Implementation Science in Perioperative Care

There is a 17-year gap between the initial publication of scientific evidence and its uptake into widespread practice in health care. The field of implementation science (IS) emerged in the 1990s as an answer to this “evidence-to-practice gap.” In this article, we present an overview of implementation science, focusing on the application of IS principles to perioperative care. We describe opportunities for additional training and discuss strategies for funding and publishing IS work. The objective is to demonstrate how IS can improve perioperative patient care, while highlighting perioperative IS studies and identifying areas in need of additional investigation

Peculiarities in Velocity Dispersion and Surface Density Profiles of Star Clusters

Based on our recent work on tidal tails of star clusters (Kuepper et al. 2009) we investigate star clusters of a few 10^4 Msun by means of velocity dispersion profiles and surface density profiles. We use a comprehensive set of $N$-body computations of star clusters on various orbits within a realistic tidal field to study the evolution of these profiles with time, and ongoing cluster dissolution From the velocity dispersion profiles we find that the population of potential escapers, i.e. energetically unbound stars inside the Jacobi radius, dominates clusters at radii above about 50% of the Jacobi radius. Beyond 70% of the Jacobi radius nearly all stars are energetically unbound. The velocity dispersion therefore significantly deviates from the predictions of simple equilibrium models in this regime. We furthermore argue that for this reason this part of a cluster cannot be used to detect a dark matter halo or deviations from Newtonian gravity. By fitting templates to the about 10^4 computed surface density profiles we estimate the accuracy which can be achieved in reconstructing the Jacobi radius of a cluster in this way. We find that the template of King (1962) works well for extended clusters on nearly circular orbits, but shows significant flaws in the case of eccentric cluster orbits. This we fix by extending this template with 3 more free parameters. Our template can reconstruct the tidal radius over all fitted ranges with an accuracy of about 10%, and is especially useful in the case of cluster data with a wide radial coverage and for clusters showing significant extra-tidal stellar populations. No other template that we have tried can yield comparable results over this range of cluster conditions. All templates fail to reconstruct tidal parameters of concentrated clusters, however. (abridged)Comment: 23 pages, 13 figures, accepted for publication in MNRA

Systematic review and consensus definitions for the Standardised Endpoints in Perioperative Medicine initiative: patient-centred outcomes

BACKGROUND: Patient-centred outcomes are increasingly used in perioperative clinical trials. The Standardised Endpoints in Perioperative Medicine (StEP) initiative aims to define which measures should be used in future research to facilitate comparison between studies and to enable robust evidence synthesis. METHODS: A systematic review was conducted to create a longlist of patient satisfaction, health-related quality of life, functional status, patient well-being, and life-impact measures for consideration. A three-stage Delphi consensus process involving 89 international experts was then conducted in order to refine this list into a set of recommendations. RESULTS: The literature review yielded six patient-satisfaction measures, seven generic health-related quality-of-life measures, eight patient well-being measures, five functional-status measures, and five life-impact measures for consideration. The Delphi response rates were 92%, 87%, and 100% for Rounds 1, 2, and 3, respectively. Three additional measures were added during the Delphi process as a result of contributions from the StEP group members. Firm recommendations have been made about one health-related quality-of-life measure (EuroQol 5 Dimension, five-level version with visual analogue scale), one functional-status measure (WHO Disability Assessment Schedule version 2.0, 12-question version), and one life-impact measure (days alive and out of hospital at 30 days after surgery). Recommendations with caveats have been made about the Bauer patient-satisfaction measure and two life-impact measures (days alive and out of hospital at 1 yr after surgery, and discharge destination). CONCLUSIONS: Several patient-centred outcome measures have been recommended for use in future perioperative studies. We suggest that every clinical study should consider using at least one patient-centred outcome within a suite of endpoints

Detection of a multi-phase ISM at z=0.2212z=0.2212

We present sensitive Giant Metrewave Radio Telescope (GMRT) and high-resolution Arecibo HI 21-cm observations of the damped Lyman-$\alpha$ absorber (DLA) at $z=0.2212$ towards OI 363. The spectra are in excellent agreement and yield a spin temperature $T_s = 890 \pm 160$ K, far higher than $T_s$ values measured in local spirals, but similar to values obtained in the majority of DLAs (T_s \ga 1000 K). The high velocity resolution of the Arecibo spectra enables us to obtain estimates of physical conditions in the absorbing clouds by fitting multiple Gaussians to the absorption profile. The spectra are well fit by a three-component model with two narrow and one wide components, with temperatures ${T_{k_1}} = 308 \pm 24$ K, ${T_{k_2}} = 180 \pm 30$ K and ${T_{k_3}} = 7600 \pm 1250$ K, respectively. The last of these is in excellent agreement with the expected temperatures for the WNM ($5000 - 8000$ K). The mere fact that components are seen with lower temperatures than the estimated $T_s$ implies that the absorber must have a multi-phase medium. We use the measured 21-cm optical depth and the above estimates of the kinetic temperature to obtain the HI column density in the various components. The total column density in the narrow components is found to be \NHI (CNM) \le 1.9 \pm 0.25 \times 10^{20} cm, while that in the wide component is \NHI (WNM) \ge 1.26 \pm 0.49 \times 10^{21} cm. Thus, the WNM contains at least 75% of the total HI in the $z = 0.2212$ DLA, unlike our Galaxy, in which the CNM and WNM have equitable contributions; this accounts for the difference in the spin temperatures of the $z = 0.2212$ system and local spirals, suggesting that the DLA is probably a dwarf or LSB type galaxy (abridged).Comment: 8 pages, 2 figures. Accepted for publication in Astronomy and Astrophysics. Minor typos remove

