Line days as a determinant of central line-associated bloodstream infections in pediatric patients with tunneled femoral peripherally inserted central catheters.

BACKGROUND: Ultrasound (US)-guided tunneled femoral peripherally inserted central catheters (PICCs) are a safe central venous access option in infants and neonates. Studies have shown, however, that femoral central venous access has the potential for high central line-associated bloodstream infection (CLABSI) rates with a significant increase in risk around line day 30, though no studies have evaluated these risks exclusively for tunneled femoral PICCs. OBJECTIVE: The primary purpose of this study was to evaluate the relationship between line duration and the risk of CLABSI in tunneled femoral PICCs in children. MATERIALS AND METHODS: Four hundred forty-five patients (196 females, 249 males; median age: 49.4 days; median weight: 3.7 kg) who underwent 573 tunneled femoral PICC placements or exchanges from Jan. 1, 2017, to Jan. 31, 2020, were included in the study. All tunneled femoral PICCs were placed using US technique and catheter specifications, including catheter size (French) and length (cm), were retrieved from the electronic medical record. The location of the PICC placement, the number of lumens, the laterality of placement, and the patient's age and weight were also recorded. Only non-mucosal barrier injury CLABSIs, according to the Centers for Disease Control and Prevention (CDC) definitions, were counted as CLABSI for this study. The number of central line days until a CLABSI event was analyzed with an accelerated failure time model using the exponential, Weibull, and log-normal distributions to determine the probability of a CLABSI over time, taking into consideration the recorded covariates. RESULTS: Tunneled femoral PICC placements accounted for 14,855 line days, during which 20 non-mucosal barrier injury CLABSIs (CLABSI rate of 1.35 per 1,000 line days) occurred during the study period. The highest CLABSI rate occurred in PICCs placed in the neonatal intensive care unit (NICU) at 2.01 per 1,000 line days and the lowest occurred in PICCs placed in interventional radiology at 0.26 per 1,000 line days. Overall, PICCs placed outside of interventional radiology had a CLABSI rate of 1.72 per 1,000 line days. The CLABSI rate during the first 30 days a line was in situ was lower than the rate after 30 days (0.51 per 1,000 line days vs. 3.06 per 1,000 line days, respectively). Statistical modeling and hazard estimation using the Akaike information criterion corrected for small sample size (AICc)-average of log-normal, Weibull and exponential distributions demonstrate the daily risk of CLABSI rapidly increases from day 1 to day 30, with the risk remaining high for the duration of line days. CONCLUSION: While tunneled femoral PICCs are a relatively safe and effective central venous access alternative, the rate of CLABSI appears to rapidly increase with increasing line days until around day 30 and then remains high thereafter.

The case for information fiduciaries: The implementation of a data ethics checklist at Seattle Children's Hospital.

There is little debate about the importance of ethics in health care, and clearly defined rules, regulations, and oaths help ensure patients' trust in the care they receive. However, standards are not as well established for the data professions within health care, even though the responsibility to treat patients in an ethical way extends to the data collected about them. Increasingly, data scientists, analysts, and engineers are becoming fiduciarily responsible for patient safety, treatment, and outcomes, and will require training and tools to meet this responsibility. We developed a data ethics checklist that enables users to consider the possible ethical issues that arise from the development and use of data products. The combination of ethics training for data professionals, a data ethics checklist as part of project management, and a data ethics committee holds potential for providing a framework to initiate dialogues about data ethics and can serve as an ethical touchstone for rapid use within typical analytic workflows, and we recommend the use of this or equivalent tools in deploying new data products in hospitals.

Forehead location and large segmental pattern of facial port-wine stains predict risk of Sturge-Weber syndrome.

BACKGROUND: Children with forehead port-wine stains (PWSs) are at risk of Sturge-Weber syndrome (SWS). However, most will not develop neurologic manifestations. OBJECTIVE: To identify children at greatest risk of SWS. METHOD: In this retrospective cohort study of children with a forehead PWS, PWSs were classified as "large segmental" (half or more of a contiguous area of the hemiforehead or median pattern) or "trace/small segmental" (less than half of the hemiforehead). The outcome measure was a diagnosis of SWS. RESULTS: Ninety-six children had a forehead PWS. Fifty-one had a large segmental PWS, and 45 had a trace/small segmental PWS. All 21 children with SWS had large segmental forehead PWSs. Large segmental forehead PWSs had a higher specificity (0.71 vs 0.27, P < .0001) and a higher positive predictive value (0.41 vs 0.22, P < .0001) for SWS than any forehead involvement by a PWS. LIMITATIONS: Retrospective study at a referral center. CONCLUSION: Children with large segmental forehead PWSs are at highest risk of SWS.

