254 research outputs found
Clinically-indicated replacement versus routine replacement of peripheral venous catheters (Review)
Background: US Centers for Disease Control guidelines recommend replacement of peripheral intravenous (IV) catheters no more frequently than every 72 to 96 hours. Routine replacement is thought to reduce the risk of phlebitis and bloodstream infection. Catheter insertion is an unpleasant experience for patients and replacement may be unnecessary if the catheter remains functional and there are no signs of inflammation. Costs associated with routine replacement may be considerable. This is an update of a review first published in 2010. Objectives: To assess the effects of removing peripheral IV catheters when clinically indicated compared with removing and re-siting the catheter routinely. Search methods: For this update the Cochrane Vascular Trials Search Co-ordinator searched the Cochrane Vascular Specialised Register (March 2015) and CENTRAL (2015, Issue 3). We also searched clinical trials registries (April 2015). Selection criteria: Randomised controlled trials that compared routine removal of peripheral IV catheters with removal only when clinically indicated in hospitalised or community dwelling patients receiving continuous or intermittent infusions. Data collection and analysis: Two review authors independently assessed trial quality and extracted data. Main results: Seven trials with a total of 4895 patients were included in the review. The quality of the evidence was high for most outcomes but was downgraded to moderate for the outcome catheter-related bloodstream infection (CRBSI). The downgrade was due to wide confidence intervals, which created a high level of uncertainty around the effect estimate. CRBSI was assessed in five trials (4806 patients). There was no significant between group difference in the CRBSI rate (clinically-indicated 1/2365; routine change 2/2441). The risk ratio (RR) was 0.61 (95% CI 0.08 to 4.68; P = 0.64). No difference in phlebitis rates was found whether catheters were changed according to clinical indications or routinely (clinically-indicated 186/2365; 3-day change 166/2441; RR 1.14, 95% CI 0.93 to 1.39). This result was unaffected by whether infusion through the catheter was continuous or intermittent. We also analysed the data by number of device days and again no differences between groups were observed (RR 1.03, 95% CI 0.84 to 1.27; P = 0.75). One trial assessed all-cause bloodstream infection. There was no difference in this outcome between the two groups (clinically-indicated 4/1593 (0.02%); routine change 9/1690 (0.05%); P = 0.21). Cannulation costs were lower by approximately AUD 7.00 in the clinically-indicated group (mean difference (MD) -6.96, 95% CI -9.05 to -4.86; P ≤ 0.00001). Authors' conclusions: The review found no evidence to support changing catheters every 72 to 96 hours. Consequently, healthcare organisations may consider changing to a policy whereby catheters are changed only if clinically indicated. This would provide significant cost savings and would spare patients the unnecessary pain of routine re-sites in the absence of clinical indications. To minimise peripheral catheter-related complications, the insertion site should be inspected at each shift change and the catheter removed if signs of inflammation, infiltration, or blockage are present
Short-range hunters: exploring the function and constraints of water shooting in dwarf gouramis
Ballistic predation is a rare foraging adaptation: in fishes, most attention has focused on a single genus, the archerfish, known to manipulate water to shoot down prey above the water surface. However, several gourami species also exhibit apparently similar ‘shooting’ behaviour, spitting water up to 5 cm above the surface. In a series of experiments, we explored the shooting behaviour and aspects of its significance as a foraging ability in the dwarf gourami (Trichogaster lalius). We investigated sex differences in shooting abilities to determine whether gourami shooting is related to the sex-specific bubble nest manufacture where males mix air and water at the surface to form bubbles. We found that, actually, both sexes were equally able to shoot and could learn to shoot a novel target. In a second experiment, we presented untrained gouramis with opportunities to shoot at live prey and found they successfully shot down both fruit flies and crickets. Finally, we explored the effect of target height on shooting performance to establish potential constraints of shooting as a foraging ability. The frequency of attempted shots and success of hitting targets decreased with height, whereas latency to shoot increased. We also observed that repeatable individual differences account for variation in these measures of shooting performance. Together, our results provide evidence that gourami shooting has a foraging function analogous to that of archerfish. Gourami shooting may serve as an example of convergent evolution and provide opportunities for comparative studies into the, as yet unexplored, ecology and evolution of shooting in fishes.Peer reviewe
