bluuebunny/crossref_metadata_2025 huggingface dataset:
Spectral Stability Conditions for an Explicit Three-Level Finite-Difference Scheme for a Multidimensional Transport Equation with Perturbations
Authors: Zlotnik A. A. , Chetverushkin B. N.
Published: August 2021

We study difference schemes associated with a simplified linearized multidimensional hyperbolic quasi-gasdynamic system of differential equations. It is shown that an explicit two-level vector difference scheme with flux relaxation for a second-order hyperbolic equation with variable coefficients that is a perturbation of the transport equation with a parameter multiplying the highest derivatives can be reduced to an explicit three-level difference scheme. In the case of constant coefficients, the spectral condition for the time-uniform stability of this explicit three-level difference scheme is analyzed, and both sufficient and necessary conditions for this condition to hold are derived, in particular, in the form of Courant type conditions on the ratio of temporal and spatial steps.
Compact Difference Schemes on a Three-Point Stencil for Second-Order Hyperbolic Equations
Authors: Matus P. P. , Hoang Thi Kieu Anh
Published: August 2021

We consider compact difference schemes of approximation order $$4+2
$$ on a three-point spatial stencil for the
Klein–Gordon equations with constant and variable coefficients. New compact schemes are
proposed for one type of second-order quasilinear hyperbolic equations. In the case of constant
coefficients, we prove the strong stability of the difference solution under small perturbations of
the initial conditions, the right-hand side, and the coefficients of the equation. A priori estimates
are obtained for the stability and convergence of the difference solution in strong mesh norms.
Video-based reflection on neonatal interventions during COVID-19 using eye-tracking glasses: an observational study
Authors: Wagner Michael , den Boer Maria C , Jansen Sophie , Groepel Peter , Visser Remco , Witlox Ruben S G M , Bekker Vincent , Lopriore Enrico , Berger Angelika , te Pas Arjan B
Published: August 2021

Objective

The aim of this study was to determine the experience with, and the feasibility of, point-of-view video recordings using eye-tracking glasses for training and reviewing neonatal interventions during the COVID-19 pandemic.

Design

Observational prospective single-centre study.

Setting

Neonatal intensive care unit at the Leiden University Medical Center.

Participants

All local neonatal healthcare providers.

Intervention

There were two groups of participants: proceduralists, who wore eye-tracking glasses during procedures, and observers who later watched the procedures as part of a video-based reflection.

Main outcome measures

The primary outcome was the feasibility of, and the proceduralists and observers’ experience with, the point-of-view eye-tracking videos as an additional tool for bedside teaching and video-based reflection.

Results

We conducted 12 point-of-view recordings on 10 different patients (median gestational age of 30.9±3.5 weeks and weight of 1764 g) undergoing neonatal intubation (n=5), minimally invasive surfactant therapy (n=5) and umbilical line insertion (n=2). We conducted nine video-based observations with a total of 88 observers. The use of point-of-view recordings was perceived as feasible. Observers further reported the point-of-view recordings to be an educational benefit for them and a potentially instructional tool during COVID-19.

Conclusion

We proved the practicability of eye-tracking glasses for point-of-view recordings of neonatal procedures and videos for observation, educational sessions and logistics considerations, especially with the COVID-19 pandemic distancing measures reducing bedside teaching opportunities.
Observational cohort study of changing trends in non-invasive ventilation in very preterm infants and associations with clinical outcomes
Authors: Sand Laura , Szatkowski Lisa , Kwok T'ng Chang , Sharkey Don , Todd David A , Budge Helen , Ojha Shalini
Published: August 2021

Objective

To determine the change in non-invasive ventilation (NIV) use over time in infants born at <32 weeks’ gestation and the associated clinical outcomes.

Study design

Retrospective cohort study using routinely recorded data from the National Neonatal Research Database of infants born at <32 weeks admitted to neonatal units in England and Wales from 2010 to 2017.

Results

In 56 537 infants, NIV use increased significantly between 2010 and 2017 (continuous positive airway pressure (CPAP) from 68.5% to 80.2% in 2017 and high flow nasal cannula (HFNC) from 14% to 68%, respectively) (p<0.001)). Use of NIV as the initial mode of respiratory support also increased (CPAP, 21.5%–28.0%; HFNC, 1%–7% (p<0.001)).

HFNC was used earlier, and for longer, in those who received CPAP or mechanical ventilation. HFNC use was associated with decreased odds of death before discharge (adjusted OR (aOR) 0.19, 95% CI 0.17 to 0.22). Infants receiving CPAP but no HFNC died at an earlier median chronological age: CPAP group, 22 (IQR 10–39) days; HFNC group 40 (20–76) days (p<0.001). Among survivors, HFNC use was associated with increased odds of bronchopulmonary dysplasia (BPD) (aOR 2.98, 95% CI 2.81 to 3.15) and other adverse outcomes.