Eutrophication forcings on a peri-urban lake ecosystem: Context for integrated watershed to airshed management.

Peri-urban lakes increasingly experience intensified anthropogenic impacts as watershed uses and developments increase. Cultus Lake is an oligo-mesotrophic, peri-urban lake near Vancouver, British Columbia, Canada that experiences significant seasonal tourism, anthropogenic nutrient loadings, and associated cultural eutrophication. Left unabated, these cumulative stresses threaten the critical habitat and persistence of two endemic species at risk (Coastrange Sculpin, Cultus population; Cultus Lake sockeye salmon) and diverse lake-derived ecosystem services. We constructed water and nutrient budgets for the Cultus Lake watershed to identify and quantify major sources and loadings of nitrogen (N) and phosphorus (P). A steady-state water quality model, calibrated against current loadings and limnological data, was used to reconstruct the historic lake trophic status and explore limnological changes in response to realistic development and mitigation scenarios. Significant local P loadings to Cultus Lake arise from septic leaching (19%) and migratory gull guano deposition (22%). Watershed runoff contributes the majority of total P (53%) and N (73%) loads to Cultus Lake, with substantial local N contributions arising from the agricultural Columbia Valley (41% of total N load). However, we estimate that up to 66% of N and 70% of P in watershed runoff is ultimately sourced via deposition from the nutrient-contaminated regional airshed, with direct atmospheric deposition on the lake surface contributing an additional 17% of N and 5% of P. Thus, atmospheric deposition is the largest single source of nutrient loading to Cultus Lake, cumulatively responsible for 63% and 42% of total N and P loadings, respectively. Modeled future loading scenarios suggest Cultus Lake could become mesotrophic within the next 25 years, highlighting a heightened need for near-term abatement of P loads. Although mitigating P loads from local watershed sources will slow the rate of eutrophication, management efforts targeting reductions in atmospheric-P within the regional airshed are necessary to halt or reverse lake eutrophication, and conserve both critical habitat for imperiled species at risk and lake-derived ecosystem services.

Black-swan events in animal populations.

Black swans are improbable events that nonetheless occur-often with profound consequences. Such events drive important transitions in social systems (e.g., banking collapses) and physical systems (e.g., earthquakes), and yet it remains unclear the extent to which ecological population numbers buffer or suffer from such extremes. Here, we estimate the prevalence and direction of black-swan events (heavy-tailed process noise) in 609 animal populations after accounting for population dynamics (productivity, density dependence, and typical stochasticity). We find strong evidence for black-swan events in [Formula: see text]4% of populations. These events occur most frequently for birds (7%), mammals (5%), and insects (3%) and are not explained by any life-history covariates but tend to be driven by external perturbations such as climate, severe winters, predators, parasites, or the combined effect of multiple factors. Black-swan events manifest primarily as population die-offs and crashes (86%) rather than unexpected increases, and ignoring heavy-tailed process noise leads to an underestimate in the magnitude of population crashes. We suggest modelers consider heavy-tailed, downward-skewed probability distributions, such as the skewed Student [Formula: see text] used here, when making forecasts of population abundance. Our results demonstrate the importance of both modeling heavy-tailed downward events in populations, and developing conservation strategies that are robust to ecological surprises.

Rethinking Trade-Driven Extinction Risk in Marine and Terrestrial Megafauna.

Large animals hunted for the high value of their parts (e.g., elephant ivory and shark fins) are at risk of extinction due to both intensive international trade pressure and intrinsic biological sensitivity. However, the relative role of trade, particularly in non-perishable products, and biological factors in driving extinction risk is not well understood [1-4]. Here we identify a taxonomically diverse group of >100 marine and terrestrial megafauna targeted for international luxury markets; estimate their value across three points of sale; test relationships among extinction risk, high value, and body size; and quantify the effects of two mitigating factors: poaching fines and geographic range size. We find that body size is the principal driver of risk for lower value species, but that this biological pattern is eliminated above a value threshold, meaning that the most valuable species face a high extinction risk regardless of size. For example, once mean product values exceed US$12,557 kg(-1), body size no longer drives risk. Total value scales with size for marine animals more strongly than for terrestrial animals, incentivizing the hunting of large marine individuals and species. Poaching fines currently have little effect on extinction risk; fines would need to be increased 10- to 100-fold to be effective. Large geographic ranges reduce risk for terrestrial, but not marine, species, whose ranges are ten times greater. Our results underscore both the evolutionary and ecosystem consequences of targeting large marine animals and the need to geographically scale up and prioritize conservation of high-value marine species to avoid extinction.

