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Patients with schizophrenia and individuals with schizotypy, a subclinical group at risk for schizophrenia, have been found to have impairments in cognitive control. The Dual Mechanisms of Cognitive Control (DMC) framework hypothesises that cognitive control can be divided into proactive and reactive control. However, it is unclear whether individuals with schizotypy have differential behavioural impairments and neural correlates underlying these two types of cognitive control.
Twenty-five individuals with schizotypy and 26 matched healthy controls (HCs) completed both reactive and proactive control tasks with electroencephalographic data recorded. The proportion of congruent and incongruent trials was manipulated in a classic colour-word Stroop task to induce proactive or reactive control. Proactive control was induced in a context with mostly incongruent (MI) trials and reactive control in a context with mostly congruent (MC) trials. Two event-related potential (ERP) components, medial frontal negativity (MFN, associated with conflict detection) and conflict sustained potential (conflict SP, associated with conflict resolution) were examined.
There was no significant difference between the two groups in terms of behavioural results. In terms of ERP results, in the MC context, HC exhibited significantly larger MFN (360–530 ms) and conflict SP (600–1000 ms) amplitudes than individuals with schizotypy. The two groups did not show any significant difference in MFN or conflict SP in the MI context.
The present findings provide initial evidence for dissociation of neural activation between proactive and reactive cognitive control in individuals with schizotypy. These findings help us understand cognitive control deficits in the schizophrenia spectrum.
The coronavirus disease 2019 (COVID-19) pandemic has led to significant strain on front-line healthcare workers.
In this multicentre study, we compared the psychological outcomes during the COVID-19 pandemic in various countries in the Asia-Pacific region and identified factors associated with adverse psychological outcomes.
From 29 April to 4 June 2020, the study recruited healthcare workers from major healthcare institutions in five countries in the Asia-Pacific region. A self-administrated survey that collected information on prior medical conditions, presence of symptoms, and scores on the Depression Anxiety Stress Scales and the Impact of Events Scale-Revised were used. The prevalence of depression, anxiety, stress and post-traumatic stress disorder (PTSD) relating to COVID-19 was compared, and multivariable logistic regression identified independent factors associated with adverse psychological outcomes within each country.
A total of 1146 participants from India, Indonesia, Singapore, Malaysia and Vietnam were studied. Despite having the lowest volume of cases, Vietnam displayed the highest prevalence of PTSD. In contrast, Singapore reported the highest case volume, but had a lower prevalence of depression and anxiety. In the multivariable analysis, we found that non-medically trained personnel, the presence of physical symptoms and presence of prior medical conditions were independent predictors across the participating countries.
This study highlights that the varied prevalence of psychological adversity among healthcare workers is independent of the burden of COVID-19 cases within each country. Early psychological interventions may be beneficial for the vulnerable groups of healthcare workers with presence of physical symptoms, prior medical conditions and those who are not medically trained.
Schizotypy refers to schizophrenia-like traits below the clinical threshold in the general population. The pathological development of schizophrenia has been postulated to evolve from the initial coexistence of ‘brain disconnection’ and ‘brain connectivity compensation’ to ‘brain connectivity decompensation’.
In this study, we examined the brain connectivity changes associated with schizotypy by combining brain white matter structural connectivity, static and dynamic functional connectivity analysis of diffusion tensor imaging data and resting-state functional magnetic resonance imaging data. A total of 87 participants with a high level of schizotypal traits and 122 control participants completed the experiment. Group differences in whole-brain white matter structural connectivity probability, static mean functional connectivity strength, dynamic functional connectivity variability and stability among 264 brain sub-regions of interests were investigated.
We found that individuals with high schizotypy exhibited increased structural connectivity probability within the task control network and within the default mode network; increased variability and decreased stability of functional connectivity within the default mode network and between the auditory network and the subcortical network; and decreased static mean functional connectivity strength mainly associated with the sensorimotor network, the default mode network and the task control network.
These findings highlight the specific changes in brain connectivity associated with schizotypy and indicate that both decompensatory and compensatory changes in structural connectivity within the default mode network and the task control network in the context of whole-brain functional disconnection may be an important neurobiological correlate in individuals with high schizotypy.