Transplant Recipients and Anal Neoplasia Study: Design, Methods, and Participant Characteristics of a Prevalence Study
Kidney recipients have anal cancer rates 3 times higher than the general population in Australia and New Zealand. High-risk human papillomavirus (HPV) genotypes are implicated in the majority of anal cancers. Establishing the epidemiology of anal HPV infection and precursors of anal cancer in transplant recipient populations is 1 consideration in any potential screening program. The Transplant and Anal Neoplasia Study is a cross-sectional study of the prevalence of anal cytological abnormalities and HPV deoxyribonucleic acid in kidney transplant recipients, as well as evaluating the acceptability of an anal cancer screening intervention. The study aims to recruit 100 kidney transplant recipients, older than 18 years, in Australia. Transplant recipients at- tending for a protocol biopsy at 3 and 12 months and annually posttransplant are approached to participate. Participants undergo an anal swab, which is then analyzed using liquid-based cytological examination and tested for the detection of 37 anogenital HPV deoxyribonucleic acid genotypes. Participants also complete a demographic and behavioral questionnaire that covers sexual be- havior, history of anal symptoms, and possible anal cancer risk factors. Associations will be tested using multiple regression anal- ysis. Recruitment for the study began in 2015 and is ongoing. To date, 96 (77%) of 125 kidney transplant recipients approached have consented to the study. The mean age is 48 (median, 47 y; range, 20–76 y), 59% are male, and Northwest European (58%) represented the largest ethnic group. No participants self-identified as Aboriginal or Torres Strait Islander. High consent rates and positive qualitative results suggest that a larger screening program may be well received by kidney transplant recipients, with in- creased resources and some modification to the timing of approach. Further results of the study will inform the possible implemen- tation of a larger screening trial for prevention of anal cancers in kidney and other solid organ transplant recipients
A patient presenting with a perivascular epithelioid cell tumor in the broad ligament: a case report
<p>Abstract</p> <p>Introduction</p> <p>Perivascular epithelioid cell tumors are a family of rare mesenchymal tumors composed of histologically and immunohistochemically distinctive perivascular epithelioid cells. They can originate in any visceral organ or soft tissue and include a range of lesions such as angiomyolipoma, clear cell 'sugar' tumor of the lung, lymphangioleiomyomatosis and clear cell myomelanocytic tumors of the falciparum ligament/ligament teres. Due to their rarity and varied sites and presentation, management of these tumors remains highly challenging.</p> <p>Case Presentation</p> <p>A 46-year-old para 2 Caucasian woman initially presented to the general surgeons at our hospital in North West London with abdominal pain. Laparoscopy revealed a right broad ligament hematoma, which was thought to be iatrogenic in origin, from insertion of the Veress needle at the time of surgery, and was managed conservatively. Upon her re-presentation two months later with severe pain, ultrasound scanning revealed the hematoma had increased in size and she underwent a total abdominal hysterectomy and bilateral salpingo-oophorectomy. Histology results from necrotic tissue from the hematoma led to a diagnosis of perivascular epithelioid cell tumor. She was then referred to a tertiary oncology center, where she underwent several further operations in an attempt to debulk the tumor for symptomatic relief of her pain, with limited success. She is now taking the immunosuppressive drug sirolimus, which has produced a modest reduction in tumor size. She is now 47 months on from initial presentation.</p> <p>Conclusions</p> <p>A literature search has revealed only six other case reports of broad ligament perivascular epithelioid cell tumors, with varied presentations and management. The longest duration of follow-up was 21 months. Only five other cases of perivascular epithelioid cell tumor managed with sirolimus have been reported. We therefore feel that this report highlights some of the difficulties in diagnosing perivascular epithelioid cell tumors, and sheds light on management strategies for a very rare gynecological tumor in addition to sharing our experience in the use of sirolimus in its treatment.</p
