347 research outputs found
Tracheotomy does not affect reducing sedation requirements of patients in intensive care – a retrospective study
INTRODUCTION: Translaryngeal intubated and ventilated patients often need sedation to treat anxiety, agitation and/or pain. Current opinion is that tracheotomy reduces sedation requirements. We determined sedation needs before and after tracheotomy of intubated and mechanically ventilated patients. METHODS: We performed a retrospective analysis of the use of morphine, midazolam and propofol in patients before and after tracheotomy. RESULTS: Of 1,788 patients admitted to our intensive care unit during the study period, 129 (7%) were tracheotomized. After the exclusion of patients who received a tracheotomy before or at the day of admittance, 117 patients were left for analysis. The daily dose (DD; the amount of sedatives for each day) divided by the mean daily dose (MDD; the mean amount of sedatives per day for the study period) in the week before and the week after tracheotomy was 1.07 ± 0.93 DD/MDD versus 0.30 ± 0.65 for morphine, 0.84 ± 1.03 versus 0.11 ± 0.46 for midazolam, and 0.62 ± 1.05 versus 0.15 ± 0.45 for propofol (p < 0.01). However, when we focused on a shorter time interval (two days before and after tracheotomy), there were no differences in prescribed doses of morphine and midazolam. Studying the course in DD/MDD from seven days before the placement of tracheotomy, we found a significant decline in dosage. From day -7 to day -1, morphine dosage (DD/MDD) declined by 3.34 (95% confidence interval -1.61 to -6.24), midazolam dosage by 2.95 (-1.49 to -5.29) and propofol dosage by 1.05 (-0.41 to -2.01). After tracheotomy, no further decrease in DD/MDD was observed and the dosage remained stable for all sedatives. Patients in the non-surgical and acute surgical groups received higher dosages of midazolam than patients in the elective surgical group. Time until tracheotomy did not influence sedation requirements. In addition, there was no significant difference in sedation between different patient groups. CONCLUSION: In our intensive care unit, sedation requirements were not further reduced after tracheotomy. Sedation requirements were already sharply declining before tracheotomy was performed
Nematic Films and Radially Anisotropic Delaunay Surfaces
We develop a theory of axisymmetric surfaces minimizing a combination of
surface tension and nematic elastic energies which may be suitable for
describing simple film and bubble shapes. As a function of the elastic constant
and the applied tension on the bubbles, we find the analogues of the unduloid,
sphere, and nodoid in addition to other new surfaces.Comment: 15 pages, 18 figure
Diagnostic accuracy of follow-up tests for detecting colorectal cancer recurrences in primary care:A systematic review and meta-analysis
Introduction
Traditionally, follow-up of colorectal cancer (CRC) is performed in secondary care. In new models of care, the screening part care could be replaced to primary care. We aimed to synthesise evidence on the diagnostic accuracy of commonly used screeners in CRC follow-up applicable in primary care: carcinoembryonic antigen (CEA), ultrasound and physical examination.
Methods
Medline, EMBASE, Cochrane Trial Register and Web of Science databases were systematically searched. Studies were included if they provided sufficient data for a 2 × 2 contingency tables. QUADAS-2 was used to assess methodological quality. We performed bivariate random effects meta-analysis, generated a hypothetical cohort, and reported sensitivity and specificity.
Results
We included 12 studies (n = 3223, median recurrence rate 19.6%). Pooled estimates showed a sensitivity for CEA (≤ 5 μg/l) of 59% [47%–70%] and a specificity of 89% [80%–95%]. Only few studies reported sensitivities and specificities for ultrasound (36–70% and 97–100%, respectively) and clinical examination (23% and 27%, respectively).
