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Rapid Response of an Academic Surgical Department to the COVID-19 Pandemic: Implications for Patients, Surgeons, and the Community.
BackgroundAs the coronavirus disease 2019 (COVID-19) pandemic continues to spread, swift actions and preparation are critical for ensuring the best outcomes for patients and providers. We aim to describe our hospital and Department of Surgery's experience in preparing for the COVID-19 pandemic and caring for surgical patients during this unprecedented time.Study designThis is a descriptive study outlining the strategy of a single academic health system for addressing the following 4 critical issues facing surgical departments during the COVID-19 pandemic: developing a cohesive leadership team and system for frequent communication throughout the department; ensuring adequate hospital capacity to care for an anticipated influx of COVID-19 patients; safeguarding supplies of blood products and personal protective equipment to protect patients and providers; and preparing for an unstable workforce due to illness and competing personal priorities, such as childcare.ResultsThrough collaborative efforts within the Department of Surgery and hospital, we provided concise and regular communication, reduced operating room volume by 80%, secured a 4-week supply of personal protective equipment, and created reduced staffing protocols with back-up staffing plans.ConclusionsBy developing an enabling infrastructure, a department can nimbly respond to crises like COVID-19 by promoting trust among colleagues and emphasizing an unwavering commitment to excellent patient care. Sharing principles and practical applications of these changes is important to optimize responses across the country and the world
Blood Transfusion Errors within a Health System: A Review of Root Cause Analyses
IntroductionBlood transfusions are lifesaving treatments which require critical attention to processes and details. If processes are not followed, grievous errors can lead to sentinel events. A review of investigations completed due to reported events will show the error trends associated with systems used throughout the blood transfusion process.
MethodsThis study employed root cause analyses (RCAs) within the Veterans Health Administration (VHA) to review the events leading to blood transfusion errors. Data was pulled from the RCA databases within the VA National Center for Patient Safety. The time frame was October 2014 to August 2019. A total of 53 RCAs and aggregated reviews were included in the study. These were reviewed for common themes and gaps present within processes.
ResultsThe most common events fell within the categories of incorrect or delayed blood orders, incorrect or lack of patient identification, and wrong blood given. The RCA for each event was reviewed and studied. The RCAs had a crossover of multiple causes; lack of a formal process, communication barriers, and technology barriers were the most frequent.
ConclusionThese RCAs express great variation between VHA facilities, such as process created, number of staff reports, and number of RCAs completed. Lack of standard practices nationwide, training barriers, and technology barriers may explain the variation of transfusion errors throughout the VHA. This study brings to light questions about standardization of transfusion protocols. Future study regarding such standardization is necessary to determine its plausibility
The HIV Care Continuum among Female Sex Workers: A Key Population in Lilongwe, Malawi
ObjectiveThe HIV care continuum among female sex workers (FSW), a key population, has not been well characterized, especially within the generalized epidemics of sub-Saharan Africa. This was the first study to characterize the HIV care continuum among FSW in Lilongwe, Malawi.MethodsFrom July through September 2014, we used venue-based sampling to enroll 200 adult FSW in Lilongwe, Malawi into a cross-sectional evaluation assessing HIV care continuum outcomes. Seropositive FSW, identified using HIV rapid testing, received rapid CD4 counts in addition to viral loads using dried blood spots. We calculated proportions of HIV-infected FSW who had history of care, were on ART, and had suppressed viral load and we used Poisson regression to estimate the associations of demographic characteristics and transmission risk behaviors with each outcome.ResultsHIV seroprevalence was 69% (n = 138). Among all FSW the median age was 24 years (IQR: 22â28). Among the 20% who were newly diagnosed and reported previously testing negative, the median time since last HIV test was 11 months (interquartile range: 3â17). The majority (69%) of HIV-infected FSW had a history of HIV care, 52% reported current ART use, and 45% were virally suppressed. Of the FSW who reported current ART use, 86% were virally suppressed. Transmission risk behaviors were not associated with continuum outcomes.ConclusionsFSW in Lilongwe were predominately young and have a high HIV prevalence. Only half of HIV-infected FSW reported current ART use, but the majority of those on ART were virally suppressed. To reduce ongoing transmission and improve health outcomes, increased HIV testing, care engagement, and ART coverage is urgently needed among FSW. Universal testing and treatment strategies for all FSW in Malawi must be strongly considered
Very Small Array observations of the Sunyaev-Zel'dovich effect in nearby galaxy clusters
We present VSA observations (~34GHz) on scales ~20 arcmin towards a complete,
X-ray-flux-limited sample of seven clusters at redshift z<0.1. Four have
significant SZ detections in the presence of CMB primordial anisotropy. We use
a bayesian MCMC method for inference from the VSA data, with X-ray priors on
cluster positions and temperatures, and radio priors on sources. We make
assumptions of beta-model gas distributions and of hydrostatic equilibrium, to
evaluate probability densities for the gas mass and total mass out to r_200.
