Characteristics of COVID-19 patients with bacterial coinfection admitted to the hospital from the emergency department in a large regional healthcare system

Introduction

The rate of bacterial coinfection with SARS‐CoV‐2 is poorly defined. The decision to administer antibiotics early in the course of SARS‐CoV‐2 infection depends on the likelihood of bacterial coinfection.

Methods

We performed a retrospective chart review of all patients admitted through the emergency department with confirmed SARS‐CoV‐2 infection over a 6‐week period in a large healthcare system in the United States. Blood and respiratory culture results were abstracted and adjudicated by multiple authors. The primary outcome was the rate of bacteremia. We secondarily looked to define clinical or laboratory features associated with bacteremia.

Results

There were 542 patients admitted with confirmed SARS‐CoV‐2 infection, with an average age of 62.8 years. Of these, 395 had blood cultures performed upon admission, with six true positive results (1.1% of the total population). An additional 14 patients had positive respiratory cultures treated as true pathogens in the first 72 h. Low blood pressure and elevated white blood cell count, neutrophil count, blood urea nitrogen, and lactate were statistically significantly associated with bacteremia. Clinical outcomes were not statistically significantly different between patients with and without bacteremia.

Conclusions

We found a low rate of bacteremia in patients admitted with confirmed SARS‐CoV‐2 infection. In hemodynamically stable patients, routine antibiotics may not be warranted in this population.

Incidence of Venous Thromboembolism in Critically Ill Coronavirus Disease 2019 Patients Receiving Prophylactic Anticoagulation

OBJECTIVES

One of the defining features of the novel coronavirus disease 2019 infection has been high rates of venous thromboses. The present study aimed to describe the prevalence of venous thromboembolism in critically ill patients receiving different regimens of prophylactic anticoagulation.

DESIGN

Single-center retrospective review using data from patients with confirmed severe acute respiratory syndrome coronavirus 2 requiring intubation.

SETTING

Tertiary-care center in Indianapolis, IN, United States.

PATIENTS

Patients hospitalized at international units Health Methodist Hospital with severe acute respiratory syndrome coronavirus 2 requiring intubation between March 23, 2020, and April 8, 2020, who underwent ultrasound evaluation for venous thrombosis.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

A total of 45 patients were included. Nineteen of 45 patients (42.2%) were found to have deep venous thrombosis. Patients found to have deep venous thrombosis had no difference in time to intubation (p = 0.97) but underwent ultrasound earlier in their hospital course (p = 0.02). Sequential Organ Failure Assessment scores were similar between the groups on day of intubation and day of ultrasound (p = 0.44 and p = 0.07, respectively). D-dimers were markedly higher in patients with deep venous thrombosis, both for maximum value and value on day of ultrasound (p < 0.01 for both). Choice of prophylactic regimen was not related to presence of deep venous thrombosis (p = 0.35). Ultrasound evaluation is recommended if D-dimer is greater than 2,000 ng/mL (sensitivity 95%, specificity 46%) and empiric anticoagulation considered if D-dimer is greater than 5,500 ng/mL (sensitivity 53%, specificity 88%).

CONCLUSIONS

Deep venous thrombosis is very common in critically ill patients with coronavirus disease 2019. There was no difference in incidence of deep venous thrombosis among different pharmacologic prophylaxis regimens, although our analysis is limited by small sample size. D-dimer values are elevated in the majority of these patients, but there may be thresholds at which screening ultrasound or even empiric systemic anticoagulation is indicated.

Troponin Testing and Coronary Syndrome in Geriatric Patients With Nonspecific Complaints: Are We Overtesting?

BACKGROUND

Elderly patients presenting to the emergency department (ED) with nonspecific complaints (NSCs) often undergo troponin testing to assess for atypical acute coronary syndrome (ACS). However, the rate of ACS and utility of troponin testing in this population is unknown. We sought to determine the rate of ACS and diagnostic yield of troponin testing in elderly patients with NSCs.

