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The cost-effectiveness of endovascular therapy (EVT) compared to tissue plasminogen activator (tPA) alone for acute ischemic stroke (AIS) has been established in the literature. However, decision-makers still face challenges of how to best deliver EVT in a timely manner to maximize patient outcomes while minimizing the burden to the healthcare system, given that AIS has time-dependent treatment outcomes. The objective of this presentation is to report an optimization approach for improving health system value and outcomes for patients with AIS who are eligible for EVT in Alberta.
An economic model was developed to compare combinations of “mothership” (transport directly to a comprehensive stroke center [CSC] to receive tPA and EVT) and “drip-and-ship” (transport to a primary stroke centre to receive tPA, followed by transport to a CSC to receive EVT) methods across Alberta. The model considered geographical variation and searched for the best delivery methods through a pairwise comparison of all possible strategies. The controlled variables including in the model were population densities, disease epidemiology, time/distance to hospitals, available medical services, treatment eligibility and efficacy, and costs. Patient outcomes were measured by functional independence. The model defined optimal strategies by identifying the transport methods that produced the highest probability of improved health outcomes at the lowest cost.
The analysis produced an optimization map showing optimal strategies for EVT delivery. The lifetime cost (standard deviation [SD]) per patient and likelihood (SD) of good outcomes was CAD 291,769 (CAD 11,576) [USD 226,207 (USD 8,975)] and 41.82 percent (0.013) when considering optimal clinical outcomes, and CAD 287,725 (CAD 4,141) [USD 223,097 (USD 3,211)] and 41.67 percent (0.016) when considering optimal economic efficiency.
Our model reduces the gap that exists between health technology implementation and cost-effectiveness analysis; namely, neither fully addresses relative efficiency driven by geographical variation, which may misrepresent system value in local settings. Implementation strategies generated in our model capture full values in terms of patient outcomes and costs.
Alteplase is an effective treatment for ischaemic stroke patients, and it is widely available at all primary stroke centres. The effectiveness of alteplase is highly time-dependent. Large tertiary centres have reported significant improvements in their door-to-needle (DTN) times. However, these same improvements have not been reported at community hospitals.
Red Deer Regional Hospital Centre (RDRHC) is a community hospital of 370 beds that serves approximately 150,000 people in their acute stroke catchment area. The RDRHC participated in a provincial DTN improvement initiative, and implemented a streamlined algorithm for the treatment of stroke patients. During this intervention period, they implemented the following changes: early alert of an incoming acute stroke patient to the neurologist and care team, meeting the patient immediately upon arrival, parallel work processes, keeping the patient on the Emergency Medical Service stretcher to the CT scanner, and administering alteplase in the imaging area. Door-to-needle data were collected from July 2007 to December 2017.
A total of 289 patients were treated from July 2007 to December 2017. In the pre-intervention period, 165 patients received alteplase and the median DTN time was 77 minutes [interquartile range (IQR): 60–103 minutes]; in the post-intervention period, 104 patients received alteplase and the median DTN time was 30 minutes (IQR: 22–42 minutes) (p < 0.001). The annual number of patients that received alteplase increased from 9 to 29 in the pre-intervention period to annual numbers of 41 to 63 patients in the post-intervention period.
Community hospitals staffed with community neurologists can achieve median DTN times of 30 minutes or less.
The impact of losing a limb in military service extends well beyond initial recovery and rehabilitation, with long-term consequences and challenges requiring health-care commitments across the lifecourse. This paper presents a systematic review of the current state of knowledge regarding the long-term impact of ageing and limb-loss in military veterans. Key databases were systematically searched including: ASSIA, CINAHL, Cochrane Library, Medline, Web of Science, PsycArticles/PsychInfo, ProQuest Psychology and ProQuest Sociology Journals, and SPORTSDiscus. Empirical studies which focused on the long-term impact of limb-loss and/or health-care requirements in veterans were included. The search process revealed 30 papers relevant for inclusion. These papers focused broadly on four themes: (a) long-term health outcomes, prosthetics use and quality of life; (b) long-term psycho-social adaptation and coping with limb-loss; (c) disability and identity; and (d) estimating the long-term costs of care and prosthetic provision. Findings present a compelling case for ensuring the long-term care needs and costs of rehabilitation for older limbless veterans are met. A dearth of information on the lived experience of limb-loss and the needs of veterans’ families calls for further research to address these important issues.
In this brief report, computed tomography perfusion (CTP) thresholds predicting follow-up infarction in patients presenting <3 hours from stroke onset and achieving ultra-early reperfusion (<45 minutes from CTP) are reported. CTP thresholds that predict follow-up infarction vary based on time to reperfusion: Tmax >20 to 23 seconds and cerebral blood flow <5 to 7 ml/min−1/(100 g)−1 or relative cerebral blood flow <0.14 to 0.20 optimally predicted the final infarct. These thresholds are stricter than published thresholds.
