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In this paper we demonstrate on the basis of diachronic and synchronic data from a variety of languages that progressives are particularly liable to be used for the expression of extravagance. We define extravagant language use as a signaling mechanism that consists in the exploitation of an unconventional construction in a given context as a way for speakers to indicate that there is something non-canonical about the situation that they are reporting. Novel constructions naturally lend themselves to such extravagant exploitation, since they are by definition to a certain extent unconventional. This is why, as we will demonstrate, the English, Dutch and French progressives were notably often recruited in extravagant contexts at the onset of their development. However, our synchronic data reveal that Present-day English, Dutch and French progressives continue to be used for extravagant purposes, which suggests that there is something inherent about progressive aspect that makes it liable to such expressive usage. This is confirmed by data from other, typologically diverse languages. We offer a cognitive-semantic analysis in terms of epistemic contingency in order to account for this intrinsic association of progressive aspect and extravagance across languages. Our analysis thus reveals that extravagance is not a transient property of emerging progressives, but that, instead, the semantics of these constructions makes them particularly liable to be recruited for extravagant purposes. It also demonstrates that in order to analyze the range of uses of progressive constructions in a unified fashion, we need to look beyond the temporal import of these constructions.
The mechanisms underlying both depressive and anxiety disorders remain poorly understood. One of the reasons for this is the lack of a valid, evidence-based system to classify persons into specific subtypes based on their depressive and/or anxiety symptomatology. In order to do this without a priori assumptions, non-parametric statistical methods seem the optimal choice. Moreover, to define subtypes according to their symptom profiles and inter-relations between symptoms, network models may be very useful. This study aimed to evaluate the potential usefulness of this approach.
A large community sample from the Canadian general population (N = 254 443) was divided into data-driven clusters using non-parametric k-means clustering. Participants were clustered according to their (co)variation around the grand mean on each item of the Kessler Psychological Distress Scale (K10). Next, to evaluate cluster differences, semi-parametric network models were fitted in each cluster and node centrality indices and network density measures were compared.
A five-cluster model was obtained from the cluster analyses. Network density varied across clusters, and was highest for the cluster of people with the lowest K10 severity ratings. In three cluster networks, depressive symptoms (e.g. feeling depressed, restless, hopeless) had the highest centrality. In the remaining two clusters, symptom networks were characterised by a higher prominence of somatic symptoms (e.g. restlessness, nervousness).
Finding data-driven subtypes based on psychological distress using non-parametric methods can be a fruitful approach, yielding clusters of persons that differ in illness severity as well as in the structure and strengths of inter-symptom relationships.
Introduction: Pulmonary embolism (PE) is a treatable condition, with a low mortality rate (of around 1% in those who are diagnosed with the condition). The risk of recurrent PE is well managed with long term anticoagulation. Past literature suggests that patients who are diagnosed with PE can go on to experience existential anxiety and symptoms suggestive of post-traumatic stress disorder (PTSD). This study aimed to evaluate the mental and emotional experiences of PE patients through the lens of PTSD, and the factors involved in psychological distress following a PE diagnosis. Methods: Semi-structured interviews were conducted with PE patients at the Juravinski Hospital thrombosis clinic in Hamilton, Ontario. Interview questions were based on DSM-5 criteria of PTSD and relevant existing literature. The transcripts were analyzed by two researchers based on an approach that considers both the content of patients’ accounts as well as the way that patients choose to interpret and deliver those accounts, to develop major themes associated with psychological distress. Results: A total of 37 patients, ranging from 28 to 85 years of age, were interviewed. The patients’ accounts suggested that the manner in which a PE diagnosis was delivered by an emergency physician was a significant factor in the degree to which they experienced psychological distress. For example, patients reported focusing on words suggesting that they were ‘a ticking time-bomb’ or that ‘a lot of people don't get through this,’ which introduced a degree of panic. A number of patients continued to focus on these words, months or years after their diagnosis. Some feared that they could have recurrent PE which could lead to death. Diagnoses that were delivered calmly with thorough explanations of why a patient experienced PE-related symptoms and how they will be treated, helped to minimize any subsequent anxiety. Patients initially misdiagnosed with an alternative condition in the ED also expressed feelings of anxiety and distress. The presence of physically and mentally distressing symptoms was also a factor which contributed to mental distress and anxiety regarding a PE recurrence. Conclusion: Caution should be taken in the delivery of PE diagnosis in the emergency department. Over-emphasis on the severity and life-threatening nature of PE should be avoided to reduce psychological distress.
