AI-dente: an open machine learning based tool to interpret nano-indentation data of soft tissues and materials.

Nano-indentation is a promising method to identify the constitutive parameters of soft materials, including soft tissues. Especially when materials are very small and heterogeneous, nano-indentation allows mechanical interrogation where traditional methods may fail. However, because nano-indentation does not yield a homogeneous deformation field, interpreting the resulting load-displacement curves is non-trivial and most investigators resort to simplified approaches based on the Hertzian solution. Unfortunately, for small samples and large indentation depths, these solutions are inaccurate. We set out to use machine learning to provide an alternative strategy. We first used the finite element method to create a large synthetic data set. We then used these data to train neural networks to inversely identify material parameters from load-displacement curves. To this end, we took two different approaches. First, we learned the indentation forward problem, which we then applied within an iterative framework to identify material parameters. Second, we learned the inverse problem of directly identifying material parameters. We show that both approaches are effective at identifying the parameters of the neo-Hookean and Gent models. Specifically, when applied to synthetic data, our approaches are accurate even for small sample sizes and at deep indentation. Additionally, our approaches are fast, especially compared to the inverse finite element approach. Finally, our approaches worked on unseen experimental data from thin mouse brain samples. Here, our approaches proved robust to experimental noise across over 1000 samples. By providing open access to our data and code, we hope to support others that conduct nano-indentation on soft materials.

Development and Validation of a Respiratory-Responsive Vocal Biomarker-Based Tool for Generalizable Detection of Respiratory Impairment: Independent Case-Control Studies in Multiple Respiratory Conditions Including Asthma, Chronic Obstructive Pulmonary Disease, and COVID-19.

BACKGROUND: Vocal biomarker-based machine learning approaches have shown promising results in the detection of various health conditions, including respiratory diseases, such as asthma. OBJECTIVE: This study aimed to determine whether a respiratory-responsive vocal biomarker (RRVB) model platform initially trained on an asthma and healthy volunteer (HV) data set can differentiate patients with active COVID-19 infection from asymptomatic HVs by assessing its sensitivity, specificity, and odds ratio (OR). METHODS: A logistic regression model using a weighted sum of voice acoustic features was previously trained and validated on a data set of approximately 1700 patients with a confirmed asthma diagnosis and a similar number of healthy controls. The same model has shown generalizability to patients with chronic obstructive pulmonary disease, interstitial lung disease, and cough. In this study, 497 participants (female: n=268, 53.9%; <65 years old: n=467, 94%; Marathi speakers: n=253, 50.9%; English speakers: n=223, 44.9%; Spanish speakers: n=25, 5%) were enrolled across 4 clinical sites in the United States and India and provided voice samples and symptom reports on their personal smartphones. The participants included patients who are symptomatic COVID-19 positive and negative as well as asymptomatic HVs. The RRVB model performance was assessed by comparing it with the clinical diagnosis of COVID-19 confirmed by reverse transcriptase-polymerase chain reaction. RESULTS: The ability of the RRVB model to differentiate patients with respiratory conditions from healthy controls was previously demonstrated on validation data in asthma, chronic obstructive pulmonary disease, interstitial lung disease, and cough, with ORs of 4.3, 9.1, 3.1, and 3.9, respectively. The same RRVB model in this study in COVID-19 performed with a sensitivity of 73.2%, specificity of 62.9%, and OR of 4.64 (P<.001). Patients who experienced respiratory symptoms were detected more frequently than those who did not experience respiratory symptoms and completely asymptomatic patients (sensitivity: 78.4% vs 67.4% vs 68%, respectively). CONCLUSIONS: The RRVB model has shown good generalizability across respiratory conditions, geographies, and languages. Results using data set of patients with COVID-19 demonstrate its meaningful potential to serve as a prescreening tool for identifying individuals at risk for COVID-19 infection in combination with temperature and symptom reports. Although not a COVID-19 test, these results suggest that the RRVB model can encourage targeted testing. Moreover, the generalizability of this model for detecting respiratory symptoms across different linguistic and geographic contexts suggests a potential path for the development and validation of voice-based tools for broader disease surveillance and monitoring applications in the future.

