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Aims The aims of the Critical Care Cardiology Trials Network (CCCTN) are to develop a registry to investigate the epidemiology of cardiac critical illness and to establish a multicentre research network to conduct randomised clinical trials (RCTs) in patients with cardiac critical illness. Methods and results The CCCTN was founded in 2017 with 16 centres and has grown to a research network of over 40 academic and clinical centres in the United States and Canada. Each centre enters data for consecutive cardiac intensive care unit (CICU) admissions for at least 2 months of each calendar year. More than 20 000 unique CICU admissions are now included in the CCCTN Registry. To date, scientific observations from the CCCTN Registry include description of variations in care, the epidemiology and outcomes of all CICU patients, as well as subsets of patients with specific disease states, such as shock, heart failure, renal dysfunction, and respiratory failure. The CCCTN has also characterised utilization patterns, including use of mechanical circulatory support in response to changes in the heart transplantation allocation system, and the use and impact of multidisciplinary shock teams. Over years of multicentre collaboration, the CCCTN has established a robust research network to facilitate multicentre registry-based randomised trials in patients with cardiac critical illness. Conclusion The CCCTN is a large, prospective registry dedicated to describing processes-of-care and expanding clinical knowledge in cardiac critical illness. The CCCTN will serve as an investigational platform from which to conduct randomised controlled trials in this important patient population.

Conventional emulated damping, in which velocity feedback is employed in combination with motor current control to emulate damping, is used in a number of mechatronic applications. As known in the field, although such damping should be strictly passive, several implementation factors render this emulation nonpassive and subject to instability, especially with increasing damping ratios. This paper describes an alternative implementation of emulated damping that employs passive motor control, which does not draw energy from a battery or any other power source. The method is specifically described in the context of a brushless direct-current (BLDC) motor; an unique controller architecture is used along with a particular MOSFET switching scheme which employs only a subset of the standard BLDC motor driver and does not require electronic commutation. This paper employs analytical and experimental means to compare damping control with the described passive motor approach, relative to using a conventional BLDC motor control approach. Stability considerations for each scheme are discussed. Benchtop testing demonstrates the advantage of the passive control scheme in terms of providing smooth behavior, enhancing control robustness, preventing energy leaks, and providing accurate behavior. The special cases of unilateral and asymmetric behaviors (i.e., different damping command for each direction of rotation) are also considered.