Phytase has long been used to decrease the inorganic phosphorus (Pi) input in poultry diet. The current study was conducted to investigate the effects of Pi supplementation on laying performance, egg quality and phosphate–calcium metabolism in Hy-Line Brown laying hens fed phytase. Layers (n = 504, 29 weeks old) were randomly assigned to seven treatments with six replicates of 12 birds. The corn–soybean meal-based diet contained 0.12% non-phytate phosphorus (nPP), 3.8% calcium, 2415 IU/kg vitamin D3 and 2000 FTU/kg phytase. Inorganic phosphorus (in the form of mono-dicalcium phosphate) was added into the basal diet to construct seven experimental diets; the final dietary nPP levels were 0.12%, 0.17%, 0.22%, 0.27%, 0.32%, 0.37% and 0.42%. The feeding trial lasted 12 weeks (hens from 29 to 40 weeks of age). Laying performance (housed laying rate, egg weight, egg mass, daily feed intake and feed conversion ratio) was weekly calculated. Egg quality (egg shape index, shell strength, shell thickness, albumen height, yolk colour and Haugh units), serum parameters (calcium, phosphorus, parathyroid hormone, calcitonin and 1,25-dihydroxyvitamin D), tibia quality (breaking strength, and calcium, phosphorus and ash contents), intestinal gene expression (type IIb sodium-dependent phosphate cotransporter, NaPi-IIb) and phosphorus excretion were determined at the end of the trial. No differences were observed on laying performance, egg quality, serum parameters and tibia quality. Hens fed 0.17% nPP had increased (P < 0.01) duodenum NaPi-IIb expression compared to all other treatments. Phosphorus excretion linearly increased with an increase in dietary nPP (phosphorus excretion = 1.7916 × nPP + 0.2157; R2 = 0.9609, P = 0.001). In conclusion, corn–soybean meal-based diets containing 0.12% nPP, 3.8% calcium, 2415 IU/kg vitamin D3 and 2000 FTU/kg phytase would meet the requirements for egg production in Hy-Line Brown laying hens (29 to 40 weeks of age).
In this paper, the generation of relativistic electron mirrors (REM) and the reflection of an ultra-short laser off the mirrors are discussed, applying two-dimension particle-in-cell simulations. REMs with ultra-high acceleration and expanding velocity can be produced from a solid nanofoil illuminated normally by an ultra-intense femtosecond laser pulse with a sharp rising edge. Chirped attosecond pulse can be produced through the reflection of a counter-propagating probe laser off the accelerating REM. In the electron moving frame, the plasma frequency of the REM keeps decreasing due to its rapid expansion. The laser frequency, on the contrary, keeps increasing due to the acceleration of REM and the relativistic Doppler shift from the lab frame to the electron moving frame. Within an ultra-short time interval, the two frequencies will be equal in the electron moving frame, which leads to the resonance between laser and REM. The reflected radiation near this interval and corresponding spectra will be amplified due to the resonance. Through adjusting the arriving time of the probe laser, a certain part of the reflected field could be selectively amplified or depressed, leading to the selective adjustment of the corresponding spectra.