Silent pulmonary embolism (PE) may be associated with acute ischemic stroke (AIS). We identified 10 patients from 3,132 unique patients (3,431 CT scans). We retrospectively examined CT angiogram of patients with AIS to determine the frequency of concurrent PE in AIS. The period prevalence of PE was 0.32. Seven patients had concurrent PE, whereas three had PE diagnosed 2 days after their AIS presentation. We suspected paradoxical embolism via patent foramen ovale as the cause of stroke in three patients and thrombophilia in four patients. Seven patients had poor outcome including four deaths. CT angiogram stroke protocol images from aortic arch to vertex allows visualization of upper pulmonary arteries and PE detection in AIS.
Vulnerability of satellite-based navigation signals to intentional and unintentional interference calls for a high-level overview of Global Navigation Satellite System (GNSS) threats occurring globally to understand the magnitude and evolution of the problem. Therefore, a mechanism needs to be developed whereby disparate monitoring systems will be capable of contributing to a common entity of basic information about the threat scenarios they experience. This paper begins with a literature survey of 37 state-of-the-art GNSS threat monitoring systems, which have been analysed based on their respective operational features - constellations monitored and whether they possess the capability to perform interference-type classification, spoofing detection, and interference localisation. Also described is a comparative analysis of four GNSS threat reporting formats in use today. Based on these studies, the paper describes the Horizon2020 Standardisation of GNSS Threat Reporting and Receiver Testing through International Knowledge Exchange, Experimentation and Exploitation (STRIKE3) proposed integrated threat monitoring demonstration system and related standardised threat reporting message, to enable a high-level overview of the prevailing international GNSS threat scenarios and its evolution over time.
We examine the role of status quo bias in the ballot wording of social issues that affect the rights of minority groups. We test the salience of this framing bias by conducting an experiment that randomly assigns different ballot wordings for five policies across survey respondents. We find that status quo bias changes the percent of individuals who vote for the ballot measure by 5–8 percentage points with the least informed individuals being the most affected by status quo bias.
Early-life institutional deprivation produces disinhibited social engagement (DSE). Portrayed as a childhood condition, little is known about the persistence of DSE-type behaviours into, presentation during, and their impact on, functioning in adulthood.
We examine these issues in the young adult follow-up of the English and Romanian Adoptees study.
A total of 122 of the original 165 Romanian adoptees who had spent up to 43 months as children in Ceauşescu's Romanian orphanages and 42 UK adoptees were assessed for DSE behaviours, neurodevelopmental and mental health problems, and impairment between ages 2 and 25 years.
Young adult DSE behaviour was strongly associated with early childhood deprivation, with a sixfold increase for those who spent more than 6 months in institutions. However, although DSE overlapped with autism spectrum disorder and attention-deficit hyperactivity disorder symptoms it was not, in itself, related to broader patterns of mental health problems or impairments in daily functioning in young adulthood.
DSE behaviour remained a prominent, but largely clinically benign, young adult feature of some adoptees who experienced early deprivation.
Adequate nutrition is critical for optimal growth and development. However, young children may be at risk of nutrient deficiencies when transitioning to weaning foods for a variety of reasons. Supplementation with fortified milk may provide potentially lacking essential nutrients, but effects on growth and nutritional status are yet to be established.
Five databases were searched for randomised controlled trials using fortified milk against control milk in young children. Outcomes were growth, body composition and/or biochemical markers. Pooled differences in means were calculated for continuous outcomes and odds ratios for binary outcomes.
Randomised controlled trials set in any country.
Otherwise healthy children aged 6–47 months.
Fifteen articles met the eligibility criteria. Fortification varied from Fe, Zn, vitamins, essential fatty acids, to pre- and/or probiotics. Frequently reported outcomes were weight, height and Fe status. Studies varied in geographical location, sample size and duration. Fortified milk had minimal effects on weight gain (mean difference=0·17 kg; 95 % CI 0·02, 0·31 kg) compared with control milk. The risk of anaemia was reduced in fortified milk groups (OR=0·32; 95 % CI 0·15, 0·66) compared with control groups. There were no significant effects on height gain, changes in body composition or Hb concentration.
Fortified milk is an effective source of complementary nutrition to supplement children in need when consumed in appropriate amounts in addition to a normal diet. Due to compositional differences, further research on fortified milk is warranted before making global recommendations on benefits for growth and nutritional outcomes in young children.
