Perioperative arterial catheterization: A prospective evaluation of ultrasound, infection, and patient-focused outcomes

BACKGROUND

There is little information regarding complications of arterial catheterization in modern clinical care. We aimed to determine the incidence of abnormal duplex vascular ultrasound and catheter related infections following perioperative arterial catheterization.

METHODS

Patients requiring arterial catheterization for elective surgery were included and insertion details collected prospectively. Duplex ultrasound evaluation was performed 24 h after catheter removal. Symptomatic patients were identified by self-reported questionnaire. On Day 7, patients answered questions by telephone, related to the insertion site, pain, and function. Results of catheter tip and blood culture analyses were sought. Univariate associations of patient and surgical characteristics with abnormal ultrasound were assessed with p < 0.05 considered significant.

RESULTS

Of 339 catheterizations, 105 (40%) had ultrasound evaluation. Catheters were indwelling for median (IQR, range) duration of 6.0 h (4.4-8.2, 1.8-28) with no catheter-related infections. There were 16 (15.2%, 95% CI 9.0%-23.6%) abnormal results, including 14 radial artery thromboses, one radial artery dissection, and one radial vein thrombosis. Those with abnormal ultrasound results were more likely to have had Arrow catheters inserted (68.8% vs 27%, p = 0.023) and more than one skin puncture (37.5% vs 26.8%, p = 0.031). Two of the 16 (12.5%) patients with abnormal ultrasound results reported new symptoms related to the hand compared with nine of the 88 (10.2%) with normal results (p = 0.1). No patients required urgent referral for management.

CONCLUSIONS

Thrombosis was the most common abnormality and was usually asymptomatic. There were no infections, few post-operative symptoms, and minimal functional impairment following arterial catheterization.

Implementation of the GAA 'healthy clubs project' in Ireland: a qualitative study using the Consolidated Framework for Implementation Research

The sports clubs' role in promoting health has been acknowledged by policy makers and researchers, but there is little evidence on how sports clubs implement health-related interventions. The present article investigates the Gaelic Athletic Association Healthy Club Project (HCP) implementation process (mechanisms, barriers, leverages) over a 10-year timeframe. A case study design helped to produce and compare a data synthesis for five clubs involved since 2013. A qualitative iterative data collection, including document analysis was conducted through 20 focus groups with Healthy Club Officers, coaches, participants and members. The Consolidated Framework for Implementation Research was used in the deductive analysis process, conducted by the first author. Results have shown the success of the HCP in placing health promotion on the agenda of sports clubs leading to informal policy for health promotion, even if activities and recognition are directed toward and coming from the community. This study also underlines the virtuous cycle of the settings-based approach in enhancing membership and volunteer recognition through health promotion actions, and the importance of social good and corporate social activities for sports clubs. Nevertheless, the HCP still relies on limited human resources, is not recognized by competitive oriented adult playing members. and acknowledged as a resource by some coaches, limiting its rootedness in the core business of sports clubs. Future research should empower the HCP community to focus on organizational changes and develop outcomes for individuals, for the club as a whole as well as for the local community.

Care bundles and peripheral arterial catheters

HIGHLIGHTS

What we know about the topic: Recommendations for the use of vascular access care bundles to reduce infection are followed for different devices. The risk of arterial catheter-related infection is comparable with short-term, non-cuffed central venous catheters. There are practice concerns for clinicians inserting and caring for peripheral arterial catheters. What this paper adds: The selected studies had a theme of decreased infection after using bundled strategies for all devices. Few studies addressed use of bundles for care of peripheral arterial catheters. High-quality research should be performed about using care bundles for insertion and care of arterial catheters.

INTRODUCTION

A scoping review of the literature was performed.

AIMS/OBJECTIVES

To find information on the use of care bundles for care of arterial, central, and peripherally inserted venous catheters.

METHODS

Data was extracted by 2 independent researchers using standardized methodology.

RESULTS

Results of 84 studies included 2 (2.4%) randomized controlled trials, 38 (45.2%) observational studies, 29 (34.5%) quality projects, and 15 (17.9%) reviews. Populations had more adults than pediatric patients. All studies had the most prominent theme of decreased infection in all devices after using bundle strategies.

DISCUSSION AND CONCLUSIONS

The mapping of available evidence strongly supports the use of care bundles to reduce infection in the care of all intravascular devices. However, deficiencies regarding practice concerns about insertion and care of arterial catheters highlight areas for future research with the aim to eliminate the gap in the evidence of studies of care bundles for peripheral arterial catheters.

Transcutaneous carbon dioxide measurements in anesthetized apneic patients with BMI > 35 kg/m2

Transcutaneous carbon dioxide measurement (TcCO2) offers the ability to continuously and non-invasively monitor carbon dioxide (CO2) tensions when end-tidal monitoring is not possible. The accuracy of TcCO2 has not been established in anesthetized apneic patients with obesity. In this secondary publication, we present a methods comparison analysis of TcCO2 with the gold standard arterial PCO2, in adult patients with body mass index (BMI) > 35kg/m2 who were randomized to receive high flow or low flow nasal oxygenation during post-induction apnea. Agreement between PaCO2 and TcCO2 at baseline, the start of apnea and the end of apnea were assessed using a non-parametric difference plot. Forty-two participants had a median (IQR) BMI of 52 (40-58.5) kg/m2. The mean (SD) PaCO2 was 33.9 (4.0) mmHg at baseline and 51.4 (7.5) mmHg at the end of apnea. The bias was the greatest at the end of apnea median (95% CI, 95% limits of agreement) 1.90 mmHg (-2.64 to 6.44, -7.10 to 22.90). Findings did not suggest significant systematic differences between the PaCO2 and TcCO2 measures. For a short period of apnea, TcCO2 showed inadequate agreement with PaCO2 in patients with BMI > 35 kg/m2. These techniques require comparison in a larger population, with more frequent sampling and over a longer timeframe, before TcCO2 can be confidently recommended in this setting.

