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There is a strong overlap between imagined and hallucinatory phenomena in the sense that both are internal representations of external things that are not present at the time. Relationships between hallucinations and wider aspects of imagination are complex and individual, with a lack of systematic evidence. There appears to be a close relationship between the brain areas responsible for veridical, imagined, and hallucinatory perception, though more data is needed. However, how activity varies within and outside these areas in order to create different types of imagination is not at all clear. Drug effects provide one avenue for systematically exploring links between hallucinations and imagination. Drugs that cause hallucinations also tend to affect wider imagination and creativity, though results are variable and are open to alternative explanations. Nevertheless, these effects suggest that wider, non-perceptual, brain systems are involved in the generation of imaginative responses to hallucinations. Future investigations need to define imagination more closely, have tighter designs, and combine approaches.
One in four cases of acute aortic syndrome are missed. This national survey examined Canadian Emergency physicians’ opinion on risk stratification, the need for a clinical decision aid to risk stratify patients, and the required sensitivity of such a tool.
We surveyed 1,556 members of the Canadian Association of Emergency Physicians. We used a modified Dillman technique with a prenotification email and up to three survey attempts using electronic mail. Physicians were asked 21 questions about demographics, importance of certain high-risk features, investigation options, threshold for investigation, and if a clinical decision tool is required
We had a response rate of 32%. Respondents were 66% male, and 49% practicing >10 years, with 59% in an academic teaching hospital. A total of 93% reported a need for a clinical decision aid to risk stratify for acute aortic syndrome. A total of 99.6% of physicians were pragmatic accepting a non-zero miss-rate, two-thirds accepting <1%, and the remaining accepting a higher miss-rate.
Our national survey determined that emergency physicians would use a highly sensitive clinical decision aid to determine which patients are at low, medium, or high-risk for acute aortic syndrome. The majority of clinicians have a low threshold (<1%) for investigating for acute aortic syndrome, but accept that a zero miss-rate is not feasible.
We propose the nasal administration of calcium-enriched physiological salts as a new hygienic intervention with possible therapeutic application as a response to the rapid and tenacious spread of COVID-19. We test the effectiveness of these salts against viral and bacterial pathogens in animals and humans. We find that aerosol administration of these salts to the airways diminishes the exhalation of the small particles that face masks fail to filter and, in the case of an influenza swine model, completely block airborne transmission of disease. In a study of 10 human volunteers (5 less than 65 years and 5 older than 65 years), we show that delivery of a nasal saline comprising calcium and sodium salts quickly (within 15 min) and durably (up to at least 6 h) diminishes exhaled particles from the human airways. Being predominantly smaller than 1 μm, these particles are below the size effectively filtered by conventional masks. The suppression of exhaled droplets by the nasal delivery of calcium-rich saline with aerosol droplet size of around 10 μm suggests the upper airways as a primary source of bioaerosol generation. The suppression effect is especially pronounced (99%) among those who exhale large numbers of particles. In our study, we found this high-particle exhalation group to correlate with advanced age. We argue for a new hygienic practice of nasal cleansing by a calcium-rich saline aerosol, to complement the washing of hands with ordinary soap, use of a face mask, and social distancing.
Acute aortic dissection (AAD) is a time sensitive, difficult to diagnose, aortic emergency. We sought to explore the quality of history taking in AAD and assess its impact on misdiagnosis.
We studied a retrospective cohort of patients >18 years old who presented to two tertiary care emergency departments from January 1st 2004 – December 31st 2012 and were diagnosed with an acute aortic dissection (AAD) on CT, MRI or TEE. Trained reviewers’ extracted data using a standardized data collection form. The definitions of 5 pain characteristics – character, onset, duration, quality, and radiation were defined a priori.
Data were collected for 194 cases of acute aortic dissection with a mean age of 65(SD 14.1) and 66.7% male, 34(17.6%) missed on initial presentation. Only 20(14.8%) patients were asked all 5 questions. The most common initial incorrect diagnosis were acute coronary syndrome (16, 47%), pulmonary embolism (5, 14.7%) and stroke (4, 11.7%). If <2 questions were asked 1 in 5 cases were missed, 4 times greater than if >2 were asked (P < 0.01).