Background: Stroke patients of lower socioeconomic status have worse outcomes. It remains poorly understood whether this is due to illness severity or personal or health system barriers. We explored the experiences of stroke patients with financial barriers in a qualitative descriptive pilot study, seeking to capture perceived challenges that interfere with their poststroke health and recovery. Methods: We interviewed six adults with a history of stroke and financial barriers in Alberta, Canada, inquiring about their: (1) experiences after stroke; (2) experience of financial barriers; (3) perceived reasons for financial barriers; (4) health consequences of financial barriers; and (5) mechanisms for coping with financial barriers. Two reviewers analyzed data using inductive thematic analysis. Results: The participants developed new or worsened financial circumstances as a consequence of stroke-related disability. Poststroke impairments and financial barriers took a toll on their mental health. They struggled to access several aspects of long-term poststroke care, including allied health professional services, medications, and proper nutrition. They described opportunity costs and tradeoffs when accessing health services. In several cases, they were unaware of health resources available to them and were hesitant to disclose their struggles to their physicians and even their families. Conclusion: Some patients with financial barriers perceive challenges to accessing various aspects of poststroke care. They may have inadequate knowledge of resources available to them and may not disclose their concerns to their health care team. This suggests that providers themselves might consider asking stroke patients about financial barriers to optimize their long-term poststroke care.
The aim of this study was to describe previously unrecognised or under-recognised adverse events associated with Melody® valve implantation.
In rare diseases and conditions, it is typically not feasible to conduct large-scale safety trials before drug or device approval. Therefore, post-market surveillance mechanisms are necessary to detect rare but potentially serious adverse events.
We reviewed the United States Food and Drug Administration’s Manufacturer and User Facility Device Experience (MAUDE) database and conducted a structured literature review to evaluate adverse events associated with on- and off-label Melody® valve implantation. Adverse events were compared with those described in the prospective Investigational Device Exemption and Post-Market Approval Melody® transcatheter pulmonary valve trials.
We identified 631 adverse events associated with “on-label” Melody® valve implants and 84 adverse events associated with “off-label” implants. The most frequent “on-label” adverse events were similar to those described in the prospective trials including stent fracture (n=210) and endocarditis (n=104). Previously unrecognised or under-recognised adverse events included stent fragment embolisation (n=5), device erosion (n=4), immediate post-implant severe valvar insufficiency (n=2), and late coronary compression (n=2 cases at 5 days and 3 months after implantation). Under-recognised adverse events associated with off-label implantation included early valve failure due to insufficiency when implanted in the tricuspid position (n=7) and embolisation with percutaneous implantation in the mitral position (n=5).
Post-market passive surveillance does not demonstrate a high frequency of previously unrecognised serious adverse events with “on-label” Melody® valve implantation. Further study is needed to evaluate safety of “off-label” uses.
Background: Stroke is often preceded by transient symptoms. Although global stroke rates have been shown to be declining, previous studies have reported inconsistent temporal trends of transient ischemic attacks (TIA). The objective of the current study is to report the temporal trends of TIA admissions and outcomes in Canada over the last 11 years. Methods: We conducted a complete population cohort study using a national administrative database to study the temporal trend of age- and sex-adjusted TIA admission rates in Canada from 2003 to 2013. We also determined the rates of TIA and stroke diagnoses in the emergency department in the province of Ontario during the same period. We used multivariable analyses to study discharge location after acute hospitalization as well as 90-day stroke and/or TIA readmission rates. Results: Of 425,799 admissions to an acute care hospital for all stroke and TIA, 71,443 (16.8%) were TIA. The age- and sex-standardized rates of TIA admission decreased significantly during the study period from 30.0 to 20.6 per 100,000 (p<0.0001). In Ontario, decreasing TIA admissions is mirrored by decreasing rates of TIA directly discharged from the emergency department (55.1 to 46.8 per 100,000, p = 0.002). The odds of 90-day readmission rates for stroke or TIA are also decreasing (adjusted odds ratio, 0.97; 95% confidence interval, 0.96-0.99). Conclusions: We show that TIA admission rates have declined in the past 11 years in Canada, reflecting improved vascular risk reduction and stroke care. Future studies to confirm our findings on improved stroke or TIA recurrence rates are necessary.