METHODS

We retrospectively identified all patients aged ≥ 65 years triaged in the ED with NSCs from January 1, 2017, to June 30, 2017. NSCs were defined a priori and included complaints such as weakness, dizziness, or fatigue. NSCs were verified in ED provider notes by trained abstractors blind to testing results. Exclusions were focal chief complaint in provider notes, fever, and no troponin ordered. ACS was strictly defined and independently adjudicated by two trained physician researchers blind to the study hypothesis. We calculated the proportion of patients with ACS within 30 days and the test characteristics of troponin to diagnose ACS.

RESULTS

Screening identified 1,146 encounters, and 552 were excluded for fever or focal chief complaints in the provider notes. Of the remaining 594 patients, troponin was ordered in 412 (69%), comprising the study cohort. The mean (±SD) age was 78.7 (±8.3) years, with 58% female and 75% admitted. Troponin elevation occurred in 81 patients (20%). ACS occurred in 5 of 412 (1.2%). Troponin was 100% sensitive (95% confidence interval [CI] = 48% to 100%) and 81% specific (95% CI = 77% to 85%) for ACS. Of patients with elevated troponin, 93.8% were false positives (no ACS). All patients with troponin elevation were admitted, but only one underwent angiography and no patients received reperfusion therapy.

CONCLUSIONS

While consideration for ACS is prudent in selected elderly patients with NSCs, ACS was rare and no patients received reperfusion therapy. Given the false-positive rate in our study, our results may not support routine troponin testing for ACS in this population.

Socioeconomic Factors for Sports Specialization and Injury in Youth Athletes

Background:

The effect of socioeconomic status (SES) on rates of sports specialization and injury among youth athletes has not been described previously.

Hypothesis:

Young athletes from lower socioeconomic status will have lower rates of sports specialization and subsequently lower risk of overuse injuries.

Study Design:

Cohort study.

Level of Evidence:

Level 3.

Methods:

Injured athletes aged 7 to 18 years were recruited from 2 hospital-based sports medicine clinics and compared with uninjured athletes presenting for sports physicals at primary care clinics between 2010 and 2013. Participants completed surveys on training patterns. Electronic medical records provided injury details as well as patient zip code, race, and health insurance type. SES was estimated from zip codes. The sample was divided into SES tertiles. Analysis of variance and multivariate regression were used for continuous variables, and multivariate logistic regression analyses were conducted to explore relationships between risk factors and injury.

Results:

Of 1190 athletes surveyed, 1139 (96%) had satisfactory SES data. Compared with low-SES athletes, high-SES athletes reported more hours per week spent playing organized sports (11.2 ± 6.0 vs 10.0 ± 6.5; P = 0.02), trained more months per year in their main sport (9.7 ± 3.1 vs 7.6 ± 3.7; P < 0.01), were more often highly specialized (38.9% vs 16.6%; P < 0.01), and had increased participation in individual sports (64.8% vs 40.0%; P < 0.01). The proportion of athletes with a greater than 2:1 ratio of weekly hours in organized sports to free play increased with SES. Accounting for age and weekly organized sports hours, the odds of reporting a serious overuse injury increased with SES (odds ratio, 1.5; P < 0.01).

Conclusion:

High-SES athletes reported more serious overuse injuries than low-SES athletes, potentially due to higher rates of sports specialization, more hours per week playing organized sports, higher ratio of weekly hours in organized sports to free play, and greater participation in individual sports.

Clinical Relevance:

As SES increases, young athletes report higher degrees of sports specialization, greater participation in individual sports, and more serious overuse injuries.

Understanding Charge Transport in Molecular Electronics

For molecular electronics to become a viable technology the factors that control charge transport across a metal-molecule-metal junction need to be elucidated. We use an experimentally simple crossed-wire tunnel junction to interrogate how factors such as metal-molecule coupling, molecular structure, and the choice of metal electrode influence the current-voltage characteristics of a molecular junction.