Introduction: Patients with poorly-controlled diabetes often visit the emergency department (ED) for treatment of hyperglycemia. While previous qualitative studies have examined the patient experience of diabetes as a chronic illness, there are no studies describing patients’ perceptions of ED care for hyperglycemia. The objective of this study was to explore the patient experience regarding ED hyperglycemia visits, and to characterize perceived barriers to adequate glycemic control post-discharge. Methods: This study was conducted at a tertiary care academic centre in London, Ontario. A qualitative constructivist grounded theory methodology was used to understand the experience of adult patient partners who have had an ED hyperglycemia visit. Patient partners, purposively sampled to capture a breadth of age, sex, disease and presentation frequency were invited to participate in a semi-structured individual interview to probe their experiences. Sampling continued until a theoretical framework representing key experiences and expectations reached sufficiency. Data were collected and analyzed iteratively using a constant comparative approach. Results: 22 patients with type 1 or 2 diabetes were interviewed. Participants sought care in the ED over other options because of their concern of having a potentially life-threatening condition, advice from a healthcare provider or family member, or a perceived lack of convenient alternatives to the ED based on time and location. Participants’ care expectations centred around symptom relief, glycemic control, reassurance and education, and seeking referral to specialist diabetes care post-discharge. Finally, perceived system barriers that challenged participants’ glycemic control included affordability of medical supplies and medications, access to follow-up and, in some cases, the transition from pediatric to adult diabetes care. Conclusion: Patients with diabetes utilize the ED for a variety of urgent and emergent hyperglycemic concerns. In addition to providing excellent medical treatment, ED healthcare providers should consider patients’ expectations when caring for those presenting with hyperglycemia. Future studies will focus on developing strategies to help patients navigate some of the barriers that exist within our current limited healthcare system, enhance follow-up care, and improve short- and long-term health outcomes.
Introduction: Naloxone is recommended for reversing opioid-associated respiratory depression. There is wide variability in emergency department (ED) practice patterns regarding naloxone use, dosing, and observation time post-administration. This study describes the naloxone practice patterns of ED physicians managing suspected opioid overdose patients. Methods: A retrospective chart review was conducted of adult patients (≥ 18 years) presenting to an academic tertiary care centre (consisting of two EDs with an annual census 150,000 visits) in 2017 with suspected opioid overdose who were administered naloxone in the ED. Patients were identified electronically and the following information was abstracted from patient charts: demographics, naloxone dosage and infusion initiation, disposition data, indications for naloxone administration, response to therapy, and adverse effects. Variability in initial and total dose was examined. Initial dose was also compared in those with cardiorespiratory compromise (CPR given, respiratory rate < 8, or desaturation below 89%) using independent samples median tests. Data was analyzed using standard descriptive statistics. Results: 113 patients met inclusion criteria. Indications for naloxone administration were: level of consciousness (50.5%), respiratory depression (4.0%), miosis (1.0%), a combination of factors (19.8%), or undocumented (24.8%). Median initial dose was 0.40 mg (IQR: 0.20-0.40 mg). Median total naloxone administered in the ED was 0.48 mg (IQR: 0.35-1.2 mg). The initial dose resulted in a response in 43.1% of patients, with 36.0% of responding patients later experiencing subsequent respiratory depression. 31% of patients received a naloxone infusion. Initial dose in patients with cardiopulmonary compromise was significantly different only comparing patients who received CPR versus those who did not (median 0.40 mg; IQR: 0.20-0.80 mg; P = 0.019). Four patients experienced emesis following naloxone. Median length of ED stay was 7.0 hours (IQR: 4.0-9.5 hours), and median hospital length of stay was 3.0 days (IQR: 1.0-5.0 days). Median ED observation time prior to discharge was 4.0 hours (IQR: 2.0-8.0 hours). Ultimate disposition home, to the ward, or to the intensive care unit was 47.1%, 42.2%, and 9.8% respectively (1.0% deceased). Conclusion: The dose and usage of naloxone by ED physicians in this study is variable. Further prospective studies are needed to determine the effective naloxone dosing strategy.