Development of a sports technology quality framework

Identifying tools and processes to effectively and efficiently evaluate technologies is an area of need for many sport stakeholders. This study aimed to develop a standardised, evidence-based framework to guide the evaluation of sports technologies. In developing the framework, a review of standards, guidelines and research into sports technology was conducted. Following this, 55 experts across the sports industry were presented with a draft framework for feedback. Following a two-round Delphi survey, the final framework consisted of 25 measurable features grouped under five quality pillars. These were 1) Quality Assurance & Measurement (Accuracy, Repeatability, Reproducibility, Specifications), 2) Established Benefit (Construct Validity, Concurrent Validity, Predictive Validity, Functionality), 3) Ethics & Security (Compliance, Privacy, Ownership, Safety, Transparency, Environmental Sustainability), 4) User Experience (Usability, Robustness, Data Representation, Customer Support & Training, Accessibility) & 5) Data Management (Data Standardisation, Interoperability, Maintainability, Scalability). The framework can be used to help design and refine sports technology in order to optimise quality and maintain industry standards, as well as guide purchasing decisions by organisations. It may also serve to create a common language for organisations, manufacturers, investors, and consumers to improve the efficiency of their decision-making relating to sports technology.

Remotely supervised ultrasound-guided peripheral intravenous cannulation training: A prospective cohort study examining success rates and patient experience

Introduction

Ultrasound-guided peripheral intravenous cannulation (USGPIVC) benefits patients with difficult intravenous access (DIVA) through visualising otherwise non-visible and non-palpable veins. Supervised live-case training is an important component of learning this skill, but supervisor availability can present a barrier limiting or delaying staff completing their training.

Aims

The aim of this study was to determine the first-attempt success rate of newly trained USGPIVC inserters using remote supervision and timely written feedback based on app-based screen recordings taken during insertion. Secondary aims were overall procedural success, and inserter and patient experiences.

Methods

This study is an observational cohort study carried out between October and December 2021. Fourteen newly trained junior medical officers (JMOs) were eligible to utilise USGPIVC on a minimum of five consenting patients while simultaneously recording the ultrasound screen during insertion to capture their technique. Feedback was generated following expert review of these recordings against a standardised feedback tool.

Results

Average first-attempt success was 71% (n = 72) in the 102 patients recruited. The average time for JMOs to receive feedback was 30 h, and 13 JMOs (93%) felt well supported and completed the remote training pathway. The majority of patients were female (n = 59; 58%), were aged 41-80 years (n = 75; 74%) and had ≥2 risk factors for DIVA (n = 57; 56%).

Conclusions

First-attempt success rates were similar when comparing remote supervision used in this study to direct supervision used by other studies.This finding supports incorporating remote supervision into training guidelines for USGPIVC as an alternative method of supervision, particularly when supervisor availability is limited.

The development of the Physical Activity Environment Policy Index (PA-EPI): a tool for monitoring and benchmarking government policies and actions to improve physical activity

Background

Insufficient physical activity (PA) is a global issue for health. A multifaceted response, including government action, is essential to improve population levels of PA. The purpose of this study was to develop the ‘Physical Activity Environment Policy Index’ (PA-EPI) monitoring framework to assess government policies and actions for creating a healthy PA environment.

Methods

An iterative process was undertaken. This involved a review of policy documents from authoritative organisations, a policy audit of four European countries, and systematic reviews of scientific literature. This was followed by an online consultation with academic experts (N = 101; 20 countries, 72% response rate), and policymakers (N = 40, 4 EU countries). During this process, consensus workshops where quantitative and qualitative data alongside theoretical and pragmatic considerations were used to inform PA-EPI development.

Results

The PA-EPI is conceptualised as a two-component ‘policy’ and ‘infrastructure support’ framework. The two components comprise eight policy and seven infrastructure support domains. The policy domains are education, transport, urban design, healthcare, public education (including mass media), sport-for-all, workplaces and community. The infrastructure support domains are leadership, governance, monitoring and intelligence, funding and resources, platforms for interaction, workforce development, and health-in-all-policies. Forty-five ‘good practice statements’ (GPS) or indicators of ideal good practice within each domain concludes the PA-EPI. A potential eight-step process for conducting the PA-EPI is described.

Conclusions

Once pre-tested and piloted in several countries of various sizes and income levels, the PA-EPI GPS will evolve into benchmarks established by governments at the forefront of creating and implementing policies to address inactivity.

Sport federation investment in health promotion: program implementation and viability

Background

Researchers have called for a better recognition of the potential of sports clubs for health promotion (HP), but less is known on the support provided by sports federation. The present study analyses the the implementation of the Gaelic Athletics Association (GAA) Healthy Club Project, to investigate its organization’s viability.

Methods

A single case study was realized, based on observation, document analysis and interviews, to document the viable system model.

Results

Results have identified a three-level structure, where 6 employees at national level support the work of 28 volunteer’s county health and well-being officers and 439 clubs implicated. Strengths of the organization are the identification of a single national referent for clubs or county, the learning process and openness to novelty, as well as the enhanced workforce through county implication as role model. Challenges are the financial and human resources provision, the ability to implicate county and club board and the training in HP of volunteers. Interlevel relationship are supported by the creation of a community of practice and the centralization of the project at national level, but hindered by a clear definition of county tasks. The strengths of the controlling system include a steering committee implicating partners completing each other and the proper use of evaluation to build evidence on the project, where challenges remains in wider collaboration within the GAA.

Conclusions

The present work has underlined key scaling up factors of the HCP implementation to support its viability, which could be learnt from other sports federation implementing HP interventions.

Key messages

• Sports federation have a key role to play to support sports clubs to promote health, by developing specific programs.

• Health Promotion development in sports clubs has similar scaling up implementation factor than other public health interventions.

Use of an active esophageal cooling device in zero-fluoroscopy settings without intracardiac echocardiography

Background

Active esophageal cooling is increasingly being utilized during radiofrequency (RF) ablation to achieve pulmonary vein isolation (PVI) for the treatment of atrial fibrillation (AF). In addition to data showing decreases in severe esophageal injury with active esophageal cooling, placement of a commercially available cooling device can be identified on intracardiac echocardiography (ICE), allowing implementation in zero-fluoroscopy settings. In the case of procedures that do not have ICE available, an alternative method to determine proper placement of an esophageal cooling device is needed in zero-fluoroscopy settings..

Purpose

To describe a large single-center approach to visualizing an active esophageal cooling device into a 3D mapping system.