Conclusions

NIV use is increasing, particularly as initial respiratory support. HFNC use has increased significantly with a sevenfold increase soon after birth which was associated with higher rates of BPD. As more infants survive with BPD, we need robust clinical evidence, to improve outcomes with the use of NIV as initial and ongoing respiratory support.
Bullous fixed drug eruption following administration of the recombinant adjuvant Shingrix vaccine
Authors: Thompson Hallie , Nichols Laura , Gonzalez Santiago Tania
Published: August 2021

A 51-year-old woman with Crohn’s disease presented with a bullous rash on her left arm and axilla 2 days after receiving her second dose of the recombinant adjuvant Shingrix vaccine. PCR for herpes simplex virus (HSV) 1, HSV 2 and varicella zoster virus was negative. Punch biopsy revealed changes that were consistent with a bullous fixed drug eruption. She was successfully treated oral prednisone and topical triamcinolone cream. This is the first known case of a bullous fixed drug eruption due to the recombinant adjuvant Shingrix vaccine.
Low bone mineral density on DXA and slipped capital femoral epiphysis as rare presentation in a child with Rubinstein-Taybi syndrome
Authors: Karguppikar Madhura Bharat , Shah Nikhil , Khadilkar Vaman , Khadilkar Anuradha
Published: August 2021

We present a 7-year-old girl with Rubinstein-Taybi syndrome (RTS) and slipped capital femoral epiphysis (SCFE). She underwent bilateral arthroscopy with implant fixation for the SCFE and the symptoms resolved. This was followed by fracture of the femur after minor trauma. Dual energy X-ray absorptiometry (DXA) scan done to evaluate her bone health revealed a low bone mineral density (BMD). Our case highlights the finding of low BMD on DXA and rare association of SCFE in a child with RTS. The conundrum in this case is whether this child can be labelled to have osteoporosis as defined by the criteria given by the International Society for Clinical Densitometry guidelines.
Clinical efficacy with dabrafenib and trametinib in a T599_V600insT poorly differentiated metastatic thyroid carcinoma
Authors: Lee Chung-Shien , Miao Emily , Das Kasturi , Seetharamu Nagashree
Published: August 2021

BRAF (v-raf murine sarcoma viral oncogene homolog B1) and MEK (mitogen-activated protein kinase kinase) inhibitors have been shown to improve clinical outcomes in tumours presenting with mutations in theBRAFgene. The most common form of BRAF mutation is V600E/K and has been shown to occur in thyroid cancers. Treatment data for patients harbouring less frequent BRAF mutations are limited. In vitro studies have shown that mutations in codons 599–601 increase kinase activity similar to that in V600E mutations, which suggests that BRAF and MEK inhibitors could be an effective treatment option. Here, we report a case of a patient with thyroid carcinoma harbouring a rare amino acid insertion in codon 599 of theBRAFgene (T599_V600insT) treated with a BRAF and MEK inhibitor.
Colonic interposition for oesophageal replacement surgery in a patient with left broncho-oesophageal fistula: anaesthetic management
Authors: Girish Kavitha , Pappu Ameya , Ramachandran Rashmi , Rewari Vimi
Published: August 2021

Management of an uncorrected broncho-oesophageal fistula in the perioperative period is a challenge for the anaesthesiologist. Positive pressure ventilation which is inevitable during surgery will lead to gastric insufflation and there is a high risk of aspiration of gastric contents. In this case report, we discuss how we used a double lumen tube to occlude a pericarinal broncho-oesophageal fistula. This method was quite effective as it obviated the need for isolating the lung as well as ensured smooth delivery of positive pressure ventilation during the surgery.
Youth ice hockey COVID-19 protocols and prevention of sport-related transmission
Authors: Krug Allison , Appleby Richard , Pizzini Robert , Høeg Tracy Beth
Published: August 2021

Objectives

This observational study evaluated the impact of return-to-play protocols to prevent transmission of SARS-CoV-2 in a youth ice hockey programme in Virginia Beach, Virginia.

Methods

Following an outbreak of SARS-CoV-2 in November 2020, a COVID-19 Response Team evaluated the epidemiological data to identify transmission dynamics and develop enhanced protocols to prevent transmission. During the subsequent 18-week study period, incident cases were investigated to identify the likely transmission source; testing, quarantine and isolation recommendations were provided to families in accordance with Centers for Disease Control and Prevention guidelines.

Results

Simple but stringent protocols were implemented among 148 youth ice hockey players ages 6–18. Players were required to arrive at the rink in full gear; locker rooms were closed, building entry was limited to one parent per player, and masks were required at all times except for players on the ice. Following implementation of the enhanced protocols, more than 500 practices and games were completed with at least 15 858 athlete-hours of exposure and no within-programme COVID-19 transmission was detected despite high community incidence and sporadic household exposures.

Conclusion

This study suggests indoor youth sports can operate safely with appropriate protocols in place, even within communities of high COVID-19 transmission, even when athletes are not yet vaccinated or wearing masks during play. Transmission appears to be more likely in congested indoor areas involving adults than on the ice during play. Protocols should be developed in collaboration with programme participants. Strong collaboration in the interest of youth sports can motivate adoption of protocols which prevent within-team transmission.
Identifying patients with cerebral infarction within the time window compatible with reperfusion therapy, diagnostic performance of glutathione S-transferase-π (GST-π) and peroxiredoxin 1 (PRDX1): exploratory prospective multicentre study FLAG-1 protocol
Authors: Karakus Arif , Girerd Nicolas , Sanchez Jean-Charles , Sabben Candice , Wietrich Anthony , Lavandier Karine , Marchal Sophie , Aubertin Anne , Humbertjean Lisa , Mione Gioia , Bouali Sanae , Duarte Kevin , Reymond Sandrine , Gory Benjamin , Richard Sébastien
Published: August 2021

