Reference values for leg effort during incremental cycle ergometry in non-trained healthy men and women, aged 19-85

Heightened sensation of leg effort contributes importantly to poor exercise tolerance in patient populations. We aim to provide a sex- and age-adjusted frame of reference to judge symptom's normalcy across progressively higher exercise intensities during incremental exercise. Two-hundred and seventy-five non-trained subjects (130 men) aged 19-85 prospectively underwent incremental cycle ergometry. After establishing centiles-based norms for Borg leg effort scores (0-10 category-ratio scale) versus work rate, exponential loss function identified the centile that best quantified the symptom's severity individually. Peak O2 uptake and work rate (% predicted) were used to threshold gradually higher symptom intensity categories. Leg effort-work rate increased as a function of age; women typically reported higher scores at a given age, particularly in the younger groups (p < 0.05). For instance, "heavy" (5) scores at the 95th centile were reported at ~200 W (<40 years) and ~90 W (≥70 years) in men versus ~130 W and ~70 W in women, respectively. The following categories of leg effort severity were associated with progressively lower exercise capacity: ≤50th ("mild"), >50th to <75th ("moderate"), ≥75th to <95th ("severe"), and ≥ 95th ("very severe") (p < 0.05). Although most subjects reporting peak scores <5 were in "mild" range, higher scores were not predictive of the other categories (p > 0.05). This novel frame of reference for 0-10 Borg leg effort, which considers its cumulative burden across increasingly higher exercise intensities, might prove valuable to judging symptom's normalcy, quantifying its severity, and assessing the effects of interventions in clinical populations.

Impact of myocardial perfusion and coronary calcium on medical management for coronary artery disease

AIMS

Single-photon emission computed tomography (SPECT) myocardial perfusion imaging (MPI) remains one of the most widely used imaging modalities for the diagnosis and prognostication of coronary artery disease (CAD). Despite the extensive prognostic information provided by MPI, little is known about how this influences the prescription of medical therapy for CAD. We evaluated the relationship between MPI with computed tomography (CT) attenuation correction and prescription of acetylsalicylic acid (ASA) and statins.

METHODS AND RESULTS

We performed a retrospective analysis of consecutive patients who underwent SPECT MPI at a single centre between 2015 and 2021. Myocardial perfusion abnormalities and coronary calcium burden were assessed, with attenuation correction imaging 77.8% of patients. Medication prescriptions before and within 180 days after the test were compared. Associations between abnormal perfusion and calcium burden with ASA and statin prescription were assessed using multivariable logistic regression. In total, 9908 patients were included, with a mean age 66.8 ± 11.7 years and 5337 (53.9%) males. The prescription of statins increased more in patients with abnormal perfusion (increase of 19.2 vs. 12.0%, P < 0.001). Similarly, the presence of extensive CAC led to a greater increase in statin prescription compared with no calcium (increase 12.1 vs. 7.8%, P < 0.001). In multivariable analyses, ischaemia and coronary artery calcium were independently associated with ASA and statin prescription.

CONCLUSION

Abnormal MPI testing was associated with significant changes in medical therapy. Both calcium burden and perfusion abnormalities were associated with increased prescriptions of medical therapy for CAD.

Chitosan Scaffolds as Microcarriers for Dynamic Culture of Human Neural Stem Cells

Human neural stem cells (hNSCs) possess remarkable potential for regenerative medicine in the treatment of presently incurable diseases. However, a key challenge lies in producing sufficient quantities of hNSCs, which is necessary for effective treatment. Dynamic culture systems are recognized as a powerful approach to producing large quantities of hNSCs required, where microcarriers play a critical role in supporting cell expansion. Nevertheless, the currently available microcarriers have limitations, including a lack of appropriate surface chemistry to promote cell adhesion, inadequate mechanical properties to protect cells from dynamic forces, and poor suitability for mass production. Here, we present the development of three-dimensional (3D) chitosan scaffolds as microcarriers for hNSC expansion under defined conditions in bioreactors. We demonstrate that chitosan scaffolds with a concentration of 4 wt% (4CS scaffolds) exhibit desirable microstructural characteristics and mechanical properties suited for hNSC expansion. Furthermore, they could also withstand degradation in dynamic conditions. The 4CS scaffold condition yields optimal metabolic activity, cell adhesion, and protein expression, enabling sustained hNSC expansion for up to three weeks in a dynamic culture. Our study introduces an effective microcarrier approach for prolonged expansion of hNSCs, which has the potential for mass production in a three-dimensional setting.

3D Porous Scaffold-Based High-Throughput Platform for Cancer Drug Screening

Natural polymer-based porous scaffolds have been investigated to serve as three-dimensional (3D) tumor models for drug screening owing to their structural properties with better resemblance to human tumor microenvironments than two-dimensional (2D) cell cultures. In this study, a 3D chitosan-hyaluronic acid (CHA) composite porous scaffold with tunable pore size (60, 120 and 180 µm) was produced by freeze-drying and fabricated into a 96-array platform for high-throughput screening (HTS) of cancer therapeutics. We adopted a self-designed rapid dispensing system to handle the highly viscous CHA polymer mixture and achieved a fast and cost-effective large-batch production of the 3D HTS platform. In addition, the adjustable pore size of the scaffold can accommodate cancer cells from different sources to better mimic the in vivo malignancy. Three human glioblastoma multiforme (GBM) cell lines were tested on the scaffolds to reveal the influence of pore size on cell growth kinetics, tumor spheroid morphology, gene expression and dose-dependent drug response. Our results showed that the three GBM cell lines showed different trends of drug resistance on CHA scaffolds of varying pore size, which reflects the intertumoral heterogeneity across patients in clinical practice. Our results also demonstrated the necessity to have a tunable 3D porous scaffold for adapting the heterogeneous tumor to generate the optimal HTS outcomes. It was also found that CHA scaffolds can produce a uniform cellular response (CV < 0.15) and a wide drug screening window (Z' > 0.5) on par with commercialized tissue culture plates, and therefore, can serve as a qualified HTS platform. This CHA scaffold-based HTS platform may provide an improved alternative to traditional 2D-cell-based HTS for future cancer study and novel drug discovery.