Ecology of conflict: marine food supply affects human-wildlife interactions on land.

Human-wildlife conflicts impose considerable costs to people and wildlife worldwide. Most research focuses on proximate causes, offering limited generalizable understanding of ultimate drivers. We tested three competing hypotheses (problem individuals, regional population saturation, limited food supply) that relate to underlying processes of human-grizzly bear (Ursus arctos horribilis) conflict, using data from British Columbia, Canada, between 1960-2014. We found most support for the limited food supply hypothesis: in bear populations that feed on spawning salmon (Oncorhynchus spp.), the annual number of bears/km(2) killed due to conflicts with humans increased by an average of 20% (6-32% [95% CI]) for each 50% decrease in annual salmon biomass. Furthermore, we found that across all bear populations (with or without access to salmon), 81% of attacks on humans and 82% of conflict kills occurred after the approximate onset of hyperphagia (July 1(st)), a period of intense caloric demand. Contrary to practices by many management agencies, conflict frequency was not reduced by hunting or removal of problem individuals. Our finding that a marine resource affects terrestrial conflict suggests that evidence-based policy for reducing harm to wildlife and humans requires not only insight into ultimate drivers of conflict, but also management that spans ecosystem and jurisdictional boundaries.

An Evaluation of Rebuilding Policies for U.S. Fisheries.

Rebuilding depleted fish populations is a priority of modern fisheries management. In the U.S., strong statutory mandates extend to both the goals and process by which stocks are to be rebuilt. However, the National Standard Guidelines that govern the implementation of the Magnuson-Stevens Fishery Conservation and Management Act may change to increase flexibility in rebuilding requirements. In this study we evaluate performance of the status quo approach to fish stock rebuilding in the United States against 3 alternatives that have been proposed to improve rebuilding outcomes. These alternatives either simplify the analytical requirements of rebuilding analyses or apply 'best practices' in fisheries management, thereby avoiding the need for rebuilding analyses altogether. We use a Management Strategy Evaluation framework to evaluate rebuilding options across 6 fish life history types and 5 possible real-world fishery scenarios that include options for stock assessment quality, multiple fleets, and the degree to which the stocks are overfished at the start of the analysis. We show that the status quo rebuilding plan and a harvest control rule that reduces harvest rates at low stock size generally achieve the best rebuilding outcomes across all life-history types and fishery scenarios. Both approaches constrain fishing in the short term, but achieve high catches in the medium and long term as stocks rebuild to productive levels. These results support a growing body of literature that indicates that efforts to end overfishing early pay off in the medium- to long-term with higher cumulative catches than the alternative.

Checklist to meet Ethical and Legal Obligations in the consent pathway for critically ill patients (ChELO): A quality improvement project and case studies.

Ethical or legal errors related to the consent pathway for incapable patients are an everyday reality. Quality improvements in communication or palliative care have been attempted, but little attention has been given to meeting basic legal and ethical obligations. In this paper, the authors share lessons learned during two years of implementing the Checklist for meeting Ethical and Legal Obligations (ChELO) in the intensive care unit of a large community hospital in Ontario. We use a case-based approach to demonstrate the need for our intervention, our use of positive deviance in a change strategy, and the effectiveness of the checklist itself. Through stories, we show common ethical and legal errors related to the consent pathway and how we were able to resolve them with this innovative tool.

Portfolio conservation of metapopulations under climate change.

Climate change is likely to lead to increasing population variability and extinction risk. Theoretically, greater population diversity should buffer against rising climate variability, and this theory is often invoked as a reason for greater conservation. However, this has rarely been quantified. Here we show how a portfolio approach to managing population diversity can inform metapopulation conservation priorities in a changing world. We develop a salmon metapopulation model in which productivity is driven by spatially distributed thermal tolerance and patterns of short- and long-term climate change. We then implement spatial conservation scenarios that control population carrying capacities and evaluate the metapopulation portfolios as a financial manager might: along axes of conservation risk and return. We show that preserving a diversity of thermal tolerances minimizes risk, given environmental stochasticity, and ensures persistence, given long-term environmental change. When the thermal tolerances of populations are unknown, doubling the number of populations conserved may nearly halve expected metapopulation variability. However, this reduction in variability can come at the expense of long-term persistence if climate change increasingly restricts available habitat, forcing ecological managers to balance society's desire for short-term stability and long-term viability. Our findings suggest the importance of conserving the processes that promote thermal-tolerance diversity, such as genetic diversity, habitat heterogeneity, and natural disturbance regimes, and demonstrate that diverse natural portfolios may be critical for metapopulation conservation in the face of increasing climate variability and change.