Metal-molecule contacts and charge transport across monomolecular layers: measurement and theory

Charge transport studies across molecular length scales under symmetric and asymmetric metal-molecule contact conditions using a simple crossed-wire tunnel junction technique are presented. It is demonstrated that oligo(phenylene ethynylene), a conjugated organic molecule, acts like a molecular wire under symmetric contact conditions, but exhibits characteristics of a molecular diode when the connections are asymmetric. To understand this behavior, we have calculated current-voltage (I-V) characteristics using extended Huckel theory coupled with a Green's function approach. The experimentally observed I-V characteristics are in excellent qualitative agreement with the theory.

Explosives detection in soil using a field-portable continuous flow immunosensor

A field method for quantitative analysis of explosives in contaminated soil samples is described. The method is based on a displacement immunoassay performed in a commercial instrument, the FAST 2000, engineered by Research International Inc. The method can be used on-site to measure 2,4,6-trinitrotoluene (TNT) and hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) within 5min. For this study, replicate analyses were performed on soil extracts prepared from each field sample as well as appropriate controls, blanks, and laboratory standards. Statistical analyses were done to assess accuracy, bias, and predictability of the method. The results demonstrated that the immunosensor could be used effectively to screen environmental samples for the presence or absence of explosives. In most samples, the method also provided quantitative values that were in good agreement with standard laboratory analyses using HPLC. A limited number of sample matrices interfered with the immunoassay and produced results that varied significantly from the laboratory data. In each case, the compounds causing the problem have been identified and efforts are being made to minimize these matrix interferences in future field evaluations.

Continuous flow displacement immunosensors: a computational study

Numerical modeling has been used to investigate the disparity in performance and sensitivity that has been reported for flow displacement immunosensors based on bead-packed columns, membranes, and capillary tubes. The simulations strongly suggest that the high surface areas in the porous media systems may actually be detrimental to sensor performance because of large numbers of free antibody binding sites. Since the free antibody sites are created during the wash step in which the baseline is established, wash protocols are critical in optimizing the sensitivity for a given displacement sensor.

Antiphase disorder in GaAs/Ge heterostructures for solar cells

Antiphase disorder in metal organic vapour phase epitaxy grown GaAs/(100)Ge heterostructures has been studied both in as-grown materials and in GaAs solar cells by chemical etching, transmission electron microscopy, and cathodoluminescence. All the samples are single domains at the surface due to the self-annihilation of antiphase domains whose size decreases as the misorientation angle increases. Completely antiphase domain-free epitaxy has been achieved for substrate miscuts greater than 3 degrees off towards [111]. A reversal in sublattice location has been found in the GaAs layers varying the misorientation angle and the growth temperature. A model to explain this result has been proposed based on the role of surface steps in the nucleation process. Strong interaction between antiphase boundaries and misfit dislocations has been found in all the heterostructures. In solar cells antiphase domains have been observed in high densities in the initial layer of GaAs deposited on Ge. The successful realisation of high efficiency solar cells is due to the overgrowth of these domains by single phase material over most of the wafer area.

Electroclinic liquid crystals with large induced tilt angle and small layer contraction

Optical and x-ray scattering studies of a chiral, organosiloxane smectic-A liquid crystal indicate a large field induced optical tilt of up to 31 degrees accompanied by a very small contraction of the smectic layers. This result suggests that the molecules have a nonzero tilt even with no applied field, and that the primary effect of the field is to induce long range order in the direction of the molecular tilt.