The impact of the COVID-19 pandemic on the provision & utilisation of primary health care services in Goma, Democratic Republic of the Congo, Kambia district, Sierra Leone & Masaka district, Uganda

INTRODUCTION

This study aimed to determine whether the COVID-19 pandemic had an impact on essential primary healthcare services at public primary healthcare facilities.

METHODS

The number of weekly consultations for antenatal care (ANC), outpatient (OPD), immunisations (EPI), family planning (FP) and HIV services, between January 2018 and December 2020, were collected from 25 facilities in Masaka district, Uganda, 21 in Goma, and 29 in Kambia district, Sierra Leone. Negative binomial regression models accounting for clustering and season were used to analyse changes in activity levels between 2018, 2019 and 2020.

RESULTS

In Goma, we found no change in OPD, EPI or ANC consultations, FP was 17% lower in March-July 2020 compared to 2019, but this recovered by December 2020. New diagnoses of HIV were 34% lower throughout 2020 compared to 2019. In Sierra Leone, compared to the same periods in 2019, facilities had 18-29% fewer OPD consultations throughout 2020, and 27% fewer DTP3 doses in March-July 2020. There was no evidence of differences in other services. In Uganda there were 20-35% fewer under-5 OPD consultations, 21-66% fewer MCV1 doses, and 48-51% fewer new diagnoses of HIV throughout 2020, compared to 2019. There was no difference in the number of HPV doses delivered.

CONCLUSIONS

The level of disruption varied across the different settings and qualitatively appeared to correlate with the strength of lockdown measures and reported attitudes towards the risk posed by COVID-19. Mitigation strategies such as health communications campaigns and outreach services may be important to limit the impact of lockdowns on primary healthcare services.

A TNR Frameshift Variant in Weimaraner Dogs with an Exercise-Induced Paroxysmal Movement Disorder

BACKGROUND

Some paroxysmal movement disorders remain without an identified genetic cause.

OBJECTIVES

The aim was to identify the causal genetic variant for a paroxysmal dystonia-ataxia syndrome in Weimaraner dogs.

METHODS

Clinical and diagnostic investigations were performed. Whole genome sequencing of one affected dog was used to identify private homozygous variants against 921 control genomes.

RESULTS

Four Weimaraners were presented for episodes of abnormal gait. Results of examinations and diagnostic investigations were unremarkable. Whole genome sequencing revealed a private frameshift variant in the TNR (tenascin-R) gene in an affected dog, XM_038542431.1:c.831dupC, which is predicted to truncate more than 75% of the open read frame. Genotypes in a cohort of 4 affected and 70 unaffected Weimaraners showed perfect association with the disease phenotype.

CONCLUSIONS

We report the association of a TNR variant with a paroxysmal dystonia-ataxia syndrome in Weimaraners. It might be relevant to include sequencing of this gene in diagnosing humans with unexplained paroxysmal movement disorders. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

External validation of the CRAX2MACE model

BACKGROUND

Single-photon emission computed tomography (SPECT) myocardial perfusion is frequently used to predict risk of major adverse cardiovascular events (MACE). We performed an external validation of the CRAX2MACE score, developed to estimate 2-year risk of MACE in patients with suspected coronary artery disease (CAD).

METHODS

Patients who underwent clinically indicated SPECT with available follow-up for MACE were included (N = 2,985). The prediction performance for MACE (revascularization, myocardial infarction, or death) within 2 years for CRAX2MACE was compared with stress and ischemic total perfusion deficit (TPD) using area under the receiver operating characteristic curve (AUC). Calibration was assessed with calibration plots, Brier score, and the Hosmer-Lemeshow test.

RESULTS

MACE occurred within 2 years in 243 (8.1%) patients. The AUC for CRAX2MACE (0.710, 95% CI 0.677-0.743) was significantly higher compared to stress TPD (AUC 0.669, 95% CI 0.632-0.706, P = .010) and ischemic TPD (AUC 0.664, 95% CI 0.627-0.700, P < .001). The model had acceptable goodness-of-fit (P = .103) and was well-calibrated with Brier score of 0.071.

CONCLUSION

CRAX2MACE had higher predictive performance for 2-year MACE than quantitative perfusion in an external population. The current model is simple to use and could be implemented to assist physicians when estimating patient risk.

Optimising the use of physiotherapy resources after manipulation under anaesthetic for frozen shoulder

INTRODUCTION

Manipulation under anaesthetic (MUA) is a successful treatment for frozen shoulder (FS), and the recovery period and recurrence rates may be reduced by postoperative physiotherapy. This study evaluates two physiotherapy pathways for patients undergoing MUA for FS.