Introduction

Plasma biomarkers may be useful in diagnosing acute cerebral infarction requiring urgent reperfusion, but their performance remains to be confirmed. If confirmed, these molecules could be used to develop rapid and reliable decentralised measurement methods, making it possible to initiate reperfusion therapy before hospital admission. The FLAG-1 large prospective study will constitute a plasma bank to assess the diagnostic performance of two biomarkers: glutathione S-transferase-π and peroxiredoxin 1. These molecules are involved in the oxidative stress response and could identify cerebral infarction within a therapeutic window of less than 4.5 hours following the onset of symptoms. Secondary objectives include assessing performance of these biomarkers within 3-hour and 6-hour windows; identifying additional biomarkers diagnosing cerebral infarction and significant criteria guiding therapeutic decisions: ischaemic features of stroke, presence of diffusion/fluid-attenuated inversion recovery mismatch, volume of cerebral infarction and penumbra on cerebral MRI.

Methods and analysis

The exploratory, prospective, multicentre FLAG-1 Study will include 945 patients with acute stroke symptoms (onset ≤12 hours, National Institute of Health Stroke Scale score ≥3). Each patient’s 25 mL blood sample will be associated with cerebral MRI data. Two patient groups will be defined based on the time of blood collection (before and after 4.5 hours following onset). Receiver operating characteristic analysis will determine the diagnostic performance of each biomarker, alone or in combination, for the identification of cerebral infarction <4.5 hours.

Ethics and dissemination

The protocol has been approved by an independent ethics committee. Biological samples are retained in line with best practices and procedures, in accordance with French legislation. Anonymised data and cerebral imaging records are stored using electronic case report forms and a secure server, respectively, registered with the French Data Protection Authority (Commission Nationale de l"Informatique et des Libertés (CNIL)). Results will be disseminated through scientific meetings and publication in peer-reviewed medical journals.

Trial registration number

ClinicalTrials.gov Registry (NCT03364296).
Internet-based cognitive–behavioural therapy for tinnitus: secondary analysis to examine predictors of outcomes
Authors: Rodrigo Hansapani , Beukes Eldré W , Andersson Gerhard , Manchaiah Vinaya
Published: August 2021

Objectives

The current study examined predictors of outcomes of internet-based cognitive–behavioural therapy (ICBT) for individuals with tinnitus.

Design

Secondary analysis of intervention studies.

Setting

Internet-based guided tinnitus intervention provided in the UK.

Participants

228 individuals who underwent ICBT.

Interventions

ICBT.

Primary and secondary outcome measures

The key predictor variables included demographic, tinnitus, hearing-related and treatment-related variables as well as clinical factors (eg, anxiety, depression, insomnia), which can have an impact on the treatment outcome. A 13-point reduction in Tinnitus Functional Index (TFI) scores has been defined as a successful outcome.

Results

Of the 228 subjects who were included in the study, 65% had a successful ICBT outcome. As per the univariate analysis, participants with a master’s degree or above had the highest odds of having a larger reduction in tinnitus severity (OR 3.47; 95% CI 1.32 to 12.51), compared with the participants who had education only up to high school or less. Additionally, the baseline tinnitus severity was found to be a significant variable (OR 2.65; 95% CI 1.50 to 4.67) contributing to a successful outcome with the intervention. Both linear and logistic regression models have identified education level and baseline tinnitus severity to be significant predictor variables contributing to a reduction in tinnitus severity post-ICBT. As per the linear regression model, participants who had received disability allowance had shown a 25.3-point lower TFI reduction compared with those who did not experience a decrease in their workload due to tinnitus after adjusting for baseline tinnitus severity and their education level.

Conclusions

Predictors of intervention outcome can be used as a means of triaging patients to the most suited form of treatment to achieve optimal outcomes and to make healthcare savings. Future studies should consider including a heterogeneous group of participants as well as other predictor variables not included in the current study.

ClinicalTrial.gov Registration:NCT02370810(completed);NCT02665975(completed)
Early warning and rapid public health response to prevent COVID-19 outbreaks in long-term care facilities (LTCF) by monitoring SARS-CoV-2 RNA in LTCF site-specific sewage samples and assessment of antibodies response in this population: prospective study protocol
Authors: Lee Bonita E , Sikora Christopher , Faulder Douglas , Risling Eleanor , Little Lorie A , Qiu Yuanyuan , Gao Tiejun , Bulat Ross , Craik Stephen , Hrudey Steve E , Ohinmaa Arto , Estabrooks Carole A , Gingras Anne-Claude , Charlton Carmen , Kim John , Wood Heidi , Robinson Alyssia , Kanji Jamil N , Zelyas Nathan , O’Brien Sheila F , Drews Steven , Pang Xiao-Li
Published: August 2021

Introduction

The COVID-19 pandemic has an excessive impact on residents in long-term care facilities (LTCF), causing high morbidity and mortality. Early detection of presymptomatic and asymptomatic COVID-19 cases supports the timely implementation of effective outbreak control measures but repetitive screening of residents and staff incurs costs and discomfort. Administration of vaccines is key to controlling the pandemic but the robustness and longevity of the antibody response, correlation of neutralising antibodies with commercial antibody assays, and the efficacy of current vaccines for emerging COVID-19 variants require further study. We propose to monitor SARS-CoV-2 in site-specific sewage as an early warning system for COVID-19 in LTCF and to study the immune response of the staff and residents in LTCF to COVID-19 vaccines.