Two-phase equilibrium and molecular hydrogen formation in damped Lyman-alpha systems

Molecular hydrogen is quite underabundant in damped Lyman-alpha systems at high redshift, when compared to the interstellar medium near the Sun. This has been interpreted as implying that the gas in damped Lyman-alpha systems is warm. like the nearby neutral intercloud medium, rather than cool, as in the clouds which give rise to most H I absorption in the Milky Way. Other lines of evidence suggest that the gas in damped Lyman-alpha systems -- in whole or part -- is actually cool; spectroscopy of neutral and ionized carbon, discussed here, shows that the damped Lyman-alpha systems observed at lower redshift z $$ 2.8 are warm (though not devoid of H2). To interpret the observations of carbon and hydrogen we constructed detailed numerical models of H2 formation under the conditions of two-phase thermal equilibrium, like those which account for conditions near the Sun, but with varying metallicity, dust-gas ratio, $etc$. We find that the low metallicity of damped Lyman-alpha systems is enough to suppress H2 formation by many orders of magnitude even in cool diffuse clouds, as long as the ambient optical/uv radiation field is not too small. For very low metallicity and under the most diffuse conditions, H2 formation will be dominated by slow gas-phase processes not involving grains, and a minimum molecular fraction in the range $10^{-8}-10^{-7}$ is expected.Comment: 13 pages, 7 figures; accepted 2002-04-30 by Astronomy and Astrophysic

The ProtecT trial: analysis of the patient cohort, baseline risk stratification and disease progression.

OBJECTIVE: To test the hypothesis that the baseline clinico-pathological features of the men with localized prostate cancer (PCa) included in the ProtecT (Prostate Testing for Cancer and Treatment) trial who progressed (n = 198) at a 10-year median follow-up were different from those of men with stable disease (n = 1409). PATIENTS AND METHODS: We stratified the study participants at baseline according to risk of progression using clinical disease stage, pathological grade and PSA level, using Cox proportional hazard models. RESULTS: The findings showed that 34% of participants (n = 505) had intermediate- or high-risk PCa, and 66% (n = 973) had low-risk PCa. Of 198 participants who progressed, 101 (51%) had baseline International Society of Urological Pathology Grade Group 1, 59 (30%) Grade Group 2, and 38 (19%) Grade Group 3 PCa, compared with 79%, 17% and 5%, respectively, for 1409 participants without progression (P < 0.001). In participants with progression, 38% and 62% had baseline low- and intermediate-/high-risk disease, compared with 69% and 31% of participants with stable disease (P < 0.001). Treatment received, age (65-69 vs 50-64 years), PSA level, Grade Group, clinical stage, risk group, number of positive cores, tumour length and perineural invasion were associated with time to progression (P ≤ 0.005). Men progressing after surgery (n = 19) were more likely to have a higher Grade Group and pathological stage at surgery, larger tumours, lymph node involvement and positive margins. CONCLUSIONS: We demonstrate that one-third of the ProtecT cohort consists of people with intermediate-/high-risk disease, and the outcomes data at an average of 10 years' follow-up are generalizable beyond men with low-risk PCa

Reconciling the local galaxy population with damped Ly-alpha cross sections and metal abundances