The Methane Diurnal Variation and Microseepage Flux at Gale Crater, Mars as Constrained by the ExoMars Trace Gas Orbiter and Curiosity Observations
The upper bound of 50 parts per trillion by volume for Mars methane above 5 km established by the ExoMars Trace Gas Orbiter, substantially lower than the 410 parts per trillion by volume average measured overnight by the Curiosity Rover, places a strong constraint on the daytime methane flux at the Gale crater. We propose that these measurements may be largely reconciled by the inhibition of mixing near the surface overnight, whereby methane emitted from the subsurface accumulates within meters of the surface before being mixed below detection limits at dawn. A model of this scenario allows the first precise calculation of microseepage fluxes at Gale to be derived, consistent with a constant 1.5 à 10â 10 kg·mâ 2·solâ 1 (5.4 à 10â 5 tonnes·kmâ 2·yearâ 1) source at depth. Under this scenario, only 2.7 à 104 km2 of Mars’s surface may be emitting methane, unless a fast destruction mechanism exists.Plain Language SummaryThe ExoMars Trace Gas Orbiter and the Curiosity Rover have recorded different amounts of methane in the atmosphere on Mars. The Trace Gas Orbiter measured very little methane (<50 parts per trillion by volume) above 5 km in the sunlit atmosphere, while Curiosity measured substantially more (410 parts per trillion by volume) near the surface at night. In this paper we describe a framework which explains both measurements by suggesting that a small amount of methane seeps out of the ground constantly. During the day, this small amount of methane is rapidly mixed and diluted by vigorous convection, leading to low overall levels within the atmosphere. During the night, convection lessens, allowing methane to build up near the surface. At dawn, convection intensifies and the nearâ surface methane is mixed and diluted with much more atmosphere. Using this model and methane concentrations from both approaches, we are ableâ for the first timeâ to place a single number on the rate of seepage of methane at Gale crater which we find equivalent to 2.8 kg per Martian day. Future spacecraft measuring methane near the surface of Mars could determine how much methane seeps out of the ground in different locations, providing insight into what processes create that methane in the subsurface.Key PointsNighttime SAMâ TLS seasonal cycle enrichment measurements and TGO sunset/sunrise measurements are not in oppositionMicroseepage fluxes must be local to Gale, range from 0.82 to 4.6 kg/sol, and are consistent with a constant source at depthLittle of Mars experiences microseepage unless a fast destruction mechanism exists or Gale is very unusualPeer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151840/1/grl59471-sup-0001-2019GL083800-SI.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151840/2/grl59471_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151840/3/grl59471.pd
Risk factors for peripheral intravenous catheter failure: a multivariate analysis of data from a randomized controlled trial
Objective.To assess the relative importance of independent risk factors for peripheral intravenous catheter (PIVC) failure.Methods.Secondary data analysis from a randomized controlled trial of PIVC dwell time. The Prentice, Williams, and Peterson statistical model was used to identify and compare risk factors for phlebitis, occlusion, and accidental removal.Setting.Three acute care hospitals in Queensland, Australia.Participants.The trial included 3,283 adult medical and surgical patients (5,907 catheters) with a PIVC with greater than 4 days of expected use.Results.Modifiable risk factors for occlusion included hand, antecubital fossa, or upper arm insertion compared with forearm (hazard ratio [HR], 1.47 [95% confidence interval (CI), 1.28--1.68], 1.27 [95% CI, 1.08--1.49], and 1.25 [95% CI, 1.04--1.50], respectively); and for phlebitis, larger diameter PIVC (HR, 1.48 [95% CI, 1.08--2.03]). PIVCs inserted by the operating and radiology suite staff had lower occlusion risk than ward insertions (HR, 0.80 [95% CI, 0.67--0.94]). Modifiable risks for accidental removal included hand or antecubital fossa insertion compared with forearm (HR, 2.45 [95% CI, 1.93--3.10] and 1.65 [95% CI, 1.23--2.22], respectively), clinical staff insertion compared with intravenous service (HR, 1.69 [95% CI, 1.30--2.20]); and smaller PIVC diameter (HR, 1.29 [95% CI, 1.02--1.61]). Female sex was a nonmodifiable factor associated with an increased risk of both phlebitis (HR, 1.64 [95% CI, 1.28--2.09]) and occlusion (HR, 1.44 [95% CI, 1.30--1.61]).Conclusions.PIVC survival is improved by preferential forearm insertion, selection of appropriate PIVC diameter, and insertion by intravenous teams and other specialists.Trial registration.The original randomized controlled trial on which this secondary analysis is based is registered with the Australian New Zealand Clinical Trials Registry (http://www.anzctr.org.au; ACTRN12608000445370)
