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An estimated 15% of all patients admitted to stroke rehabilitation units experience a brainstem stroke. Two case studies are presented to illustrate some of the difficulties encountered in the rehabilitation of these individuals. Unlike hemispheric stroke, the characteristic consequences of brainstem stroke include ataxia, dysarthria, and diplopia. Additionally, individuals with brainstem stroke may suffer from severe dysphagia and may require enteral feedings. Unlike the rehabilitation of patients with hemispheric stroke, where there is an impressive and relatively comprehensive research literature, there has been surprisingly little research published on the rehabilitation of patients with brainstem stroke despite the fact they represent a significant number of patients admitted to stroke rehabilitation units. [ABSTRACT FROM AUTHOR]

Quantum computing crucially relies on the ability to efficiently characterize the quantum states output by quantum hardware. Conventional methods which probe these states through direct measurements and classically computed correlations become computationally expensive when increasing the system size. Quantum neural networks tailored to recognize specific features of quantum states by combining unitary operations, measurements and feedforward promise to require fewer measurements and to tolerate errors. Here, we realize a quantum convolutional neural network (QCNN) on a 7-qubit superconducting quantum processor to identify symmetry-protected topological (SPT) phases of a spin model characterized by a non-zero string order parameter. We benchmark the performance of the QCNN based on approximate ground states of a family of cluster-Ising Hamiltonians which we prepare using a hardware-efficient, low-depth state preparation circuit. We find that, despite being composed of finite-fidelity gates itself, the QCNN recognizes the topological phase with higher fidelity than direct measurements of the string order parameter for the prepared states., (© 2022. The Author(s).)

Quantum computers hold the promise of solving computational problems that are intractable using conventional methods 1 . For fault-tolerant operation, quantum computers must correct errors occurring owing to unavoidable decoherence and limited control accuracy 2 . Here we demonstrate quantum error correction using the surface code, which is known for its exceptionally high tolerance to errors 3-6 . Using 17 physical qubits in a superconducting circuit, we encode quantum information in a distance-three logical qubit, building on recent distance-two error-detection experiments 7-9 . In an error-correction cycle taking only 1.1 μs, we demonstrate the preservation of four cardinal states of the logical qubit. Repeatedly executing the cycle, we measure and decode both bit-flip and phase-flip error syndromes using a minimum-weight perfect-matching algorithm in an error-model-free approach and apply corrections in post-processing. We find a low logical error probability of 3% per cycle when rejecting experimental runs in which leakage is detected. The measured characteristics of our device agree well with a numerical model. Our demonstration of repeated, fast and high-performance quantum error-correction cycles, together with recent advances in ion traps 10 , support our understanding that fault-tolerant quantum computation will be practically realizable., (© 2022. The Author(s), under exclusive licence to Springer Nature Limited.)

Objectives: In recent years, Lean manufacturing principles have been applied to health care quality improvement efforts to improve wait times. In Ontario, an emergency department (ED) process improvement program based on Lean principles was introduced by the Ministry of Health and Long-Term Care as part of a strategy to reduce ED length of stay (LOS) and to improve patient flow. This article aims to describe the hospital-based teams' experiences during the ED process improvement program implementation and the teams' perceptions of the key factors that influenced the program's success or failure., Methods: A qualitative evaluation was conducted based on semistructured interviews with hospital implementation team members, such as team leads, medical leads, and executive sponsors, at 10 purposively selected hospitals in Ontario, Canada. Sites were selected based, in part, on their changes in median ED LOS following the implementation period. A thematic framework approach as used for interviews, and a standard thematic coding framework was developed., Results: Twenty-four interviews were coded and analyzed. The results are organized according to participants' experience and are grouped into four themes that were identified as significantly affecting the implementation experience: local contextual factors, relationship between improvement team and support players, staff engagement, and success and sustainability. The results demonstrate the importance of the context of implementation, establishing strong relationships and communication strategies, and preparing for implementation and sustainability prior to the start of the project., Conclusions: Several key factors were identified as important to the success of the program, such as preparing for implementation, ensuring strong executive support, creation of implementation teams based on the tasks and outcomes of the initiative, and using multiple communication strategies throughout the implementation process. Explicit incorporation of these factors into the development and implementation of future similar interventions in health care settings could be useful., (© 2015 by the Society for Academic Emergency Medicine.)

