Health care workers (HCWs) are at risk for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection.
To examine the burden of SARS-CoV-2, SARS-CoV-1, and Middle East respiratory ...syndrome (MERS)-CoV on HCWs and risk factors for infection, using rapid and living review methods.
Multiple electronic databases, including the WHO database of publications on coronavirus disease and the medRxiv preprint server (2003 through 27 March 2020, with ongoing surveillance through 24 April 2020), and reference lists.
Studies published in any language reporting incidence of or outcomes associated with coronavirus infections in HCWs and studies on the association between risk factors (demographic characteristics, role, exposures, environmental and administrative factors, and personal protective equipment PPE use) and HCW infections. New evidence will be incorporated on an ongoing basis by using living review methods.
One reviewer abstracted data and assessed methodological limitations; verification was done by a second reviewer.
64 studies met inclusion criteria; 43 studies addressed burden of HCW infections (15 on SARS-CoV-2), and 34 studies addressed risk factors (3 on SARS-CoV-2). Health care workers accounted for a significant proportion of coronavirus infections and may experience particularly high infection incidence after unprotected exposures. Illness severity was lower than in non-HCWs. Depression, anxiety, and psychological distress were common in HCWs during the coronavirus disease 2019 outbreak. The strongest evidence on risk factors was on PPE use and decreased infection risk. The association was most consistent for masks but was also observed for gloves, gowns, eye protection, and handwashing; evidence suggested a dose-response relationship. No study evaluated PPE reuse. Certain exposures (such as involvement in intubations, direct patient contact, or contact with bodily secretions) were associated with increased infection risk. Infection control training was associated with decreased risk.
There were few studies on risk factors for SARS-CoV-2, the studies had methodological limitations, and streamlined rapid review methods were used.
Health care workers experience significant burdens from coronavirus infections, including SARS-CoV-2. Use of PPE and infection control training are associated with decreased infection risk, and certain exposures are associated with increased risk.
World Health Organization.
In children undergoing heart surgery, nitric oxide administered into the gas flow of the cardiopulmonary bypass oxygenator may reduce postoperative low cardiac output syndrome, leading to improved ...recovery and shorter duration of respiratory support. It remains uncertain whether nitric oxide administered into the cardiopulmonary bypass oxygenator improves ventilator-free days (days alive and free from mechanical ventilation).
To determine the effect of nitric oxide applied into the cardiopulmonary bypass oxygenator vs standard care on ventilator-free days in children undergoing surgery for congenital heart disease.
Double-blind, multicenter, randomized clinical trial in 6 pediatric cardiac surgical centers in Australia, New Zealand, and the Netherlands. A total of 1371 children younger than 2 years undergoing congenital heart surgery were randomized between July 2017 and April 2021, with 28-day follow-up of the last participant completed on May 24, 2021.
Patients were assigned to receive nitric oxide at 20 ppm delivered into the cardiopulmonary bypass oxygenator (n = 679) or standard care cardiopulmonary bypass without nitric oxide (n = 685).
The primary end point was the number of ventilator-free days from commencement of bypass until day 28. There were 4 secondary end points including a composite of low cardiac output syndrome, extracorporeal life support, or death; length of stay in the intensive care unit; length of stay in the hospital; and postoperative troponin levels.
Among 1371 patients who were randomized (mean SD age, 21.2 23.5 weeks; 587 girls 42.8%), 1364 (99.5%) completed the trial. The number of ventilator-free days did not differ significantly between the nitric oxide and standard care groups, with a median of 26.6 days (IQR, 24.4 to 27.4) vs 26.4 days (IQR, 24.0 to 27.2), respectively, for an absolute difference of -0.01 days (95% CI, -0.25 to 0.22; P = .92). A total of 22.5% of the nitric oxide group and 20.9% of the standard care group developed low cardiac output syndrome within 48 hours, needed extracorporeal support within 48 hours, or died by day 28, for an adjusted odds ratio of 1.12 (95% CI, 0.85 to 1.47). Other secondary outcomes were not significantly different between the groups.
In children younger than 2 years undergoing cardiopulmonary bypass surgery for congenital heart disease, the use of nitric oxide via cardiopulmonary bypass did not significantly affect the number of ventilator-free days. These findings do not support the use of nitric oxide delivered into the cardiopulmonary bypass oxygenator during heart surgery.
anzctr.org.au Identifier: ACTRN12617000821392.
We present the spectroscopic evolution of AT 2017gfo, the optical counterpart of the first binary neutron star (BNS) merger detected by LIGO and Virgo, GW170817. While models have long predicted that ...a BNS merger could produce a kilonova (KN), we have not been able to definitively test these models until now. From one day to four days after the merger, we took five spectra of AT 2017gfo before it faded away, which was possible because it was at a distance of only 39.5 Mpc in the galaxy NGC 4993. The spectra evolve from blue (∼6400 K) to red (∼3500 K) over the three days we observed. The spectra are relatively featureless-some weak features exist in our latest spectrum, but they are likely due to the host galaxy. However, a simple blackbody is not sufficient to explain our data: another source of luminosity or opacity is necessary. Predictions from simulations of KNe qualitatively match the observed spectroscopic evolution after two days past the merger, but underpredict the blue flux in our earliest spectrum. From our best-fit models, we infer that AT 2017gfo had an ejecta mass of 0.03 M , high ejecta velocities of 0.3c, and a low mass fraction ∼10−4 of high-opacity lanthanides and actinides. One possible explanation for the early excess of blue flux is that the outer ejecta is lanthanide-poor, while the inner ejecta has a higher abundance of high-opacity material. With the discovery and follow-up of this unique transient, combining gravitational-wave and electromagnetic astronomy, we have arrived in the multi-messenger era.