Our combined estimate of the gas fraction is 0.08^{+0.06}_{-0.04}h^{-1} The
random errors are poor (note that the errors are higher than would have been
obtained with the usual chi-squared method) but the control of bias is good. We
have described the MCMC analysis method specifically in terms of SZ but hope
the description will be of more general use. We find that the effects of
primordial CMB contamination tend to be similar in the estimates of both the
gas mass and total mass over our narrow range of angular scales, so that there
is little effect of primordials on the gas fraction determination. Using our
total mass estimates we find a normalisation of the mass-temperature relation
based on the profiles from the VSA cluster pressure maps that is in good
agreement with recent M-T determinations from X-ray cluster measurements.Comment: Replaces earlier version. 16 pages, 5 figures, LaTeX. Minor revisions
to content, accepted by MNRAS for publicatio
High sensitivity measurements of the CMB power spectrum with the extended Very Small Array
We present deep Ka-band ( GHz) observations of the CMB made
with the extended Very Small Array (VSA). This configuration produces a
naturally weighted synthesized FWHM beamwidth of arcmin which covers
an -range of 300 to 1500. On these scales, foreground extragalactic
sources can be a major source of contamination to the CMB anisotropy. This
problem has been alleviated by identifying sources at 15 GHz with the Ryle
Telescope and then monitoring these sources at 33 GHz using a single baseline
interferometer co-located with the VSA. Sources with flux densities \gtsim 20
mJy at 33 GHz are subtracted from the data. In addition, we calculate a
statistical correction for the small residual contribution from weaker sources
that are below the detection limit of the survey.
The CMB power spectrum corrected for Galactic foregrounds and extragalactic
point sources is presented. A total -range of 150-1500 is achieved by
combining the complete extended array data with earlier VSA data in a compact
configuration. Our resolution of allows the first 3
acoustic peaks to be clearly delineated. The is achieved by using mosaiced
observations in 7 regions covering a total area of 82 sq. degrees. There is
good agreement with WMAP data up to where WMAP data run out of
resolution. For higher -values out to , the agreement in
power spectrum amplitudes with other experiments is also very good despite
differences in frequency and observing technique.Comment: 16 pages. Accepted in MNRAS (minor revisions
Searching for non-Gaussianity in the VSA data
We have tested Very Small Array (VSA) observations of three regions of sky
for the presence of non-Gaussianity, using high-order cumulants, Minkowski
functionals, a wavelet-based test and a Bayesian joint power
spectrum/non-Gaussianity analysis. We find the data from two regions to be
consistent with Gaussianity. In the third region, we obtain a 96.7% detection
of non-Gaussianity using the wavelet test. We perform simulations to
characterise the tests, and conclude that this is consistent with expected
residual point source contamination. There is therefore no evidence that this
detection is of cosmological origin. Our simulations show that the tests would
be sensitive to any residual point sources above the data's source subtraction
level of 20 mJy. The tests are also sensitive to cosmic string networks at an
rms fluctuation level of (i.e. equivalent to the best-fit observed
value). They are not sensitive to string-induced fluctuations if an equal rms
of Gaussian CDM fluctuations is added, thereby reducing the fluctuations due to
the strings network to rms . We especially highlight the usefulness
of non-Gaussianity testing in eliminating systematic effects from our data.Comment: Minor corrections; accepted for publication to MNRA
Estimating the bispectrum of the Very Small Array data
We estimate the bispectrum of the Very Small Array data from the compact and
extended configuration observations released in December 2002, and compare our
results to those obtained from Gaussian simulations. There is a slight excess
of large bispectrum values for two individual fields, but this does not appear
when the fields are combined. Given our expected level of residual point
sources, we do not expect these to be the source of the discrepancy. Using the
compact configuration data, we put an upper limit of 5400 on the value of f_NL,
the non-linear coupling parameter, at 95 per cent confidence. We test our
bispectrum estimator using non-Gaussian simulations with a known bispectrum,
and recover the input values.Comment: 17 pages, 16 figures, replaced with version accepted by MNRAS.