Methods and analysis

The study includes two parts: (1) detection and quantification of SARS-CoV-2 in LTCF site-specific sewage samples using a molecular assay followed by notification of Public Health within 24 hours as an early warning system for appropriate outbreak investigation and control measures and cost–benefit analyses of the system and (2) testing for SARS-CoV-2 antibodies among staff and residents in LTCF at various time points before and after COVID-19 vaccination using commercial assays and neutralising antibody testing performed at a reference laboratory.

Ethics and dissemination

Ethics approval was obtained from the University of Alberta Health Research Ethics Board with considerations to minimise risk and discomforts for the participants. Early recognition of a COVID-19 case in an LTCF might prevent further transmission in residents and staff. There was no direct benefit identified to the participants of the immunity study. Anticipated dissemination of information includes a summary report to the immunity study participants, sharing of study data with the scientific community through the Canadian COVID-19 Immunity Task Force, and prompt dissemination of study results in meeting abstracts and manuscripts in peer-reviewed journals.
Improving diagnostic performance through feedback: the Diagnosis Learning Cycle
Authors: Fernandez Branson Carolina , Williams Michelle , Chan Teresa M , Graber Mark L , Lane Kathleen P , Grieser Skip , Landis-Lewis Zach , Cooke James , Upadhyay Divvy K , Mondoux Shawn , Singh Hardeep , Zwaan Laura , Friedman Charles , Olson Andrew P J
Published: August 2021

Background

Errors in reasoning are a common cause of diagnostic error. However, it is difficult to improve performance partly because providers receive little feedback on diagnostic performance. Examining means of providing consistent feedback and enabling continuous improvement may provide novel insights for diagnostic performance.

Methods

We developed a model for improving diagnostic performance through feedback using a six-step qualitative research process, including a review of existing models from within and outside of medicine, a survey, semistructured interviews with individuals working in and outside of medicine, the development of the new model, an interdisciplinary consensus meeting, and a refinement of the model.

Results

We applied theory and knowledge from other fields to help us conceptualise learning and comparison and translate that knowledge into an applied diagnostic context. This helped us develop a model, the Diagnosis Learning Cycle, which illustrates the need for clinicians to be given feedback about both their confidence and reasoning in a diagnosis and to be able to seamlessly compare diagnostic hypotheses and outcomes. This information would be stored in a repository to allow accessibility. Such a process would standardise diagnostic feedback and help providers learn from their practice and improve diagnostic performance. This model adds to existing models in diagnosis by including a detailed picture of diagnostic reasoning and the elements required to improve outcomes and calibration.

Conclusion

A consistent, standard programme of feedback that includes representations of clinicians’ confidence and reasoning is a common element in non-medical fields that could be applied to medicine. Adapting this approach to diagnosis in healthcare is a promising next step. This information must be stored reliably and accessed consistently. The next steps include testing the Diagnosis Learning Cycle in clinical settings.
Anxiety and depression prevalence in digestive cancers: a systematic review and meta-analysis
Authors: Zamani Mohammad , Alizadeh-Tabari Shaghayegh
Published: August 2021

Background

Cancers of the digestive system can be associated with disturbing and disabling symptoms, which can contribute to a negative psychological pressure on patients.

Aim

To investigate the reported prevalence of symptoms of anxiety and depression in patients with major digestive cancers, including oesophageal, gastric, colorectal, pancreatic or hepatic cancers.

Methods

We searched Embase, PubMed, Scopus and Web of Science for articles published from inception to December 2020. We included studies reporting the prevalence of anxiety or depression symptoms using validated questionnaires in adult patients (≥18 years).

Results

In total, 51 eligible papers were finally included. Overall, the pooled prevalence of anxiety symptoms was 20.4% (95% CI 17% to 23.8%). The estimate in patients with gastrointestinal (GI) cancers was 19.1% and in patients with hepatic cancer was 29.1%. Among GI cancers, the highest pooled prevalence of anxiety symptoms related to oesophageal cancer (20.6%), while the lowest pooled prevalence pertained to gastric cancer (18.7%). Regarding depression symptoms, the overall pooled prevalence was 30.2% (95% CI 24.3% to 36.1%). The estimate in patients with GI cancers was 31% and in patients with hepatic cancer was 21.5%. Among GI cancers, the highest pooled prevalence of depression symptoms related to oesophageal cancer (45.2%), while the lowest pooled prevalence pertained to colorectal cancer (22.9%).

Conclusion

A considerable prevalence of anxiety and depression symptoms is observed in patients with digestive cancers. Screening and preventive measures with early management of these psychological problems by clinicians could possibly improve outcomes for these patients.

PROSPERO registration number

CRD42020210079.
PP18 Is there provider induced demand at emergency departments with primary care services? Patient, local and wider system factors described to influence demand for primary care in emergency departments: realist evaluation
Authors: Edwards Michelle , Cooper Alison , Stevens Andrew Carson , Edwards Adrian , Hughes Thomas , Snooks Helen , Anderson Pippa , Porter Alison , Evans Bridie , Dale Jeremy , Cooke Matthew , Hibbert Peter , Siriwardena Aloysius Niroshan
Published: August 2021

Background

Evidence from evaluations of emergency departments (EDs) with co-located primary care services suggests that they influence additional demand for non-urgent care (provider-induced demand). In a realist review of the literature on the effects of primary care services in EDs we proposed a theory that when primary care services are distinct at an ED they may encourage additional primary care demand and when primary care clinicians work indistinctly in the ED there is no additional demand. We aimed to explore evidence for this theory and explain contexts, mechanisms and outcomes that influence such demand.

