This has been translated into a bedside tool that the clinician may utilize to assist disposition of this group of patients from the emergency department or urgent care setting.

Airspace dimension assessment with nanoparticles as a proposed biomarker for emphysema.

Airspace dimension assessment with nanoparticles (AiDA) is a novel method to measure distal airspace radius non-invasively. In this study, AiDA radii were measured in 618 individuals from the population-based Swedish CArdiopulmonary BioImaging Study, SCAPIS. Subjects with emphysema detected by computed tomography were compared to non-emphysematous subjects. The 47 individuals with mainly mild-to-moderate visually detected emphysema had significantly larger AiDA radii, compared with non-emphysematous subjects (326±48 µm vs 291±36 µm); OR for emphysema per 10 µm: 1.22 (1.13-1.30, p<0.0001). Emphysema according to CT densitometry was similarly associated with larger radii compared with non-emphysematous CT examinations (316±41 µm vs 291 µm±26 µm); OR per 10 µm: 1.16 (1.08-1.24, p<0.0001). The results are in line with comparable studies. The results show that AiDA is a potential biomarker for emphysema in individuals in the general population.

Core curriculum case illustration: cardiac tamponade complicating proximal aortic dissection.

This is the 39th installment of a series that will highlight one case per publication issue from the bank of cases available online as part of the American Society of Emergency Radiology (ASER) educational resources. Our goal is to generate more interest in and use of our online materials. To view more cases online, please visit the ASER Core Curriculum and Recommendations for Study online at http://www.erad.org/page/CCIP_TOC .

Altered deposition of inhaled nanoparticles in subjects with chronic obstructive pulmonary disease.

BACKGROUND: Respiratory tract deposition of airborne particles is a key link to understand their health impact. Experimental data are limited for vulnerable groups such as individuals with respiratory diseases. The aim of this study is to investigate the differences in lung deposition of nanoparticles in the distal lung for healthy subjects and subjects with respiratory disease. METHODS: Lung deposition of nanoparticles (50 and 100 nm) was measured after a 10 s breath-hold for three groups: healthy never-smoking subjects (n = 17), asymptomatic (active and former) smokers (n = 15) and subjects with chronic obstructive pulmonary disease (n = 16). Measurements were made at 1300 mL and 1800 mL volumetric lung depth. Each subject also underwent conventional lung function tests, including post bronchodilator FEV1, VC, and diffusing capacity for carbon monoxide, DL,CO. Patients with previously diagnosed respiratory disease underwent a CT-scan of the lungs. Particle lung deposition fraction, was compared between the groups and with conventional lung function tests. RESULTS: We found that the deposition fraction was significantly lower for subjects with emphysema compared to the other subjects (p = 0.001-0.01), but no significant differences were found between healthy never-smokers and smokers. Furthermore, the particle deposition correlated with pulmonary function tests, FEV1%Pred (p < 0.05), FEV1/VC%Pred (p < 0.01) and DL,CO (p < 0.0005) when all subjects were included. Furthermore, for subjects with emphysema, deposition fraction correlated strongly with DL,CO (Pearson's r = 0.80-0.85, p < 0.002) while this correlation was not found within the other groups. CONCLUSIONS: Lower deposition fraction was observed for emphysematous subjects and this can be explained by enlarged distal airspaces in the lungs. As expected, deposition increases for smaller particles and deeper inhalation. The observed results have implications for exposure assessment of air pollution and dosimetry of aerosol-based drug delivery of nanoparticles.

Airspace Dimension Assessment with Nanoparticles (AiDA) in Comparison to Established Pulmonary Function Tests.