Cardiac metabolic changes on 18 F-positron emission tomography after thoracic radiotherapy predict for overall survival in esophageal cancer patients.

PURPOSE: Heart doses have been shown to be predictive of cardiac toxicity and overall survival (OS) for esophageal cancer patients. There is potential for functional imaging to provide valuable cardiac information. The purpose of this study was to evaluate the cardiac metabolic dose-response using 18 F-deoxyglucose (FDG)-PET and to assess whether standard uptake value (SUV) changes in the heart were predictive of OS. METHODS: Fifty-one patients with esophageal cancer treated with radiation who underwent pre- and post-treatment FDG-PET scans were retrospectively evaluated. Pre- and post-treatment PET-scans were rigidly registered to the planning CT for each patient. Pre-treatment to post-treatment absolute mean SUV (SUVmean) changes in the heart were calculated to assess dose-response. A dose-response curve was generated by binning each voxel in the heart into 10 Gy dose-bins and analyzing the SUVmean changes in each dose-bin. Multivariate cox proportional hazard models were used to assess whether pre-to-post treatment cardiac SUVmean changes predicted for OS. RESULTS: The cardiac dose-response curve demonstrated a trend of increasing cardiac SUV changes as a function of dose with an average increase of 0.044 SUV for every 10 Gy dose bin. In multivariate analysis, disease stage and SUVmean change in the heart were predictive (p < 0.05) for OS. CONCLUSIONS: Changes in pre- to post-treatment cardiac SUV were predictive of OS with patients having a higher pre- to post-treatment cardiac SUV change surviving longer.

Emergency Department-Initiated Buprenorphine Treatment in a Population with a High Rate of Homelessness: An Observational Study.

BACKGROUND: Buprenorphine is an effective treatment for opioid use disorders. A previous randomized trial comparing emergency department (ED)-initiated buprenorphine to standard care showed dramatic improvement in follow-up. This is encouraging, but must be replicated to understand the generalizability of buprenorphine treatment. OBJECTIVES: Evaluate the efficacy of an ED-initiated buprenorphine protocol similar to a previous randomized trial in a different population. METHODS: This ED-based descriptive study described the results of a project implementing an opioid use disorder treatment protocol that included buprenorphine. Patients with opioid use disorder were offered treatment with buprenorphine, a buprenorphine prescription whenever possible, and a follow-up visit to a clinic providing addiction treatment. The primary outcome was engagement in formal addiction treatment 30 days after the index visit. RESULTS: Of the 210 patients who accepted referral for outpatient medication-assisted treatment, 95 (45.2%) achieved the primary outcome. Two-thirds of these patients received a buprenorphine prescription at discharge; 40% were homeless. A regression analysis revealed one statistically significant predictor of the primary outcome: patients who were housed were 2.49 times more likely to engage in opioid use disorder treatment than patients who were homeless (p = 0.02). CONCLUSIONS: In this descriptive study of an ED-initiated buprenorphine protocol, follow-up was less than that reported in a previous randomized controlled trial. Two important differences between our study and the randomized trial are the high rate of homelessness and the fact that not every patient received a prescription for buprenorphine. The efficacy of ED-initiated treatment may depend on certain population characteristics.

Frequency and Outcomes of Cervical Spine Computed Tomography Imaging on Alcohol-Intoxicated Patients in the Emergency Department.