A comprehensive analysis of 355 high-quality WSRT HI 21-cm line maps of nearby galaxies shows that the properties and incident rate of Damped Lyman-alpha (DLA) absorption systems observed in the spectra of high redshift QSOs are in good agreement with DLAs originating in gas disks of galaxies like those in the z~0 population. Comparison of low-z DLA statistics with the HI incidence rate and column density distribution f(N) for the local galaxy sample shows no evidence for evolution in the integral "cross section density" below z~1.5, implying that there is no need for a hidden population of galaxies or HI clouds to contribute significantly to the DLA cross section. Compared with z~4, our data indicates evolution of a factor of two in the comoving density along a line of sight. We find that dN/dz(z=0)=0.045 +/- 0.006. The idea that the local galaxy population can explain the DLAs is further strengthened by comparing the properties of DLAs and DLA galaxies with the expectations based on our analysis of local galaxies. The distribution of luminosities of DLA host galaxies, and of impact parameters between QSOs and the centres of DLA galaxies, are in good agreement with what is expected from local galaxies. Approximately 87% of low z DLA galaxies are expected to be fainter than L* and 37 per cent have impact parameters less than 1'' at z=0.5. The analysis shows that some host galaxies with very low impact parameters and low luminosities are expected to be missed in optical follow up surveys. The well-known metallicity-luminosity relation in galaxies, in combination with metallicity gradients in galaxy disks, cause the expected median metallicity of low redshift DLAs to be low (~1/7 solar), which is also in good agreement with observations of low z DLAs. (Abridged)Comment: 22 pages, 22 figures. Accepted for publication in MNRAS. Fixed typo

Handoffs and Transitions in Critical Care (HATRICC): Protocol for a Mixed Methods Study of Operating Room to Intensive Care Unit Handoffs

Background: Operating room to intensive care unit handoffs are high-risk events for critically ill patients. Studies in selected patient populations show that standardizing operating room to intensive care unit handoffs improves information exchange and decreases errors. To adapt these findings to mixed surgical populations, we propose to study the implementation of a standardized operating room to intensive care unit handoff process in two intensive care units currently without an existing standard process. Methods/Design: The Handoffs and Transitions in Critical Care (HATRICC) study is a hybrid effectiveness- implementation trial of operating room to intensive care unit handoffs. We will use mixed methods to conduct a needs assessment of the current handoff process, adapt published handoff processes, and implement a new standardized handoff process in two academic intensive care units. Needs assessment: We will use non-participant observation to observe the current handoff process. Focus groups, interviews, and surveys of clinicians will elicit participants’ impressions about the current process. Adaptation and implementation: We will adapt published standardized handoff processes using the needs assessment findings. We will use small group simulation to test the new process’ feasibility. After simulation, we will incorporate the new handoff process into the clinical work of all providers in the study units. Evaluation: Using the same methods employed in the needs assessment phase, we will evaluate use of the new handoff process. Data analysis: The primary effectiveness outcome is the number of information omissions per handoff episode as compared to the pre-intervention period. Additional intervention outcomes include patient intensive care unit length of stay and intensive care unit mortality. The primary implementation outcome is acceptability of the new process. Additional implementation outcomes include feasibility, fidelity and sustainability. Discussion: The HATRICC study will examine the effectiveness and implementation of a standardized operating room to intensive care unit handoff process. Findings from this study have the potential to improve healthcare communication and outcomes for critically ill patients. Trial registration: ClinicalTrials.gov identifier: NCT02267174. Date of registration October 16, 2014

Novel Isoprene-Degrading Proteobacteria From Soil and Leaves Identified by Cultivation and Metagenomics Analysis of Stable Isotope Probing Experiments

Isoprene is a climate-active gas and one of the most abundant biogenic volatile organic compounds (BVOC) released into the atmosphere. In the terrestrial environment, plants are the primary producers of isoprene, releasing between 500 and 750 million tons per year to protect themselves from environmental stresses such as direct radiation, heat, and reactive oxygen species. While many studies have explored isoprene production, relatively little is known about consumption of isoprene by microbes and the most well-characterized isoprene degrader is a Rhodococcus strain isolated from freshwater sediment. In order to identify a wider range of bacterial isoprene-degraders in the environment, DNA stable isotope probing (DNA-SIP) with 13C-labeled isoprene was used to identify active isoprene degraders associated with soil in the vicinity of a willow tree. Retrieval by PCR of 16S rRNA genes from the 13C-labeled DNA revealed an active isoprene-degrading bacterial community dominated by Proteobacteria, together with a minor portion of Actinobacteria, mainly of the genus Rhodococcus. Metagenome sequencing of 13C-labeled DNA from SIP experiments enabled analysis of genes encoding key enzymes of isoprene metabolism from novel isoprene degraders. Informed by these DNA-SIP experiments and working with leaves and soil from the vicinity of tree species known to produce high amounts of isoprene, four novel isoprene-degrading strains of the genera Nocardioides, Ramlibacter, Variovorax and Sphingopyxis, along with strains of Rhodococcus and Gordonia, genera that are known to contain isoprene-degrading strains, were isolated. The use of lower concentrations of isoprene during enrichment experiments has revealed active Gram-negative isoprene-degrading bacteria associated with isoprene-emitting trees. Analysis of isoprene-degradation genes from these new isolates provided a more robust phylogenetic framework for analysis of isoA, encoding the α-subunit of the isoprene monooxygenase, a key molecular marker gene for cultivation-independent studies on isoprene degradation in the terrestrial environment