Introduction: The number of seniors presenting to emergency departments after a fall is increasing. Head injury concerns in this population often leads to a head CT scan. The CT rate among physicians is variable and the reasons for this are unknown. This study examined the role of patient characteristics and country of practice in the decision to order a CT. Methods: This study used a case-based survey of physicians across multiple countries. Each survey included 9 cases pertaining to an 82-year old man who falls. Each case varied in one aspect compared to a base case (aspirin, warfarin, or rivaroxaban use, occipital hematoma, amnesia, dementia, and fall with no head trauma). For each case, participants indicated how “likely” they were to order a head CT scan, measured on a 100-point scale. A response of 80 or more was defined a priori as ‘likely to order a CT scan’. The survey was piloted among emergency residents for feedback on design and comprehension, and was published in French and English. Recruitment was through the Canadian Association of Emergency Physicians, Twitter and CanadiEM. For each case we compared the proportion of physicians who were ‘likely to scan’ with relative to the base case. We also compared the proportion of participants who were ‘likely to scan’ each case in the USA, UK and Australia, relative to Canada. Results: Data was collected from 484 respondents (Canada-308, USA-64, UK-67, Australia-27, and 18 from other countries). Social media distribution limited our ability to estimate of the response rate. Physicians were most likely to scan in the anticoagulation cases (90% likely to order a scan compared to 36% for the base case (p = <0.001)). Other features associated with increased scans were occipital hematoma (48%), multiple falls (68%), and amnesia (68%) (all p < 0.005). Compared to Canada, US physicians were more likely to order CT scans for all cases (p = <0.05). Compared to Canada, UK physicians were significantly less likely to order CT for patients in every case except in the patient with amnesia. Finally, Australian physicians differed from Canada only for the occipital hematoma case where they were significantly more likely to order CT scan. Conclusion: Anticoagulation, amnesia and a history of multiple falls appear to drive the ordering a head CT scan in elderly patients who had fallen. We observed variations in practice between countries. Future clinical decision rules will likely have variable impact on head CT scan rates depending on baseline practice variation.
Introduction: There is an evidence-practice gap between guidelines for diagnosing pulmonary embolism (PE) and emergency physician practice. Computed tomography (CT) scanning is being overused to exclude PE in Canadian emergency departments (EDs) and current guidelines do not fit well with the ED model of patient care. There is a lack of research on patient opinions on PE testing, and a poor physician understanding of patient-specific goals in the ED. We are addressing this by conducting patient interviews to identify patient-specific values and opinions on PE testing in the ED. These will be used to develop patient-centered educational tools which physicians and patients can use to discuss the decision to order a CT PE scan. The aim of this study is to identify patient expectations and priorities on PE testing in the ED. Methods: This qualitative study uses constructivist grounded theory to analyze patient values and opinions on PE testing in ED patients from two hospitals. Participants are screened by monitoring the ED patient tracker. If a patient is being tested for PE, they are approached and consented by a researcher to take part in a 30-minute semi-structured interview. Each interview is transcribed verbatim and independently analyzed by four researchers using constant comparative coding. The researchers meet weekly to compare codes and agree on common coding terms. The codes are grouped into themes, and the interview script is modified to maximize information on emerging themes. From this, major themes with associated subthemes will be derived, each representing an opportunity, barrier or value which must be addressed in our new patient education tools. We have performed 23 interviews and expect to reach theme saturation at 30 interviews. Full results will be available by the 2019 CAEP conference. Results: From the patient interviews conducted so far, we have mapped four major themes: patient satisfaction comes from addressing their primary concern (for example, their pain); patients expect individualized care; patients prefer imaging over clinical examination when testing for PE; and patients expect 100% confidence from their ED physician when given a diagnosis. Conclusion: These four domains will be used to create a new patient-centered approach to PE testing in the ED which will include physician education, patient information and organizational changes to patient processing. This study incorporates evidence-based medicine with ethical and social implications to improve patient outcomes.