METHODS

Between 2016 and 2018, 248 age- and sex-matched patients presented to either a NHS secondary care upper limb service or the lead author's independent practice with a diagnosis of FS. The patients had differential access to postprocedure physiotherapy based on which service they presented to. In Group 1, physiotherapy advice only was given to the patient. In Group 2, supervised hydrotherapy and physiotherapy occurred postoperatively. Pre- and postprocedure Oxford Shoulder Scores (OSS) were collected for each group. Analysis of covariance (ANCOVA) was used to measure the effect of physiotherapy on postoperative OSS.

RESULTS

Group 2 showed a significantly greater improvement in postprocedure OSS when compared with Group 1 (18.2 vs 16.7) p<0.001). The estimated maximum effect of physiotherapy on postoperative OSS was an increase of 3.2.

CONCLUSION

Following MUA for FS, a statistically significant increase in OSS was detected in patients receiving postprocedure physiotherapy compared with advice alone. There was no difference in recurrence rates. The increase in OSS (3.2) is below the minimal clinically important difference, raising questions regarding the relative importance of postprocedure physiotherapy in a resource-limited environment.

High-Throughput Dispensing of Viscous Solutions for Biomedical Applications

Cells cultured in three-dimensional scaffolds express a phenotype closer to in vivo cells than cells cultured in two-dimensional containers. Natural polymers are suitable materials to make three-dimensional scaffolds to develop disease models for high-throughput drug screening owing to their excellent biocompatibility. However, natural polymer solutions have a range of viscosities, and none of the currently available liquid dispensers are capable of dispensing highly viscous polymer solutions. Here, we report the development of an automated scaffold dispensing system for rapid, reliable, and homogeneous creation of scaffolds in well-plate formats. We employ computer-controlled solenoid valves to regulate air pressure impinging upon a syringe barrel filled with scaffold solution to be dispensed. Automated dispensing of scaffold solution is achieved via a programmable software interface that coordinates solution extrusion and the movement of a dispensing head. We show that our pneumatically actuated dispensing system can evenly distribute high-viscosity, chitosan-based polymer solutions into 96- and 384-well plates to yield highly uniform three-dimensional scaffolds after lyophilization. We provide a proof-of-concept demonstration of high-throughput drug screening by culturing glioblastoma cells in scaffolds and exposing them to temozolomide. This work introduces a device that can hasten the creation of three-dimensional cell scaffolds and their application to high-throughput testing.

Ventilatory neural drive in chronically hypercapnic patients with COPD: effects of sleep and nocturnal noninvasive ventilation

Sleep brings major challenges for the control of ventilation in humans, particularly the regulation of arterial carbon dioxide pressure (P _aCO2 ). In patients with COPD, chronic hypercapnia is associated with increased mortality. Therefore, nocturnal high-level noninvasive positive-pressure ventilation (NIV) is recommended with the intention to reduce P _aCO2 down to normocapnia. However, the long-term physiological consequences of P _aCO2 "correction" on the mechanics of breathing, gas exchange efficiency and resulting symptoms (i.e. dyspnoea) remain poorly understood. Investigating the influence of sleep on the neural drive to breathe and its translation to the mechanical act of breathing is of foremost relevance to create a solid rationale for the use of nocturnal NIV. In this review, we critically discuss the mechanisms by which sleep influences ventilatory neural drive and mechanical consequences in healthy subjects and hypercapnic patients with advanced COPD. We then discuss the available literature on the effects of nocturnal NIV on ventilatory neural drive and respiratory mechanics, highlighting open avenues for further investigation.

Phenotypic characterisation of paroxysmal dyskinesia in Sphynx cats

OBJECTIVES

The aim of this study was to identify the phenotypic features of a paroxysmal dyskinesia observed in Sphynx cats.

METHODS

The owners of affected Sphynx cats were invited to provide video footage of abnormal episodes for review. Those that demonstrated episodes consistent with paroxysmal dyskinesia were then invited to complete an online questionnaire designed to allow further characterisation.

RESULTS

Ten Sphynx cats were included in the study. All affected cats were <4 years of age at the onset of the episodes (range 0.5-4.0). The episodes had a duration of <5 mins in 9/10 cats (range 0.5-10), while episode frequency was variable between and within individual cats. The episodes were characterised by impaired ambulation due to muscle hypertonicity, most commonly affecting the hips and pelvic limbs (9/10) and shoulders and thoracic limbs (8/10). The head and neck (6/10), tail (5/10), and back and abdomen (3/10) were also involved in some cats. Sudden movement, excitement and stress were identified as possible triggers for the episodes in three cats. Therapeutic intervention was not attempted in 7/10 cases, although two cats were reported to become free of the episodes while receiving acetazolamide. The two cats that were followed beyond 2 years from onset entered spontaneous remission. None of the owners believed that the abnormal episodes had affected the quality of life of their cat.

CONCLUSIONS AND RELEVANCE

The phenotype of paroxysmal dyskinesia in Sphynx cats presented in this study appears to share similarities with paroxysmal kinesigenic dyskinesia described in human classification systems. Some cats appear to achieve episode freedom spontaneously. Subsequent research should focus on evaluating response to treatment and determining an underlying genetic cause.

Patient, Caregiver, and Provider Perspectives on Improving Information Delivery in Hemodialysis: A Qualitative Study

Background

Patients with kidney failure are exposed to a surfeit of new information about their disease and treatment, often resulting in ineffective communication between patients and providers. Improving the amount, timing, and individualization of information received has been identified as a priority in in-center hemodialysis care.