Methods

We reviewed data on patients treated with RF ablation for PVI procedures over the time frame 1/1/2020 to 12/31/21. Active esophageal cooling was phased in towards the end of 2020. For all cases, transseptal puncture was performed with the use of transesophageal echocardiography (TEE). After successful transseptal puncture, the TEE probe was removed, and either a single-sensor LET probe or an active esophageal cooling device was placed. For the active cooling device, the distal tip was cut, and an SL-1 (0.032 inch, 150 cm length) guidewire was placed through the central lumen of the cooling device (used for gastric suctioning and enteral feeding). The guidewire was pinned via a pin block to the 3D mapping system (EnSite, Abbott). Unipolar configuration was used to generate a 3D map, which was then visualized during device placement. Placement was confirmed after visualizing the guidewire tip on the 3D map passing below the coronary sinus (Figure 1).

Results

A total of 417 cases were performed over the study timeframe. The mean age of patients was 65±10 years, and 40% were female. A total of 5 complications were recorded (3 pericardial effusions, 1 pseudoaneurysm, and 1 air embolism). A total of 156 patients received LET monitoring, and 261 received active esophageal cooling. The mean procedure length was 109±24 minutes for cases utilizing LET monitoring, and 93±11 minutes for cases utilizing active esophageal cooling. Visualization of the active esophageal cooling device on the cardiac mapping system was possible in all cases.

Conclusions

We describe here the largest series to date utilizing active esophageal cooling in a zero-fluoroscopy, zero-ICE setting. With increasing efforts to reduce fluoroscopy, this approach allows pursuit of zero-fluoroscopy even in systems without the availability of ICE, while maintaining procedural speed and safety.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Attune Medical

Poor correlation between airway fluoroscopy and rigid bronchoscopic evaluation in paediatric tracheomalacia

INTRODUCTION

Tracheomalacia is a common congenital condition causing stridor in young children. However, the evaluation of these children remains poorly standardised across institutions.

METHODS

We conducted a retrospective review of all children undergoing an elective laryngotracheobronchoscopy at a single tertiary paediatric institution between March 2010 and December 2018. Emergency bronchoscopies and children with tracheostomies were excluded. 1163 children undergoing an elective bronchoscopy were included in this study, and 545 children also had an airway fluoroscopy.

RESULTS

The median age at bronchoscopy was 17 months, and the majority of children were male. Tracheomalacia was diagnosed in 21.6% of children at bronchoscopy, of these 48.5% had tracheomalacia diagnosed on a previous airway fluoroscopy. Overall, airway fluoroscopy had a low sensitivity (62.3%) and a low specificity (67.5%) for diagnosis of tracheomalacia when compared with bronchoscopy. Increasing severity of tracheomalacia on airway screen significantly predicted a diagnosis of tracheomalacia on bronchoscopy.

CONCLUSIONS

Airway fluoroscopy has a low sensitivity and specificity in diagnosis of tracheomalacia and should be used judiciously rather than as a screening tool for children with stridor. However, this imaging technique may be beneficial in investigating children with severe symptoms who have had other conditions such as laryngomalacia excluded.

Multimodality planning of stereotactic radio-ablation for ventricular tachycardia. Results from the international MUSIC consortium

Funding Acknowledgements

Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Research Council

Background

Optimal SBRT planning methods for VT ablation are yet to be defined.

Purpose

To evaluate a multimodal approach for SBRT planning.

Methods

30 pts (age 70±10, 90% men, LVEF 26±9%, 67% ICM, 47% NICM or mixed, 1.7±1.2 prior catheter ablations) with drug-refractory VT underwent imaging prior to SBRT. The inHEART technology was used to create image-based 3D models of substrate, cardiac anatomy, and organs at risk (coronaries, phrenic nerve, GI tract, AV node). In MUSIC software (IHU Liryc-Inria), 3D models were fused with prior EP maps, and SBRT targets were interactively drawn in 3D by the referring EP cardiologist. Transmural target volumes and organs at risk were fused with a 4D planning CT and used to plan SBRT in Eclipse (Varian).

Results

SBRT was delivered on median PTVs of 96[63-149] mL (total dose 25 Gy) with either Truebeam or Edge systems (Varian). Over a median FU of 4[2-8] months, death occurred in 11(37%) pts, due to arrhythmia recurrence in 4(13%). FU at 6 months was available in 14 pts. In these, the median numbers of VT episodes and ICD shocks over the 6 months preceding SBRT were 20[9-27] and 8[5-15], respectively. In the 6 months following SBRT, these decreased to 0[0-30] and 0[0-0], respectively (P&lt;0.001 for both). 8/14(57%) pts were free from any VT recurrence, and 11/14(79%) were free from any ICD shock. In the total cohort, complications attributed to SBRT were observed in 2/30 (7%), none of which were fatal (heart failure and pneumonitis, both managed with steroids).

Conclusion

In patients with severe drug- and catheter ablation-refractory VT, SBRT planning based on 3D image-based models fused with prior EP maps is feasible, and associated with favorable efficacy and safety profiles.

Exercise Compared to Mindfulness for Physical and Mental Wellbeing in Medical Students

Aim Physical Activity (PA) and Mindfulness-Based Stress Reduction (MBSR) both have positive effects on medical student well-being. The 'MED-WELL' programme is a curricular intervention that combines PA and education on exercise as medicine. This trial evaluates whether there is a mean difference in outcomes of participants of an exercise intervention, the 'MED-WELL' programme, versus a control group which engages in a MBSR programme. Methods All second-year medical students were voluntarily allocated into the intervention or control group. Data on overall health and well-being, sleep quality, loneliness, current level of PA, and confidence in prescribing exercise as medicine was analysed from both groups at baseline and after eight weeks. Results Within groups the intervention and control groups showed statistically significant improvements in overall well-being (p=0.010, p=0.005 respectively) and in sleep quality (p<0.001, p=0.007 respectively). The intervention group had statistically significant improvements in levels of PA (p=0.003) and confidence in prescribing exercise (p<0.001). However, there were no statistically significant differences in changes in outcome measures between groups. Conclusion This study has shown that participants in an exercise intervention, the 'MED-WELL' programme, had similar improvements in overall wellbeing and sleep quality to those in a control group who participated in a MBSR programme of the same duration.