BACKGROUND: Cervical spinal (c-spine) injuries range greatly in severity from minor ligamentous injuries to osteoligamentous instability with spinal cord injuries. Initial evaluation begins with stabilization as needed and immediate immobilization. Current practice as to whether the c-spine can be cleared clinically without radiographic evaluation is often guided by using the National Emergency X-Radiography Utilization Study Low-Risk Criteria and the Canadian C-Spine Rule. Under these clinical decision guidelines, stable trauma patients presenting with alcohol intoxication cannot have the c-spine cleared clinically and imaging should be "considered." OBJECTIVE: This study aimed to assess the frequency of computed tomography (CT) c-spine scans ordered for patients presenting with alcohol intoxication to the emergency department (ED), the timing of the studies, and subsequently determine the proportion of which showed a clinically significant result that required intervention. METHODS: In this retrospective medical record review, all clinically alcohol-intoxicated patients presenting to two academic EDs were included. Overall demographic characteristics, time to order of CT imaging, radiology reads, and outcomes of patient visits were determined. RESULTS: There were 8008 patient visits included in the study. Of these visits, 5 patients scanned in ≤3 h had acute findings on CT scan and no patients with a deferred timing of CT scan after patients metabolized had an acute finding on CT scan. No patients required operative management. CONCLUSIONS: This study's results suggest that it is a safe clinical practice to defer CT imaging for patients presenting to the ED with alcohol intoxication and low suspicion for c-spine injury per history and examination.

Perceptions and Practices of Cannabis Use Among Emergency Department Patients.

BACKGROUND: Nationally, in states where cannabis has been legalized, increases in cannabis-related hospitalizations and emergency department (ED) visits have also been observed. OBJECTIVES: This study aims to: 1) Describe the sociodemographic characteristics of cannabis users presenting to two academic EDs in California; 2) Assess cannabis-related behaviors; 3) Assess perceptions of cannabis; 4) Identify and describe reasons for cannabis-related ED utilization. METHODS: This is a cross-sectional study of patients visiting one of two academic EDs between February 16, 2018 and November 21, 2020. Eligible participants completed a novel questionnaire developed by the authors. Basic descriptive statistics, Pearson correlation coefficients, and logistic regression were used for statistical analysis of responses. RESULTS: The questionnaire was completed by 2577 patients. A quarter were categorized as Current Users (n = 628, 24.4%). Current, Regular Users were evenly divided across gender, were relatively younger (18-34 years, 48.1%), and were largely non-Hispanic Caucasian. Over half of all respondents believed that the use of cannabis was less harmful than tobacco or alcohol use (n = 1537, 59.6%). One in five Current Users (n = 123, 19.8%) reported driving while using cannabis in the past month. A small proportion (n = 24, 3.9%) of Current Users reported ever visiting the ED for a cannabis-related chief complaint. CONCLUSIONS: Overall, many ED patients are currently using cannabis; few report utilizing the ED due to cannabis-related problems. Current, Irregular Users may represent the ideal target group for ED-based educational efforts aimed at improving knowledge of safe cannabis use.

Impact of Implementation of a New Weapons Screening at an Urban Emergency Department.

BACKGROUND: Violence in the emergency department (ED) setting is well documented in medical literature. Weapons can be used to cause significant injury or mortality, although there is a paucity of literature on weapons and weapons screening in the ED. OBJECTIVES: The purpose of this study was to assess the impact of initiating a weapons screening process on the identification and removal of weapons. METHODS: Multiple aspects of a weapons screening program were evaluated at 2 and 6 months prior to and after a weapons screening protocol was initiated at an urban ED. In the Pre-Screen periods, only patients primarily seeking care for mental health were screened prior to entry. In the Post-Screen periods, all patients and visitors were screened with walk-through magnetometers or wand metal detectors, and additional screening checks were initiated. The number of individuals screened and numbers of weapons found were measured. Descriptive statistics comparing Pre- and Post-Screen periods were performed. RESULTS: Prior to the new screening process, 511 and 1701 patients primarily seeking care for mental health were screened, with 15 and 103 weapons confiscated at 2 and 6 months, respectively. After the screening process was initiated, 13,149 and 43,321 ED patients and visitors were screened, with 194 and 567 weapons confiscated at 2 and 6 months, respectively. Persons screened increased by 25-fold at both 2 and 6 months after implementing the screening process. Weapons confiscated increased approximately 13-fold and sixfold at the respective 2- and 6-month Pre- and Post-Screen periods, respectively. CONCLUSION: Implementation of weapons screening significantly increased the number of weapons identified and confiscated prior to entry in the ED by patients and visitors.

Physiological Effects of a Spit Restraint Device Saturated With Artificial Saliva.