The remote electron beam-induced current analysis of grain boundaries in semiconducting and semi-insulating materials

When no charge collecting p-n junction or Schottky barrier is present in the specimen, but two contacts are applied, conductive mode scanning electron microscope (SEM) observations known as remote electron beam-induced current (REBIC) can be made. It was described as "remote" EBIC because the contacts to the specimen can lie at macroscopic distances from the beam impact point. In recent years, REBIC has been found to be useful not only for studies of grain boundaries in semiconducting silicon and germanium, but also in semi-insulating materials such as the wider bandgap II-VI compounds and electroceramic materials like varistor ZnO and positive temperature coefficient resistor (PTCR) BaTiO3. The principles of this method are outlined. Accounts are given of the five forms of charge collection and resistive contrast that appear at grain boundaries (GBs) in REBIC micrographs. These are (1) terraced contrast due to high resistivity boundary layers, (2) peak and trough (PAT) contrast due to charge on the boundary, (3) reversible contrast seen only under external voltage bias due to the beta-conductive effect in a low conductivity boundary layer, (4) dark contrast due to enhanced recombination, and (5) bright contrast apparently due to reduced recombination. For comparison, the results of the extensive EBIC studies of GBs in Si and Ge are first outlined and then the results of recent REBIC grain boundary studies in both semiconducting and semi-insulating materials are reviewed.

Fabrication of resorbable microporous intravascular stents for gene therapy applications

The authors have produced resorbable, microporous endoluminal stents from Poly-L-lactic acid (PLLA)/Poly epsilon-caprolactone (PCL) blends. Both helical and tube stent designs have been obtained by solvent casting and flotation-precipitation fabrication techniques. A range of PLLA/PCL blend ratios and process variables were employed to investigate their influence on mechanical properties, porosity, and degradation rate. Polymer blends with higher PLLA proportions exhibit higher elastic moduli and ultimate tensile strength, and lower elongation, porosity, and degradation rates than do materials with higher PCL content. Stents with suitable mechanical properties for deployment and support of the vessel wall were obtained. Poly(ethylene oxide) was incorporated into these devices using an acid swelling technique, opening the pore structure and improving the hydrophilic character, thereby enabling the uptake of recombinant adenoviral vectors. The 50:50 PLLA/PCL blended stents were impregnated with recombinant adenovirus (AdCMB beta Gal, encoding a nuclear localizing variant of Escherichia coli beta-galactosidase). Cultured CV-1 cells incubated with stents impregnated with the recombinant virus expressed nuclear localized beta-galactosidase activity, confirming that absorbed virus is released from the matrix in an infectious form, with kinetics suggesting that genetically enhanced endovascular devices of this design are feasible.

Endothelial cell binding to Dacron modified with polyethylene oxide and peptide

Polyethylene oxide (PEO) was incorporated into the surface of Dacron (PET) vascular prosthetic material (crimped Bionit I, BNl) followed by covalent attachment of an endothelial cell (EC) adhesion peptide; Gly-Arg-Glu-Asp-Val-Tyr (GREDVY). This procedure provides the possibility of a surface selective for EC adherence. Optimal PEO incorporation with minimal fiber damage was achieved from 78% (vol) trifluoroacetic acid (TFA) as characterized by scanning electron microscopy, nuclear magnetic resonance, bromphenol blue staining, and tensile testing. By weight, there was 4.4 times as much 18.5kD PEO as 1.5kD PEO incorporated into PET, but there were 2.8 times as many molecules of low molecular weight PEO. Attachment of 125I-GREDVY to substrates increased as follows: BNJ < BNI - 18.5 kD PEO < BNI - 1.5 kD PEO. Polyethylene oxide size affected EC binding with high molecular weight material decreasing binding and low molecular weight PEO increasing attachment. GREDVY modification of BNI or either of the two BNI-PEOs gave small but consistently increased EC binding compared with the same preparation without GREDVY. In contrast, human fibroblasts cultured from umbilical vein showed decreased binding when GREDVY was attached to BNI or PEO modified BNI. These results indicate that selective EC binding to PET vascular prostheses can be achieved.

Developing an in-house physician advisor program

The rapid rise in health care costs during the 1980s has led to a growing demand for utilization management companies, supported by teams of physician advisors. The increasing involvement of physician advisors in day-to-day case review has also led to a growing necessity for their being hired on an in-house basis. This article attempts to show a basic process for developing a functional and efficient in-house physician advisor program.