Methods

We used realist evaluation methodology and carried out observations of key processes. We interviewed 23 patients, 21 ED clinical directors, 26 other ED staff members and 26 GPs at 13 EDs (England & Wales). Field notes and audio-recorded interviews were transcribed and analysed by creating context, mechanism and outcome configurations to refine and develop theories relating to provider induced demand.

Results

EDs with distinct primary care services were perceived to attract more demand for primary care than EDs where primary care clinicians worked indistinctly because the primary care service was visible, widely known about, enabled direct access, and received NHS 111 referrals. Other influences on demand were patients’ experiences of accessing primary care, the capacity for urgent care in the community, location of the ED and public transport links, service design and developments (new buildings, renovations) and population characteristics (unfamiliarity with local healthcare services, not registered with a GP or different cultural perceptions of seeking health care).

Conclusions

A range of patient, local-system and wider-system factors contribute to additional demand at an ED with co-located primary care services. Our findings can inform providers and policymakers in developing strategies to limit the effect of these influences on additional demand.
PP20 UK Ambulance Service resuscitation management of pulseless electrical activity: a systematic review of text and opinion
Authors: Coppola Ali , Smyth Michael A , Johnston Sasha , Black Sarah , Endacott Ruth
Published: August 2021

Background

In the United Kingdom, out of hospital cardiac arrest patients with pulseless electrical activity (PEA) have a poor survival to discharge rate of 5.3%.1 PEA is managed according to national guidelines.2 These guidelines are imperfect due to limited research resulting in ambulance services locally amending guidelines to support resuscitation decisions.3 This review aimed to examine the local guidelines of UK ambulance services for the management of PEA.

Methods

A three-step search strategy was applied from August 2020 to October 2020. 1) A search of UK ambulance service websites was conducted to identify published local guidelines. Where guidelines were not available a written request was made for the guideline, associated guideline or a narrative summary in the absence of a guideline. 2) Documents referenced within the local guidelines specific to pulseless electrical activity were identified and extracted as supporting literature. 3) Documents referenced in the supporting literature identified as having pulseless electrical activity in the title were extracted.

Results

Twenty-two documents of textual data met the inclusion criteria. Twenty-nine conclusions were extracted and analysed to generate ten categories, forming three synthesised themes relating to the variability in the clinical management of PEA between UK ambulance services, the early identification of reversible causes and appropriate treatment options to increase survivability and the consensus for further research.

Conclusion

Comprehensive national guidelines are lacking due to limited research. The local clinical guidelines and practices of UK ambulance services which aim to address the gaps in research, introduce variability in the management of pulseless electrical activity. Early identification and treatment to reverse the cause of pulseless electrical activity was highlighted to improve patient survival, however, this was complex and challenging to achieve during pre-hospital resuscitation. There was a consensus in the paucity of evidence and the potential for future prognostic research to improve patient outcomes.
PP23 Accuracy of emergency medical services (EMS) telephone triage in identifying acute coronary syndrome (ACS) for chest pain patients. A systematic review abstract
Authors: Alotaibi Ahmed , Alghamdi Abdulrhman , Reynard Charles , Body Richard
Published: August 2021

Introduction

Chest pain is one of the most common reasons for ambulance callouts and presentation to Emergency Departments (EDs). Differentiating patients with serious conditions (e.g. acute coronary syndrome [ACS]) from the majority, who have self-limiting, non-cardiac conditions is extremely challenging. This causes over-triage and over-use of healthcare resources. We aimed to systematically review existing evidence on the accuracy of emergency telephone triage to detect ACS or life-threatening conditions associated with chest pain.

Methods

We conducted a systematic review in accordance with PRISMA guidelines. Two independent investigators searched the Embase, Medline, and Cinahl databases for relevant papers. We included retrospective and prospective cohort studies written in English and investigating EMS telephone triage for chest pain patients linked with final diagnosis of ACS. Studies were summarised in a narrative format as the data were not suitable for meta-analysis.

Result

In total, 553 studies were identified from the literature search and cross-referencing. After excluding 550 studies, three were eligible for inclusion. Among those 3 studies, there are different prediction models developed by authors with variation in variables to detect ACS. The result showed that dispatch triage tools have good sensitivity to detect ACS and life-threatening conditions although they are used to triage sign and symptoms rather than diagnosing the patients. On the other hand, prediction models were built to detect ACS and life-threatening conditions and therefore it showed better sensitivity and NPV.

Conclusion

EMS dispatch systems accuracy for ACS and life-threatening conditions associated with chest pain is good. Since the dispatch tools were built to triage ambulance response priority based on sign and symptoms, this led to over triage among non-life-threatening chest pain patients. Over triage were slightly reduced by deriving prediction models and showed better sensitivity.
PP28 Volunteer emergency responder response to the COVID-19 pandemic surge
Authors: Aziz Shadman , Nijhawan Aditi , Palfreyman-Jones Samantha , Hartley-Sharpe Chris
Published: August 2021

Background

The London Ambulance Service (LAS) runs an Emergency Responder (ER) scheme, where trained volunteers respond to 999 calls in blue-light rapid response vehicles (RRVs), alongside the statutory ambulance service response.