Objectives: To examine the risk of bowel obstruction in older adults during treatment with extended-release nifedipine compared with patients treated with amlodipine., Design: Retrospective cohort study using multiple linked healthcare databases., Setting: Ontario, Canada from 1 April 1997 to 31 December 2010., Participants: We identified patients aged 66 years and older who started treatment with Adalat XL, an extended-release nifedipine product employing a tablet delivery system associated with mechanical bowel obstruction. For comparison, we studied patients receiving amlodipine, a long-acting calcium channel blocker that does not utilise the same delivery system and has not been implicated as a cause of bowel obstruction. Propensity score matching was used to ensure similarity of patients receiving the two drugs., Primary Outcome Measure: HR for the association between extended-release nifedipine relative to amlodipine and hospitalisation for bowel obstruction during therapy., Results: Over the 13-year study period, we identified 103 657 patients treated with extended-release nifedipine and 204 733 patients treated with amlodipine. In these two groups, 591 (0.6%) and 1185 (0.6%) of patients were hospitalised for bowel obstruction, respectively. We found no difference in the risk of bowel obstruction among patients treated with extended-release nifedipine compared with amlodipine (HR 1.09, 95% CI 0.96 to 1.24)., Conclusions: Bowel obstruction during treatment with extended-release nidefipine is rare, and the risk is not appreciably greater than that during treatment with amlodipine., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.)

Background: Recent evidence suggests that proton pump inhibitors (PPIs) might be linked with adverse cardiac events, but a causal relationship is unproven., Methods: We applied the self-matched case series method to two studies using population-based health care data from Ontario, Canada between 1996 and 2008. The first included subjects aged 66 years or older hospitalized for acute myocardial infarction within 12 weeks following initiation of PPI, while the second included subjects hospitalized for heart failure. In both studies we designated the primary risk interval as the initial 4 weeks of therapy and the control interval as the final 4 weeks. To test the specificity of our findings we examined use of histamine H2 receptor antagonists and benzodiazepines, drugs with no plausible causal link to adverse cardiac events., Results: During the 13-year study period, we identified 5550 hospital admissions for acute myocardial infarction and 6003 admissions for heart failure within 12 weeks of commencing PPI therapy. In the main analyses, we found that initiation of a PPI was associated with a higher risk of acute myocardial infarction (odds ratio 1.8; 95% confidence interval 1.7 to 1.9) and heart failure (odds ratio 1.8; 95% confidence interval 1.7 to 1.9). However, secondary analyses revealed similar risk estimates histamine H2 receptor antagonists and benzodiazepines, drugs with no known or suspected association with adverse cardiac events., Conclusion: PPIs are associated with a short-term risk of adverse cardiac events, but similar associations are seen with other drugs exhibiting no known cardiac toxicity. Collectively these observations suggest that the association between PPIs and adverse cardiac events does not represent reflect cause-and-effect.