Objective

To describe and explicate patient, caregiver, and health care provider perspectives regarding challenges and solutions to information transfer in clinical hemodialysis care.

Design

In this multicenter qualitative study, we gathered perspectives of patients, their caregivers, and health care providers conducted through focus groups and interviews.

Setting

Five Canadian hemodialysis centers: Calgary, Edmonton, Winnipeg, Ottawa, and Halifax.

Participants

English-speaking adults receiving in-center hemodialysis for longer than 6 months, their caregivers, and hemodialysis health care providers.

Methods

Between May 24, 2017, and August 16, 2018, data collected through focus groups and interviews with hemodialysis patients and their caregivers subsequently informed semi-structured interviews with health care providers. For this secondary analysis, data were analyzed through an inductive thematic analysis using grounded theory, to examine the data more deeply for overarching themes.

Results

Among 82 patients/caregivers and 31 healthcare providers, 6 main themes emerged. Themes identified from patients/caregivers were (1) overwhelmed at initiation of hemodialysis care, (2) need for peer support, and (3) improving comprehension of hemodialysis processes. Themes identified from providers were (1) time constraints with patients, (2) relevance of information provided, and (3) technological innovations to improve patient engagement.

Limitations

Findings were limited to Canadian context, English speakers, and individuals receiving hemodialysis in urban centers.

Conclusions

Participants identified challenges and potential solutions to improve the amount, timing, and individualization of information provided regarding in-center hemodialysis care, which included peer support, technological innovations, and improved knowledge translation activities. Findings may inform the development of interventions and strategies aimed at improving information delivery to facilitate patient-centered hemodialysis care.

1266 Digital Rectal Examination: Do You Still Put Your Foot in It If You Don’t Put Your Finger in It?

Introduction

Most surgical trainees are familiar with the aphorism ‘if you don’t put your finger in it, you put your foot in it’, with regards to digital rectal examination (DRE). This commonly taught maxim, attributed to Bailey and Love in their Short Practice of Surgery, was coined to highlight the folly of neglecting DRE in patients with histories suggestive of malignant anorectal pathology. However, data are lacking on the diagnostic yield of DRE for detecting anorectal cancer in patients with lower gastrointestinal bleeding (LGIB), whilst advances in biomarker and imaging technology beg the question: is there still a role for DRE in the assessment of patients with LGIB?

Method

We designed a clinical coding search strategy to identify all adult patients with acute LGIB referred to general surgery at a UK university hospital from January to July 2020. Electronic patient records were interrogated to identify history and examination findings, diagnoses and clinical outcomes.

Results

169 patients (median age 63 (16-94) years, 54.4% male) were identified, 74.6% (126/169) with bright red bleeding, 23.7% (40/169) with altered blood and 1.8% (3/169) with melaena. DRE was performed in 91.1% (154/169) of patients, identifying blood in 42.9% (66/154) of cases and suspicious lesions, which were subsequently confirmed as anorectal malignancy, in 1.3% (2/154).

Conclusions

DRE represents a possibly stigmatising and uncomfortable examination for patients and clinicians alike. These data support the utility of DRE in patients with LGIB and may inform the discussion at the bedside to facilitate the timely diagnosis of anorectal malignancy.

1419 Targeted Use of Physiotherapy Resources in The COVID Era: How Does Face to Face Physiotherapy Compare with Simple Advice Sheets After Manipulation Under Anaesthetic for Frozen Shoulder?

Introduction

This study compares two pathways for patients undergoing MUA for FS, one where physiotherapy advice is only given to the patient (Group 1), and the other where supervised hydrotherapy and physiotherapy occur post operatively (Group 2).

Method

A descriptive analysis of pre- and post-operative Oxford Shoulder Scores and change scores were performed. Analysis of covariance (ANCOVA) was used to measure the effect of physiotherapy on post-operative OSS, with pre-operative OSS as the only covariate.

Results

The results for post-operative OSS were significantly greater for Group 2 than for Group 1 (40.7 for NHS and 44.7 for private, improvement of 17.32 for NHS and 18.23 for Private). The effect of physiotherapy was significant (p &lt; 0.001). The estimated effect of physiotherapy on postoperative OSS was an increase of 3.2 (95% confidence interval 1.5 – 4.8).

Conclusions

We detected a statistically significant increase in post-operative OSS in patients treated for frozen shoulder with MUA + physiotherapy compared with patients receiving MUA plus advice alone. These results suggest that physiotherapy does confer a real benefit, however the increased OSS is below the clinically significant level. Therefore, in a resource poor environment, such as may exist during and after COVID in many health care systems, MUA plus physio advice alone gives an excellent outcome for the treatment of FS.

Household economic impact of road traffic injury versus routine emergencies in a low-income country

INTRODUCTION

Road traffic injuries (RTIs) are increasing and have disproportionate impact on residents of low- and middle-income countries (LMICs) where 90% of deaths occur. RTIs are a leading cause of death for those aged 15 - 29 years with costs estimated to be up to 3% of GDP. Despite this fact, little primary research has been done on the household economic impact of these events.

METHODS

From July to October 2016, 860 consecutive emergency department patients were enrolled and followed up at 6-8 weeks to assess the household financial impacts of these emergency presentations. At follow-up, patients were queried regarding health status, lost wages or schooling, household costs incurred due to their injury or illness, and assets sold.