Clinicians should ask and document the character, onset, duration, radiation and severity of pain in any patient presenting with chest, abdominal or flank pain. A focused history still remains the keystone to reducing misdiagnosis.
Although procedural sedation for cardioversion is a common event in emergency departments (EDs), there is limited evidence surrounding medication choices. We sought to evaluate geographic and temporal variation in sedative choice at multiple Canadian sites, and to estimate the risk of adverse events due to sedative choice.
This is a secondary analysis of one health records review, the Recent Onset Atrial Fibrillation or Flutter-0 (RAFF-0 [n=420, 2008]) and one prospective cohort study, the Recent Onset Atrial Fibrillation or Flutter-1 (RAFF-1 [n=565, 2010 – 2012]) at eight and six Canadian EDs, respectively. Sedative choices within and among EDs were quantified, and the risk of adverse events was examined with adjusted and unadjusted comparisons of sedative regimes.
In RAFF-0 and RAFF-1, the combination of propofol and fentanyl was most popular (63.8% and 52.7%) followed by propofol alone (27.9% and 37.3%). There were substantially more adverse events in the RAFF-0 data set (13.5%) versus RAFF-1 (3.3%). In both data sets, the combination of propofol/fentanyl was not associated with increased adverse event risk compared to propofol alone.
There is marked variability in procedural sedation medication choice for a direct current cardioversion in Canadian EDs, with increased use of propofol alone as a sedation agent over time. The risk of adverse events from procedural sedation during cardioversion is low but not insignificant. We did not identify an increased risk of adverse events with the addition of fentanyl as an adjunctive analgesic to propofol.
Enlist™ cotton contains the aad-12 and pat genes that confer resistance to 2,4-D and glufosinate, respectively. Thirty-three field trials were conducted focused on Enlist cotton injury from glufosinate as affected by cotton growth stage, application rate, and single or sequential applications. Maximum injury from a single application of typical 1X (542 g ae ha-1) and 2X use rates was 3 and 13%, respectively, regardless of growth stage. Injury from sequential applications of 1X or 2X rates was equivalent to single applications. Similar injury was observed with four commercial formulations of glufosinate. Cotton yield was never affected by glufosinate. This research demonstrates Enlist™ cotton has robust resistance to glufosinate at rates at least twice the typical use rate when applied once or twice at growth stages ranging from 2 to 12 leaves.
In 2011, Canada had a foreign-born population of approximately 6,775,800. They represented 20.6% of the total population. Immigrants possess characteristics that reduce the use of primary care. This is thought to be, in part, due to a lower education level, employment, and better health status. Our objective was to assess whether, in an immigrant population without a primary care physician, similar socioeconomic factors would also reduce the likelihood of using the emergency department compared to a non-immigrant population without primary care.
Data regarding individuals ≥ 12 years of age from the Canadian Community Health Survey from 2007 to 2008 were analysed (n=134,073; response rate 93%). Our study population comprised 15,554 individuals identified without a primary care physician who had a regular place for medical care. The primary outcome was emergency department as a regular care access point. Socioeconomic variables included employment, health status, and education. Covariates included chronic health conditions, mobility, gender, age, and mental health. Weighted logistic regression models were constructed to evaluate the importance of individual risk factors.
The sample of 15,554 (immigrants n=1,767) consisted of 57.3% male and 42.7% female respondents from across Canada. Immigrants were less likely than Canadian-born respondents to use the emergency department as a regular access point for health care (odds ratio=0.48 [95% CI 0.40 – 0.57]). Adjusting for health, education, or employment had no effect on this reduced tendency (odds ratio=0.47 [95% CI 0.38 – 0.58]).
In a Canadian population without a primary care physician, immigrants are less likely to use the emergency department as a primary access point for care than Canadian-born respondents. However, this effect is independent of previously reported social and economic factors that impact use of primary care. Immigration status is an important but complex component of racial and ethnic disparity in the use of health care in Canada.