Interventions Designed to Improve Narrative Language in School-Age Children: A Systematic Review With Meta-Analyses

Purpose The purpose of this systematic review with meta-analyses was to examine interventions that aimed to improve narrative language outcomes for preschool and elementary school-age children in the United States. Our goal was to examine peer-reviewed publications to describe the characteristics of these interventions and synthesize their overall effectiveness on narrative comprehension and production via meta-analysis. Method We searched electronic databases, examined previously published reviews, and consulted experts in the field to identify published studies that employed robust experimental and quasi-experimental designs. We included randomized controlled trials, studies with nonrandomized comparison groups, and single-case design (SCD) studies. We completed a qualitative synthesis of study factors for all identified studies and calculated meta-analyses for the studies that had sufficient data. All included studies were analyzed for risk of bias. Results Our systematic search yielded 40 studies that included one or more narrative language outcomes as part of their assessment battery. Twenty-four of the included studies were group design studies, including randomized controlled trials and quasi-experimental designs, and the other 16 were SCD studies. Effect sizes were analyzed based on narrative production and comprehension outcomes. The meta-analyses of 26 studies indicated overall positive effects of the interventions, with effect sizes of d = 0.51 and 0.54 in the group design studies and d = 1.24 in the SCD studies. Conclusions A variety of effective interventions were found that improve narrative production and comprehension outcomes in children with diverse learner characteristics. Some common characteristics across these interventions include manualized curricula, opportunities to produce narrative language, verbal and visual supports, direct instruction of story grammar, and use of authentic children's literature. Supplemental Material https://doi.org/10.23641/asha.15079173.

Systematic review examining the evidence for impact of school policies on physical activity

Background

Epidemiological evidence has demonstrated that physical activity can have substantive health benefits for children and young people. The 'Policy Evaluation Network' is a multi-disciplinary research network across 7 European countries and New Zealand aimed at building capacity and evaluating the level of impact of policy interventions for promoting healthy lifestyles. The Toronto Charter identified 'whole-of-school' programmes as one of seven key investments for promotion of PA. This paper presents results of a SLR, designed to assess the level of evidence for policies within the school setting that contribute directly or indirectly to increasing PA.

Methods

Researchers searched six online databases for scientific literature regarding PA policy interventions in the school setting using key concepts of policy, school, PA and evaluation. Risk of bias will be assessed with tools appropriate to the design of the studies considered. Evidence of actual or potential positive PA outcomes arising directly or indirectly from policy actions will be catalogued.

Results

Preliminary searches identified 2327 unique scientific articles. 1938 (83.3%) were excluded on first reading and 189 (8.8%) were included for full text analysis. Initial findings suggest that organisational policies, for example avoiding overcrowding in playgrounds during school breaks, may be a promising policy action. Detailed analysis revealing other potential policy actions supported by evidence will be presented (SLR in progress).

Conclusions

Preliminary findings suggest that few studies link policy actions in the school setting to PA outcomes. However, studies that have investigated the effects of changes to the school environment on PA levels may provide evidence for policy actions. Preliminary recommendations include strengthening the evidence base for school-based PA policy by supporting studies into the effects of particular policy or legislative changes on PA outcomes.

Key messages

School physical activity policies are an underappreciated public health intervention. More studies should link policy changes to physical activity outcomes.

Sub-national structures matter when evaluating physical activity promotion: Lessons from Germany

Background

Public policies are increasingly acknowledged as important part of promoting physical activity (PA). However, especially in states with sub-national administrative structures such as Germany, national and sub-national approaches differ considerably. In Germany, sport for all (SfA) promotion is mostly organized at sub-national level, which is usually not covered in national evaluations. Knowledge of these structures helps to understand national outcomes, enables comparisons and learning within and between countries, and assists in identifying support structures for effective PA promotion.

Methods

Data were collected in the PEN Policy Evaluation Network project. In addition to the WHO HEPA PAT, a questionnaire was sent to the sports representatives of the 16 federal states. Responses of 11 state representatives were included and overarching issues were identified using inductive thematic analysis.

Results

PA promotion in Germany is organized in three areas: SfA, professional sports and school sports. SfA promotion at sub-national level is assigned to different administrative bodies (ministries, senate administration, state chancellery) and policy areas: culture, health and care, home affairs with various aspects, education, social affairs and family. The priorities of the federal states are more diverse and specific compared to the national level. There is an overlap in the topics: urban planning, cycling, health prevention and targeting children. Cooperation mechanisms and partners vary between federal states, but some partners are active at sub-national and national level.

Conclusions

The results provide an insight into the complexity of PA and especially SfA promotion at sub-national level in Germany. Our results suggest that a broader range of approaches is used in the 16 German states than national overviews would suggest. These particularities must be taken into account when assessing and comparing the results from different countries.

Key messages

The promotion of SfA at German sub-national level is much more diverse than represented at national level evaluations. Knowledge of sub-national structures enables the understanding of national outcomes, the promotion of cross-national learning and the identification of supportive structures for effective PA promotion.

0005 Cataplexy Triggered by Social Cues: A Role for Oxytocin in the Amygdala

Introduction

People with narcolepsy type 1 report that cataplexy is triggered most often by positive social experiences such as laughing with friends, yet the mechanisms through which social interaction promotes cataplexy are unknown. We hypothesize a subpopulation of central amygdala neurons that are sensitive to the prosocial neuropeptide, oxytocin (CeAOTR), respond to positive valence and trigger cataplexy.

Methods

We have used in vivo calcium imaging, chemogenetic and optogenetic approaches to characterize the activity pattern of these neurons and to manipulate their activity state.

Results

Cre-dependent anterograde tracing of the CeAOTR neurons of the central amygdala indicate a moderate to dense projection to the REM sleep-regulatory region of the ventral lateral periaqueductal gray (vlPAG). Additionally, Channel Rhodopsin Assisted Circuit Mapping (CRACM) experiments show that CeAOTR neurons inhibit vlPAG neurons that innervate the REM atonia-promoting region, the sublaterodorsal nucleus. Targeted photostimulation (15Hz (10ms) for 20sec every hour) of the CeAOTR fibers in the vlPAG doubled the amount of cataplexy. Preliminary in vivo calcium imaging indicates that the CeAOTR are active just prior to the onset of cataplexy. Chemogenetic and optogenetic activation of CeAOTR neurons increased cataplexy.

Conclusion

We conclude that the CeAOTR subpopulation is sufficient to promote cataplexy. Our future directions include determining the necessity of these oxytocin sensitive neurons in cataplexy under different conditions of positive valence.

Support

R01 NS106032 and WakeUp Narcolepsy.