Primordial bispectrum recalculated and figure 11 change
CMB observations from the CBI and VSA: A comparison of coincident maps and parameter estimation methods
We present coincident observations of the Cosmic Microwave Background (CMB)
from the Very Small Array (VSA) and Cosmic Background Imager (CBI) telescopes.
The consistency of the full datasets is tested in the map plane and the Fourier
plane, prior to the usual compression of CMB data into flat bandpowers. Of the
three mosaics observed by each group, two are found to be in excellent
agreement. In the third mosaic, there is a 2 sigma discrepancy between the
correlation of the data and the level expected from Monte Carlo simulations.
This is shown to be consistent with increased phase calibration errors on VSA
data during summer observations. We also consider the parameter estimation
method of each group. The key difference is the use of the variance window
function in place of the bandpower window function, an approximation used by
the VSA group. A re-evaluation of the VSA parameter estimates, using bandpower
windows, shows that the two methods yield consistent results.Comment: 10 pages, 6 figures. Final version. Accepted for publication in MNRA
Cosmological parameter estimation using Very Small Array data out to l=1500
We estimate cosmological parameters using data obtained by the Very Small
Array (VSA) in its extended configuration, in conjunction with a variety of
other CMB data and external priors. Within the flat CDM model, we find
that the inclusion of high resolution data from the VSA modifies the limits on
the cosmological parameters as compared to those suggested by WMAP alone, while
still remaining compatible with their estimates. We find that , , , , and
for WMAP and VSA when no external prior is
included.On extending the model to include a running spectral index of density
fluctuations, we find that the inclusion of VSA data leads to a negative
running at a level of more than 95% confidence (),
something which is not significantly changed by the inclusion of a stringent
prior on the Hubble constant. Inclusion of prior information from the 2dF
galaxy redshift survey reduces the significance of the result by constraining
the value of . We discuss the veracity of this result in the
context of various systematic effects and also a broken spectral index model.
We also constrain the fraction of neutrinos and find that at
95% confidence which corresponds to when all neutrino
masses are the equal. Finally, we consider the global best fit within a general
cosmological model with 12 parameters and find consistency with other analyses
available in the literature. The evidence for is only marginal
within this model
Human papillomavirus infection in âyoungâ versus âoldâ patients with squamous cell carcinoma of the head and neck
Background Human papillomavirus (HPV) represents a potential risk factor for squamous cell cancer of the head and neck (SCCHN). We evaluated the prevalence of HPV DNA in patients with SCCHN diagnosed at the University of Michigan from 1994â1996. Methods Patients were stratified by age at diagnosis as âyoungâ (50 years; median, 66). Fourteen âyoungâ and 14 âoldâ were matched for tumor site, and 4 additional âoldâ patients were included. Specimens were analyzed by polymerase chain reaction for HPV DNA using 2 sets of consensus primers. HPV sequences were confirmed by Southern blot hybridization and typed with type-specific probes. Results Overall, 15 of 32 (46.9%) samples contained HPV sequences. HPV 16 was detected in 9 of 15 (60%), HPV-18 in 1 of 15 (6.6%), and 5 of 15 (33.3%) remained untyped by multiple methods. When stratified, 7 of 14 (50%) âyoungâ were HPV-positive compared with 8 of 18 (44.4%) âoldâ ( p = .76). Survival in patients with HPV-positive SCCHN was significantly longer than that for HPV-negative patients. Conclusions The incidence of HPV in âyoungâ versus âoldâ is not significantly different, suggesting similar roles for both groups. Patients with HPV-positive tumors may have a survival advantage relative to patients with HPV-negative tumors. © 2000 John Wiley & Sons, Inc. Head Neck 22: 649â657, 2000.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/35115/1/2_ftp.pd
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