To assess the effects of aripiprazole once-monthly 400 mg (AOM 400) on clinical symptoms and global improvement in schizophrenia after switching from an oral antipsychotic.
In a multicenter, open-label, mirror-image, naturalistic study in patients with schizophrenia (>1 year, Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision [DSM-IV-TR] criteria), changes in efficacy measures were assessed during prospective treatment (6 months) with AOM 400 after switching from standard-of-care oral antipsychotics. During prospective treatment, patients were cross-titrated to oral aripiprazole monotherapy (1–4) weeks followed by open-label AOM 400 (24 weeks). Mean change from baseline of the open-label AOM 400 phase in Positive and Negative Syndrome Scale (PANSS) scores (total, positive and negative subscales) and Clinical Global Impression–Severity (CGI-S) scores; mean CGI–Improvement (CGI-I) score; and proportion of responders (≥30% decrease from baseline in PANSS total score or CGI-I score of 1 [very much improved] or 2 [much improved]) were assessed.
PANSS and CGI-S scores improved from baseline (P<0.0001) and CGI-I demonstrated improvement at all time points. By the end of the study, 49.0% of patients were PANSS or CGI-I responders.
In a community setting, patients with schizophrenia who were stabilized at baseline and switched to AOM 400 from oral antipsychotics showed clear improvements in clinical symptoms.
Approximately 4.3 million Canadians are without a primary care physician, of which 13% choose the emergency department (ED) as their regular access point to health care. We sought to identify factors associated with preferential ED use over other health services. We hypothesized that socioeconomic barriers (i.e., employment, health status, education) to primary care would also prevent access to ED alternatives.
Data from the Canadian Community Health Survey, 2007 to 2008, were analysed (N=134,073; response rate 93.5%). Our study population comprised 14,091 individuals identified without a primary care physician. Socioeconomic variables included employment, health, and education. Covariates included chronic health conditions, immigrant status, gender, age, and mental health. Prevalence estimates and 95% confidence intervals (CIs) for each variable were calculated. Weighted logistic regression models were constructed to evaluate the importance of individual risk factors and their interactions after adjustment for relevant covariates.
The sample comprised 57.2% males from across Canada. Employment (OR 0.73 [95% CI: 0.59-0.90]), good health (OR 0.73 [95% CI 0.57-0.88]), and post-secondary education (OR 0.68 [95% CI 0.53-0.88]) reduced respondents use of the ED. The reduced odds of ED use were independent of chronic conditions, mental health, gender, poor mobility, province, and age.
Low socioeconomic status dictates preferential ED use in those without a primary care physician. Specific policy and system development targeting this at-risk population are indicated to alter ED use patterns in this population.
We sought to conduct a major objective of the CAEP Academic Section, an environmental scan of the academic emergency medicine programs across the 17 Canadian medical schools.
We developed an 84-question questionnaire, which was distributed to academic heads. The responses were validated by phone by the lead author to ensure that the questions were answered completely and consistently. Details of pediatric emergency medicine units were excluded from the scan.
At eight of 17 universities, emergency medicine has full departmental status and at two it has no official academic status. Canadian academic emergency medicine is practiced at 46 major teaching hospitals and 13 specialized pediatric hospitals. Another 69 Canadian hospital EDs regularly take clinical clerks and emergency medicine residents. There are 31 full professors of emergency medicine in Canada. Teaching programs are strong with clerkships offered at 16/17 universities, CCFP(EM) programs at 17/17, and RCPSC residency programs at 14/17. Fourteen sites have at least one physician with a Master’s degree in education. There are 55 clinical researchers with salary support at 13 universities. Sixteen sites have published peer-reviewed papers in the past five years, ranging from four to 235 per site. Annual budgets range from $200,000 to $5,900,000.
This comprehensive review of academic activities in emergency medicine across Canada identifies areas of strengths as well as opportunities for improvement. CAEP and the Academic Section hope we can ultimately improve ED patient care by sharing best academic practices and becoming better teachers, educators, and researchers.