RESULTS

860 patients were enrolled and 675 patients (78%) completed follow-up surveys. Of those, 660 had a confirmed reason for visit - 303 (45%) road traffic injuries, 357 (53%) other emergency presentations (non-RTI) - encompassing medical presentations and other types of injury, and reason for visit was missing for 15 patients (2%). More than 90% of RTI patients were working or in school prior to their injury. In the economically productive ages (15-44 years) RTI predominated (70%) vs non-RTI (39%). RTI patients were more likely to report residual disability (78.2% RTI vs 68.1% non-RTI, p=0.004). All emergency patients reported difficulty paying for basic needs (food, housing and medical expenses). More than ⅓ of emergency patients reported having to sell assets in order to meet basic needs after their illness or injury. Despite similar hospital costs and fewer lost days of work for both patients and caregivers, the mean financial impact on households of RTI patients was 37% more than for non-RTI patients. These costs equalled between 6-16 weeks of income for patients based on their occupation type and median reported pre-hospitalization income.

DISCUSSION

Ugandan emergency care patients suffered significant personal and household economic hardship. In addition to the need for policy and infrastructural changes to improve road safety, these findings highlight the need for basic emergency care systems to secure economic gains in vulnerable households and prevent medical impoverishment of marginal communities.

Spectral characterization of flash and high flux x-ray radiographic sources with a magnetic Compton spectrometer

In this work, we present a new analysis method applied to revitalize permanent magnet Compton spectrometers used to measure photon energy spectra in the MeV range. The inversion of the measured electron distribution to determine the original photon distribution is achieved via a method of consistent coupled radiation transport and magnetic field mapping of the input photon spectra to the measured electron distribution. The method of linear least squares was used to perform the unfolding of the electron distribution to the initial photon spectra, without any assumptions made regarding the electron distribution. We present an application of this method to data from a nominal 19.4 MeV flash radiographic source (the first axis of the Dual Axis Radiographic Hydro-Test Facility) capable of generating 500 R @ 1 m in ∼60 ns and a medical therapy source (a Scanditronix M22, Microtron) capable of variable energies with nominal endpoints of 6, 10, 15, and 20 MeV and an output of ∼1000-2000 R/min @ 1 m. The results provide agreement between the modeled and unfolded experimentally measured photon spectra as quantified by statistical tests, from 1.5 to 20 MeV. Experimental results are presented as well as a discussion of the novel MCNP6-based simulations and methods for reconstruction of the spectra.

Low-Level Determination of Mutagenic Nitrosamine Impurities in Drug Substances by LC–MS/MS

Since the detection of N-nitrosodimethylamine (NDMA) in a batch of valsartan in 2018, at levels exceeding ICH acceptable intake limits for mutagenic impurities, the analysis of nitrosamines has become an intense focus point for the pharmaceutical industry. The identification and low-level determination of nitrosamines in potentially affected materials is challenging and requires the application of highly sensitive analytical techniques. This article reviews the chronological development of the story and the regulatory landscape that has evolved. It will then discuss the development of analytical methods for the determination of a series of nitrosamines referenced by regulatory authorities, demonstrating separation of these compounds from the active pharmaceutical ingredient (API) and looking at how mass spectrometry (MS) can be applied to ensure that the required detection limits can be reached.

Does time since injury and duration matter in the benefits of physical therapy treatment for concussion?

Objective

To determine if there are differences in post-concussion symptom levels depending on 1) when physical therapy treatment is begun after the concussion and 2) the length of treatment.

Method

Retrospective chart review yielded 202 patients who sustained concussions and were referred for physical therapy. Participants/patients were assigned to independent groups based on time elapsed between concussion and physical therapy (0–14, 15–30, 31–60, 61–120, 121–365 days), and on months spent in treatment (1–4). Pre- and post- treatment scores were documented for the following measures: Sport Concussion Assessment Tool (SCAT), Convergence Insufficiency Symptom Survey (CISS), Dizziness Handicap Inventory (DHI), and Modified Clinical Test of Sensory Interaction on Balance (mCTSIB) using ANOVAs, with a Bonferroni-corrected p-value of p < .005.

Results

All patients demonstrated improvements with treatment, with no significant differences in outcomes for time elapsed since injury (SCAT Symptom Score ( p = .80), SCAT Symptom Severity Score ( p = .97), CISS ( p = .61), DHI ( p = .65), mCTSIB ( p = .13)); or for months in treatment (SCAT Symptom Score ( p = .23), SCAT Symptom Severity Score ( p = .04), CISS ( p = .41), DHI ( p = .37), mCTSIB ( p = .50)).

Conclusions

Improvements were similar for all patients receiving post-concussive physical therapy, regardless of time between injury and treatment onset, and regardless of time spent in treatment. These results may have implications for clinical decision-making and for third party payors’ coverage of post-concussion treatment. Longer periods of treatment may not necessarily be of greater benefit and application of treatment if delayed may also be beneficial. Limitations to the study, such as its retrospective nature, lack of randomization, and convenience sample size are discussed.

18 Manipulation Under Anaesthetic for Frozen Shoulder: Does Post-Operative Supervised Physiotherapy Affect the Outcome?

Introduction

This study compares two pathways for patients undergoing MUA for FS, one where physiotherapy advice is only given to the patient (Group 1), and the other where supervised hydrotherapy and physiotherapy occur post operatively (Group 2).