Background: Some evidence suggests that the direct renin inhibitor aliskiren may increase the risk of severe hyperkalemia, stroke, or acute kidney injury (AKI) when prescribed with angiotensin-converting enzyme inhibitors (ACEi's) or angiotensin-receptor blockers (ARBs). The extent to which concomitant treatment increases the risk of these outcomes in routine clinical practice is unknown. We addressed this issue with the use of administrative databases., Methods: We established a cohort of Ontarians treated with an ACEi or an ARB. Within this cohort, we conducted 3 case-control studies. Cases were patients hospitalized with 1 of 3 outcomes (hyperkalemia, AKI, or stroke). In each analysis, we identified up to 5 matched control subjects for each case. Conditional logistic regression was used to examine the association between hospitalization for each outcome and the use of aliskiren in the preceding 60 days., Results: Among 903,346 patients aged 66 years and older treated with an ACEi or ARB during the 28-month study period, we identified 4235 hospitalized with hyperkalemia, 18,231 hospitalized with AKI, and 8283 hospitalized with stroke. After extensive multivariable adjustment, aliskiren therapy was not associated with a significant increase in the risk of hospitalization for hyperkalemia, AKI, or stroke. We found similar results in stratified analyses of patients with and without a history of chronic kidney disease, diabetes, or heart failure., Conclusions: Among community-dwelling patients aged 66 years and older receiving therapy with an ACEi or an ARB, aliskiren use was not associated with hospitalization for hyperkalemia, AKI, or stroke., (Copyright © 2013 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Background: Some evidence suggests that chlorthalidone may be superior to hydrochlorothiazide for the treatment of hypertension., Objective: To compare the effectiveness and safety of chlorthalidone and hydrochlorothiazide in older adults., Design: Propensity score-matched observational cohort study with up to 5 years of follow-up., Setting: Ontario, Canada., Patients: All individuals aged 66 years or older who were newly treated with chlorthalidone or hydrochlorothiazide and were not hospitalized for heart failure, stroke, or myocardial infarction in the prior year were eligible for inclusion. Each chlorthalidone recipient was matched to up to 2 hydrochlorothiazide recipients on the basis of age, sex, year of treatment initiation, and propensity score., Measurements: The primary outcome was a composite of death or hospitalization for heart failure, stroke, or myocardial infarction. Safety outcomes included hospitalization with hypokalemia or hyponatremia., Results: A total of 29 873 patients were studied. During follow-up, chlorthalidone recipients (n = 10 384) experienced the primary outcome at a rate of 3.2 events per 100 person-years of follow-up, and hydrochlorothiazide recipients experienced 3.4 events per 100 person-years of follow-up (adjusted hazard ratio, 0.93 [95% CI, 0.81 to 1.06]). Patients treated with chlorthalidone were more likely to be hospitalized with hypokalemia (adjusted hazard ratio, 3.06 [CI, 2.04 to 4.58]) or hyponatremia (adjusted hazard ratio, 1.68 [CI, 1.24 to 2.28]). In 9 post hoc analyses comparing patients initially prescribed 12.5, 25, or 50 mg of chlorthalidone per day with those prescribed 12.5, 25, or 50 mg of hydrochlorothiazide per day, the former were more likely to be hospitalized with hypokalemia for all 6 comparisons in which a statistically significant association was found. The results of other effectiveness and safety outcomes were also consistent with those of the main analysis., Limitation: Unmeasured differences in baseline characteristics or physician treatment approaches or an insufficiently large sample may have limited the ability to detect small differences in the comparative effectiveness of the drugs., Conclusion: As typically prescribed, chlorthalidone in older adults was not associated with fewer adverse cardiovascular events or deaths than hydrochlorothiazide. However, it was associated with a greater incidence of electrolyte abnormalities, particularly hypokalemia., Primary Funding Source: Ontario Ministry of Health and Long-Term Care.

Background: Although warfarin has been extensively studied in clinical trials, little is known about rates of hemorrhage attributable to its use in routine clinical practice. Our objective was to examine incident hemorrhagic events in a large population-based cohort of patients with atrial fibrillation who were starting treatment with warfarin., Methods: We conducted a population-based cohort study involving residents of Ontario (age ≥ 66 yr) with atrial fibrillation who started taking warfarin between Apr. 1, 1997, and Mar. 31, 2008. We defined a major hemorrhage as any visit to hospital for hemorrage. We determined crude rates of hemorrhage during warfarin treatment, overall and stratified by CHADS(2) score (congestive heart failure, hypertension, age ≥ 75 yr, diabetes mellitus and prior stroke, transient ischemic attack or thromboembolism)., Results: We included 125 195 patients with atrial fibrillation who started treatment with warfarin during the study period. Overall, the rate of hemorrhage was 3.8% (95% confidence interval [CI] 3.8%-3.9%) per person-year. The risk of major hemorrhage was highest during the first 30 days of treatment. During this period, rates of hemorrhage were 11.8% (95% CI 11.1%-12.5%) per person-year in all patients and 16.7% (95% CI 14.3%-19.4%) per person-year among patients with a CHADS(2) scores of 4 or greater. Over the 5-year follow-up, 10 840 patients (8.7%) visited the hospital for hemorrhage; of these patients, 1963 (18.1%) died in hospital or within 7 days of being discharged., Interpretation: In this large cohort of older patients with atrial fibrillation, we found that rates of hemorrhage are highest within the first 30 days of warfarin therapy. These rates are considerably higher than the rates of 1%-3% reported in randomized controlled trials of warfarin therapy. Our study provides timely estimates of warfarin-related adverse events that may be useful to clinicians, patients and policy-makers as new options for treatment become available.