Conclusion
In practice, GPs could perform CEA screening. Radiological examination in a hospital setting should remain part of the surveillance strategy. Personalised algorithms accounting for recurrence risk and changes of CEA-values over time might add to the diagnostic value of CEA in primary care
Layered ferromagnet-superconductor structures: the state and proximity effects
We investigate clean mutilayered structures of the SFS and SFSFS type, (where
the S layer is intrinsically superconducting and the F layer is ferromagnetic)
through numerical solution of the self-consistent Bogoliubov-de Gennes
equations for these systems. We obtain results for the pair amplitude, the
local density of states, and the local magnetic moment. We find that as a
function of the thickness of the magnetic layers separating adjacent
superconductors, the ground state energy varies periodically between two stable
states. The first state is an ordinary "0-state", in which the order parameter
has a phase difference of zero between consecutive S layers, and the second is
a "-state", where the sign alternates, corresponding to a phase difference
of between adjacent S layers. This behavior can be understood from simple
arguments. The density of states and the local magnetic moment reflect also
this periodicity.Comment: 12 pages, 10 Figure
Recommended from our members
Association of endocrine disrupting chemicals exposure with human chorionic gonadotropin concentrations in pregnancy
Data availability:
The authors do not have permission to share data.Supplementary material is available online at https://www.sciencedirect.com/science/article/pii/S0160412023003641#s0105 .Copyright © 2023 The Author(s). Background:
Human chorionic gonadotropin (hCG) is produced by the placenta and plays an essential role in the maintenance of pregnancy. Endocrine disrupting chemicals (EDCs) have the potential to interfere with functions related to the production and secretion of hCG; however associations between exposure to EDCs and hCG concentrations in humans remain to be elucidated.
Objectives:
To investigate the association of urinary, serum and plasma concentrations of EDCs during pregnancy with serum hCG concentrations.
Methods:
We utilized data form the Swedish Environmental Longitudinal, Mother and child, Asthma and allergy (SELMA) study. We investigated the association of 26 EDCs measured in early pregnancy urine or blood with serum hCG concentrations using multi-variable adjusted linear regression models per EDC and Weighted Quantile Sum (WQS) regression with repeated holdout validation for the EDCs mixture.
Results:
In 2,039 included women, higher exposure to bisphenol A was associated with lower hCG (beta [95% CI]: −0.06 [−0.11 to −0.002]) while higher triclosan exposure was associated with a higher hCG (0.02 [0.003 to 0.04]). Higher exposure to several phthalates, including mono-ethyl and mono-butyl phthalates (MEP and MBP) as well as metabolites of di-2-ethylhexyl phthalate (DEHP) was associated with a lower hCG (beta [95% CI] for sum of DEHP metabolites: −0.13 [−0.19 to −0.07]). Likewise, higher exposure to several polychlorinated biphenyls (PCBs) was associated with a lower hCG. In the WQS regression, each quartile increase in the EDCs mixture was associated with −0.27 lower hCG (95% CI: −0.34 to −0.19).
Discussion:
Higher exposure to several EDCs during pregnancy was associated with a lower hCG; and despite the small effect sizes, still indicating that the exposure may negatively affect production or secretion of hCG by the placenta. Our results provide the impetus for future experimental studies to investigate the placenta as a target organ for adverse effects of EDCs.This project has been supported by the Exchange in Endocrinology Expertise (3E) program of the European Union of Medical Specialists (UEMS), Section and Board of Endocrinology and the ATHENA project, funded under the European Union’s Horizon 2020 Programme for research, technological development and demonstration, grant agreement no. 825161. The SELMA study was funded by grants from the Swedish Research Council (Formas). The sample analysis were supported by Region Skåne and the Medical Faculty at Lund University, Sweden
Regularity of harmonic discs in spaces with quadratic isoperimetric inequality
We study harmonic and quasi-harmonic discs in metric spaces admitting a uniformly local quadratic isoperimetric inequality for curves. The class of such metric spaces includes compact Lipschitz manifolds, metric spaces with upper or lower curvature bounds in the sense of Alexandrov, some sub-Riemannian manifolds, and many more. In this setting, we prove local Hölder continuity and continuity up to the boundary of harmonic and quasi-harmonic discs
Intra-cluster correlations from the CLustered OUtcome Dataset bank to inform the design of longitudinal cluster trials.