Role of Patients and Parents in Pediatric Drug Development

Patient engagement in health care has been an emerging priority in the global effort and move toward the consideration of patients as experts of their own conditions. However, the input of pediatric patients and their families have not been consistently requested nor regarded as valuable when deriving protocols for, as well as assessing the outcomes of, pediatric clinical trials. Extending this mutual collaboration further upstream is important, especially in the area of pediatric drug development where the lack of formalized trials for children and adolescents result in the increased use of off-label prescribing and risk of adverse effects. While recent changes to European and North American legislation contributed to the inclusion of children and youth in pediatric drug development, the lack of systematic guidelines and methodologies in literature serve as barriers for practical application. When combined with the work of external pediatric advocacy and patient advisory groups, the hope is that pediatric patient voices can be brought forward for the future. This article brings together international experts to review current best practices, progress from regulatory agencies, as well as global advocacy efforts to involve patients and families in the pursuit of drug development processes that value the voice of children and youth.

Nurses' decision-making about intravenous administration set replacement: A qualitative study

AIMS AND OBJECTIVES

To explore nurses' decision-making regarding intravenous administration set replacement for vascular access device infusions in paediatric and adult clinical settings.

BACKGROUND

Intravenous administration sets are routinely replaced at regular intervals in clinical practice with the goal of preventing catheter-related bloodstream infection; however, emerging evidence is challenging traditional hang-time durations. Nurses' perceptions and contextual factors affecting decision-making for administration set replacement have not been assessed previously.

DESIGN

Qualitative study using focus groups with contextualism methodology and inductive analysis.

METHOD

During November-December 2016, eight semi-structured focus groups were conducted with 38 nurses at two metropolitan hospitals in Queensland, Australia. Interviews were audio-recorded and transcribed. Two authors independently reviewed transcripts and extracted significant statements using Braun and Clarke's 7-step method of thematic analysis. The COREQ checklist provided a framework to report the study methods, context, findings, analysis and interpretation.

RESULTS

Five key themes emerged from the analysis: (a) infection prevention, (b) physical safety, (c) patient preference, (d) clinical knowledge and beliefs, and (e) workload. Administration set replacement can be a complex task, particularly when patients have multiple infusions and incompatible medications. Nurses drew on perceptions of patient preference, as well as previous experience, knowledge of peer experts and local policies, to aid their decisions.

CONCLUSIONS

Nurses use clinical reasoning to balance patient safety and preferences with competing workplace demands when undertaking administration set replacement. Nurses rely on previous experience, hospital and medication manufacturer policies, and peer experts to guide their practice.

RELEVANCE TO CLINICAL PRACTICE

Nurses at times deviate from clinical guidelines in the interests of patient acuity, nurses' experience and workload. The findings of this study indicate nurses also balance considerations of patient preference and safety with these competing demands.

Skin complications associated with vascular access devices: A secondary analysis of 13 studies involving 10,859 devices

BACKGROUND

Vascular access devices are widely used in healthcare settings worldwide. The insertion of a vascular access device creates a wound, vulnerable to irritation, injury and infection. Vascular access-associated skin complications are frequently reported in the literature, however very little evidence is available regarding the incidence and risk factors of these conditions to inform practice and technology development.

OBJECTIVES

To estimate the incidence of vascular access-associated skin complications, and to identify patient, catheter and healthcare-related characteristics associated with skin complication development.

DESIGN

Secondary data analysis from 13 multi-centre randomised controlled trials and observational studies evaluating technologies and performance of vascular access devices in clinical settings between 2008 and 2017.

SETTINGS

Six hospitals (metropolitan and regional) in Queensland, Australia.

PARTICIPANTS

The 13 studies involved paediatric and adult participants, across oncology, emergency, intensive care, and general hospital settings. A total of 7669 participants with 10,859 devices were included, involving peripheral venous (n = 9933), peripheral arterial (n = 341), and central venous access (n = 585) devices.

ANALYSIS

Standardised study data were extracted into a single database. Clinical and demographic data were descriptively reported. Cox proportional hazards regression models (stratified by peripheral vs central) were used for time-to-event, per-device analyses to examine risk factors. Univariate associations were undertaken due to complexities with missing data in both outcomes and covariates, with p < 0.01 to reduce the effect of multiple comparisons.

RESULTS

Over 12% of devices were associated with skin complication, at 46.2 per 1000 catheter days for peripheral venous and arterial devices (95% confidence interval, CI 42.1-50.7), and 22.5 per 1000 catheter days for central devices (95% CI 16.5-306). The most common skin complications were bruising (peripheral n = 134, 3.7%; central n = 33, 6.8%), and swelling due to infiltration for peripheral devices (n = 296; 2.9%), and dermatitis for central devices (n = 13; 2.2%). The significant risk factors for these complications were predominantly related to device (e.g., skin tears associated with peripheral arterial catheters [hazard ratio, HR 16.0], radial insertion [HR 18.0] basilic insertion [HR 26.0])) and patient characteristics (e.g., poor skin integrity associated with increased risk of peripheral device bruising [HR 4.12], infiltration [HR 1.98], and skin tear [HR 48.4]), rather than management approaches.

CONCLUSIONS

Significant skin complications can develop during the life of peripheral and central vascular access devices, and these are associated with several modifiable and non-modifiable risk factors. Further research is needed to evaluate effectiveness technologies to prevent and treat skin complications associated with vascular access devices.

Pathophysiology of swallowing following oropharyngeal surgery for obstructive sleep apnea syndrome

BACKGROUND

Uvulopalatopharyngoplasty (UPPP) and coblation channeling of the tongue (CCT) are oropharyngeal surgeries used to treat obstructive sleep apnea syndrome. The extent to which UPPP and CCT affect pharyngeal swallow has not been determined. We therefore conducted a novel case series study employing high-resolution impedance manometry (HRIM) to quantify the swallowing-related biomechanics following UPPP and/or CCT surgery.

METHODS

Twelve patients who underwent UPPP+CCT or CCT only were assessed an average 2.5 years postsurgery. Swallow function data were compared with ten healthy controls. All patients completed the Sydney swallow questionnaire (SSQ). Pharyngeal pressure-flow analysis of HRIM recordings captured key distension, contractility and pressure-flow timing swallow parameters testing 5, 10, and 20 mL volumes of thin and thick fluid consistencies.

KEY RESULTS

Postoperative patients had more dysphagia symptoms with five returning abnormal SSQ scores. Swallowing was biomechanically altered compared to controls, consistent with diminished swallowing reserve, largely driven by elevated hypopharyngeal intrabolus pressure due to a reduced capacity to open the upper esophageal sphincter to accommodate larger volumes.