Background: Numerous factors affect drug utilization including clinical trials, promotional activity, drug safety signals and funding practices. We sought to investigate the impact of cardiovascular safety concerns and public drug formulary restrictions on the use of the thiazolidinediones (TZDs): rosiglitazone and pioglitazone., Methods: We conducted a population-based cross-sectional time series analysis among more than 1.6 million older residents of Ontario, Canada using administrative healthcare claims databases from January 2000 to September 2010 to examine the impact of two events on the rate of initiation of TZDs among those aged 66 years and older: 1) the publication of a prominent meta-analysis suggesting cardiovascular harm for rosiglitazone, and 2) the introduction of prescribing restrictions for TZDs on the public formulary., Results: Incident rosiglitazone prescribing decreased significantly from 5.32 to 0.44 prescriptions per 1,000 patients in the quarter following the publication of a meta-analysis, suggesting safety concerns for rosiglitazone (p<0.01). Similarly, incident pioglitazone prescribing continued to decline from 1.89 just prior to the publication of the meta-analysis to 0.53 prescriptions per 1,000 patients just prior to the policy implementation (p<0.01). Following the implementation of formulary restrictions for TZDs in Q2 of 2009, the rate of incident prescriptions for rosiglitazone fell further, from 0.20 prescriptions per 1,000 patients in the preceding quarter to 0.03 prescriptions per 1,000 patients in the subsequent quarter (Q3 of 2009; p<0.01). The rate of prescriptions dispensed for pioglitazone also decreased from 0.53 in Q1of 2009 to 0.11 prescriptions per 1,000 patients in Q3 of 2009 (p <0.01)., Conclusion: Both the publication of clinical evidence and drug policy changes can significantly influence the utilization of the TZDs.

Objectives: To examine whether postpartum maternal prescription of codeine was associated with an increased risk of harm to newborns., Design: Population-based retrospective cohort study., Setting: Ontario, Canada, from April 1, 1998 to March 1, 2008., Participants: A total of 7804 mothers with publically-funded prescription drug coverage. Women who received a prescription for a codeine-containing product within 7 days following hospital discharge and their neonates were matched to 7804 mothers who did not receive codeine following delivery., Main Outcome Measures: The primary outcome was readmission of the neonate to hospital for any reason within 30 days. Secondary outcomes included arrival to hospital by ambulance, hospitalization for dehydration, for injury, any hospitalization involving resuscitation or assisted ventilation, and all-cause mortality., Results: We studied 7804 infants whose mothers filled a prescription for codeine shortly after delivery and 7804 whose mothers did not. In the primary analysis, infants whose mothers received codeine were no more likely to be readmitted to hospital in the subsequent 30 days than children whose mothers did not (hazard ratio 0.95, 95% confidence interval (CI) 0.81-1.11). Moreover, we found no association between maternal codeine use and the other adverse neonatal outcomes studied. A stratified analysis revealed no differential risk among infants born by Caesarean section (hazard ratio 0.86; 95% CI 0.69-1.08)., Conclusions: In this large population-based study, maternal prescription of codeine following delivery was not associated with death or hospitalization in the early neonatal period.

Aims: To determine the extent to which other opioids are prescribed to patients receiving methadone in Ontario, Canada., Design: Retrospective cohort study., Setting: Ontario, Canada from 1 April 2003 to 31 March 2010., Participants: We studied patients aged 15-64 years with publically funded drug coverage who received at least 30 days of continuous methadone maintenance therapy (MMT)., Measurements: The proportion of patients who received more than 7 days of a non-methadone opioid during MMT. A secondary analysis examined the extent to which non-methadone opioids were prescribed by physicians or dispensed by pharmacies not involved in a patient's MMT., Findings: Among 18,759 patients treated with methadone, 3456 (18.4%) received at least one prescription for non-methadone opioids of more than 7 days' duration. In this group, the median number of non-methadone opioid prescriptions dispensed per year was 11.9 (interquartile range 4.1-25.0). The most frequently prescribed opioids were codeine and oxycodone. Of the 73,520 non-methadone opioid prescriptions of more than 7 days' duration, nearly half (45.8%) originated from non-MMT prescribers and pharmacies., Conclusions: Many patients receiving methadone maintenance therapy in Ontario receive overlapping prescriptions for other opioids, often for extended periods. The associated prescribing patterns suggest that many such prescriptions may be duplicitous. The prescribing and dispensing of non-methadone opioids to patients receiving methadone maintenance therapy is likely to be observed in jurisdictions outside Ontario, Canada., (© 2011 The Authors, Addiction © 2011 Society for the Study of Addiction.)