Introduction: Extreme heat events due to climate change are becoming increasingly frequent and severe, and may have an impact on human health. Administrative database studies using International Classification of Diseases 10th revision codes (ICD-10) are powerful tools to measure the burden of acute heat illness (AHI) in Canada. We aimed to assess the validity of the coding algorithm for emergency department (ED) encounters for AHI in our region. Methods: Two independent reviewers retrospectively abstracted data from 507 medical records of patients presenting at two EDs in Ontario between May-September 2015-2018. The Gold Standard definition of an AHI is chart-documented heat exposure with a heat related complaint, such as syncope while working outdoors on a hot day. To determine ICD coding algorithm positive predictive value (PPV), records that were previously coded as ICD-10 heat illnesses were compared to the Gold Standard for AHI. To determine sensitivity (Sn), specificity (Sp) and negative predictive values (NPV), the Gold Standard was compared to randomly selected records. A total of 326,702 ED visits were included in study period with 208 having an ICD-10 code related to heat illness. Sample size calculation demonstrated a need to manually review 62 previously coded heat illnesses and 931 random cases, of which 50 and 474 have been reviewed, respectively. In both abstractions, 20% of cases underwent a blinded duplicate review. Results: In our review of 474 random records, 2 cases were identified as AHI but without an appropriate ICD-10 code, 445 were not AHIs, and no cases had been identified as having an AHI ICD-10 inappropriately applied. In our review of 50 previously coded heat illnesses, 34 were found to be appropriately coded and 16 inappropriately coded, as AHI ICD-10. Average patient age and gender of heat illness vs non-heat illness ED presentations were 32 and 48 years of age and 49% and 64% male, respectively. The leading complaint in AHI was heat stroke/exhaustion (39%), followed by headaches (15%), dizziness (9%), shortness of breath (9%) and syncope/presyncope (6%). 76% of all heat illness presentations presented following a period of physical exertion. Conclusion: Final calculation of Sn, Sp, PPV, NPV for the algorithm will occur upon completion of the review. Preliminary results suggest that ICD-10 coding for AHI may be applied correctly in the ED. This study will help to determine if administrative data can accurately be used to measure the burden of heat illness in Canada.
Introduction: Cannabinoid Hyperemesis Syndrome (CHS) in pediatric patients is poorly characterized. Literature is scarce, making identification and treatment challenging. This study's objective was to describe demographics and visit data of pediatric patients presenting to the emergency department (ED) with suspected CHS, in order to improve understanding of the disorder. Methods: A retrospective chart review was conducted of pediatric patients (12-17 years) with suspected CHS presenting to one of two tertiary-care EDs; one pediatric and one pediatric/adult (combined annual pediatric census 40,550) between April 2014-March 2019. Charts were selected based on discharge diagnosis of abdominal pain or nausea/vomiting with positive cannabis urine screen, or discharge diagnosis of cannabis use, using ICD-10 codes. Patients with confirmed or likely diagnosis of CHS were identified and data including demographics, clinical history, and ED investigations/treatments were recorded by a trained research assistant. Results: 242 patients met criteria for review. 39 were identified as having a confirmed or likely diagnosis of CHS (mean age 16.2, SD 0.85 years with 64% female). 87% were triaged as either CTAS-2 or CTAS-3. 80% of patients had cannabis use frequency/duration documented. Of these, 89% reported at least daily use, the mean consumption was 1.30g/day (SD 1.13g/day), and all reported ≥6 months of heavy use. 69% of patients had at least one psychiatric comorbidity. When presenting to the ED, all had vomiting, 81% had nausea, 81% had abdominal pain, and 30% reported weight loss. Investigations done included venous blood gas (30%), pregnancy test in females (84%), liver enzymes (57%), pelvic or abdominal ultrasound (19%), abdominal X-ray (19%), and CT head (5%). 89% of patients received treatment in the ED with 81% receiving anti-emetics, 68% receiving intravenous (IV) fluids, and 22% receiving analgesics. Normal saline was the most used IV fluid (80%) and ondansetron was the most used anti-emetic (90%). Cannabis was suspected to account for symptoms in 74%, with 31% of these given the formal diagnosis of CHS. 62% of patients had another visit to the ED within 30 days (prior to or post sentinel visit), 59% of these for similar symptoms. Conclusion: This study of pediatric CHS reveals unique findings including a preponderance of female patients, a majority that consume cannabis daily, and weight loss reported in nearly one third. Many received extensive workups and most had multiple clustered visits to the ED.