Introduction: The Canadian population is aging and an increasing proportion of emergency department (ED) patients are seniors. ED visits among seniors are frequently instigated by a fall at home. Some of these patients develop intracranial hemorrhage (ICH) because of falling. There has been little research on the frequency of ICH in elderly patients who fall, and on which clinical factors are associated with ICH in these patients. The aim of this study was to identify the incidence of ICH, and the clinical features which are associated with ICH, in seniors who present to the ED having fallen. Methods: This was a prospective cohort study conducted in three EDs. Patients were included if they were age >65 years, and presented to the ED within 48 hours of a fall on level ground, off a bed/chair/toilet or down one step. Patients were excluded if they fell from a height, were knocked over by a vehicle or were assaulted. ED physicians recorded predefined clinical findings (yes/no) before any head imaging was done. Head imaging was done at the ED physician's discretion. All patients were followed for 6 weeks (both by telephone call and chart review at 6 weeks) for evidence of ICH. Associations between baseline clinical findings and the presence of ICH were assessed with multivariable logistic regression. Results: In total, 1753 patients were enrolled. The prevalence of ICH was 5.0% (88 patients), of whom 74 patients had ICH on the ED CT scan and 14 had ICH diagnosed during follow-up. 61% were female and the median age was 82 (interquartile range 75-88). History included hypertension in 76%, diabetes in 29%, dementia in 27%, stroke/TIA in 19%, major bleeding in 11% and chronic kidney disease in 11%. 35% were on antiplatelet therapy and 25% were on an anticoagulant. Only 4 clinical variables were independently associated with ICH: bruise/laceration on the head (odds ratio (OR): 4.3; 95% CI 2.7-7.0), new abnormalities on neurological examination (OR: 4.4; 2.4-8.1), chronic kidney disease (OR: 2.4; 1.3-4.6) and reduced GCS from baseline (OR: 1.9; 1.0-3.4). Neither anticoagulation (OR: 0.9; 0.5-1.6) nor antiplatelet use (OR: 1.1; 0.6-1.8) appeared to be associated with ICH. Conclusion: This prospective study found a prevalence of ICH of 5.0% in seniors after a fall, and that bruising on the head, abnormal neurological examination, abnormal GCS and chronic kidney disease were predictive of ICH.
Introduction: Falls are a common presentation to the emergency department among geriatric patients. The incidence of intracranial bleeding following a fall is unclear and approach to ordering a CT head scan is not standardized. The aim of this systematic review and meta-analysis was to establish the incidence of intracranial bleeding after a fall in geriatric patients. Methods: The systematic review was registered in PROSPERO. Two authors independently searched Medline and EMBASE (OVID interface) from conception till 20th June 2018. The search combined multiple MESH terms and text words for [falls], [elderly] and [brain injury]. The search was repeated in Google Scholar and recent conference abstracts were reviewed. Studies were included if > 80% of the included patients were > 65 years who presented to the emergency department after a fall on level ground. We excluded studies enrolling select populations (for example trauma team activation, neurosurgical patients or only anticoagulated patients). There were no language restrictions. The random effects model was used to perform a meta-analysis on the incidence of intracranial bleeding in geriatric patients after a fall on level ground. Results: From the 7,043 titles and abstracts, 175 full articles were reviewed and 7 studies, including 6758 patients, were included in the analysis. 2/7 studies were prospective. The studies varied in their inclusion criteria with 3/7 studies only including patients with normal neurological testing. Most retrospective studies included patients if they had a CT head scan. Neither prospective study imaged all patients but both followed the patients for a delayed diagnosis of intracranial bleeding. Risk of bias was moderate or high for the majority of studies. The random effects pooled incidence of intracranial bleeding was 5.2% (95% CI 2.8 – 8.2%), I2 96%. Conclusion: Around 1 in 20 geriatric patients who present to the emergency department after a fall have intracranial bleeding. This point estimate can be used to calculate sample size requirements for future studies on intracranial bleeding in this population.
The challenges raised in this article are not with information theory per se, but the assumptions surrounding it. Neuroscience isn't sufficiently critical about the appropriate ‘receiver’ or ‘channel’, focuses on decoding ‘parts’, and often relies on a flawed ‘veridicality’ assumption. If these problematic assumptions were questioned, information theory could be better directed to help us understand how the brain works.