BACKGROUND: Spit restraint devices, also referred to as spit hoods, spit masks, or spit socks, are used by law enforcement and medical personnel to minimize transmission of communicable disease from bodily fluids from agitated individuals. Several lawsuits have implicated spit restraint devices as contributing to the death of individuals who are physically restrained by means of asphyxiation due to saturation of the mesh restraint device with saliva. OBJECTIVES: This study aims to evaluate whether a saturated spit restraint device has any clinically significant effects on the ventilatory or circulatory parameters of healthy adult subjects. METHODS: Subjects wore a spit restraint device dampened with 0.5% carboxymethylcellulose, an artificial saliva. Baseline vitals were taken, and a wet spit restraint device was then placed over the subject's head, and repeat measurements were taken at 10, 20, 30, and 45 min. A second spit restraint device was placed 15 min after the first. Measurements at 10, 20, 30, and 45 min were compared with baseline using paired t-tests. RESULTS: The mean age of 10 subjects was 33.8 years, and 50% were female. There was no significant difference between baseline and while wearing the spit sock for 10, 20, 30, and 45 min for the measured parameters including heart rate, oxygen saturation, end-tidal CO2, respiratory rate, or blood pressure. No subject indicated respiratory distress or had to terminate the study. CONCLUSIONS: In healthy adult subjects, there were no statistically or clinically significant differences in ventilatory or circulatory parameters while wearing the saturated spit restraint.

Heat Waves and Emergency Department Visits Among the Homeless, San Diego, 2012-2019.

Objectives. To determine the effect of heat waves on emergency department (ED) visits for individuals experiencing homelessness and explore vulnerability factors. Methods. We used a unique highly detailed data set on sociodemographics of ED visits in San Diego, California, 2012 to 2019. We applied a time-stratified case-crossover design to study the association between various heat wave definitions and ED visits. We compared associations with a similar population not experiencing homelessness using coarsened exact matching. Results. Of the 24 688 individuals identified as experiencing homelessness who visited an ED, most were younger than 65 years (94%) and of non-Hispanic ethnicity (84%), and 14% indicated the need for a psychiatric consultation. Results indicated a positive association, with the strongest risk of ED visits during daytime (e.g., 99th percentile, 2 days) heat waves (odds ratio = 1.29; 95% confidence interval = 1.02, 1.64). Patients experiencing homelessness who were younger or elderly and who required a psychiatric consultation were particularly vulnerable to heat waves. Odds of ED visits were higher for individuals experiencing homelessness after matching to nonhomeless individuals based on age, gender, and race/ethnicity. Conclusions. It is important to prioritize individuals experiencing homelessness in heat action plans and consider vulnerability factors to reduce their burden. (Am J Public Health. 2022;112(1):98-106. https://doi.org/10.2105/AJPH.2021.306557).

Procalcitonin as a Predictive Tool for Death and ICU Admission among Febrile Neutropenic Patients Visiting the Emergency Department.

Background and Objectives: Risk stratification tools for febrile neutropenia exist but are infrequently utilized by emergency physicians. Procalcitonin may provide emergency physicians with a more objective tool to identify patients at risk of decompensation. Materials and Methods: We conducted a retrospective cohort study evaluating the use of procalcitonin in cases of febrile neutropenia among adult patients presenting to the Emergency Department compared to a non-neutropenic, febrile control group. Our primary outcome measure was in-hospital mortality with a secondary outcome of ICU admission. Results: Among febrile neutropenic patients, a positive initial procalcitonin value was associated with significantly increased odds of inpatient mortality after adjusting for age, sex, race, and ethnicity (AOR 9.912, p < 0.001), which was similar, though greater than, our non-neutropenic cohort (AOR 2.18, p < 0.001). All febrile neutropenic patients with a positive procalcitonin were admitted to the ICU. Procalcitonin had a higher sensitivity and negative predictive value (NPV) in regard to mortality and ICU admission for our neutropenic group versus our non-neutropenic control. Conclusions: Procalcitonin appears to be a valuable tool when attempting to risk stratify patients with febrile neutropenia presenting to the emergency department. Procalcitonin performed better in the prediction of death and ICU admission among patients with febrile neutropenia than a similar febrile, non-neutropenic control group.