In recent years, men who have sex with men (MSM) constitute a major group of HIV transmission in China. High primary drug-resistance (PDR) rate in MSM also represents a serious challenge for the Chinese antiretroviral therapy (ART) program. To assess the efficiency of ART in controlling HIV/AIDS infection among MSM, we developed a compartmental model for the annually reported HIV/AIDS MSM from 2007 to 2019 in the Zhejiang Province of China. R0 was 2.3946 (95% CI (2.2961–2.4881)). We predict that 90% of diagnosed HIV/AIDS individuals will have received treatment till 2020, while the proportion of the diagnosed remains as low as 40%. Even when the proportion of the diagnosed reaches 90%, R0 is still larger than the level of AIDS epidemic elimination. ART can effectively control the spread of HIV, even in the presence of drug resistance. The 90-90-90 strategy alone may not eliminate the HIV epidemic in Chinese MSM. Behavioural and biologic interventions are the most effective interventions to control the HIV/AIDS epidemic among MSM.
Perovskite solar cells are at the edge of commercial success. Device efficiency records are being broken at a regular pace, while stability and optimization are progressing rapidly. The first commercial products could reach the market within a year. MRS Bulletin presents coverage of the most recent impactful advances in the burgeoning field of perovskite research.
Patients with severe mental disorders in low-resource settings have limited access to services, resulting in overwhelming caregiving burden for families. In extreme cases, this has led to the long-term restraining of patients in their homes. China underwent a nationwide initiative to unlock patients and provide continued treatment. This study aims to quantify household economic burden in families after unlocking and treatment, and to identify factors associated with increased burden due to schizophrenia.
A total of 264 subjects were enrolled from three geographically diverse provinces in 2012. Subjects were patients with schizophrenia who were previously put under restraints and had participated in the ‘unlocking and treatment’ intervention. The primary outcome was the current household economic burden, obtained from past year financial information collected through on-site interview. Patient disease characteristics, treatment, outcomes and family caregiving burden were collected as well. Univariate and multivariate linear regression were used to construct risk factor models for indirect economic burden.
After participating in the intervention, 85% of patients continued to receive mental health services, 70% used medication as prescribed and 80% were never relocked. Family members reported significantly decreased caregiving burden after receiving the intervention. Mean direct and indirect household economic burdens were CNY963 (US$31.7) and CNY11 724 (US$1670) per year, respectively, while family total income was on average CNY12 108 (US$1913) per year. Greater disease severity and poorer patient psychosocial function at time of study were found to be independent factors related to increased indirect burden.
The ‘unlocking and treatment’ intervention has improved the lives of patients and families. Indirect burden due to disease is still a major economic issue that needs to be addressed, potentially through improving treatment and patient functioning. Our findings contribute to the unravelling and eventual elimination of chronic restraining of mentally ill patients in low-resource settings.
Understanding changes in chemistry, microstructure, and physical properties during synthesis, processing, testing, and even service is vital for materials design and performance. Compared to traditional postmortem material characterization tools, in situ crystallographic characterization can provide considerable data and information on evolution of chemistry, dislocations, twinning, texture, and strains when a material is under external stimuli. Neutrons especially are able to probe material bulk properties and behaviors in extreme environments, thanks to their deep penetrating power and unique sensitivity to differentiate elements from lightweight to transition-metal atoms. In this article, we introduce and describe a diffractometer named VULCAN, which is located at Oak Ridge National Laboratory. This represents a powerful tool to understand materials properties and behaviors under complex environments, in particular, at high temperatures.
Magnesium alloys usually lack “operative deformation slip mechanisms” because of their hexagonal close-packed structure. Therefore, the mechanical behavior of magnesium alloys at different temperatures is dictated by other deformation mechanisms such as twinning, detwinning, secondary twinning, or dynamic recrystallization (DRX). Twinning and DRX can affect the development of grain size and orientation distribution, as well as the deformation behavior of magnesium alloys. The current understanding of the mechanisms and mechanics of these different deformation modes and their implementation in crystal plasticity-based modeling are highlighted in this article. Future directions in the development of constitutive models are also discussed.
Little is known about long-term employment outcomes for patients with first-episode schizophrenia-spectrum (FES) disorders who received early intervention services.
We compared the 10-year employment trajectory of patients with FES who received early intervention services with those who received standard care. Factors differentiating the employment trajectories were explored.