CONCLUSIONS & INFERENCES

Patients who have undergone UPPP and/or CCT surgery appear to have a deficiency in normal modulation of the swallowing mechanism and a reduced swallowing functional reserve. We speculate that these changes may become relevant in later life with the onset of age-related stressors to the swallowing mechanism. This case series strikes a note of caution that further studies are needed to determine the role of preoperative swallow assessment in patients undergoing UPPP and/or CCT surgery.

International Children's Advisory Network: A Multifaceted Approach to Patient Engagement in Pediatric Clinical Research

Pediatric youth advisory groups were created to provide insight and guidance to the clinical research community. Such efforts have become a priority and parallel the demand for patient-centered health care. While steps are being made to integrate the patient voice into research, there remains a lack of pediatric-specific engagement in the development of pharmaceuticals and in clinical research. For example, a significant number of children are still treated with medications that are not approved for use in this age group, due to a lack of clinical trials involving younger children and neonates. The American Academy of Pediatrics noted that physicians are faced with an ethical dilemma, as they must frequently either not treat children with potentially beneficial medications or treat them with medications based on adult studies or anecdotal empirical experience in children. By improving the approach to pediatric study design, indications for pediatric-specific therapies can be developed. We describe a structured organization with empowered youth and parents who are beginning to play a key role in the research process that suggests ways to improve pediatric research and for innovative medical products to be more "child friendly" and usable. We will also describe how investigators can engage the International Children's Advisory Network to obtain valuable youth perspectives on many aspects of clinical research and health care advocacy.

Sustainable entrepreneurship: another avenue for family business scholarship?

Purpose

The purpose of this paper is to review family businesses as a subset of sustainable entrepreneurship. It is intended that another avenue of scholarship for the growing interest in family businesses and their continuity across generations will be outlined.

Design/methodology/approach

Relevant journal articles were selected and broadly analysed to gather an understanding of the current state of existing sustainable entrepreneurship literature. The main themes extrapolated related to sustainable entrepreneurship and potential directions for future research.

Findings

Although sustainable entrepreneurship has been traditionally concentrated in the environmental and social responsibility literature, there are emerging paths where family businesses can be considered alongside community-based enterprise.

Research limitations/implications

The findings suggest that future research into sustaining family businesses across generations could be situated under sustainable entrepreneurship scholarship.

Originality/value

This paper presents a novel review and summary of recent literature at the juncture of family business and sustainable entrepreneurship. It is useful for directing scholars towards an avenue which has not traditionally had attention from family business researchers.

Validation of virtual-reality-based simulations for endoscopic sinus surgery

BACKGROUND

Virtual reality (VR) simulators provide an alternative to real patients for practicing surgical skills but require validation to ensure accuracy. Here, we validate the use of a virtual reality sinus surgery simulator with haptic feedback for training in Otorhinolaryngology - Head & Neck Surgery (OHNS).

METHODS

Participants were recruited from final-year medical students, interns, resident medical officers (RMOs), OHNS registrars and consultants. All participants completed an online questionnaire after performing four separate simulation tasks. These were then used to assess face, content and construct validity. anova with post hoc correlation was used for statistical analysis.

RESULTS

The following groups were compared: (i) medical students/interns, (ii) RMOs, (iii) registrars and (iv) consultants. Face validity results had a statistically significant (P < 0.05) difference between the consultant group and others, while there was no significant difference between medical student/intern and RMOs. Variability within groups was not significant. Content validity results based on consultant scoring and comments indicated that the simulations need further development in several areas to be effective for registrar-level teaching. However, students, interns and RMOs indicated that the simulations provide a useful tool for learning OHNS-related anatomy and as an introduction to ENT-specific procedures.

CONCLUSIONS

The VR simulations have been validated for teaching sinus anatomy and nasendoscopy to medical students, interns and RMOs. However, they require further development before they can be regarded as a valid tool for more advanced surgical training.

Paget's Disease of Bone: Progress Towards Remission and Prevention

Paget's disease of bone is a focal disorder of bone remodelling leading to areas of enlarged weakened bone manifesting with chronic pain, bone deformity, and fracture. Predominantly a disease of older adults, its prevalence is strongly linked to European ancestry. Pre-disposing factors include exposure to viruses such as measles and mutations in the SQSTM1 gene. PDB is diagnosed on plain radiograph, the extent of disease is delineated by radionuclide bone imaging, the degree of activity is quantified biochemically, and it is treated with a nitrogen-containing bisphosphonate, most effectively by a single intravenous infusion of zoledronate 5mg. Lifelong specialist follow-up is advocated because some patients require repeated infusions. Current clinical research is focusing on genetic factors in order to identify patients suitable for prevention.

Quality Heterostructures from Two-Dimensional Crystals Unstable in Air by Their Assembly in Inert Atmosphere

Many layered materials can be cleaved down to individual atomic planes, similar to graphene, but only a small minority of them are stable under ambient conditions. The rest react and decompose in air, which has severely hindered their investigation and potential applications. Here we introduce a remedial approach based on cleavage, transfer, alignment, and encapsulation of air-sensitive crystals, all inside a controlled inert atmosphere. To illustrate the technology, we choose two archetypal two-dimensional crystals that are of intense scientific interest but are unstable in air: black phosphorus and niobium diselenide. Our field-effect devices made from their monolayers are conductive and fully stable under ambient conditions, which is in contrast to the counterparts processed in air. NbSe2 remains superconducting down to the monolayer thickness. Starting with a trilayer, phosphorene devices reach sufficiently high mobilities to exhibit Landau quantization. The approach offers a venue to significantly expand the range of experimentally accessible two-dimensional crystals and their heterostructures.

Phylogenetic clustering of hepatitis C virus among people who inject drugs in Vancouver, Canada

Little is known about factors associated with hepatitis C virus (HCV) transmission among people who inject drugs (PWID). Phylogenetic clustering and associated factors were evaluated among PWID in Vancouver, Canada. Data were derived from the Vancouver Injection Drug Users Study. Participants who were HCV antibody-positive at enrolment and those with HCV antibody seroconversion during follow-up (1996 to 2012) were tested for HCV RNA and sequenced (Core-E2 region). Phylogenetic trees were inferred using maximum likelihood analysis and clusters were identified using ClusterPicker (90% bootstrap threshold, 0.05 genetic distance threshold). Factors associated with clustering were assessed using logistic regression. Among 655 eligible participants, HCV genotype prevalence was: G1a: 48% (n=313), G1b: 6% (n=41), G2a: 3% (n=20), G2b: 7% (n=46), G3a: 33% (n=213), G4a: <1% (n=4), G6a: 1% (n=8), G6e: <1% (n=1), and unclassifiable: 1% (n=9). The mean age was 36 years, 162 (25%) were female, and 164 (25%) were HIV+. Among 501 participants with HCV G1a and G3a, 31% (n=156) were in a pair/cluster. Factors independently associated with phylogenetic clustering included: age <40 (versus age≥40, adjusted odds ratio [AOR]=1.64; 95% confidence interval [CI] 1.03, 2.63), human immunodeficiency virus (HIV) infection (AOR=1.82; 95% CI 1.18, 2.81), HCV seroconversion (AOR=3.05; 95% CI 1.40, 6.66), and recent syringe borrowing (AOR 1.59; 95% CI 1.07, 2.36).