Association of anticoagulation dose and survival in hospitalized COVID-19 patients: A retrospective propensity score-weighted analysis.

BACKGROUND: Hypercoagulability may contribute to COVID-19 pathogenicity. The role of anticoagulation (AC) at therapeutic (tAC) or prophylactic doses (pAC) is unclear. OBJECTIVES: We evaluated the impact on survival of different AC doses in COVID-19 patients. METHODS: Retrospective, multi-center cohort study of consecutive COVID-19 patients hospitalized between March 13 and May 5, 2020. RESULTS: A total of 3480 patients were included (mean age, 64.5 years [17.0]; 51.5% female; 52.1% black and 40.6% white). 18.5% (n = 642) required intensive care unit (ICU) stay. 60.9% received pAC (n = 2121), 28.7% received ≥3 days of tAC (n = 998), and 10.4% (n = 361) received no AC. Propensity score (PS) weighted Kaplan-Meier plot demonstrated different 25-day survival probability in the tAC and pAC groups (57.5% vs 50.7%). In a PS-weighted multivariate proportional hazards model, AC was associated with reduced risk of death at prophylactic (hazard ratio [HR] 0.35 [95% confidence interval {CI} 0.22-0.54]) and therapeutic doses (HR 0.14 [95% CI 0.05-0.23]) compared to no AC. Major bleeding occurred more frequently in tAC patients (81 [8.1%]) compared to no AC (20 [5.5%]) or pAC (46 [2.2%]) subjects. CONCLUSIONS: Higher doses of AC were associated with lower mortality in hospitalized COVID-19 patients. Prospective evaluation of efficacy and risk of AC in COVID-19 is warranted.

Extubation Failure in Critically Ill COVID-19 Patients: Risk Factors and Impact on In-Hospital Mortality.

PURPOSE: We sought to identify clinical factors that predict extubation failure (reintubation) and its prognostic implications in critically ill COVID-19 patients. MATERIALS AND METHODS: Retrospective, multi-center cohort study of hospitalized COVID-19 patients. Multivariate competing risk models were employed to explore the rate of reintubation and its determining factors. RESULTS: Two hundred eighty-one extubated patients were included (mean age, 61.0 years [±13.9]; 54.8% male). Reintubation occurred in 93 (33.1%). In multivariate analysis accounting for death, reintubation risk increased with age (hazard ratio [HR] 1.04 per 1-year increase, 95% confidence interval [CI] 1.02 -1.06), vasopressors (HR 1.84, 95% CI 1.04-3.60), renal replacement (HR 2.01, 95% CI 1.22-3.29), maximum PEEP (HR 1.07 per 1-unit increase, 95% CI 1.02 -1.12), paralytics (HR 1.48, 95% CI 1.08-2.25) and requiring more than nasal cannula immediately post-extubation (HR 2.19, 95% CI 1.37-3.50). Reintubation was associated with higher mortality (36.6% vs 2.1%; P < 0.0001) and risk of inpatient death after adjusting for multiple factors (HR 23.2, 95% CI 6.45-83.33). Prone ventilation, corticosteroids, anticoagulation, remdesivir and tocilizumab did not impact the risk of reintubation or death. CONCLUSIONS: Up to 1 in 3 critically ill COVID-19 patients required reintubation. Older age, paralytics, high PEEP, need for greater respiratory support following extubation and non-pulmonary organ failure predicted reintubation. Extubation failure strongly predicted adverse outcomes.

Evaluation of the ventilatory effects on human subjects in prolonged hip-flexed/head-down restraint position.