Introduction: Translating research evidence into routine clinical practice in emergency departments (EDs) often requires changing the behavior(s) of one or more member of the healthcare team. Changing strongly entrenched behavior patterns or occasional behaviors that are impacted by psychological, social or environmental factors can be challenging. We conducted a systematic review of the literature to identify implementation strategies that have been evaluated to change ED provider behavior and promote the uptake of evidence in emergency practice settings. Methods: The following databases were systematically searched from inception to 2017 with the support of a library scientist: MEDLINE, CINAHL, Embase and Cochrane CENTRAL. We also manually searched the last 5 years of Annals of Emergency Medicine, Canadian Journal of Emergency Medicine, and Implementation Science. Studies were assessed by two independent reviewers and retained if they included one or more of the implementation strategies listed in the Cochrane Effective Practice and Organization of Care (EPOC) Taxonomy, targeted any health care provider working in any type of emergency department. The Cochrane Risk of Bias tool was used to assess study quality. Results: Following review of 13,000 title and abstracts, 33 studies met the inclusion criteria. The majority of included studies were randomized control trials (N=32) and 50% were published in the last seven years. Although poorly described, interventions targeted either physicians (n=12), nurses (n=8), pharmacists (n=1) or multi-disciplinary teams (n=12). Common behavioral targets included compliance with practice guidelines, test ordering and prescribing. According to the EPOC Taxonomy most implementation strategies were multi-component and could be categorized as either educational materials/meetings and/or reminders. Only one study author reported using evidence to inform the design of the implementation strategy. Effect sizes varied across relevant study outcomes but the direction of effect was positive in 22/33 included studies. Heterogeneity of study interventions and outcomes precluded meta-analysis. Conclusion: To strengthen the evidence base regarding implementation strategies that promote provider behavior change across different ED contexts, there is a critical need to improve both the design and reporting of implementation strategies in ED research.
Introduction: Current treatment guidelines advocate for the aggressive management of both high-risk and subsets of moderate-risk pulmonary embolism (PE) with fibrinolytic therapy. However, there is limited evidence on the risks and benefits of fibrinolytic therapy in PE, with mortality improvement still to be proven. This study aimed to report the incidence of major bleeding and death after thrombolysis for PE. Methods: A health records review was performed on data from two hospitals between 2007 and 2017. Pharmacy identified all patients who had received either alteplase or tenecteplase. Trained abstractors reviewed each chart to determine the indication for thrombolytic therapy. Patients were included if they received systemic thrombolysis for diagnosed or presumed PE. Data was extracted on 30-day mortality, International Society of Thrombosis and Hemostasis defined major bleeding within 30 days, premorbid anticoagulant and antiplatelet prescription, age, sex, comorbidities, renal function, history of bleeding, type and dose of thrombolytic and category of PE (high or moderate risk). Results: 1534 patients were identified, of which 72 received systemic thrombolysis for PE. The median age was 57, 34 were male, 17 with a history of venous thrombosis and 12 with cancer. Fifty-four were classified as having high-risk PE, of whom 39 received cardiopulmonary resuscitation (CPR) when thrombolysis was administered. Formal confirmatory imagining for PE was obtained in only 23/39 patients who were in cardiac arrest. Eighteen patients were classified as moderate-risk PE. The incidence of major bleeding was 28/54 (52%, 95% CI 39-65%), and 3/18 (17%, 95% CI 6-39%) for the high and moderate risk groups respectively. There were 4 intracranial bleeds, all in the high-risk PE group. The only significant predictor of major bleeding was the need for CPR at the point of administration of the thrombolytic agent (OR 2.6, 95% CI 1.0-7.5, adjusted for age). Thirty-four patients died within 30 days (47%, 95% CI 36-59%), all in the high-risk PE group. Death was not associated with any demographic variable on univariate analysis. Death occurred in 28/39 (72%, 95%CI 56-83%) patients who received CPR and 6/33 (18%, 95% CI 9-34%) who did not. Conclusion: We found a high incidence of 30-day major bleeding and death following administration of thrombolysis for PE which will help inform future prognostic discussions in our institution.