Older adults may be subject to prolonged bedrest during hospitalization for acute cardiovascular disease, which can contribute to poor functional outcomes posthospitalization. Our objective was to describe mobility status in hospitalized older adults with acute cardiovascular disease.Patients aged ≥ 60 years old in the cardiac intensive care unit and cardiovascular ward at a tertiary care academic centre in Montréal, Québec were prospectively enrolled from April 2019 to March 2020. Activity levels were measured with the ActiGraph GT9X Link 3-axis accelerometer (ActiGraph, Pensacola, FL). Sedentary was defined as lying in bed or in a sitting position. Health-related quality of life (HRQOL) was measured with the Short-Form 36 (SF-36) questionnaire by telephone at 1 month posthospitalization. The primary outcome was percentage of sedentary time during hospitalization.There were 35 patients included in the analysis (75.7 ± 6.9 years old; 45.7% female; 22.9% ischemic heart disease; 20.0% heart failure). Patients spent 91.2% ± 5.5 in a sedentary position during their hospital stay. Mean steps per minute were 1.0 ± 1.2, and mean kcals consumed per day were 116.6 ± 124.5. In the multivariable analysis, a higher percentage of sedentary time and lower steps per minute were each associated with lower total SF-36 scores at 1-month posthospitalization (bothOlder adults with acute cardiovascular disease may be sedentary for a large part of their hospital stay. Increased sedentary time is associated with worse self-reported posthospital HRQOL. Future studies are needed to determine whether interventions to increase activity during hospitalization improve posthospital HRQOL and functional outcomes.Les personnes âgées hospitalisées en raison d’une maladie cardiovasculaire en phase aiguë peuvent être sujettes à un alitement prolongé qui peut contribuer à des résultats fonctionnels médiocres après l’hospitalisation. Notre objectif était de décrire l’état de mobilité des personnes âgées hospitalisées en raison d’une maladie cardiovasculaire en phase aiguë.Nous avons inscrit de façon prospective les patients de ≥ 60 ans de l’unité des soins intensifs cardiaques et de l’unité de cardiologie d’un centre universitaire de soins tertiaires à Montréal, au Québec, d’avril 2019 à mars 2020. Nous avons mesuré les niveaux d’activité physique à l’aide de l’accéléromètre ActiGraph GT9X Link 3-axis (ActiGraph, Pensacola, Floride, É.-U.). Nous avons défini la sédentarité par le fait d’être couché au lit ou en position assise. Nous avons mesuré la qualité de vie liée à la santé (QVLS) à l’aide du questionnaire SF-36 (Short Form-36) par téléphone un mois après l’hospitalisation. Le critère de jugement principal était le pourcentage de temps sédentaire durant l’hospitalisation.Dans l’analyse, on comptait 35 patients (75,7 ± 6,9 ans; 45,7 % de femmes; 22,9 % atteints d’une cardiopathie ischémique; 20,0 % atteints d’insuffisance cardiaque). Les patients passaient 91,2 % ± 5,5 en position sédentaire durant leur séjour à l’hôpital. Les pas moyens par minute étaient de 1,0 ± 1,2, et les kcal moyennes consommées par jour étaient de 116,6 ± 124,5. Dans l’analyse multivariée, un pourcentage plus élevé de temps sédentaire et un nombre inférieur de pas par minute étaient chacun associés à des scores totaux plus faibles au SF-36 un mois après l’hospitalisation (Les personnes âgées atteintes d’une maladie cardiovasculaire en phase aiguë se retrouvent sédentaires pendant une grande partie de leur séjour à l’hôpital. L’augmentation du temps sédentaire est associée à une plus mauvaise QVLS après l’hospitalisation selon les personnes âgées interrogées. Des études ultérieures sont nécessaires pour déterminer si les interventions pour accroître l’activité physique durant l’hospitalisation améliorent la QVLS et les résultats fonctionnels après l’hospitalisation.

This article proposes, describes, and tests a swing-assist walking controller for a stance-controlled, swing-assisted knee prosthesis that aims to combine benefits of passive swing mechanics (e.g., quiet operation, biomimetic function, and low power requirements) with benefits of powered swing assistance (e.g., increased robustness of swing-phase motion and specifically increased toe clearance). A three-participant, multislope, multispeed treadmill walking study was performed using the swing-assist prosthesis and controller, as well as using the participants’ prescribed microprocessor knee devices. The swing-assist device and approach were found to improve user minimum foot clearance during walking at slopes and speeds, and also to improve symmetry of knee motion. Hip power inputs from stance knee release to heel strike indicated that, on average, less hip power was required when using the swing-assist prosthesis, indicating that the observed benefits were likely the result of the knee device and its control methodology, rather than a result of increased hip joint effort.

Although multidimensional frailty scales have been proven to predict mortality and morbidity in cardiac surgery, there is a need for rapid tools that could be easily administered at the point of care. Handgrip strength (HGS) is an attractive option that can be measured in acutely ill and bed-bound patients, although it has yet to be validated in a large cardiac surgery cohort.This is a post hoc analysis of a multicentre prospective study in older patients undergoing coronary artery bypass grafting and/or valve surgery from 2011 to 2019. HGS was measured before surgery and classified by sex-stratified cutoffs. The primary outcome was 1-year mortality and secondary outcomes were 30-day mortality, discharge disposition, and prolonged length of stay.There were 1245 patients included in the analysis (mean age 74.0 ± 6.6 years; 30% female). Weak HGS was associated with advanced age, heart failure, kidney disease, malnutrition, and various frailty scales. In those with weak vs normal HGS, respectively, 1-year mortality was 17% vs 6%, 30-day mortality was 10% vs 3%, prolonged length of stay was 34% vs 19%, and discharge to a health care facility was 45% vs 26% (all P0.001). After adjustment, HGS was predictive of 1-year and 30-day mortalities, with odds ratios of 2.44 (95% confidence interval [CI] 1.39-4.29) and 2.83 (1.38-5.81), respectively. HGS cutoffs of26 kg in men and16 kg in women had the highest predictive performance.HGS is a simple and effective tool to identify patients at higher risk of mortality and protracted recovery after cardiac surgery.