Background: Airspace Dimensions Assessment with nanoparticles (AiDA) is a new method for non-invasive measurement of pulmonary distal airspaces. The aim of this study was to compare AiDA measurements with other pulmonary function variables to better understand the potential of AiDA in a clinical context. Methods: AiDA measurements and pulmonary function tests were performed in 695 subjects as part of the Swedish CArdioPulmonary bioImage Study. The measurement protocol included spirometry, measurement of diffusing capacity of carbon monoxide, oscillometry and pulmonary computed tomography. AiDA indices were compared to all other pulmonary examination measurements using multivariate statistical analysis. Results: Our results show that AiDA measurements were significantly correlated with other pulmonary function examination indices, although covariance was low. We found that AiDA variables explained variance in the data that other lung function variables only influenced to a minor extent. Conclusion: We conclude that the AiDA method provides information about the lung that is inaccessible with more conventional lung function techniques.

Sources of error in bone mineral density estimates from quantitative CT.

Bone mineral density (BMD) estimates from quantitative computed tomography (QCT) have proven useful for opportunistic screening of osteoporosis, treatment monitoring, and bone strength measurement. These estimates are subject to bias and variance from a variety of sources related to the imaging equipment, methods applied in the estimation procedure, and the patients themselves. In this article, we review the literature to describe the sources and sizes of error in spine and hip BMD estimates from single-energy QCT that can result from factors related to the scanner, imaging techniques, imaging subject, calibration phantom, and calibration approach. We also describe the baseline variance that can be expected based on repeatability and reproducibility studies. Though reproducible BMD estimates may be achievable with QCT, a thorough understanding of the potential sources of error and their size relative to the diagnostic task is essential to their appropriate and meaningful interpretation.

Mixed Airway and Pulmonary Parenchymal Disease in Patients With Primary Sjögren Syndrome: A 6-year Follow-up.

OBJECTIVE: To assess pulmonary function and chronic obstructive pulmonary disease (COPD) development over time in patients with primary Sjögren syndrome (pSS), as well as the association between pulmonary function, radiographic findings, respiratory symptoms, and clinical features of pSS, taking cigarette consumption into account. METHODS: Forty patients with pSS (mean age 66 yrs; range 42-81 yrs; 39 women), previously participating in a cross-sectional study on pulmonary involvement in pSS, were reassessed by pulmonary function tests after a mean follow-up time of 6 years. At follow-up, patients were also assessed by high-resolution computed tomography of the chest, as well as for pSS disease activity, respiratory symptoms, and cigarette consumption. RESULTS: Patients with pSS showed significantly decreased percentages of predicted total lung capacity (TLC), residual volume (RV), RV/TLC ratio, and diffusing capacity of the lungs for carbon monoxide, as well as an increase in predicted forced expiratory volume in 1 second/vital capacity (FEV1/VC) ratio from baseline to follow-up. The proportion of COPD in patients with pSS did not change significantly from baseline to follow-up (38% vs 40%, respectively). Radiographic signs of bronchial involvement and interstitial lung disease were each found in 38% of the patients. CONCLUSION: Both airway and pulmonary parenchymal disease were commonly found in patients with pSS, with a coexistence of both an obstructive and restrictive pulmonary function pattern, where the latter tended to deteriorate over time. COPD was a common finding. Airway and pulmonary involvement may be underdiagnosed in pSS, which is why special attention to clinical assessment of pulmonary involvement in patients with pSS is mandated.

A significant correlation between body surface area and infrarenal aortic diameter is detected in a large screening population with possibly clinical implications.