Introduction: The diagnostic process is wrought with potential sources of error. Psychologists seek to coach physicians to refine their cognition. Researchers try to create cognitive scaffolds to guide decision-making. Physicians however, are caught in middle between their own daily cognitive processes and these external theories that might influence their behaviour. Few attempts have been made to understand how experienced clinicians integrate guidelines or clinical decision rules (CDRs) into their decision-making. We sought to explore experienced clinicians decision-making via a simulated exercise, to develop a model of how physicians integrate CDRs into their diagnostic thinking. Methods: From July 2015-March 2016, 16 practicing emergency physicians (EPs) were interviewed via a think aloud protocol study. Six cases were constructed and video recorded as prompts to spur the clinicians to think aloud and describe their approach to the cases. Cases were designed to be slightly suggestive for pulmonary embolism or deep vein thrombosis, since these conditions are associated with CDRs. Using a constructivist grounded theory analysis, three investigators independently reviewed the transcripts from the interviews, meeting regularly to discuss emergent themes and subthemes until sufficiency was reached. Disagreements about themes were resolved by discussion and consensus. Results: Our analysis suggests that physicians engage in an iterative process when they are faced with undifferentiated chest pain and leg pain cases. After generating an original differential diagnosis, EPs engage in an iterative diagnostic process. They flip between hypothesis-driven data collection (e.g. history, physical exam, tests) and analysis of this data, and use this process to weigh probabilities of various diagnoses. EPs only apply CDRs once they are sufficiently suspicious of a diagnosis requiring guidance from a CDR and when they experience diagnostic uncertainty or wish to bolster their decision with evidence. Conclusion: EP cognition around diagnosis is a dynamic and iterative process, and may only peripherally integrate relevant CDRs if a threshold level of suspicion is met. Our findings may be useful for improving knowledge translation of CDRs and prevent diagnostic error.
Introduction: Free Open Access Medical education (FOAM) resources have been developed using various needs assessment methods. We describe a storytelling exercise used to identify unperceived medical expert learning needs, which also resulted in the emergence of unknown learning needs within intrinsic physician roles. Methods: A FOAM curriculum was created for thrombosis based on an online needs assessment comprised of a topic listing, case scenarios, and a storytelling exercise. In the storytelling exercise, learners described i) a difficult case in thrombosis, and ii) why that case was difficult. In this qualitative description study, we performed a secondary thematic analysis of this storytelling data, coded for CanMEDS 2015 intrinsic roles. Two investigators independently coded transcripts to iteratively generate a coding framework. Results: 143 respondents completed the storytelling exercise. All responses yielded a gap in medical expertise, while 25 (17.5%) described an additional intrinsic theme. Learning needs in all six intrinsic roles were identified. The most commonly cited learning needs were in the Leader (recognizing how resource allocation impacts healthcare), Communicator (communicating expert knowledge with patients), and Collaborator (unclear communication between providers) domains. Participants who described an intrinsic learning need were primarily from emergency medicine (21/25, 84.0%). These excerpts were notable for how they expressed the complexity and affective components of medicine. Conclusion: Storytelling exercises can highlight context, attitudes, and relationships which provide depth to needs assessments. These narratives are a novel method of capturing emergent learning needs, which may be unknown to learner and faculty (Johari window). These intrinsic learning needs may ultimately be used to enrich learner-centered curricula.
Introduction: Cognitive processing theories postulate that decision making depends on both fast and slow thinking. Experienced physicians (EPs) make diagnoses quickly and with less effort by using fast, intuitive thinking, whereas inexperienced medical students rely on slow, analytical thinking. This study used a cognitive task analysis to examine EPs cognitive processes and ability to provide knowledge translation to learners. Methods: A novel mind mapping approach was used to examine how EPs translate their clinical reasoning to learners, when evaluating a patient for a possible venous thromboembolism (VTE). Nine EPs were interviewed and shown two different videos of a medical student patient interview (randomized from six possible videos). Results: EPs were asked to demonstrate their clinical approach to the scenario using a mind map, assuming they were teaching a learner in the Emergency Department. EPs were later re-interviewed to examine response stability, and given the opportunity to make clarifying or substantive mind map modifications. Maps were broken into component pieces and analyzed using mixed-methods techniques. A mean of 15.7 component pieces were identified within each mind map (standard deviation (SD) 7.8). Maps were qualitatively coded, with a mean of 2.8 clarifying amendments (e.g. adding a time course caveat) (SD 1.5-5.75) and 4.4 substantive modifications (e.g. changing the flow of the map) (SD 2-5). Conclusion: Resulting mind maps displayed significant heterogeneity in teaching points and the degree to which EPs used slow thinking. EPs frequently made fast thinking jumps, although learners could prompt slow thinking by questioning unclear points. This is particularly important as learners engage in cognitive apprenticeship throughout their training. An improved understanding of EPs cognitive processes through mind mapping will allow learners to improve their own clinical reasoning (Merrit et al., 2017). Educating EPs on these processes will allow modification of their teaching styles to better suit learners.