The COVID-19 pandemic caused an unprecedented surge in call volume which, combined with reduced staffing of double-crewed ambulances (DCAs) due to illness, severely impaired the service’s ability to respond to calls.

In response to this, as well as increasing volunteer RRV shifts, ERs were given additional up-skill training to work with regular ambulance service clinicians on DCAs, thus increasing the number of DCAs available to attend calls.

This study aims to review the response to the COVID-19 pandemic provided by ERs.

Method

A retrospective review was conducted of all ER shifts on volunteer RRVs and the service’s front-line DCAs. Data from the same time period (March 1 – April 30) was compared between 2019 (pre-pandemic period) and 2020 (pandemic period). The statistical significance of proportions was calculated using the χ2test.

Results

The absolute number of RRV hours volunteered by ERs increased by 34.2% (2,017 to 2,707), resulting in a 21.2% increase in RRV shifts (227 to 275) during the pandemic period. Furthermore, the proportion of C1 (life-threatening) incidents attended by ER RRVs doubled (32.4% vs 61.1%, p < 0.0001). In addition to RRV shifts, ERs volunteered 1,222 hours on DCAs during the pandemic, resulting in 125 additional DCA resources available. The combined total hours provided by ERs (RRV/DCA) increased by 94.8% (2,017 to 3,929).

Discussion

Volunteer responders are a valuable resource during times of surge. In addition to volunteer RRV shifts, they have to the potential to assist ambulance service clinicians on DCAs. Future pandemic or winter-pressure plans should incorporate volunteer responders. This study predominantly looked at volunteer capacity, and further work is required to investigate patient-centred outcomes.
PP33 Lived experiences of paramedics across England during the COVID-19 outbreak; initial results. Poster Presentation
Authors: Cormack Stef , Boechler Lindsey , Ford-Jones Polly , Cameron Cheryl , Chris Smith J , Suthers Patrick
Published: August 2021

Background

Paramedics are experiencing numerous policy and guideline changes in addition to facing enhanced risk of personal exposure during the COVID-19 pandemic. The COVID-19 outbreak offers an opportunity to capture the experiences of paramedics during substantial and rapid changes to workplace policy, guidelines, and professional roles in the healthcare system. To date, this ongoing study has captured a better understanding of the lived experiences of English paramedics.

Method

Data were collected through an online survey, consisting of QUAN +QUAL questions. The study, theoretically grounded in a phenomenological approach, employed inductive thematic analysis to code the data. QUAN answers were analysed using descriptive statistics and chi-square to test for association between demographic data and answers.

Results

A total of 34 survey responses from September – December 2020 have been received from across England, with the survey remaining open. Major themes to date have identified both professional and personal elements. There is a feeling of increased pressure related to public expectation, with noted increases in call volumes in some areas. There has been a change to the workforce and increased levels of sickness. The type and level of PPE as well as employer communication varies depending on the area respondents work in. Many participants also expressed increased stress, exhaustion and anxiety negatively impacting their mental health.

Conclusions

Early results confirm a need for paramedics to adapt professional approaches to overcome barriers presented by COVID-19. There appears to be a disparity in the amount of communication, PPE and support depending on the area worked in. Respondents are fatigued and worried about others, including families. Yet, there remains a clear professional attitude and commitment to providing care throughout the pandemic. The survey remains open with a comparison of data between Canada and England planned.
PP36 Supporting paramedics on the frontlines amidst the COVID-19 pandemic: exploring impactful leadership approaches in Canada
Authors: Boechler Lindsey , Cormack Stefanie , Ford-Jones Polly , Cameron Cheryl , Chris Smith J , Suthers Patrick
Published: August 2021

Background

Paramedics are experiencing numerous policy and protocol changes in addition to facing enhanced risk of personal exposure during the COVID-19 pandemic. The COVID-19 outbreak offers an opportunity to capture the experiences of paramedics during substantial and rapid changes to workplace policy, protocols, and professional roles in the healthcare system. To date, this ongoing multi-jurisdictional study has captured a better understanding of the lived experiences of Canadian paramedics throughout the COVID-19 outbreak and provided insight to which leadership approaches have been most impactful throughout such unprecedented circumstances.

Method

Data was collected through an online survey, consisting of quantitative and qualitative questions. Survey responses (n=428) were received between April 2, 2020 and August 1, 2020. The study, theoretically grounded in a phenomenological approach, employed inductive thematic analysis to code the data. The survey remains open and has expanded to include England for further data collection as the pandemic continues to evolve.

Results

Major themes identified encompassed both professional and personal elements. Although some participants praised organizational leadership and how professional needs had been met throughout the first wave of the COVID-19 outbreak, other respondents expressed weariness to change management approaches and further need for clear communication strategies. Many participants also expressed increased stress, exhaustion and anxiety negatively impacting their mental health.