Characterisation of a Wheat Breeders’ Array suitable for high throughput SNP genotyping of global accessions of hexaploid bread wheat (<i>Triticum aestivium</i>)
Targeted selection and inbreeding have resulted in a lack of genetic diversity in elite hexaploid bread wheat accessions. Reduced diversity can be a limiting factor in the breeding of high yielding varieties and crucially can mean reduced resilience in the face of changing climate and resource pressures. Recent technological advances have enabled the development of molecular markers for use in the assessment and utilization of genetic diversity in hexaploid wheat. Starting with a large collection of 819 571 previously characterized wheat markers, here we describe the identification of 35 143 single nucleotide polymorphism-based markers, which are highly suited to the genotyping of elite hexaploid wheat accessions. To assess their suitability, the markers have been validated using a commercial high-density Affymetrix Axiom® genotyping array (the Wheat Breeders' Array), in a high-throughput 384 microplate configuration, to characterize a diverse global collection of wheat accessions including landraces and elite lines derived from commercial breeding communities. We demonstrate that the Wheat Breeders' Array is also suitable for generating high-density genetic maps of previously uncharacterized populations and for characterizing novel genetic diversity produced by mutagenesis. To facilitate the use of the array by the wheat community, the markers, the associated sequence and the genotype information have been made available through the interactive web site 'CerealsDB'
Dressings and securements for the prevention of peripheral intravenous catheter failure in adults (SAVE): a pragmatic, randomised controlled, superiority trial
Background: Two billion peripheral intravenous catheters (PIVCs) are used globally each year, but optimal dressing and securement methods are not well established. We aimed to compare the efficacy and costs of three alternative approaches to standard non-bordered polyurethane dressings. Methods: We did a pragmatic, randomised controlled, parallel-group superiority trial at two hospitals in Queensland, Australia. Eligible patients were aged 18 years or older and required PIVC insertion for clinical treatment, which was expected to be required for longer than 24 h. Patients were randomly assigned (1:1:1:1) via a centralised web-based randomisation service using random block sizes, stratified by hospital, to receive tissue adhesive with polyurethane dressing, bordered polyurethane dressing, a securement device with polyurethane dressing, or polyurethane dressing (control). Randomisation was concealed before allocation. Patients, clinicians, and research staff were not masked because of the nature of the intervention, but infections were adjudicated by a physician who was masked to treatment allocation. The primary outcome was all-cause PIVC failure (as a composite of complete dislodgement, occlusion, phlebitis, and infection [primary bloodstream infection or local infection]). Analysis was by modified intention to treat. This trial is registered with the Australian New Zealand Clinical Trials Registry, number ACTRN12611000769987. Findings: Between March 18, 2013, and Sept 9, 2014, we randomly assigned 1807 patients to receive tissue adhesive with polyurethane (n=446), bordered polyurethane (n=454), securement device with polyurethane (n=453), or polyurethane (n=454); 1697 patients comprised the modified intention-to-treat population. 163 (38%) of 427 patients in the tissue adhesive with polyurethane group (absolute risk difference −4·5% [95% CI −11·1 to 2·1%], p=0·19), 169 (40%) of 423 of patients in the bordered polyurethane group (–2·7% [–9·3 to 3·9%] p=0·44), 176 (41%) of 425 patients in the securement device with poplyurethane group (–1·2% [–7·9% to 5·4%], p=0·73), and 180 (43%) of 422 patients in the polyurethane group had PIVC failure. 17 patients in the tissue adhesive with polyurethane group, two patients in the bordered polyurethane group, eight patients in the securement device with polyurethane group, and seven patients in the polyurethane group had skin adverse events. Total costs of the trial interventions did not differ significantly between groups. Interpretation: Current dressing and securement methods are commonly associated with PIVC failure and poor durability, with simultaneous use of multiple products commonly required. Cost is currently the main factor that determines product choice. Innovations to achieve effective, durable dressings and securements, and randomised controlled trials assessing their effectiveness are urgently needed
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