BACKGROUND: The restraint chair is a tool used by law enforcement and correction personnel to control aggressive, agitated individuals. When initiating its use, subjects are often placed in a hip-flexed/head-down (HFHD) position to remove handcuffs. Usually, this period of time is less than two minutes but can become more prolonged in particularly agitated patients. Some have proposed this positioning limits ventilation and can result in asphyxia. The aim of this study is to evaluate if a prolonged HFHD restraint position causes significant ventilatory compromise. METHODS: Subjects exercised on a stationary bicycle until they reached 85% of their predicted maximal heart rate. They were then handcuffed with their hands behind their back and placed into a HFHD seated position for five minutes. The primary outcome measurement was maximal voluntary ventilation (MVV). This was measured at baseline, after initial placement into the HFHD position, and after five minutes of being in the position while still maintaining the HFHD position. Baseline measurements were compared with final measurements for statistically significant differences. RESULTS: We analyzed data for 15 subjects. Subjects had a mean MVV of 165.3 L/min at baseline, 157.8 L/min after initially being placed into the HFHD position, and a mean of 138.7 L/min after 5 min in the position. The mean baseline % predicted MVV was 115%; after 5 min in the HFHD position the mean was 96%. This 19% absolute difference was statistically significant (p = 0.001). CONCLUSIONS: In healthy seated male subjects with recent exertion, up to five minutes in a HFHD position results in a small decrease in MVV compared with baseline MVV levels. Even with this decrease, mean MVV levels were still 96% of predicted after five minutes. Though a measurable decrease was found, there was no clinically significant change that would support that this positioning would lead to asphyxia over a five-minute time period.

Functional avoidance-based intensity modulated proton therapy with 4DCT derived ventilation imaging for lung cancer.

The primary objective is to evaluate the potential dosimetric gains of performing functional avoidance-based proton treatment planning using 4DCT derived ventilation imaging. 4DCT data of 31 patients from a prospective functional avoidance clinical trial were evaluated with intensity modulated proton therapy (IMPT) plans and compared with clinical volumetric modulated arc therapy (VMAT) plans. Dosimetric parameters were compared between standard and functional plans with IMPT and VMAT with one-way analysis of variance and post hoc paired student t-test. Normal Tissue Complication Probability (NTCP) models were employed to estimate the risk of two toxicity endpoints for healthy lung tissues. Dose degradation due to proton motion interplay effect was evaluated. Functional IMPT plans led to significant dose reduction to functional lung structures when compared with functional VMAT without significant dose increase to Organ at Risk (OAR) structures. When interplay effect is considered, no significant dose degradation was observed for the OARs or the clinical target volume (CTV) volumes for functional IMPT. Using fV20 as the dose metric and Grade 2+ pneumonitis as toxicity endpoint, there is a mean 5.7% reduction in Grade 2+ RP with the functional IMPT and as high as 26% in reduction for individual patient when compared to the standard IMPT planning. Functional IMPT was able to spare healthy lung tissue to avoid excess dose to normal structures while maintaining satisfying target coverage. NTCP calculation also shows that the risk of pulmonary complications can be further reduced with functional based IMPT.

Developing and Implementing a Geriatric Emergency Department (GED): Overview and Characteristics of GED Visits.

BACKGROUND: The traditional model of emergency care may not be sufficient to address the complex care needs of older adults, who present to the emergency department with multiple comorbidities, geriatric syndromes, and social determinants of health, complicating diagnosis and management. Geriatric emergency departments (GEDs) have emerged throughout the last decade to address these concerns and improve the emergency care of older adults. OBJECTIVE: Our aim was to describe the policies, procedures, and workflow of our GEDs, and to provide data on patient outcomes and discuss challenges and recommendations in the development and implementation of a GED. DISCUSSION: Our GED includes interdisciplinary staff trained in geriatric emergency medicine, evidence-based protocols for geriatric care, physical modifications to accommodate older adults' functional limitations, administration of geriatric assessments, care coordination with case managers and social workers, and referrals to care. Assessments screen for geriatric syndromes and social determinants of health. Quality improvement is a critical component and includes a robust medication safety plan to reduce use of potentially inappropriate medications. Hospital administrators considering developing a GED should create a care planning team, conduct an institutional needs assessment, and identify the GED model that will most efficiently help them achieve an age-friendly health system. CONCLUSIONS: The GED will play an important role in addressing the diverse health care needs of older adults in the coming decades. Future research studies of health outcomes among older adults receiving care at GEDs compared with traditional EDs will be critical in informing future improvements and innovations in geriatric emergency care.