Introduction: The accuracy of ultrasound (US) for diagnosing lower extremity deep vein thrombosis (DVT) in non-pregnant patients has been well validated. However, in pregnant women with suspected DVT and an initial negative US (with imaging of the iliac veins), serial US is recommended. We aimed to determine the ability of single negative US to exclude DVT in symptomatic pregnant women. Methods: Two authors independently reviewed the following databases: MEDLINE, PubMed and EMBase from inception until May 2017. Three authors reviewed all full text papers and data were extracted from included studies by four authors. An overlap among study populations was identified in 4 of the manuscripts, all from one multicentre Canadian study. Two authors performed data re-extraction from the hard copy research charts from this study. We assessed the risk of bias using the CLARITY group tool for prognostic studies. Results: Of 109 potentially relevant articles, 8 studies (7 prospective studies and 1 retrospective) were included. Risk of bias was low for the included populations, and low or moderate for method of measurement and for completeness of follow up. A total of 635 pregnant patients with symptoms of DVT had an initial negative US examination. Of those, 6 had positive DVT during serial US (0.94%) and 3 developed DVT during 3-month follow-up after serial ultrasound (0.47%). Using random-effects model, the pooled false negative rate of a single ultrasound was 1.27% (95% confidence interval, 0.42 to 2.56), I2= 27%. Conclusion: The false negative rate of a single ultrasound with iliac vein imaging for DVT in pregnancy is low. Our results will help inform shared decision making around planning repeat ultrasound scans in these patients.
Introduction: Diagnosing pulmonary embolism (PE) can be challenging because the signs and symptoms are often non-specific. Studies have shown that evidence-based algorithms are not always adhered to in the Emergency Department (ED) and are often not used correctly, which leads to unnecessary CT scanning. The YEARS diagnostic algorithm, consisting of three items (clinical signs of deep vein thrombosis, hemoptysis, and whether pulmonary embolism is the most likely diagnosis) and D-dimer, is a novel and simplified way to approach suspected acute PE. The purpose of this study was to 1) evaluate the use of the YEARS algorithm in the ED and 2) to compare the rates of testing for PE if the YEARS algorithm was used. Methods: This was a health records review of ED patients investigated for PE at two emergency departments over a two-year period (April 2013-March 2015). Inclusion criteria were ED physician ordered CT pulmonary angiogram, ventilation-perfusion scan, or D-dimer for investigation of PE. Patients under the age of 18 and those without a D-dimer test were excluded. PE was considered to be present during the emergency department visit if PE was diagnosed on CT or VQ (subsegmental level or above), or if the patient was subsequently found to have PE or deep vein thrombosis during the next 30 days. Trained researchers extracted anonymized data. The rate of CT/VQ imaging and the false negative rate was calculated. Results: There were 1,163 patients that were tested for PE and 1,083 patients were eligible for our analysis. Of the total, 317/1,083 (29.3%; 95%CI 26.6-32.1%) had CT/VQ imaging for PE, and 41/1,083 (3.8%; 95%CI 2.8-5.1%) patients were diagnosed with PE at baseline. Three patients had a missed PE, resulting in a false negative rate of 0.4% (95%CI 0.1-1.2%). If the YEARS algorithm was used, 211/1,083 (19.5%; 95%CI 17.2-22.0%) would have required imaging for PE. Of the patients who would not have required imaging according to the YEARS algorithm, 8/872 (0.9%; 95%CI 0.5-1.8%) would have had a missed PE. Conclusion: If the YEARS algorithm was used in all patients with suspected PE, fewer patients would have required imaging with a small increase in the false negative rate.