Abstract Time-resolved SALT spectra of the short-period, dipping X-ray transient, Swift J1357.2−0933, during its 2017 outburst has revealed broad Balmer and He ii λ4686 absorption features, ...blueshifted by ∼600 km s−1. Remarkably these features are also variable on the ∼500 s dipping period, indicating their likely association with structure in the inner accretion disc. We interpret this as arising in a dense, hot (≳30 000 K) outflowing wind seen at very high inclination, and draw comparisons with other accretion disc corona sources. We argue against previous distance estimates of 1.5 kpc and favour a value ≳6 kpc, implying an X-ray luminosity LX ≳ 4 × 1036 erg s−1. Hence it is not a very faint X-ray transient. Our preliminary 1D Monte Carlo radiative transfer and photoionization calculations support this interpretation, as they imply a high intrinsic LX, a column density NH ≳ 1024 cm−2, and a low covering factor for the wind. Our study shows that Swift J1357.2−0933 is truly remarkable amongst the cohort of luminous, Galactic X-ray binaries, showing the first example of He ii λ4686 absorption, the first (and only) variable dip period and is possibly the first black hole ‘accretion disc corona’ candidate.
Purpose
To test the ability of shutter‐speed dynamic contrast‐enhanced (DCE) MRI to estimate water exchange (WX) using simulations and assess its performance in clinical case studies of malignant and ...benign breast tumors.
Methods
Data were simulated using a 1‐compartment tracer kinetic (TK) model combined with a 2‐pool WX model (2PX) and with a 2‐compartment TK model. Typical DCE‐MRI acquisition parameters were used with both WX‐sensitive (8°) and ‐insensitive (25°) flip angles. Clinical data were obtained from patients with malignant and benign breast tumors. Data were fitted using a 2‐compartment TK model and a 1‐compartment TK model combined with 4 WX models: fast exchange limit (FXL), no exchange, 2PX, and shutter‐speed.
Results
Fits to the 1‐compartment simulated data were excellent, but estimates of WX obtained using the 2PX and shutter‐speed models were poor. One‐compartment TK model fits to the clinical malignant tumor data were bad, except for the shutter‐speed model. However, that overestimated TK parameters compared to the best‐fit 2‐compartment TK model, which predicted a significant blood volume and leaky capillaries (1 tracer compartment is insufficient, 2 are necessary). All models produced excellent fits to the clinical benign tumor data with little variation between parameter estimates (1 tracer compartment is sufficient).
Conclusion
The 2PX and shutter‐speed models were unable to estimate WX from the DCE‐MRI data. A good fit to malignant tumor data using the shutter‐speed model was not explained by WX, but the choice of an inappropriate TK model leading to distorted parameter estimates.
Objective
Antibiotic overuse contributes to antibiotic resistance and adverse consequences. Acute respiratory tract infections (RTIs) are the most common reason for antibiotic prescribing in primary ...care, but such infections often do not require antibiotics. We summarized and updated a previously performed systematic review of interventions to reduce inappropriate use of antibiotics for acute RTIs.
Methods
To update the review, we searched MEDLINE®, the Cochrane Library (until January 2018), and reference lists. Two reviewers selected the studies, extracted the study data, and assessed the quality and strength of evidence.
Results
Twenty-six interventions were evaluated in 95 mostly fair-quality studies. The following four interventions had moderate-strength evidence of improved/reduced antibiotic prescribing and low-strength evidence of no adverse consequences: parent education (21% reduction, no increase return visits), combined patient/clinician education (7% reduction, no change in complications/satisfaction), procalcitonin testing for adults with RTIs of the lower respiratory tract (12%–72% reduction, no increased adverse consequences), and electronic decision support systems (24%–47% improvement in appropriate prescribing, 5%–9% reduction, no increased complications).
Conclusions
The best evidence supports use of specific educational interventions, procalcitonin testing in adults, and electronic decision support to reduce inappropriate antibiotic prescribing for acute RTIs without causing adverse consequences.
AbstractPolarimetry of IGR J1401-4306, a long-period (12.7 h) eclipsing intermediate polar and remnant of Nova Scorpii 1437 AD, reveals periodic variations of optical circular polarization, ...confirming the system as the longest-period eclipsing intermediate polar known. This makes it an interesting system from an evolutionary perspective. The circular polarization is interpreted as optical cyclotron emission from an accreting magnetic white dwarf primary. Based on the polarimetry, we propose that it is a disc-fed intermediate polar. The detection of predominantly negative circular polarization is consistent with only one of the magnetic poles dominating the polarized emission, while the other is mostly obscured by the accretion disc.
PDF