Method

A descriptive analysis of pre- and post-operative Oxford Shoulder Scores and change scores were performed.

Analysis of covariance (ANCOVA) was used to measure the effect of physiotherapy on post-operative OSS, with pre-operative OSS as the only covariate.

Results

The results for post-operative OSS were significantly greater for Group 2 than for Group 1 (40.7 for NHS and 44.7 for private, improvement of 17.32 for NHS and 18.23 for Private). The estimated effect of physiotherapy on postoperative OSS was an increase of 3.2 (95% confidence interval 1.5 – 4.8).

Conclusions

We detected a statistically significant increase in post-operative OSS in patients treated for frozen shoulder with MUA + physiotherapy compared with patients receiving MUA plus advice alone. These results suggest that physiotherapy does confer a real benefit, however the increased OSS is below the clinically significant level. Therefore, in a resource poor environment, such as may exist after COVID in many health care systems, MUA plus physio advice alone gives an excellent outcome for the treatment of FS.

Patient, Caregiver, and Provider Perspectives on Challenges and Solutions to Individualization of Care in Hemodialysis: A Qualitative Study

Background:

Clinical settings often make it challenging for patients with kidney failure to receive individualized hemodialysis (HD) care. Individualization refers to care that reflects an individual’s specific circumstances, values, and preferences.

Objective:

This study aimed to describe patient, caregiver, and health care professional perspectives regarding challenges and solutions to individualization of care in people receiving in-center HD.

Design:

In this multicentre qualitative study, we conducted focus groups with individuals receiving in-center HD and their caregivers and semi-structured interviews with health care providers from May 2017 to August 2018.

Setting:

Hemodialysis programs in 5 cities: Calgary, Edmonton, Winnipeg, Ottawa, and Halifax.

Participants:

Individuals receiving in-center HD for more than 6 months, aged 18 years or older, and able to communicate in English were eligible to participate, as well as their caregivers. Health care providers with HD experience were recruited using a purposive approach and snowball sampling.

Methods:

Two sequential methods of qualitative data collection were undertaken: (1) focus groups and interviews with HD patients and caregivers, which informed (2) individual interviews with health care providers. A qualitative descriptive methodology guided focus groups and interviews. Data from all focus groups and interviews were analyzed using conventional content analysis.

Results:

Among 82 patients/caregivers and 31 health care providers, we identified 4 main themes: session set-up, transportation and parking, socioeconomic and emotional well-being, and HD treatment location and scheduling. Particular challenges faced were as follows: (1) session set-up: lack of preferred supplies, machine and HD access set-up, call buttons, bed/chair discomfort, needling options, privacy in the unit, and self-care; (2) transportation and parking: lack of reliable/punctual service, and high costs; (3) socioeconomic and emotional well-being: employment aid, finances, nutrition, lack of support programs, and individualization of treatment goals; and (4) HD treatment location and scheduling: patient displacement from their usual spot, short notice of changes to dialysis time and location, lack of flexibility, and shortages of HD spots.

Limitations:

Uncertain applicability to non-English speaking individuals, those receiving HD outside large urban centers, and those residing outside of Canada.

Conclusions:

Participants identified challenges to individualization of in-center HD care, primarily regarding patient comfort and safety during HD sessions, affordable and reliable transportation to and from HD sessions, increased financial burden as a result of changes in functional and employment status with HD, individualization of treatment goals, and flexibility in treatment schedule and self-care. These findings will inform future studies aimed at improving patient-centered HD care.

Microfluidic Synthesis of Iron Oxide Nanoparticles

Research efforts into the production and application of iron oxide nanoparticles (IONPs) in recent decades have shown IONPs to be promising for a range of biomedical applications. Many synthesis techniques have been developed to produce high-quality IONPs that are safe for in vivo environments while also being able to perform useful biological functions. Among them, coprecipitation is the most commonly used method but has several limitations such as polydisperse IONPs, long synthesis times, and batch-to-batch variations. Recent efforts at addressing these limitations have led to the development of microfluidic devices that can make IONPs of much-improved quality. Here, we review recent advances in the development of microfluidic devices for the synthesis of IONPs by coprecipitation. We discuss the main architectures used in microfluidic device design and highlight the most prominent manufacturing methods and materials used to construct these microfluidic devices. Finally, we discuss the benefits that microfluidics can offer to the coprecipitation synthesis process including the ability to better control various synthesis parameters and produce IONPs with high production rates.

A Mixed Method Investigation to Determine Priorities for Improving Information, Interaction, and Individualization of Care Among Individuals on In-center Hemodialysis: The Triple I Study

BACKGROUND

Current health systems do not effectively address all aspects of chronic care. For better self-management of disease, kidney patients have identified the need for improved health care information, interaction with health care providers, and individualization of care.

OBJECTIVE

The Triple I study examined challenges to exchange of information, interaction between patients and health care providers and individualization of care in in-center hemodialysis with the aim of identifying the top 10 challenges that individuals on in-center hemodialysis face in these 3 areas.

DESIGN

We employed a sequential mixed methods approach with 3 phases:1. A qualitative study with focus groups and interviews (Apr 2017 to Aug 2018);2. A cross-sectional national ranking survey (Jan 2019 to May 2019);3. A prioritization workshop using a modified James Lind Alliance process (June 2019).

SETTING

In-center hemodialysis units in 7 academic centers across Canada: Vancouver, Calgary, Edmonton, Winnipeg, Ottawa, Montreal, and Halifax.