Patients with FES (N = 145) who received early intervention services in Hong Kong between 1 July 2001 and 30 June 2002 were matched with those who entered standard care 1 year previously. We used hierarchical clustering analysis to explore the 10-year employment clusters for both groups. We used the mixed model test to compare cluster memberships and piecewise regression analysis to compare the employment trajectories of the two groups.
There were significantly more patients who received the early intervention service in the good employment cluster (early intervention: N = 98 [67.6%]; standard care: N = 76 [52.4%]; P = 0.009). In the poor employment cluster, there was a significant difference in the longitudinal pattern between early intervention and standard care for years 1–5 (P < 0.0001). The number of relapses during the first 3 years, months of full-time employment during the first year and years of education were significant in differentiating the clusters of the early intervention group.
Results suggest there was an overall long-term benefit of early intervention services on employment. However, the benefit was not sustained for all patients. Personalisation of the duration of the early intervention service with a focus on relapse prevention and early vocational reintegration should be considered for service enhancement.
Diagnosis, treatment, and prevention of vector-borne disease (VBD) in pets is one cornerstone of companion animal practices. Veterinarians are facing new challenges associated with the emergence, reemergence, and rising incidence of VBD, including heartworm disease, Lyme disease, anaplasmosis, and ehrlichiosis. Increases in the observed prevalence of these diseases have been attributed to a multitude of factors, including diagnostic tests with improved sensitivity, expanded annual testing practices, climatologic and ecological changes enhancing vector survival and expansion, emergence or recognition of novel pathogens, and increased movement of pets as travel companions. Veterinarians have the additional responsibility of providing information about zoonotic pathogen transmission from pets, especially to vulnerable human populations: the immunocompromised, children, and the elderly. Hindering efforts to protect pets and people is the dynamic and ever-changing nature of VBD prevalence and distribution. To address this deficit in understanding, the Companion Animal Parasite Council (CAPC) began efforts to annually forecast VBD prevalence in 2011. These forecasts provide veterinarians and pet owners with expected disease prevalence in advance of potential changes. This review summarizes the fidelity of VBD forecasts and illustrates the practical use of CAPC pathogen prevalence maps and forecast data in the practice of veterinary medicine and client education.
Introduction: With a shift towards competency-based medical education, it is crucial to not only emphasize learner abilities such as clinical skills but also leadership in the conduct of research. Though the Royal College of Physicians and Surgeons of Canada's (RCPSC) training objectives for Emergency Medicine (EM) residents state that the specialist physician be able to describe the principles of research, the research methodology curriculum across EM training programs in Canada is likely variable. The primary goal of this study was to describe the variability of research methodology teaching among RCPSC-EM residency programs. Methods: An electronic survey was distributed to English-speaking RCPSC-EM program directors (PDs) and EM residents. The survey investigated residents' and PDs’ thoughts on the adequacy of their local curriculum and asked them to quantify their research methodology teaching. The primary outcome was the frequency and content of current research methodology and research ethics teaching as well as a description of scholarly project requirements of EM residency programs across Canada. The data was presented with simple descriptive statistics. Results: 79 EM residents and 7 PDs responded (response rate 22.3% and 58.3%, respectively). All 7 PDs indicate having a research methodology curriculum while 71.6% of residents are aware of this curriculum. Only 57.1% of PDs report having formal assessments. Most programs (71.4%) teach via small groups while 28.6% of programs use large group sessions. Residents identify teaching as led by research staff (68.9%), staff physicians (60%), and EM researchers (57.8%), while only 17.8% use outside educators. Students noted various modalities of curriculum feedback such as online surveys, weekly forms, and verbal feedback. Regarding the strength of the curricula, 85.7% of PDs believed their curriculum prepares residents for board exams, while only 62.2% of residents felt similarly. When asked about using a standard web-based curriculum module if available, 60.5% of residents responded in favour. Conclusion: This study demonstrates that EM residency programs across Canada vary with respect to research methodology curriculum and discrepancies exist between residents’ and program directors’ perceptions of the curriculum. Given the lack of a standardized research methodology curriculum for these residency programs, there is an opportunity for curriculum development to improve training in research methodology.