Conclusions

Early results confirmed a need for paramedics to adapt professional approaches to overcome barriers presented by COVID-19. Although most respondents noted confidence in their ability to provide patient care to those exhibiting symptoms, many noted concern regarding changes to standard of care for patients. In this presentation, we will discuss preliminary results from our study, and share recommendations pertaining to leadership and change management impacting paramedic practice.
GM-CSF drives myelopoiesis, recruitment and polarisation of tumour-associated macrophages in cholangiocarcinoma and systemic blockade facilitates antitumour immunity
Authors: Ruffolo Luis I , Jackson Katherine M , Kuhlers Peyton C , Dale Benjamin S , Figueroa Guilliani Nathania M , Ullman Nicholas A , Burchard Paul R , Qin Shuyang S , Juviler Peter G , Keilson Jessica Millian , Morrison Ashley B , Georger Mary , Jewell Rachel , Calvi Laura M , Nywening Timothy M , O'Dell Michael R , Hezel Aram F , De Las Casas Luis , Lesinski Gregory B , Yeh Jen Jen , Hernandez-Alejandro Roberto , Belt Brian A , Linehan David C
Published: August 2021

Objective

Intrahepatic cholangiocarcinoma (iCCA) is rising in incidence, and at present, there are limited effective systemic therapies. iCCA tumours are infiltrated by stromal cells, with high prevalence of suppressive myeloid populations including tumour-associated macrophages (TAMs) and myeloid-derived suppressor cells (MDSCs). Here, we show that tumour-derived granulocyte–macrophage colony-stimulating factor (GM-CSF) and the host bone marrow is central for monopoiesis and potentiation of TAMs, and abrogation of this signalling axis facilitates antitumour immunity in a novel model of iCCA.

Methods

Blood and tumours were analysed from iCCA patients and controls. Treatment and correlative studies were performed in mice with autochthonous and established orthotopic iCCA tumours treated with anti-GM-CSF monoclonal antibody.

Results

Systemic elevation in circulating myeloid cells correlates with poor prognosis in patients with iCCA, and patients who undergo resection have a worse overall survival if tumours are more infiltrated with CD68+TAMs. Mice with spontaneous iCCA demonstrate significant elevation of monocytic myeloid cells in the tumour microenvironment and immune compartments, and tumours overexpress GM-CSF. Blockade of GM-CSF with a monoclonal antibody decreased tumour growth and spread. Mice bearing orthotopic tumours treated with anti-GM-CSF demonstrate repolarisation of immunosuppressive TAMs and MDSCs, facilitating T cell response and tumour regression. GM-CSF blockade dampened inflammatory gene networks in tumours and TAMs. Human tumours with decreased GM-CSF expression exhibit improved overall survival after resection.

Conclusions

iCCA uses the GM-CSF-bone marrow axis to establish an immunosuppressive tumour microenvironment. Blockade of the GM-CSF axis promotes antitumour T cell immunity.
Diagnostic performance of an algorithm for automated large vessel occlusion detection on CT angiography
Authors: Luijten Sven P R , Wolff Lennard , Duvekot Martijne H C , van Doormaal Pieter-Jan , Moudrous Walid , Kerkhoff Henk , Lycklama a Nijeholt Geert J , Bokkers Reinoud P H , Yo Lonneke S F , Hofmeijer Jeannette , van Zwam Wim H , van Es Adriaan C G M , Dippel Diederik W J , Roozenbeek Bob , van der Lugt Aad
Published: August 2021

Background

Machine learning algorithms hold the potential to contribute to fast and accurate detection of large vessel occlusion (LVO) in patients with suspected acute ischemic stroke. We assessed the diagnostic performance of an automated LVO detection algorithm on CT angiography (CTA).

Methods

Data from the MR CLEAN Registry and PRESTO were used including patients with and without LVO. CTA data were analyzed by the algorithm for detection and localization of LVO (intracranial internal carotid artery (ICA)/ICA terminus (ICA-T), M1, or M2). Assessments done by expert neuroradiologists were used as reference. Diagnostic performance was assessed for detection of LVO and per occlusion location by means of sensitivity, specificity, and area under the curve (AUC).

Results

We analyzed CTAs of 1110 patients from the MR CLEAN Registry (median age (IQR) 71 years (60–80); 584 men; 1110 with LVO) and of 646 patients from PRESTO (median age (IQR) 73 years (62–82); 358 men; 141 with and 505 without LVO). For detection of LVO, the algorithm yielded a sensitivity of 89% in the MR CLEAN Registry and a sensitivity of 72%, specificity of 78%, and AUC of 0.75 in PRESTO. Sensitivity per occlusion location was 88% for ICA/ICA-T, 94% for M1, and 72% for M2 occlusion in the MR CLEAN Registry, and 80% for ICA/ICA-T, 95% for M1, and 49% for M2 occlusion in PRESTO.

Conclusion

The algorithm provided a high detection rate for proximal LVO, but performance varied significantly by occlusion location. Detection of M2 occlusion needs further improvement.
Influence of prior intravenous thrombolysis on outcome after failed mechanical thrombectomy: ETIS registry analysis
Authors: Rozes Claire , Maier Benjamin , Gory Benjamin , Bourcier Romain , Kyheng Maeva , Labreuche Julien , Consoli Arturo , Mazighi Mikael , Blanc Raphaël , Caroff Jildaz , Eugene Francois , Naggara Olivier , Gariel Florent , Sibon Igor , Lapergue Bertrand , Marnat Gaultier
Published: August 2021

Background

Despite constant improvements in recent years, sufficient reperfusion after mechanical thrombectomy (MT) is not reached in up to 15% of patients with large vessel occlusion stroke (LVOS). The outcome of patients with unsuccessful reperfusion after MT especially after intravenous thrombolysis (IVT) use is not known. We investigated the influence of initial IVT in this particular group of patients with failed intracranial recanalization.