CONCLUSION

In this sample of PWID, one-third demonstrated phylogenetic clustering. Factors independently associated with phylogenetic clustering included younger age, recent HCV seroconversion, prevalent HIV infection, and recent syringe borrowing. Strategies to enhance the delivery of prevention and/or treatment strategies to those with HIV and recent HCV seroconversion should be explored, given an increased likelihood of HCV transmission in these subpopulations.

Association between vitamin D status and physical function in the severely obese

CONTEXT

Mortality is 85% higher in severely obese subjects (body mass index [BMI] > 40 kg/m(2)) than in subjects with a healthy BMI; poor physical function may be contributory. Hypovitaminosis D is common in obese subjects and is associated with physical dysfunction in the elderly.

OBJECTIVE

We determined the relationship between vitamin D status and physical function in severely obese subjects.

DESIGN, SETTING, AND PATIENTS

We conducted a clinic-based, cross-sectional study of severely obese subjects. Participants were stratified into three groups according to the Institute of Medicine (IOM) vitamin D status categorization.

MAIN OUTCOME MEASURES

We compared levels of self-reported activity and times taken to walk 500 m and to ascend and descend a 17-cm step 50 times.

RESULTS

We recruited 252 subjects (age, 43.7 ± 11.2 y; BMI, 50.7 ± 9.7 kg/m(2)); 25-hydroxyvitamin D (25OHD) concentrations were less than 30 nmol/L in 109 participants. Participants with a 25OHD > 50 nmol/L, compared to those with a 25OHD < 30 nmol/L, had the highest activity levels (3.1 ± 3.4 h/wk versus 1.5 ± 2.5 h/wk; P = .015) and the shortest 500-m walk times (6.2 ± 1.1 min versus 7.4 ± 1.5 min; P = .003). Serum 25OHD concentrations had a weakly positive association with activity level (r = 0.19; P = .008) and a moderately negative association with 500-m walk time (r = -0.343; P < .001).

CONCLUSIONS

Vitamin D status had a significant relationship with physical activity and physical function in this cohort of severely obese subjects. Low activity levels are likely to perpetuate the problem of hypovitaminosis D due to less time spent outdoors. Studies exploring the effects of vitamin D supplementation in this population are warranted.

Predicting coronary heart disease in remote settings: a prospective, cross-sectional observational study

BACKGROUND

Coronary heart disease (CHD) places a major burden on the Australian health care system. Determining the likelihood of CHD in a patient presenting with chest pain can be particularly difficult in a remote setting where access to transportation and specialised investigations including myocardial stress studies and coronary angiography can be difficult and delayed. The objective is to develop a predictive model for determining the risk of CHD, including the value of high sensitivity C-reactive protein (hsCRP), in patients presenting with chest pain with a particular emphasis on resources and information likely to be available in a remote primary health care setting.

METHODS

A prospective, cross-sectional observational study of patients with no prior diagnosis of CHD presenting to a specialist chest pain assessment clinic at Cairns Hospital from November 2012 to May 2013.

RESULTS

Out of the 163 participants included in the study analyses, a total of 38 were classified as CHD likely (23.3% (95% CI 17.1-30.6)). Logistic regression modelling identified two factors that were independently associated with likely CHD, namely the presence of typical chest pain (OR 83.7 (95% CI 21.7-322.1)) and an abnormal baseline ECG (OR 12.8 (95% CI 1.9-86.0)).

CONCLUSION

In this study, it was demonstrated that the presence of typical chest pain and an abnormal resting ECG, remain the cornerstone of predicting a subsequent diagnosis of CHD. This information is easily accessible in remote primary health care and should be utilised to expedite assessment in patients presenting with symptoms suggestive of CHD.

Performance of HIV-1 drug resistance testing at low-level viremia and its ability to predict future virologic outcomes and viral evolution in treatment-naive individuals

BACKGROUND

Low-level viremia (LLV; human immunodeficiency virus [HIV-1] RNA 50-999 copies/mL) occurs frequently in patients receiving antiretroviral therapy (ART), but there are few or no data available demonstrating that HIV-1 drug resistance testing at a plasma viral load (pVL) <1000 copies/mL provides potentially clinically useful information. Here, we assess the ability to perform resistance testing by genotyping at LLV and whether it is predictive of future virologic outcomes in patients beginning ART.

METHODS

Resistance testing by genotyping at LLV was attempted on 4915 plasma samples from 2492 patients. A subset of previously ART-naive patients was analyzed who achieved undetectable pVL and subsequently rebounded with LLV (n = 212). A genotypic sensitivity score (GSS) was calculated based on therapy and resistance testing results by genotyping, and stratified according to number of active drugs.

RESULTS

Eighty-eight percent of LLV resistance assays produced useable sequences, with higher success at higher pVL. Overall, 16 of 212 (8%) patients had pretherapy resistance. Thirty-eight of 196 (19%) patients without pretherapy resistance evolved resistance to 1 or more drug classes, primarily the nucleoside reverse transcriptase (14%) and/or nonnucleoside reverse transcriptase (9%) inhibitors. Patients with resistance at LLV (GSS <3) had a 2.1-fold higher risk of virologic failure (95% confidence interval, 1.2- to 3.7-fold) than those without resistance (P = .007). Progressively lower GSS scores at LLV were associated with a higher increase in pVL over time (P < .001). Acquisition of additional resistance mutations to a new class of antiretroviral drugs during LLV was not found in a subset of patients.

CONCLUSIONS

Routine HIV-1 genotyping of LLV samples can be performed with a reasonably high success rate, and the results appear predictive of future virologic outcomes.