BACKGROUND: Screening for abdominal aortic aneurysm (AAA) in elderly men reduces aneurysm related mortality. AAA is commonly defined as an infrarenal aortic diameter (IAD) of ≥30 mm, which is based on the definition of an arterial aneurysm as a focal dilation of 150% or more compared to the expected diameter of about 20 mm. The IAD has been shown to correlate to body surface area (BSA). The aim of this study was to investigate the possibility to use an individualized AAA-criteria by using a BSA-based model to refine the screening for AAA. METHODS: We conducted an observational single center cohort study of 25 236 65-year old men invited to AAA screening in Malmö, Sweden 2010-2015. Out of the 19 738 (78.5%) attendees, 14 846 (58.8%) completed a health questionnaire including height, weight and smoking habits. Linear regression analysis was performed between BSA and IAD, taking smoking habits into account. This regression was used to calculate the predicted IAD for each individual according to their BSA. RESULTS: There was a significant correlation between BSA and aortic diameter, rho =0.26 (95% CI: 0.25, 0.28). AAA defined as an IAD≥30 mm was found in 226 men (1.5%) whereas AAA defined as ≥150% larger IAD than predicted according to the individual BSA was found in 299 men (1.9%), a relative difference in AAA detection rate of more than 30% (P<0.001). CONCLUSIONS: We have found a statistically significant correlation between BSA and IAD in a homogenous screening population that could have clinical implications. In men with low BSA, IAD <30 mm might still be ≥150% larger than predicted according to BSA, whereas in men with high BSA, IAD≥30 mm might not be ≥150% larger than predicted. Further follow-up of these subjects is planned to investigate if the first group have an "aneurysm-in-formation," challenging the diagnostic criteria for AAA.

Airspace Dimension Assessment with nanoparticles reflects lung density as quantified by MRI.

BACKGROUND: Airspace Dimension Assessment with inhaled nanoparticles is a novel method to determine distal airway morphology. This is the first empirical study using Airspace Dimension Assessment with nanoparticles (AiDA) to estimate distal airspace radius. The technology is relatively simple and potentially accessible in clinical outpatient settings. METHOD: Nineteen never-smoking volunteers performed nanoparticle inhalation tests at multiple breath-hold times, and the difference in nanoparticle concentration of inhaled and exhaled gas was measured. An exponential decay curve was fitted to the concentration of recovered nanoparticles, and airspace dimensions were assessed from the half-life of the decay. Pulmonary tissue density was measured using magnetic resonance imaging (MRI). RESULTS: The distal airspace radius measured by AiDA correlated with lung tissue density as measured by MRI (ρ = -0.584; p = 0.0086). The linear intercept of the logarithm of the exponential decay curve correlated with forced expiratory volume in one second (FEV1) (ρ = 0.549; p = 0.0149). CONCLUSION: The AiDA method shows potential to be developed into a tool to assess conditions involving changes in distal airways, eg, emphysema. The intercept may reflect airway properties; this finding should be further investigated.

Do nanoparticles provide a new opportunity for diagnosis of distal airspace disease?

There is a need for efficient techniques to assess abnormalities in the peripheral regions of the lungs, for example, for diagnosis of pulmonary emphysema. Considerable scientific efforts have been directed toward measuring lung morphology by studying recovery of inhaled micron-sized aerosol particles (0.4-1.5 µm). In contrast, it is suggested that the recovery of inhaled airborne nanoparticles may be more useful for diagnosis. The objective of this work is to provide a theoretical background for the use of nanoparticles in measuring lung morphology and to assess their applicability based on a review of the literature. Using nanoparticles for studying distal airspace dimensions is shown to have several advantages over other aerosol-based methods. 1) Nanoparticles deposit almost exclusively by diffusion, which allows a simpler breathing maneuver with minor artifacts from particle losses in the oropharyngeal and upper airways. 2) A higher breathing flow rate can be utilized, making it possible to rapidly inhale from residual volume to total lung capacity (TLC), thereby eliminating the need to determine the TLC before measurement. 3) Recent studies indicate better penetration of nanoparticles than micron-sized particles into poorly ventilated and diseased regions of the lungs; thus, a stronger signal from the abnormal parts is expected. 4) Changes in airspace dimensions have a larger impact on the recovery of nanoparticles. Compared to current diagnostic techniques with high specificity for morphometric changes of the lungs, computed tomography and magnetic resonance imaging with hyperpolarized gases, an aerosol-based method is likely to be less time consuming, considerably cheaper, simpler to use, and easier to interpret (providing a single value rather than an image that has to be analyzed). Compared to diagnosis by carbon monoxide (DL,CO), the uptake of nanoparticles in the lung is not affected by blood flow, hemoglobin concentration or alterations of the alveolar membranes, but relies only on lung morphology.