Methods

We conducted a retrospective analysis of the Endovascular Treatment in Ischemic Stroke (ETIS) registry from January 2015 to December 2019. Patients presenting with LVOS of the anterior circulation and final modified Thrombolysis in Cerebral Infarction score (mTICI) of 0, 1 or 2a were included. Posterior circulation, isolated cervical carotid occlusions and successful reperfusions (mTICI 2b, 2c or 3) were excluded. The primary endpoint was favorable outcome (modified Rankin Scale score of 0–2) after 3 months. Secondary endpoints were safety outcomes including mortality, any intracranial hemorrhage (ICH), parenchymal hematoma (PH) and symptomatic intracranial hemorrhage (sICH) rates.

Results

Among 5076 patients with LVOS treated with MT, 524 patients with insufficient recanalization met inclusion criteria, of which 242 received IVT and 282 did not. Functional outcome was improved in the MT+IVT group compared with the MT alone group, although the difference did not reach statistical significance (23.0% vs 12.9%; adjusted OR=1.82; 95% CI 0.98 to 3.38; p=0.058). However, 3 month mRS shift analysis showed a significant benefit of IVT (adjusted OR=1.68; 95% CI 1.56 to 6.54). ICH and sICH rates were similar in both groups, although PH rate was higher in the MT+IVT group (adjusted OR=3.20; 95% CI 1.56 to 6.54).

Conclusions

Among patients with LVOS in the anterior circulation and unsuccessful MT, IVT was associated with improved functional outcome even after unsuccessful MT. Despite recent trials questioning the place of IVT in the LVOS reperfusion strategy, these findings emphasize a subgroup of patients still benefiting from IVT.
Huntington’s disease: diagnosis and management
Authors: Stoker Thomas B , Mason Sarah L , Greenland Julia C , Holden Simon T , Santini Helen , Barker Roger A
Published: August 2021

Huntington’s disease (HD) is an inherited neurodegenerative disease characterised by neuropsychiatric symptoms, a movement disorder (most commonly choreiform) and progressive cognitive impairment. The diagnosis is usually confirmed through identification of an increased CAG repeat length in the huntingtin gene in a patient with clinical features of the condition. Though diagnosis is usually straightforward, unusual presentations can occur, and it can be difficult to know when someone has transitioned from being an asymptomatic carrier into the disease state. This has become increasingly important recently, with several putative disease-modifying therapies entering trials. A growing number of conditions can mimic HD, including rare genetic causes, which must be considered in the event of a negative HD genetic test. Patients are best managed in specialist multidisciplinary clinics, including when considering genetic testing. Current treatments are symptomatic, and largely directed at the chorea and neurobehavioural problems, although supporting trial evidence for these is often limited.
Evidence of changing sexual behaviours and clinical attendance patterns, alongside increasing diagnoses of STIs in MSM and TPSM
Authors: MacGregor Louis , Speare Nathan , Nicholls Jane , Harryman Lindsey , Horwood Jeremy , Kesten Joanna May , Lorenc Ava , Horner Patrick , Edelman Natalie Lois , Muir Peter , North Paul , Gompels Mark , Turner Katy M E
Published: August 2021

Background

Due to rising numbers of STI diagnosis and increasing prevalence of antimicrobial resistance, we explored trends in STI testing frequency and diagnoses, alongside sexual decision making and attitudes concerning condom use and HIV pre-exposure prophylaxis (PrEP) at a large urban UK sexual health clinic.

Methods

We examined 66 528 electronic patient records covering 40 321 attendees between 2016 and 2019, 3977 of whom were men who have sex with men or trans persons who have sex with men (MSM/TPSM). We also explored responses from MSM/TPSM attendees sent an electronic questionnaire between November 2018 and 2019 (n=1975) examining behaviours/attitudes towards PrEP. We measured trends in STI diagnoses and sexual behaviours including condomless anal intercourse (CAI), using linear and logistic regression analyses.

Results

Tests resulting in gonorrhoea, chlamydia or syphilis diagnoses increased among MSM/TPSM from 13.5% to 18.5% between 2016 and 2019 (p<0.001). The average MSM/TPSM STI testing frequency increased from 1.5/person/year to 2.1/person/year (p=0.017). Gay MSM/TPSM had the highest proportions of attendances resulting in diagnoses, increasing from 15.1% to 19.6% between 2016 and 2019 (p<0.001) compared with bisexual/other MSM/TPSM increasing from 6.9% to 14.5% (p<0.001), alongside smaller but significant increases in non-MSM/TPSM from 5.9% to 7.7% (p<0.001).

The proportion of MSM/TPSM clinic attendees reporting CAI in the previous 3 months prior to at least one appointment in a given year increased significantly from 40.6% to 45.5% between 2016 and 2019 (p<0.0001) and average number of partners from 3.8 to 4.5 (p=0.002). Of 617 eligible questionnaire responses, 339/578 (58.7%) HIV-negative and 29/39 (74.4%) HIV-positive MSM/TPSM indicated they would be more likely to have CAI with someone on PrEP versus not on PrEP. 358/578 (61.9%) HIV-negative respondents said that PrEP use would make them more likely to have CAI with HIV-negative partners.

Conclusion

Rising numbers of STI diagnoses among MSM/TPSM are not attributable to increased testing alone. Increased CAI and number of partners may be attributable to evolving sexual decision making among PrEP users and their partners. Proportionally, bisexual/other MSM/TPSM have the steepest increase in STI diagnoses.