Ethnic Disparities in COVID-19 Among Older Adults Presenting to the Geriatric Emergency Department.

BACKGROUND: There is a dearth of epidemiological data on ethnic disparities among older patients with COVID-19. The objective of this study was to characterize ethnic differences in clinical presentation and outcomes from COVID-19 among older U.S. adults. METHODS: This was a retrospective cohort study within two geriatric emergency departments (GEDs) at a large academic health system. One hundred patients 65 years or older who visited a GED between March 10, 2020 and August 9, 2020 and tested positive for COVID-19 were examined. Electronic medical records were used to determine presenting COVID-19-related symptoms, comorbidities, and clinical outcomes. Descriptive statistics are reported with associated 95% confidence intervals (CIs). RESULTS: In the overall sample, mean age was 75.9 years; 18% were 85 years or older; 50% were male; and 46.0% were Hispanic. Relative to non-Hispanic patients with COVID-19, Hispanic patients with COVID-19 had a higher percentage of shortness of breath (78.3% vs. 51.9%; difference: 26.4%; 95% CI 7.6-42.5%), pneumonia (82.6% vs. 50.0%; difference: 32.6%; 95% CI 14.1-47.9%), acute respiratory distress syndrome (13.0% vs. 1.9%; difference: 11.1%; 95% CI 0.7-23.9%), and acute kidney failure (41.3% vs. 22.2%; difference: 19.1%; 95% CI 0.9-36.0%). Rates of other poor outcomes, including hospitalization, intensive care unit (ICU) admission, return visits to the GED within 30 days of discharge, or death, did not significantly differ between Hispanic and non-Hispanic patients with COVID-19. CONCLUSIONS: These preliminary data show that older Hispanic patients relative to non-Hispanic patients with COVID-19 presenting to a GED did not experience worse outcomes, including hospitalization, ICU admission, 30-day return visits to the GED, or death.

Active Cancer Patients Presenting to the Emergency Department with Acute Venous Thromboembolism: A Retrospective Cohort Study on Risks and Outcomes.

BACKGROUND: There is no prior study that has documented emergency department (ED) outcomes or stratified mortality risks of cancer patients presenting with an acute venous thromboembolism (VTE). OBJECTIVE: To evaluate ED treatment of these patients, to document their outcomes, and to identify risk factors associated with death. METHODS: A retrospective cohort study was performed on active cancer patients presenting with deep venous thrombosis or pulmonary embolism to two academic EDs between July 2012 and June 2016. Key outcomes included mortality, ED revisit, and admission within 30 days. The patient cohort was characterized; crosstabs and regression analysis were performed to assess relative risks (RRs) and mitigating factors associated with 30-day mortality. RESULTS: Of 355 patients, 9% died and 38% had one or more ED revisits or admissions. Recent immobility (RR 2.341, 95% CI 1.227-4.465), poor functional status (RR 2.090, 95% CI 1.028-4.248), recent admission (RR 2.441, 95% CI 1.276-4.669), and metastatic cancer (RR 4.669, 95% CI 1.456-14.979) were major risk factors for mortality. ED-provided anticoagulation reduced the overall mortality risk (RR 0.274, 95% CI 0.146-0.515) and mitigated the risk from recent immobility (RR 1.250, 95% CI 0.462-3.381), especially among patients with good or fair functional status. CONCLUSION: Immobility and cancer morbidity are key risk factors for mortality after an acute VTE, but ED-provided anticoagulation mitigates the risk of immobility among healthier patients. Eastern Cooperative Oncology Group performance status can help clinicians risk stratify these patients at presentation.

Trends in emergency physician opioid prescribing practices during the United States opioid crisis.