Background: Early mobilization (EM) is safe and feasible in older adults with acute cardiovascular disease (CVD) and may improve posthospitalization patient-centred outcomes. Our objective was to assess posthospitalization health-related quality of life (HRQOL) in older adults with acute CVD undergoing EM. Methods: Patients aged ≥ 60 years with acute CVD undergoing EM at an academic tertiary centre in Montreal, Quebec were prospectively enrolled from January 2018 to January 2020. Functional status was measured using the validated Level of Function Mobility Scale. HRQOL was measured using the Short-Form 36 questionnaire at 1 and 12 months posthospitalization. The primary outcome was the questionnaire’s physical component summary (PCS) score at 1 month posthospitalization. Results: There were 147 patients included in the analysis (aged 75.0 ± 8.7 years; 44.6% female; 48.6% with ischemic heart disease). The mean 1-month PCS score was 34.7 ± 9.7, which was 11.5 points and 8.4 points lower compared to age-matched Canadian normative data for people ages 65-74 years and ≥ 75 years, respectively. The mean PCS score at 12 months (36.5 ± 9.2) and the mean mental component summary scores at 1 and 12 months (36.9 ± 11.1; 40.5 ± 11.5) were lower than those of the age-matched population (all P < 0.0001). In the multivariable analysis, increased age and worse prehospitalization function were associated with lower PCS score at 1 month. Conclusions: Older adults with acute CVD had lower HRQOL at 1 and 12 months posthospitalization than age-matched Canadian norms. Prehospitalization functional status was predictive of poor posthospitalization HRQOL. The EM program was safe and feasible in this patient population. Further studies are needed to determine whether EM can improve posthospitalization patient-centred outcomes in older adults, particularly those with poor prehospitalization functional status. Résumé: Introduction: La mobilisation précoce (MP) est sécuritaire et réalisable chez les personnes âgées atteintes d’une maladie cardiovasculaire (MCV) aiguë et peut permettre d’améliorer les résultats axés sur les patients après l’hospitalisation. Notre objectif était d’évaluer la qualité de vie liée à la santé (QVLS) après l’hospitalisation chez les personnes âgées atteintes d’une MCV aiguë se soumettant à la MP. Méthodes: Les patients ≥ 60 ans atteints d’une MCV aiguë se soumettant à la MP dans un centre universitaire de soins tertiaires à Montréal, au Québec, ont été inscrits de façon prospective de janvier 2018 à janvier 2020. Nous avons mesuré l’état fonctionnel au moyen de l’échelle de mobilité fonctionnelle validée. Nous avons mesuré la QVLS à l’aide du questionnaire d’évaluation de la santé en version abrégée (SF-36, de l’anglais Short-Form 36 questionnaire) un mois et 12 mois après l’hospitalisation. Le principal critère d’évaluation était les scores du sommaire de la composante physique (SCP) du questionnaire un mois après l’hospitalisation. Résultats: Cent quarante-sept patients ont fait l’objet de l’analyse (âgés de 75,0 ± 8,7 ans; 44,6 % de femmes; 48,6 % atteints d’une cardiopathie ischémique). Les scores moyens du SCP après un mois étaient de 34,7 ± 9,7, soit 11,5 points et 8,4 points plus bas que les données normatives canadiennes appariées selon l’âge pour les personnes de 65 à 74 ans et ≥ 75 ans, et ce, respectivement. Les scores moyens du SCP après 12 mois (36,5 ± 9,2) et les scores moyens du sommaire de la composante mentale après un mois et après 12 mois (36,9 ± 11,1; 40,5 ± 11,5) étaient plus bas que les scores de la population appariée selon l’âge (toutes les P < 0,0001). Dans l’analyse multivariée, l’âge avancé et le plus mauvais fonctionnement avant l’hospitalisation ont été associés à un score plus bas du SCP après un mois. Conclusions: Les personnes âgées atteintes d’une MCV aiguë avaient un mois et 12 mois après l’hospitalisation une QVLS inférieure aux normes canadiennes appariées selon l’âge. L’état fonctionnel avant l’hospitalisation permettait de prédire une QVLS médiocre après l’hospitalisation. Le programme de MP était sécuritaire et réalisable pour ces patients. D’autres études sont nécessaires pour déterminer si la MP peut contribuer à l’amélioration des résultats axés sur les patients après l’hospitalisation chez les personnes âgées, particulièrement chez celles qui ont un état fonctionnel médiocre avant l’hospitalisation.

