bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

BackgroundIn 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.MethodsA 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.ResultsTwenty-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.ConclusionComprehensive 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

IntroductionChest 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.MethodsWe 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.ResultIn 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.ConclusionEMS 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

BackgroundThe 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.MethodA 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.ResultsThe 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).DiscussionVolunteer 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

BackgroundParamedics 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.MethodData 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.ResultsA 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.ConclusionsEarly 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

BackgroundParamedics 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.MethodData 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.ResultsMajor 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.ConclusionsEarly 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

ObjectiveIntrahepatic 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.MethodsBlood 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.ResultsSystemic 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.ConclusionsiCCA 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

BackgroundMachine 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).MethodsData 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).ResultsWe 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.ConclusionThe 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

BackgroundDespite 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.MethodsWe 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.ResultsAmong 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).ConclusionsAmong 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.
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

BackgroundDue 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.MethodsWe 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.ResultsTests 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.ConclusionRising 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.
Mechanism of acitretin-induced relaxations in isolated rat thoracic aorta preparations
Authors: Efe Oğuzhan Ekin , Aydos Tolga Reşat , Emre Aydingoz Selda 
Published: August 2021

Acitretin is a member of vitamin A-derived retinoids, and its effect on vascular smooth muscle had not yet been studied. The aim of this study is to investigate the effect of acitretin, a retinoid, on vascular smooth muscle contractility. Thoracic aorta preparations obtained from 34 male Sprague–Dawley rats (355 ± 15 g) were studied in isolated organ baths containing Krebs–Henseleit solution. The relaxation responses were obtained with acitretin (10–12–10–4 M) in endothelium-preserved and endothelium-denuded aorta preparations precontracted with submaximal concentration of phenylephrine (10–6 M). The role of retinoic acid receptors (RARs), nitric oxide, adenylyl, and guanylyl cyclase enzymes, and potassium channels in these relaxation responses were investigated. Acitretin produced concentration-dependent relaxations, which were independent of its solvent dimethylsulfoxide (DMSO), in endothelium-denuded phenylephrine-precontracted thoracic aorta preparations. While incubation with the RAR antagonist (AGN193109, 10–5 M) had no effect on these relaxations; nitric oxide synthase inhibitor (L-NG-Nitro arginine methyl ester (L-NAME), 10–4 M), adenylyl cyclase inhibitor (SQ2253, 10–5 M), guanylyl cyclase inhibitor (oxadiazolo [4,3-a] quinoxalin-1-one (ODQ), 10–6 M), and potassium channel blocker (tetraethylammonium (TEA), 10–2 M) significantly eliminated the relaxation responses induced by acitretin. Acitretin induces relaxation in rat isolated thoracic aorta preparations without endothelium, which may be mediated by nitric oxide, cyclic adenosine monophosphate, and cyclic guanosine monophosphate-dependent kinases and potassium channels.
Enumeration of n-hypergroups on sets with two elements
Authors: Safari M. B. , Davvaz B. 
Published: August 2021

This paper is a continuation of ideas presented in [M. B. Safari, B. Davvaz and V. Leoreanu-Fotea, Enumeration of 3- and 4-hypergroups on sets with two elements, Eur. J. Combin. 44 (2015) 298–306]. We find the number and structure of non-isomorphism [Formula: see text]-hypergroups on sets with two elements. Moreover, we present a general template for some special cases of [Formula: see text]-hypergroups by linking the last results on [Formula: see text]-hypergroups.