PARTICIPANTS

Individuals receiving in-center hemodialysis, their caregivers, and health care providers working in in-center hemodialysis participated in each of the 3 phases.

METHODS

In Phase 1, we collected qualitative data through (1) focus groups and interviews with hemodialysis patients and their caregivers and (2) individual interviews with health care providers and decision makers. Participants identified challenges to in-center hemodialysis care and potential solutions to these challenges. In Phase 2, we administered a pan-Canadian cross-sectional ranking survey. The survey asked respondents to prioritize the challenges to in-center hemodialysis care identified in Phase 1 by ranking their top 5 topics/challenges in each of the 3 "I" categories. In Phase 3, we undertook a face-to-face priority setting workshop which followed a modified version of the James Lind Alliance priority setting workshop process. The workshop employed an iterative process incorporating small and large group sessions during which participants identified, ranked, and voted on the top challenges and innovations to hemodialysis care. Four patient partners contributed to study design, implementation, analysis, and interpretation.

RESULTS

Across the 5 participating centers, we conducted 8 focus groups and 44 interviews, in which 113 participants identified 45 distinct challenges to in-center hemodialysis care. Subsequently, completion of a national ranking survey (n = 323) of these challenges resulted in a short-list of the top 30 challenges. Finally, using small and large group sessions to develop consensus during the prioritizing workshop, 38 stakeholders used this short-list to identify the top 10 challenges to in-center hemodialysis care. These included individualization of dialysis-related education; improved information in specific topic areas (transplant status, dialysis modalities, dialysis-related complications, and other health risks); more flexibility in hemodialysis scheduling; better communication and continuity of care within the health care team; and increased availability of transportation, financial, and social support programs.

LIMITATIONS

Participants were from urban centers and were predominately English-speaking. Survey response rate of 31.5% in Phase 2 may have led to selection bias. We collected limited information on social determinants of health, which could confound our results.

CONCLUSION

Overall, the challenges we identified demonstrate that individualized care and information that improves interaction with health care providers is important to patients receiving in-center hemodialysis. In future stages of this project, we will aim to address these challenges by trialing innovative patient-centered solutions.

TRIAL REGISTRATION

Not applicable.

Predicting Acute Kidney Injury after Surgery

Acute Kidney Injury (AKI) is a common complication after surgery. Recognition of patients at risk of AKI at an earlier stage is a priority for researchers and health care providers. The objective of this study is to develop machine learning prediction models of acute kidney injury (AKI) in patients who undergo surgery. The dataset used in this study consists of in-hospital patients' data of five different cohorts coming from different major procedure types. This data was collected from the SunRiseClinical Manager (SCM) electronic medical records system that is used in the Calgary Zone, Alberta, Canada from 2008 to 2015 where the patients are >=18 years of age. Five classifiers were experimented with: support vector machine, random forest, logistic regression, k-nearest neighbors, and adaptive boosting. The area under the receiver operating characteristics curve (AUROC) ranged between 0.62-0.84 and sensitivity and specificity ranged between 0.81-0.83 and 0.43-0.85, respectively. Predictions from these models can facilitate early intervention in AKI treatment.

Perioperative management for people with chronic kidney disease receiving dialysis undergoing major surgery: a protocol for a scoping review

INTRODUCTION

People with chronic kidney disease receiving dialysis (CKD G5D) have an increased risk of poor postoperative outcomes and a high incidence of major surgery. Despite the high burden of these combined risks, there is a paucity of evidence to support tailored perioperative strategies to manage this population. A comprehensive evidence synthesis would inform the management of these patients in the perioperative period and identify knowledge gaps. We describe a protocol for a scoping review of the literature to identify existing perioperative strategies, protocols, pathways and interventions for people with CKD G5D undergoing major surgery.

METHODS AND ANALYSIS

We will conduct a scoping review in accordance with the Joanna Briggs Institute methodology and report per the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for scoping reviews. In February 2020, we will complete our search of MEDLINE, EMBASE, CINAHL Plus, Cochrane Database of Systematic Reviews, and Cochrane Controlled Trials Registry for published literature from inception to present. All study types are eligible for inclusion, without language restriction. Studies reporting a perioperative intervention in adult patients with CKD G5D are eligible for inclusion. Studies in prevalent kidney transplant patients or patients with acute kidney injury, and studies that report on surgical approaches without consideration of perioperative management strategies, will be excluded. Reviewers will independently assess abstracts for all identified studies in duplicate, and again at the full-text stage. Following published literature searches, a search of the grey literature will be developed. We will extract and narratively report study, participant and intervention details. This will include a summary table outlining the strategies employed, organised into post hoc developed perioperative domains.

ETHICS AND DISSEMINATION

Ethical considerations do not apply to this scoping review. Findings will be disseminated through relevant conference presentations and publications.

Sex differences in the vascular access of hemodialysis patients: a cohort study

Background

We describe differences for probability of receiving a fistula attempt, achieving fistula use, remaining catheter-free and the rate of access-related procedures as a function of sex.

Methods

Prospectively collected vascular access data on incident dialysis patients from five Canadian programs using the Dialysis Measurement Analysis and Reporting System to determine differences in fistula-related outcomes between women and men. The probability of receiving a fistula attempt and the probability of fistula use were determined using binary logistic regression. Catheter and fistula procedure rates were described using Poisson regression. We studied time to fistula attempt and time to fistula use, accounting for competing risks.