Nosocomial outbreaks caused by Salmonella are rare. We describe the investigation and control of a cluster of novel extended-spectrum β-lactamase (ESBL) Salmonella enterica serotype Isangi in a hospital in southeastern Michigan.
An epidemiologic investigation, including case-control study, assessment of infection control practices and environmental cultures, was performed to identify modes of transmission. Healthcare workers (HCWs) exposed to case patients were screened. Strain relatedness was determined using pulsed-field gel electrophoresis (PFGE); ESBL confirmation was conducted using real-time PCR. Control measures were implemented to prevent further transmission.
Between September 2 and October 22, 2015, 19 surgical patients, including 10 organ transplant recipients and 1 HCW, had positive S. Isangi cultures. Of these case patients and HCW, 13 had gastroenteritis, 2 had bacteremia, 1 had surgical-site infection, and 4 were asymptomatic. Pulsed-field gel electrophoresis (PFGE) showed 89.5% similarity among the isolates in these cases. Isolates with resistant-phenotypes possessed plasmid-mediated CTX-M15 ESBL. A total of 19 case patients were compared with 57 control participants. Case patients had significantly higher odds of exposure to an intraoperative transesophageal (TEE) probe (adjusted odds ratio 9.0; 95% confidence interval, 1.12–72.60; P=.02). Possible cross-transmission occurred in the HCW and 2 patients. Cultures of TEE probes and the environment were negative. The outbreak ended after removal of TEE probes, modification of reprocessing procedures, implementation of strict infection control practices, and enhanced environmental cleaning.
We report the first nosocomial ESBL S. Isangi outbreak in the United States. Multiple control measures were necessary to interrupt transmission of this gastrointestinal pathogen. Exposure to possibly contaminated TEE probes was associated with transmission. Periodic monitoring of reprocessing procedures of TEE probes may be required to ensure optimal disinfection.
North American studies show bipolar disorder is associated with elevated
rates of problem gambling; however, little is known about rates in the
different presentations of bipolar illness.
To determine the prevalence and distribution of problem gambling in
people with bipolar disorder in the UK.
The Problem Gambling Severity Index was used to measure gambling problems
in 635 participants with bipolar disorder.
Moderate to severe gambling problems were four times higher in people
with bipolar disorder than in the general population, and were associated
with type 2 disorder (OR = 1.74, P = 0.036), history of
suicidal ideation or attempt (OR = 3.44, P = 0.02) and
rapid cycling (OR = 2.63, P = 0.008).
Approximately 1 in 10 patients with bipolar disorder may be at moderate
to severe risk of problem gambling, possibly associated with suicidal
behaviour and a rapid cycling course. Elevated rates of gambling problems
in type 2 disorder highlight the probable significance of modest but
unstable mood disturbance in the development and maintenance of such
To characterize the current state of Canadian emergency medicine (EM) resident research and develop recommendations to promote excellence in this area.
We performed a systematic review of MEDLINE, Embase, and ERIC using search terms relevant to EM resident research. We conducted an online survey of EM residency program directors from the Royal College of Physicians and Surgeons of Canada (RCPSC) and College of Family Physicians of Canada (CFPC). An expert panel reviewed these data, presented recommendations at the Canadian Association of Emergency Physicians 2014 Academic Symposium, and refined them based on feedback received.
Of 654 potentially relevant citations, 35 articles were included. These were categorized into four themes: 1) expectations and requirements, 2) training and assessment, 3) infrastructure and support, and 4) dissemination. We received 31 responses from all 31 RCPSC-EM and CFPC-EM programs. The majority of EM programs reported requiring a resident scholarly project; however, we found wide-ranging expectations for the type of resident research performed and how results were disseminated, as well as the degree of completion expected. Although 93% of RCPSC-EM programs reported providing formal training on how to conduct research, only 53% of CFPC-EM programs reported doing so. Almost all programs (94%) reported having infrastructure in place to support resident research, but the nature of support was highly variable. Finally, there was marked variability regarding the number of resident-published abstracts and manuscripts.
Based on the literature, our national survey, and discussions with stakeholders, we offer 14 recommendations encompassing goals, expectations, training, assessment, infrastructure, and dissemination in order to improve Canadian EM resident research.