BACKGROUND: Prescription opioid related deaths have increased dramatically over the past 17 years. Although emergency physicians (EPs) have not been the primary force behind this rise, previous literature have suggested that EPs could improve their opioid prescribing practices. We designed this study to evaluate the trend in emergency department (ED) opioid prescriptions over time during the US opioid epidemic. METHODS: We conducted a retrospective cohort study from July 1, 2012 to June 30, 2018, evaluating all adult patients who presented to two study EDs for a pain-related complaint and received an analgesic prescription upon ED discharge. We compared these data to trends in lay media and medical literature regarding the opioid epidemic. We also evaluated the incidence of repeat ED visits based on the type of analgesic prescriptions provided. RESULTS: Opioid prescriptions decreased from 37.76% to 13.29% over the six year study period. This coupled with an increase in non-opioid medications from 6.12% to 11.33% and an increase in "no prescription" from 56.12% to 75.37%. This corresponded with an increase in the number of publications on the opioid epidemic within the lay-public and medical literature. Additionally, those patients that received no opiates were less likely to require a repeat ED visit. CONCLUSIONS: ED physicians are prescribing less opiates, while increasing the amount of non-narcotic analgesic prescriptions. This may be in response to the literature suggesting that prescription opioids play a large role in the opioids crisis. This decrease in opioid prescriptions did not increase the need for repeat ED visits.

Deep convolutional neural networks for automatic segmentation of thoracic organs-at-risk in radiation oncology - use of non-domain transfer learning.

PURPOSE: Segmentation of organs-at-risk (OARs) is an essential component of the radiation oncology workflow. Commonly segmented thoracic OARs include the heart, esophagus, spinal cord, and lungs. This study evaluated a convolutional neural network (CNN) for automatic segmentation of these OARs. METHODS: The dataset was created retrospectively from consecutive radiotherapy plans containing all five OARs of interest, including 22,411 CT slices from 168 patients. Patients were divided into training, validation, and test datasets according to a 66%/17%/17% split. We trained a modified U-Net, applying transfer learning from a VGG16 image classification model trained on ImageNet. The Dice coefficient and 95% Hausdorff distance on the test set for each organ was compared to a commercial atlas-based segmentation model using the Wilcoxon signed-rank test. RESULTS: On the test dataset, the median Dice coefficients for the CNN model vs. the multi-atlas model were 71% vs. 67% for the spinal cord, 96% vs. 94% for the right lung, 96%vs. 94% for the left lung, 91% vs. 85% for the heart, and 63% vs. 37% for the esophagus. The median 95% Hausdorff distances were 9.5  mm vs. 25.3 mm, 5.1  mm vs. 8.1 mm, 4.0  mm vs. 8.0 mm, 9.8  mm vs. 15.8 mm, and 9.2 mm vs. 20.0 mm for the respective organs. The results all favored the CNN model (P < 0.05). CONCLUSIONS: A 2D CNN can achieve superior results to commercial atlas-based software for OAR segmentation utilizing non-domain transfer learning, which has potential utility for quality assurance and expediting patient care.

Frequent Emergency Department Visitors Associated With a Pain-Discharge Diagnosis.

BACKGROUND: Emergency departments (EDs) have experienced an increase in annual patient visits and length of stay over the past decade. Management of frequent-user patients with pain-related diagnoses are challenging in a time-limited setting. OBJECTIVE: The purpose of this study was to describe characteristics of frequent ED users with pain-related diagnoses. METHODS: This was a retrospective longitudinal cohort study of hospital ED visits from two EDs in using encounters from September 2016 to August 2018. Frequent users were characterized as having four or more visits in a 1-year period and were further classified into three categories based on the number of pain-related visits in the study period. Descriptive statistics and regression analysis results are reported for all demographic and clinical characteristics for index encounters, patient level data, and pain subgroups. RESULTS: Of all patients, 11.3% (n = 5174) were identified as frequent users, accounting for 38.9% (n = 91,114) of all ED visits. Overall, frequent pain users were more likely to be of middle age (odds ratio [OR] 1.70, 95% confidence interval [CI] 0.80-1.72), female (OR 2.43, 95% CI 1.79-3.29), have commercial insurance (OR 1.91, 95% CI 1.37-2.66), and have 10 or more ED encounters (super user status) in a 12-month period (OR 23.66, 95% CI 17.12-32.71). CONCLUSION: Understanding characteristics of ED frequent users with pain-related diagnoses may inform community-based interventions designed to reduce episodic care and thereby improve care coordination and management.