BACKGROUND: Sample size calculations for longitudinal cluster randomised trials, such as crossover and stepped-wedge trials, require estimates of the assumed correlation structure. This includes both within-period intra-cluster correlations, which importantly differ from conventional intra-cluster correlations by their dependence on period, and also cluster autocorrelation coefficients to model correlation decay. There are limited resources to inform these estimates. In this article, we provide a repository of correlation estimates from a bank of real-world clustered datasets. These are provided under several assumed correlation structures, namely exchangeable, block-exchangeable and discrete-time decay correlation structures. METHODS: Longitudinal studies with clustered outcomes were collected to form the CLustered OUtcome Dataset bank. Forty-four available continuous outcomes from 29 datasets were obtained and analysed using each correlation structure. Patterns of within-period intra-cluster correlation coefficient and cluster autocorrelation coefficients were explored by study characteristics. RESULTS: The median within-period intra-cluster correlation coefficient for the discrete-time decay model was 0.05 (interquartile range: 0.02-0.09) with a median cluster autocorrelation of 0.73 (interquartile range: 0.19-0.91). The within-period intra-cluster correlation coefficients were similar for the exchangeable, block-exchangeable and discrete-time decay correlation structures. Within-period intra-cluster correlation coefficients and cluster autocorrelations were found to vary with the number of participants per cluster-period, the period-length, type of cluster (primary care, secondary care, community or school) and country income status (high-income country or low- and middle-income country). The within-period intra-cluster correlation coefficients tended to decrease with increasing period-length and slightly decrease with increasing cluster-period sizes, while the cluster autocorrelations tended to move closer to 1 with increasing cluster-period size. Using the CLustered OUtcome Dataset bank, an RShiny app has been developed for determining plausible values of correlation coefficients for use in sample size calculations. DISCUSSION: This study provides a repository of intra-cluster correlations and cluster autocorrelations for longitudinal cluster trials. This can help inform sample size calculations for future longitudinal cluster randomised trials
Preferred reporting items for journal and conference abstracts of systematic reviews and meta-analyses of diagnostic test accuracy studies (PRISMA-DTA for Abstracts):checklist, explanation, and elaboration
For many users of the biomedical literature, abstracts may be the only source of information about a study. Hence, abstracts should allow readers to evaluate the objectives, key design features, and main results of the study. Several evaluations have shown deficiencies in the reporting of journal and conference abstracts across study designs and research fields, including systematic reviews of diagnostic test accuracy studies. Incomplete reporting compromises the value of research to key stakeholders. The authors of this article have developed a 12 item checklist of preferred reporting items for journal and conference abstracts of systematic reviews and meta-analyses of diagnostic test accuracy studies (PRISMA-DTA for Abstracts). This article presents the checklist, examples of complete reporting, and explanations for each item of PRISMA-DTA for Abstracts
Multivariable Prediction Model for Biochemical Response to First-Generation Somatostatin Receptor Ligands in Acromegaly
CONTEXT: First-generation somatostatin receptor ligands (fg-SRLs) represent the mainstay of medical therapy for acromegaly, but they provide biochemical control of disease in only a subset of patients. Various pretreatment biomarkers might affect biochemical response to fg-SRLs. OBJECTIVE: To identify clinical predictors of the biochemical response to fg-SRLs monotherapy defined as biochemical response (insulin-like growth factor (IGF)-1 ≤ 1.3 × ULN (upper limit of normal)), partial response (>20% relative IGF-1 reduction without normalization), and nonresponse (≤20% relative IGF-1 reduction), and IGF-1 reduction. DESIGN: Retrospective multicenter study. SETTING: Eight participating European centers. METHODS: We performed a meta-analysis of participant data from 2 cohorts (Rotterdam and Liège acromegaly survey, 622 out of 3520 patients). Multivariable regression models were used to identify predictors of biochemical response to fg-SRL monotherapy. RESULTS: Lower IGF-1 concentration at baseline (odds ratio (OR) = 0.82, 95% confidence interval (CI) 0.72-0.95 IGF-1 ULN, P = .0073) and lower bodyweight (OR = 0.99, 95% CI 0.98-0.99 kg, P = .038) were associated with biochemical response. Higher IGF-1 concentration at baseline (OR = 1.40, (1.19-1.65) IGF-1 ULN, P ≤ .0001), the presence of type 2 diabetes (oral medication OR = 2.48, (1.43-4.29), P = .0013; insulin therapy OR = 2.65, (1.02-6.70), P = .045), and higher bodyweight (OR = 1.02, (1.01-1.04) kg, P = .0023) were associated with achieving partial response. Younger patients at diagnosis are more likely to achieve nonresponse (OR = 0.96, (0.94-0.99) year, P = .0070). Baseline IGF-1 and growth hormo
- …