This paper describes a knee prosthesis that provides primarily-passive behavior akin to a state-of-the-art modulated passive microprocessor-controlled knee prosthesis (MPK), but also offers powered stance and swing assistance, which are layered on top of the passive functionality. The combination of both passive and powered behaviors is enabled by a unique electronically-selectable two-speed transmission, which enables the combination of very low output impedance and high resistive torques necessary for passive functionality, while also enabling the generative torque-speed characteristics suitable for stance and swing phase assistance. A control system is described that consolidates behaviors appropriate for a wide range of activities of daily living (ADLs) into six states, with each state providing adaptive torque behaviors appropriate for different phases of gait, whether powered or passive. Experimental results on an individual with transfemoral amputation suggest that the prosthesis and controller provide similar or improved passive behaviors relative to a commercially-available MPK, in addition to providing powered functionality commensurate with a powered prosthesis.

Accumulating evidence from clinical trials suggests that a lower (restrictive) hemoglobin threshold (8% g/dL) for red blood cell (RBC) transfusion, compared with a higher (liberal) threshold (≥10 g/dL) is safe. However, in anemic patients with acute myocardial infarction (MI), maintaining a higher hemoglobin level may increase oxygen delivery to vulnerable myocardium resulting in improved clinical outcomes. Conversely, RBC transfusion may result in increased blood viscosity, vascular inflammation, and reduction in available nitric oxide resulting in worse clinical outcomes. We hypothesize that a liberal transfusion strategy would improve clinical outcomes as compared to a more restrictive strategy.We will enroll 3500 patients with acute MI (type 1, 2, 4b or 4c) as defined by the Third Universal Definition of MI and a hemoglobin10 g/dL at 144 centers in the United States, Canada, France, Brazil, New Zealand, and Australia. We randomly assign trial participants to a liberal or restrictive transfusion strategy. Participants assigned to the liberal strategy receive transfusion of RBCs sufficient to raise their hemoglobin to at least 10 g/dL. Participants assigned to the restrictive strategy are permitted to receive transfusion of RBCs if the hemoglobin falls below 8 g/dL or for persistent angina despite medical therapy. We will contact each participant at 30 days to assess clinical outcomes and at 180 days to ascertain vital status. The primary endpoint is a composite of all-cause death or recurrent MI through 30 days following randomization. Secondary endpoints include all-cause mortality at 30 days, recurrent adjudicated MI, and the composite outcome of all-cause mortality, nonfatal recurrent MI, ischemia driven unscheduled coronary revascularization (percutaneous coronary intervention or coronary artery bypass grafting), or readmission to the hospital for ischemic cardiac diagnosis within 30 days. The trial will assess multiple tertiary endpoints.The MINT trial will inform RBC transfusion practice in patients with acute MI.