An estimated 15% of all patients admitted to stroke rehabilitation units experience a brainstem stroke. Two case studies are presented to illustrate some of the difficulties encountered in the rehabilitation of these individuals. Unlike hemispheric stroke, the characteristic consequences of brainstem stroke include ataxia, dysarthria, and diplopia. Additionally, individuals with brainstem stroke may suffer from severe dysphagia and may require enteral feedings. Unlike the rehabilitation of patients with hemispheric stroke, where there is an impressive and relatively comprehensive research literature, there has been surprisingly little research published on the rehabilitation of patients with brainstem stroke despite the fact they represent a significant number of patients admitted to stroke rehabilitation units.

Objective: To conduct a systematic review of the rehabilitation literature of moderate to severe acquired brain injuries (ABI) from traumatic and non-traumatic causes., Methods: A review of the literature was conducted for studies looking at interventions in ABI rehabilitation. The methodological quality of each study was determined using the Downs and Black scale for randomized controlled trials (RCTs) and non-RCTs as well as the Physiotherapy Evidence Database (PEDro) scale for RCTs only., Results: Almost 14 000 references were screened from which 1312 abstracts were selected. A total of 303 articles were chosen for careful review of which 275 were found to be interventional studies but only 76 of these interventional studies were RCTs. From this, 5 levels of evidence were determined with 177 conclusions drawn; however of the 177 conclusions only 7 were supported by two or more RCTs and 41 were supported by one RCT., Conclusion: Only 28% of the interventional studies were RCTs. Over half of the 275 interventional studies were single group interventions, pointing to the need for studies of improved methodological quality into ABI rehabilitation.

Objective: The present study aimed to evaluate the effectiveness of prophylactic anticonvulsant pharmacological strategies for the prevention of seizure disorders following acquired brain injury (ABI) to provide guidance for clinical practice based on the best available evidence., Methods and Main Outcomes: A systematic review of the literature from 1980-2005 was conducted focusing on treatment interventions available for post-traumatic seizures following ABI. The evidence for the efficacy of a given intervention was ranked as strong (supported by at least two randomized controlled trials (RCTs), moderate (supported by a single RCT), or limited (supported by other types of studies in the absence of RCTs)., Results: Based on a previous meta-analysis and the findings of this review, there is strong evidence that prophylactic anticonvulsant therapy decreases the occurrence of early seizures but only within the first week post-injury. Moreover, the evidence indicates that prophylactic anticonvulsant therapy does not decrease the incidence of seizure onset more than one week post-injury. In children, there is moderate evidence that prophylactic phenytoin does not reduce the incidence of early or late seizures. The efficacy of anticonvulsants after the development of seizures has not been specifically studied in ABI., Conclusions: Prophylactic anti-convulsants are effective in reducing seizures in the first week post-injury in adults. However, they do not reduce the occurrence of seizures after the first week.

Background: Recent literature has provided new insights into the role of rehabilitation in neurological recovery post-stroke. The present review combines results of animal and clinical research to provide a summary of published information regarding the mechanisms of neural recovery and impact of rehabilitation., Methods: Plasticity of the uninjured and post-stroke brain is examined to provide a background for the examination of brain reorganization and recovery following stroke., Summary and Conclusions: Recent research has confirmed many of the basic underpinnings of rehabilitation and provided new insight into the role of rehabilitation in neurological recovery. Recovery post stroke is dependent upon cortical reorganization, and therefore, upon the presence of intact cortex, especially in areas adjacent to the infarct. Exposure to stimulating and complex environments and involvement in tasks or activities that are meaningful to the individual with stroke serves to increase cortical reorganization and enhance functional recovery. Additional factors associated with neurological recovery include size of stroke lesion, and the timing and intensity of therapy.

Introduction: Aphasia is one of the most common consequences of stroke. Early identification, diagnosis and treatment of language deficits are important steps in maximizing rehabilitation gains. A routine screening test is an invaluable tool in the identification and appropriate referral of patients with potential communication problems. The present study presents an evaluation of the measurement properties of screening tools for aphasia found within the stroke research literature., Methods: Screening tools were identified following searches of the published research literature in stroke. Instruments were reviewed on the basis of reliability, validity, classification sensitivity and practical utility., Results: Six aphasia screening tools were identified. For most tools, information pertaining to measurement properties and clinical utility was limited., Conclusions: The Frenchay Aphasia Screening Test (FAST) appears to be the most widely used and thoroughly evaluated tool found within the stroke research literature. Further evaluation of the measurement properties and clinical utility of screening tools is recommended.