Background: Interhospital transfer is an important but resource-intensive pattern of care. The use for stroke patients is highly dependent upon health system structure. We examined the impact of hospital transfers for stroke care in Canada. Methods: We analyzed hospital administrative data within the Canadian Institute for Health Information (CIHI) Database for the 3 fiscal years 2011/12, 2012/13 and 2013/14. Patients with clinical stroke syndrome (ischemic or hemorrhagic) were identified using International Classification of Diseases. Stroke centers were defined by Heart & Stroke Foundation of Canada stroke report. Results: During the 3-year period,397 patients in Canada (excluding Quebec) were admitted to hospital for clinical stroke syndrome. Median age was 75 (interquartile range [IQR] 64–84) years; 50.6 % were male. Less than 5% (n=4030) of patients were transferred. Patients transferred to stroke centers were younger (p<0.001) and had shorter median length of stay (p<0.001). The highest probability of discharge home was associated with sole care at stroke center (43.8%). Transfer to stroke center from community hospital had the highest probability for discharge to rehabilitation facility (25%) and lowest to either long-term (2.1%) or complex community care (2.0%). Transferred patients had lower mortality at discharge. Conclusion: Younger patients were transferred more frequently to stroke centers; older patients were more likely treated in community hospitals. Sole stroke center care was associated with high discharge rate to home; transfer to a stroke center was associated with high discharge rate to rehabilitation and lower mortality rates.
The two-point theory of homogeneous isotropic turbulence is extended to source terms appearing in the equations for higher-order structure functions. For this, transport equations for these source terms are derived. We focus on the trace of the resulting equations, which is of particular interest because it is invariant and therefore independent of the coordinate system. In the trace of the even-order source term equation, we discover the higher-order moments of the dissipation distribution, and the individual even-order source term equations contain the higher-order moments of the longitudinal, transverse and mixed dissipation distribution functions. This shows for the first time that dissipation fluctuations, on which most of the phenomenological intermittency models are based, are contained in the Navier–Stokes equations. Noticeably, we also find the volume-averaged dissipation
used by Kolmogorov (J. Fluid Mech., vol. 13, 1962, pp. 82–85) in the resulting system of equations, because it is related to dissipation correlations.
The aim of the study was to evaluate the trends in respiratory syncytial virus-related hospitalisations and associated outcomes in children with haemodynamically significant heart disease in the United States of America.
The Kids’ Inpatient Databases (1997–2012) were used to estimate the incidence of respiratory syncytial virus hospitalisation among children ⩽24 months with or without haemodynamically significant heart disease. Weighted multivariable logistic regression and chi-square tests were used to evaluate the trends over time and factors associated with hospitalisation, comparing eras before and after publication of the 2003 American Academy of Pediatrics palivizumab immunoprophylaxis guidelines. Secondary outcomes included in-hospital mortality, morbidity, length of stay, and cost.
Overall, 549,265 respiratory syncytial virus-related hospitalisations were evaluated, including 2518 (0.5%) in children with haemodynamically significant heart disease. The incidence of respiratory syncytial virus hospitalisation in children with haemodynamically significant heart disease decreased by 36% when comparing pre- and post-palivizumab guideline eras versus an 8% decline in children without haemodynamically significant heart disease (p<0.001). Children with haemodynamically significant heart disease had higher rates of respiratory syncytial virus-associated mortality (4.9 versus 0.1%, p<0.001) and morbidity (31.5 versus 3.5%, p<0.001) and longer hospital length of stay (17.9 versus 3.9 days, p<0.001) compared with children without haemodynamically significant heart disease. The mean cost of respiratory syncytial virus hospitalisation in 2009 was $58,166 (95% CI:$46,017, $70,315).
These data provide stakeholders with a means to evaluate the cost–utility of various immunoprophylaxis strategies.
Although intravenous thrombolysis increases the probability of a good functional outcome in carefully selected patients with acute ischemic stroke, a substantial proportion of patients who receive thrombolysis do not have a good outcome. Several recent trials of mechanical thrombectomy appear to indicate that this treatment may be superior to thrombolysis. We therefore conducted a systematic review and meta-analysis to evaluate the clinical effectiveness and safety of new-generation mechanical thrombectomy devices with intravenous thrombolysis (if eligible) compared with intravenous thrombolysis (if eligible) in patients with acute ischemic stroke caused by a proximal intracranial occlusion. We systematically searched seven databases for randomized controlled trials published between January 2005 and March 2015 comparing stent retrievers or thromboaspiration devices with best medical therapy (with or without intravenous thrombolysis) in adults with acute ischemic stroke. We assessed risk of bias and overall quality of the included trials. We combined the data using a fixed or random effects meta-analysis, where appropriate. We identified 1579 studies; of these, we evaluated 122 full-text papers and included five randomized control trials (n=1287). Compared with patients treated medically, patients who received mechanical thrombectomy were more likely to be functionally independent as measured by a modified Rankin score of 0-2 (odds ratio, 2.39; 95% confidence interval, 1.88-3.04; I2=0%). This finding was robust to subgroup analysis. Mortality and symptomatic intracerebral hemorrhage were not significantly different between the two groups. Mechanical thrombectomy significantly improves functional independence in appropriately selected patients with acute ischemic stroke.