Changes in human dendritic cell number and function in severe obesity may contribute to increased susceptibility to viral infection

Dendritic cells (DCs) are key immune sentinels linking the innate and adaptive immune systems. DCs recognise danger signals and initiate T-cell tolerance, memory and polarisation. They are critical cells in responding to a viral illness. Obese individuals have been shown to have an impaired response to vaccinations against virally mediated conditions and to have an increased susceptibility to multi-organ failure in response to viral illness. We investigated if DCs are altered in an obese cohort (mean body mass index 51.7±7.3 kg m(-2)), ultimately resulting in differential T-cell responses. Circulating DCs were found to be significantly decreased in the obese compared with the lean cohort (0.82% vs 2.53%). Following Toll-like receptor stimulation, compared with lean controls, DCs generated from the obese cohort upregulated significantly less CD83 (40% vs 17% mean fluorescence intensity), a molecule implicated in the elicitation of T-cell responses, particularly viral responses. Obese DCs produced twofold more of the immunosuppressive cytokine interleukin (IL)-10 than lean controls, and in turn stimulated fourfold more IL-4-production from allogenic naive T cells. We conclude that obesity negatively impacts the ability of DCs to mature and elicit appropriate T-cell responses to a general stimulus. This may contribute to the increased susceptibility to viral infection observed in severe obesity.

SME family business innovation: exploring new combinations

Purpose

– Continued research around innovation within small- and medium-sized enterprises (SME) family businesses is needed to better understand the influence of specific resources and capabilities that might promote and/or constrain entrepreneurial activities. The purpose of this paper is to develop an organising framework investigating SME family business innovation drawing on a Schumpeterian understanding of innovation as the introduction of new combinations.

Design/methodology/approach

– Four guiding principles are developed and applied to an illustrative case study of an entrepreneurial family business that highlights the usefulness of complexity thinking for understanding innovation.

Findings

– NZ Sock provides a rich illustrative case study to highlight how principles of complexity thinking along with Schumpeterian notions of innovation can usefully inform the authors’ understanding of entrepreneurial SME family businesses. The proposed guiding principles offered are borne out in application to the illustrative case example.

Research limitations/implications

– The findings suggest that complexity thinking and a Schumpeterian lens can usefully inform and extend the authors’ understanding of innovation within entrepreneurial SME family businesses. Further research would benefit from exploring the guiding principles proposed in other entrepreneurial SME family businesses to further substantiate this field of inquiry.

Practical implications

– Principles of complexity thinking may provide additional understanding and insight for SME family business members needing to innovate and adapt to ever-changing operating environments.

Originality/value

– Innovation is critical to the long-term survival and success of such firms; yet, to date little theoretical contribution and research has been offered in the field of innovation within the context of SME family businesses. Complex adaptive systems provide a lens from which to understand such businesses and that that a complexity framework helpfully allows attention to be given to such phenomena as emergence, adaptability and combinations through which innovation outcomes and processes may be understood. This paper offers four guiding principles that can be further tested and refined.

Serum prolactin concentration at presentation of non-functioning pituitary macroadenomas

OBJECTIVE

Serum PRL levels at presentation may be useful in distinguishing between disconnection hyperprolactinemia in non-secretory pituitary adenomas and prolactinomas in order to guide appropriate therapy; however, there is a debate regarding the discriminatory PRL thresholds. We aimed to examine PRL concentrations at presentation in a cohort of histologically proven non-functioning pituitary adenomas (NFPA).

DESIGN AND METHODS

Retrospective case note analysis was performed. Clinical, biochemical, histopathological and radiological data were recorded and analyzed. Complete data were available for 250 subjects with NFPA.

RESULTS

Of the study population, 44.8% were hyperprolactinemic at presentation, 55.3% of whom were female. Of those with hyperprolactinemia, 73.2% had PRL<1000 mIU/l on presentation, 24.1% had PRL between 1000 and 1999 mIU/l. Only 2.7% (no.=3 females, 1.2% whole cohort) had PRL>2000 mIU/l (94.3 ng/ml), 2 of whom were pregnant. No male subject and no subjects with an intrasellar macroadenoma had serum PRL>1000 mIU/l (47.2 ng/ml). Overall, serum PRL was not higher among 43 subjects taking medications known to raise PRL.

CONCLUSIONS

Our data support recent evidence that the serum PRL concentration is rarely >1000 mIU/l in males, or >2000 mIU/l in females, with non-functioning macroadenomas and that, once other contributing factors to the hyperprolactinemia have been excluded, a trial of dopamine agonist therapy for such lesions is indicated.

Role of riverine colloids in macronutrient and metal partitioning and transport, along an upland-lowland land-use continuum, under low-flow conditions

An assessment is made of the role of riverine colloids in macronutrient (nitrogen, phosphorus and carbon), metal and trace element partitioning and transport, for five rivers in the Ribble and Wyre catchments in north-western England, under baseflow/near-baseflow conditions. Cross-flow ultrafiltration was used to separate colloidal (<0.45 µm >1 kDa) and truly dissolved (<1 kDa) fractions from river water. Clear patterns were observed, along the upland-lowland land use continuum, in the partitioning and transport of macronutrients and metals between the colloidal, truly dissolved and acid-available particulate (>0.45 μm, suspended) fractions. Of these operationally-defined fractions measured, colloids were generally more important for both macronutrient and metal transport in the upland than in the lowland rivers. The results suggest that organic moieties in truly dissolved form from sewage effluent may have a greater capacity to chelate metals. Organic-rich colloids in the upland moorlands and metal oxide colloidal precipitates in the industrial rivers had a higher capacity for binding metals than the colloidal fractions in the urban and agricultural lowland rivers. Aggregation of these colloids may provide an important mechanism for formation of larger suspended particulates, accounting for a higher degree of metal enrichment in the acid-available particulate fractions of the upland moorland and lowland industrial rivers, than in the lowland agricultural and urban rivers. This mechanism of transfer of contaminants to larger aggregates via colloidal intermediates, known as 'colloidal pumping' may also provide a mechanism for particulate P formation and the high proportion of P being transported in the particulate fraction in the uplands. The cross-flow ultrafiltration data also allowed refinement of partition coefficients, by accounting for colloids within the solids phase and replacing the filtered (<0.45 μm) fraction with the truly dissolved (<1 kDa) concentrations. These provided a clearer description of the controls on metal and P partitioning along the upland-lowland continuum.