Results

We included 1446 (61%) men and 929 (39%) women. Men had a lower body mass index (P < 0.001) and were more likely to have coronary artery disease (P < 0.001) and peripheral vascular disease (p < 0.001). A total of 688 (48%) men and 403 (43%) women received a fistula attempt. Women were less likely to receive a fistula attempt by 6 months {odds ratio [OR] 0.64 [95% confidence interval (CI) 0.52-0.79]} and to achieve catheter-free use of their fistula by 1 year [OR 0.38 (95% CI 0.27-0.53)]. At an average of 2.30 access procedures per person-year, there is no difference between women and men [incidence rate ratio (IRR) 0.97 (95% CI 0.87-1.07)]. Restricting to those with a fistula attempt, women received more procedures [IRR 1.16 (95% CI 1.04-1.30)] attributed to increased catheter procedures [IRR 1.50 (95% CI 1.27-1.78)]. There was no difference in fistula procedures [IRR women versus men 0.96 (95% CI 0.85-1.07)].

Conclusion

Compared with men, fewer women undergo a fistula attempt. This disparity increases after adjusting for comorbidities. Women have the same number of fistula procedures as men but are less likely to successfully use their fistula.

P0560POST-DISCHARGE FOLLOW UP AFTER AKI. AN EXTERNAL VALIDATION AND DECISION CURVE ANALYSIS OF TWO RISK MODELS

Background and Aims

There is limited evidence to inform which people should receive follow up after AKI and for what reasons. Here we report the external validation (geographical and temporal) and potential clinical utility of two complementary models for predicting different post-discharge outcomes after AKI. We used decision curve analysis, a technique that enables visualisation of the trade-off (net benefit) between identifying true positives and avoiding false positives across a range of potential risk thresholds for a risk model. Based on decision curve analysis we compared model guided approaches to follow up after AKI with alternative strategies of standardised follow up – e.g. follow up of all people with AKI, severe AKI, or a discharge eGFR&lt;30.

Method

The Alberta AKI risk model predicts the risk of stage G4 CKD at one year after AKI among those with a baseline GFR&gt;=45 and at least 90 days survival (2004-2014, n=9973). A trial is now underway using this tool at a 10% threshold to identify high risk people who may benefit from specialist nephrology follow up. The Aberdeen AKI risk model provides complementary predictions of early mortality or unplanned readmissions within 90 days of discharge (2003, n=16453), aimed at supporting non-specialists in discharge planning, with a threshold of 20-40% considered clinically appropriate in the study. For the Alberta model we externally validated using Grampian residents with hospital AKI in 2011-2013 (n=9382). For the Aberdeen model we externally validated using all people admitted to hospital in Grampian in 2012 (n=26575). Analysis code was shared between the sites to maximise reproducibility.

Results

Both models discriminated well in the external validation cohorts (AUC 0.855 for CKD G4, and AUC 0.774 for death and readmissions model), but as both models overpredicted risks, recalibration was performed. For both models, decision curve analysis showed that prioritisation of patients based on the presence or severity of AKI would be inferior to a model guided approach. For predicting CKD G4 progression at one year, a strategy guided by discharge eGFR&lt;30 was similar to a model guided approach at the prespecified 10% threshold (figure 1). In contrast for early unplanned admissions and mortality, model guided approaches were superior at the prespecified 20-40% threshold (figure 2).

Conclusion

In conclusion, prioritising AKI follow up is complex and standardised recommendations for all people may be an inefficient and inadequate way of guiding clinical follow-up. Guidelines for AKI follow up should consider suggesting an individualised approach both with respect to purpose and prioritisation.

An effective digital tourniquet utilising a fenestrated limb tourniquet

We describe a safe and effective digital tourniquet utilising a fenestrated limb tourniquet which would normally be used for venepuncture.

Patients, clinicians and researchers working together to improve cardiovascular health: a qualitative study of barriers and priorities for patient-oriented research

OBJECTIVES

The overall goal of this study is to identify priorities for cardiovascular (CV) health research that are important to patients and clinician-researchers. We brought together a group of CV patients and clinician-researchers new to patient-oriented research (POR), to build a multidisciplinary POR team and form an advisory committee for the Libin Cardiovascular Institute of Alberta.

DESIGN

This qualitative POR used a participatory health research paradigm to work with participants in eliciting their priorities. Therefore, participants were involved in priority setting, and analysis of findings. Participants also developed a plan for continued engagement to support POR in CV health research.

SETTING

Libin Cardiovascular Institute of Alberta, Cumming School of Medicine, University of Calgary, Canada.

PARTICIPANTS

A total of 23 participants, including patients and family caregivers (n=12) and clinician-researchers (n=11).

RESULTS

Participants identified barriers and facilitators to POR in CV health (lack of awareness of POR and poor understanding on the role of patients) and 10 research priorities for improving CV health. The CV health research priorities include: (1) CV disease prediction and prevention, (2) access to CV care, (3) communication with providers, (4) use of eHealth technology, (5) patient experiences in healthcare, (6) patient engagement, (7) transitions and continuity of CV care, (8) integrated CV care, (9) development of structures for patient-to-patient support and (10) research on rare heart diseases.

CONCLUSIONS

In this study, research priorities were identified by patients and clinician-researchers working together to improve CV health. Future research programme and projects will be developed to address these priorities. A key output of this study is the creation of the patient advisory council that will provide support and will work with clinician-researchers to improve CV health.