Introduction: Cannabis Hyperemesis Syndrome (CHS) is a new and poorly understood phenomenon with a subset of patients presenting to emergency departments (ED) for symptomatic control of their refractory nausea and vomiting. Curently, there is a lack of agreement and considerable practice variability on initial treatment modalities for CHS. The objective of this study was to describe the treatment modalities for patients presenting to ED with cannabis-related sequelae. Methods: This was a health records review of patients ≥18 years presenting to one of two tertiary care EDs (annual census: 150,000) with a discharge diagnosis including cannabis use with one of abdominal pain or nausea/vomiting using ICD-10 codes. Trained research personnel collected data from medical records including demographics, clinical history, results of investigations, and utilization of treatment options within the ED. Descriptive statistics are presented where appropriate. Results: From April 2014 to June 2016, 203 unique ED patients had a discharge diagnosis including cannabis use with abdominal pain or nausea/vomiting. Sixty-nine (33.4%) received any treatment during their visit with 28 (40.6%) receiving IV fluids, of which 24 (85.7%) received normal saline. Anti-emetics were used in 21 (30.4%) patients with ondansetron being the first-line agent in 11 (52.4%) patients followed by dimenhydrinate in 6 (28.6%) and haloperidol in 2 (9.5%) cases. Six patients required two doses of anti-emetics, favouring ondansetron in 3 cases followed by haloperidol, dimenhydrinate, and metoclopramide each used once. Thirteen (19%) patients required analgesia, with the first-line preference being non-opioid medications in 11 versus opioids in 2 cases. Seven patients required multiple modes of analgesia, favouring opioid medications in 4 patients. Twenty-eight (40.6%) patients required anxiolytics with lorazepam being used primarily in 16 (57.1%) patients followed by lorazepam/haloperidol in 5 (17.9%) cases. Conclusion: This ED-based study demonstrates variability of practice patterns for symptomatic treatment of cannabis related ED presentations. Despite knowledge of haloperidol being useful in patients with suspected CHS, physicians opted for ondansetron as first line anti-emetics. Future research should focus on studying various treatment modalities of patients with suspected CHS in the ED to optimize symptomatic treatment.
Introduction: Cannabis Hyperemesis Syndrome (CHS) is a poorly understood phenomenon with a subset of patients presenting to the emergency department (ED) for symptomatic control of refractory nausea and vomiting. As legalization of marijuana commenced on October 2018, it is important to recognize the presentation of patients related to marijuana consumption. The objective of this study was to describe demographic and ED visit data of patients presenting to the ED with cannabis-related sequelae. Methods: This was a health records review of patients ≥18 years presenting to one of two tertiary care EDs (annual census 150,000 visits) with a discharge diagnosis including cannabis use with one of abdominal pain or nausea/vomiting using ICD-10 codes. Trained research personnel collected data from medical records including demographics, clinical history, results of investigations within the ED. Descriptive statistics including means and standard deviations are presented where appropriate. Results: From April 2014 to June 2016, 203 unique ED patients had a discharge diagnosis including cannabis use with abdominal pain or nausea/vomiting. Mean (SD) age was 30 (13.04) years and 120 (59.1%) were male. Patients presented to the ED independently 84 (41.4%), via EMS with 104 (51.23%) and 15 (7.39%) by police. The majority of patients were triaged as CTAS-2 in 27 (33%) and CTAS-3 in 106 (52.2%) of all cases. Of patients disclosing their method of consumption, 31 (15.3%) had used combustion methods and 30 (14.8%) had edible marijuana. Mean (SD) serum potassium was 3.71 (0.48) mmol/l. 162 (79.8%) were discharged home and 9 (4.4%) were given follow up (all psychiatric). Twenty-nine (14.3%) were admitted to hospital with 28 (13.8%) admitted to psychiatry and 1 (0.5%) admitted to medicine. Conclusion: This ED-based retrospective chart review reports a description of cannabis-related presentations to the ED. Clinicians should be aware of CHS in patients presenting to the ED, especially as Canada enters the era of legalization. Future research should focus on the impact of federal legalization of marijuana on ED utilization for CHS-related presentations.