Introduction: The proportion of Canadians receiving anticoagulation medication is increasing. Falls in the elderly are the most common cause of minor head injury and an increasing proportion of these patients are prescribed anticoagulation. Emergency department (ED) guidelines advise performing a CT head scan for all anticoagulated head injured patients, but the risk of intracranial hemorrhage (ICH) after a minor head injury (patients who have a Glasgow comma score (GSC) of 15) is unclear. We conducted a systematic review and meta-analysis to determine the point incidence of ICH in anticoagulated ED patients presenting with a minor head injury. Methods: We systematically searched Pubmed, EMBASE, Cochrane database, DARE, google scholar and conference abstracts (May 2017). Experts were contacted. Meta-Analyses and Systematic Reviews of Observational Studies (MOOSE) guidelines were followed with two authors reviewing titles, four authors reviewing full text and four authors performing data extraction. We included all prospective studies recruiting consecutive anticoagulated ED patients presenting with a head injury. We obtained additional data from the authors of the included studies on the subset of GCS 15 patients. We performed a meta-analysis to estimate the point incidence of ICH among patients with a GCS score of 15 using a random effects model. Results: A total of five studies (and 4,080 GCS 15, anticoagulated patients) from the Netherlands, Italy, France, USA and UK were included in the analysis. One study contributed 2,871 patients. Direct oral anticoagulants were prescribed in only 60 (1.5%) patients. There was significant heterogeneity between studies with regards to mechanism of injury, CT scanning and follow up method (I2 =93%). The random effects pooled incidence of ICH was 8.9% (95% CI 5.0-13.8%). Conclusion: We found little data to reflect contemporary anticoagulant prescribing practice. Around 9% of warfarinized patients with a minor head injury develop ICH. Future studies should evaluate the safety of selective CT head scanning in this population.
Introduction: Diagnosing pulmonary embolism (PE) can be challenging because the signs and symptoms are often non-specific. Studies have shown that evidence-based algorithms are not always adhered to in the Emergency Department (ED), which leads to unnecessary CT scanning. The pulmonary embolism rule-out criteria (PERC) can identify patients who can be safely discharged from the ED without further investigation for PE. The purpose of this study is to evaluate the use of the PERC rule in the ED and to compare the rates of testing for PE if the PERC rule was used. Methods: This was a health records review of ED patients investigated for PE at two emergency departments over a two-year period (April 2013-March 2015). Inclusion criteria were ED physician ordered CT pulmonary angiogram, ventilation-perfusion scan, or D-dimer for investigation of PE. Patients under the age of 18 were excluded. PE was considered to be present during the emergency department visit if PE was diagnosed on CT or VQ (subsegmental level or above), or if the patient was subsequently found to have PE or deep vein thrombosis during the next 30 days. Trained researchers extracted anonymized data. The rate of CT/VQ imaging and the negative predictive value was calculated. Results: There were 1,163 patients that were tested for PE and 1,097 patients were eligible for our analysis. Of the total, 330/1,097 (30.1%; 95%CI 27.4-32.3%) had CT/VQ imaging for PE, and 48/1,097 (4.4%; 95%CI 3.3-5.8%) patients were diagnosed with PE. 806/1,097 (73.5%; 95%CI 70.8-76.0%) were PERC positive, and of these, 44 patients had a PE (5.5%; 95%CI 4.1-7.3%). Conversely, 291/1,097 (26.5%; 95%CI 24.0-29.2%) patients were PERC negative, and of these, 4 patients had a PE (1.4%; 95%CI 0.5-3.5%). Of the PERC negative patients, 291/291 (100.0%; 95%CI 98.7-100.0%) had a D-dimer test done, and 33/291 (11.3%; 95%CI 8.2-15.5%) had a CT angiogram. If PERC was used, CT/VQ imaging would have been avoided in 33/1,097 (3%; 95%CI 2.2-4.2%) patients and the D-dimer would have been avoided in 291/1,097 (26.5%; 95%CI 24.0-29.2%) patients. Conclusion: If the PERC rule was used in all patients with suspected PE, fewer patients would have further testing. The false negative rate for the PERC rule was low.