The Impacts of Wind Speed Trends and 30-Year Variability in Relation to Hydroelectric Reservoir Inflows on Wind Power in the Pacific Northwest.

In hydroelectric dominated systems, the value and benefits of energy are higher during extended dry periods and lower during extended or extreme wet periods. By accounting for regional and temporal differences in the relationship between wind speed and reservoir inflow behavior during wind farm site selection, the benefits of energy diversification can be maximized. The goal of this work was to help maximize the value of wind power by quantifying the long-term (30-year) relationships between wind speed and streamflow behavior, using British Columbia (BC) and the Pacific Northwest (PNW) as a case study. Clean energy and self-sufficiency policies in British BC make the benefits of increased generation during low streamflow periods particularly large. Wind density (WD) estimates from a height of 10m (North American Regional Reanalysis, NARR) were correlated with cumulative usable inflows (CUI) for BC (collected from BC Hydro) for 1979-2010. The strongest WD-CUI correlations were found along the US coast (r ~0.55), whereas generally weaker correlations were found in northern regions, with negative correlations (r ~ -0.25) along BC's North Coast. Furthermore, during the lowest inflow years, WD anomalies increased by up to 40% above average values for the North Coast. Seasonally, high flows during the spring freshet were coincident with widespread negative WD anomalies, with a similar but opposite pattern for low inflow winter months. These poorly or negatively correlated sites could have a moderating influence on climate related variability in provincial electricity supply, by producing greater than average generation in low inflow years and reduced generation in wet years. Wind speed and WD trends were also analyzed for all NARR grid locations, which showed statistically significant positive trends for most of the PNW and the largest increases along the Pacific Coast.

Modeling population responses of Chinook and coho salmon to suspended sediment using a life history approach.

This study develops a quantitative framework for estimating the effects of extreme suspended-sediment events (SSC>25 mg L(-1)) on virtual populations of Chinook (Oncorhynchus tshawytscha) and coho (O. kisutch) salmon in a coastal watershed of British Columbia, Canada. We used a life history model coupled with a dose-response model to evaluate the populations' responses to a set of simulated suspended sediments scenarios. Our results indicate that a linear increase in SSC produces non-linear declining trajectories in both Chinook and coho populations, but this decline was more evident for Chinook salmon despite their shorter fresh-water residence. The model presented here can provide insights into SSC impacts on population responses of salmonids and potentially assist resource managers when planning conservation or remediation strategies.

Linking removal targets to the ecological effects of invaders: a predictive model and field test.

Species invasions have a range of negative effects on recipient ecosystems, and many occur at a scale and magnitude that preclude complete eradication. When complete extirpation is unlikely with available management resources, an effective strategy may be to suppress invasive populations below levels predicted to cause undesirable ecological change. We illustrated this approach by developing and testing targets for the control of invasive Indo-Pacific lionfish (Pterois volitans and P. miles) on Western Atlantic coral reefs. We first developed a size-structured simulation model of predation by lionfish on native fish communities, which we used to predict threshold densities of lionfish beyond which native fish biomass should decline. We then tested our predictions by experimentally manipulating lionfish densities above or below reef-specific thresholds, and monitoring the consequences for native fish populations on 24 Bahamian patch reefs over 18 months. We found that reducing lionfish below predicted threshold densities effectively protected native fish community biomass from predation-induced declines. Reductions in density of 25­92%, depending on the reef, were required to suppress lionfish below levels predicted to overconsume prey. On reefs where lionfish were kept below threshold densities, native prey fish biomass increased by 50­70%. Gains in small (<6 cm) size classes of native fishes translated into lagged increases in larger size classes over time. The biomass of larger individuals (>15 cm total length), including ecologically important grazers and economically important fisheries species, had increased by 10­65% by the end of the experiment. Crucially, similar gains in prey fish biomass were realized on reefs subjected to partial and full removal of lionfish, but partial removals took 30% less time to implement. By contrast, the biomass of small native fishes declined by >50% on all reefs with lionfish densities exceeding reef-specific thresholds. Large inter-reef variation in the biomass of prey fishes at the outset of the study, which influences the threshold density of lionfish, means that we could not identify a single rule of thumb for guiding control efforts. However, our model provides a method for setting reef-specific targets for population control using local monitoring data. Our work is the first to demonstrate that for ongoing invasions, suppressing invaders below densities that cause environmental harm can have a similar effect, in terms of protecting the native ecosystem on a local scale, to achieving complete eradication.