We sought to gather a comprehensive list of funding strategies and opportunities for emergency medicine (EM) centres across Canada, and make recommendations on how to successfully fund all levels of research activity, including research projects, staff salaries, infrastructure, and researcher stipends.
We formed an expert panel consisting of volunteers recognized nationally for their scholarly work in EM. First, we conducted interviews with academic leaders and researchers to obtain a description of their local funding strategies using a standardized open-ended questionnaire. Panelists then identified emerging funding models. Second, we listed funding opportunities and initiatives at the provincial, national, and international levels. Finally, we used an iterative consensus-based approach to derive pragmatic recommendations after incorporating comments and suggestions from participants at an academic symposium.
Our review of funding strategies identified four funding models: 1) investigator dependent model, 2) practice plan, 3) generous benefactor, and 4) mixed funding. Recommendations in this document include approaches for research contributors and producers (seven recommendations), for local academic leaders (five recommendations), and for national organizations, such as the Canadian Association of Emergency Physicians (CAEP) (three recommendations).
Funding for research in EM varies across Canada and is largely insecure. We offer recommendations to help facilitate funding for large and small projects, for salary support, and for local and national leaders to advance EM research. We believe that these recommendations will increase funding for all levels of EM research activity, including research projects, staff salaries, infrastructure, and researcher stipends.
Long-acting injectable formulations of antipsychotics are treatment alternatives to oral agents.
To assess the efficacy of aripiprazole once-monthly compared with oral aripiprazole for maintenance treatment of schizophrenia.
A 38-week, double-blind, active-controlled, non-inferiority study; randomisation (2:2:1) to aripiprazole once-monthly 400 mg, oral aripiprazole (10–30 mg/day) or aripiprazole once-monthly 50mg (a dose below the therapeutic threshold for assay sensitivity). (Trial registration: clinicaltrials.gov, NCT00706654.)
A total of 1118 patients were screened, and 662 responders to oral aripiprazole were randomised. Kaplan–Meier estimated impending relapse rates at week 26 were 7.12% for aripiprazole once-monthly 400mg and 7.76% for oral aripiprazole. This difference (−0.64%, 95% CI −5.26 to 3.99) excluded the predefined non-inferiority margin of 11.5%. Treatments were superior to aripiprazole once-monthly 50mg (21.80%, P⩽0.001).
Aripiprazole once-monthly 400mg was non-inferior to oral aripiprazole, and the reduction in Kaplan–Meier estimated impending relapse rate at week 26 was statistically significant v. aripiprazole once-monthly 50 mg.
It is believed that when patients present to the emergency department (ED) with recent-onset atrial fibrillation or flutter (RAFF), controlling the ventricular rate before cardioversion improves the success rate. We evaluated the influence of rate control medication and other variables on the success of cardioversion.
This secondary analysis of a medical records review comprised 1,068 patients with RAFF who presented to eight Canadian EDs over 12 months. Univariate analysis was performed to find associations between predictors of conversion to sinus rhythm including use of rate control, rhythm control, and other variables. Predictive variables were incorporated into the multivariate model to calculate adjusted odds ratios (ORs) associated with successful cardioversion.
A total of 634 patients underwent attempted cardioversion: 428 electrical, 354 chemical, and 148 both. Adjusted ORs for factors associated with successful electrical cardioversion were use of rate control medication, 0.39 (95% confidence interval [CI] 0.21-0.74); rhythm control medication, 0.28 (95% CI 0.15-0.53); and CHADS2 score > 0, 0.43 (95% CI 0.15-0.83). ORs for factors associated with successful chemical cardioversion were use of rate control medication, 1.29 (95% CI 0.82-2.03); female sex, 2.37 (95% CI 1.50-3.72); and use of procainamide, 2.32 (95% CI 1.43-3.74).
We demonstrated reduced successful electrical cardioversion of RAFF when patients were pretreated with either rate or rhythm control medication. Although rate control medication was not associated with increased success of chemical cardioversion, use of procainamide was. Slowing the ventricular rate prior to cardioversion should be avoided.