Confronting uncertainty in wildlife management: performance of grizzly bear management.

Scientific management of wildlife requires confronting the complexities of natural and social systems. Uncertainty poses a central problem. Whereas the importance of considering uncertainty has been widely discussed, studies of the effects of unaddressed uncertainty on real management systems have been rare. We examined the effects of outcome uncertainty and components of biological uncertainty on hunt management performance, illustrated with grizzly bears (Ursus arctos horribilis) in British Columbia, Canada. We found that both forms of uncertainty can have serious impacts on management performance. Outcome uncertainty alone--discrepancy between expected and realized mortality levels--led to excess mortality in 19% of cases (population-years) examined. Accounting for uncertainty around estimated biological parameters (i.e., biological uncertainty) revealed that excess mortality might have occurred in up to 70% of cases. We offer a general method for identifying targets for exploited species that incorporates uncertainty and maintains the probability of exceeding mortality limits below specified thresholds. Setting targets in our focal system using this method at thresholds of 25% and 5% probability of overmortality would require average target mortality reductions of 47% and 81%, respectively. Application of our transparent and generalizable framework to this or other systems could improve management performance in the presence of uncertainty.

Changes in the distribution of atlantic bluefin tuna (Thunnus thynnus) in the Gulf of Maine 1979-2005.

The Gulf of Maine, NW Atlantic Ocean, is a productive, seasonal foraging ground for Atlantic bluefin tuna (Thunnus thynnus), but commercial landings of adult size classes were up to 40% below the allocated total allowable catch between 2004 to 2008 for the rod and reel, harpoon, and purse seine categories in the Gulf of Maine. Reduction in Atlantic bluefin tuna catches in the Gulf of Maine could represent a decline in spawning stock biomass, but given wide-ranging, complex migration patterns, and high energetic requirements, an alternative hypothesis is that their dispersal patterns shifted to regions with higher prey abundance or profitability, reducing availability to U.S. fishing fleets. This study fit generalized linear models to Atlantic bluefin tuna landings data collected from fishermen's logbooks (1979-2005) as well as the distances between bluefin tuna schools and Atlantic herring (Clupeaharengus), a primary prey species, to test alternative hypotheses for observed shifts in Atlantic bluefin tuna availability in the Gulf of Maine. For the bluefin model, landings varied by day of year, latitude and longitude. The effect of latitude differed by day of year and the effect of longitude differed by year. The distances between Atlantic bluefin tuna schools and Atlantic herring schools were significantly smaller (p<0.05) than would be expected from a randomly distributed population. A time series of average bluefin tuna school positions was positively correlated with the average number of herring captured per tow on Georges Bank in spring and autumn surveys respectively (p<0.01, r(2)=0.24, p<0.01, r(2)=0.42). Fishermen's logbooks contributed novel spatial and temporal information towards testing these hypotheses for the bluefin tuna fishery.

Scarcity: the context of rationing in an Ontario ICU.

OBJECTIVES: Clinicians' perceptions of scarcity influence rationing of critical care resources, which may lead to serious adverse outcomes for patients who are denied access. We sought to better understand the phenomenon of scarcity in the critical care setting. DESIGN: Qualitative research methods. We used purposeful sampling to recruit ICU clinicians who were frequently involved in decisions to allocate ICU resources. Thematic analysis was performed to identify concepts related to the phenomenon of scarcity. SETTING: An ICU of a university-affiliated hospital in Toronto, Canada, between October and December 2007. SUBJECTS: We conducted 22 interviews with 12 ICU physicians, 4 ICU fellows, 2 ICU nursing team leaders, and 4 ICU resource nurses. MAIN RESULTS: The perception of scarcity arose from a complex interaction of factors within the institution including: 1) practices of non-ICU physicians (e.g., failure to specify end-of-life treatment plans or to secure an ICU bed prior to elective high-risk surgery), 2) family demands for life support and clinicians' perception of a lack of legal support if they opposed these, and 3) inability to transfer patients to non-ICU care settings in a timely manner. Implications of scarcity included: 1) diversions of critically ill patients, 2) premature patient transfers, 3) temporary delivery of critical care in non-ICU locations (e.g., emergency department, postanesthesia care unit), and 4) interprofessional conflicts. CONCLUSIONS: ICU clinicians' perceptions of scarcity may lead to rationing of critical care resources. We found that nonmedical factors strongly influenced prioritization activity, both for admission and discharge. Although scarcity of ICU beds might be mitigated by process improvements such as patient flow or proactive communication, our findings highlight the importance of a fair process for inevitable limit setting at the bedside.