Patient and family engagement in research may improve the design, conduct, and dissemination of clinical research, but little is known about whether these stakeholder groups are involved in the design and conduct of randomized clinical trials.To characterize the involvement and role of patient and family representatives in the design and conduct of randomized clinical trials by reviewing randomized clinical trials from 3 peer-reviewed medical and surgical journals with high impact factors.In this systematic review, the first 50 consecutive randomized clinical trials published on or after January 1, 2021, until September 30, 2021, from each of 3 medical and surgical journals with high impact factors were reviewed for patient or family involvement in trial design and/or conduct. The manuscript, supplemental data, and trial registry records were searched for trial design and governance structures. Two independent, blinded reviewers screened citations and extracted data. This study followed the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines.Only 7 of 150 randomized clinical trials (5%) reported patient or family representation in their study design or conduct. Most studies with patient or family representation (n = 5) were from a single journal. Stakeholder involvement was mainly in the execution phase (n = 7), although in 2 studies stakeholders were also involved in the translation phase.The findings of this systematic review suggest that patient or family involvement in the design and conduct of randomized clinical trials in the publications with high impact factors is lacking. We found that when patient or family groups are involved in research, the focus was mainly on the execution phase of research design. There is a need to increase stakeholder involvement in the research design, conduct, and translation of randomized clinical trials.

Family involvement is essential in contemporary health care delivery and is particularly important in cardiac critical care. Opportunities exist for clinicians to engage family in cardiac critical care, but clinicians are often not aware of them. This review describes the rationale, opportunities, and potential benefits to engaging families in cardiac critical care and provides guidance to the practicing cardiovascular clinician.

Aims Frailty is disproportionately prevalent in cardiovascular disease patients and exacerbated during hospital admissions, heightening the risk for adverse events and functional decline. Using the Essential Frailty Toolset (EFT) to target physical weakness, cognitive impairment, malnourishment, and anaemia, we tested a multicomponent targeted intervention to de-frail older adults with acute cardiovascular conditions during their hospital admission. Methods and results The TARGET-EFT trial was a single-center randomized clinical trial at the Jewish General Hospital, Montreal, Canada. We compared a multicomponent de-frailing intervention with usual clinical care. Intervention group patients received exercise, cognitive stimulation, protein supplementation, and iron replacement, as required. In this study, the primary outcome was frailty, as assessed by the SPPB score (Short Physical Performance Battery) at discharge, and the secondary outcome was the SARC-F score (Strength, Assistance walking, Rising from chair, Climbing, Falls) assessed 30 days later. The analysis consisted of 135 patients (mean age of 79.3 years; 54% female) who survived and completed the frailty assessments. Compared with control patients, intervention group patients had a 1.52-point superior SPPB score and a 0.74-point superior SARC-F score. Subgroup analysis suggested that patients with low left ventricular ejection fraction may have attenuated benefits, and that patients who underwent invasive cardiac procedures had the greatest benefits from the intervention. Conclusion We achieved our objective of de-frailing older cardiac inpatients on a short-term basis by improving their physical performance and functioning using a pragmatic multicomponent intervention. This could have positive impacts on their clinical outcomes and ability to maintain independent living in the future. One sentence summary The multicomponent intervention targeted to the deficits of vulnerable older adults hospitalized with acute cardiovascular diseases successfully de-frailed them on a short-term basis, which can have positive implications on their post-discharge health outcomes.

Objective: To review the literature for randomized family-centered interventions with family-centered outcomes in the adult intensive care unit (ICU). Data Sources: We searched MEDLINE, EMBASE, PsycINFO, CINAHL, and the Cochrane Library database from inception until February 2023. Study Selection: We included articles involving randomized controlled trials (RCTs) in the adult critical care setting evaluating family-centered interventions and reporting family-centered outcomes. Data Extraction: We extracted data on author, year of publication, setting, number of participants, intervention category, intervention, and family-centered outcomes. Data Synthesis: There were 52 RCTs included in the analysis, mostly involving communication and receiving information (38%) and receiving care and meeting family member needs (38%). Nearly two-thirds of studies (N = 35; 67.3%) found improvements in at least 1 family-centered outcome. Most studies (N = 24/40; 60%) exploring the impact of family-centered interventions on mental health outcomes showed improvement. Improvements in patient-centered outcomes (N = 7/17; 41%) and healthcare worker outcomes (N = 1/5; 20%) were less commonly found. Conclusions: Family-centered interventions improve family-centered outcomes in the adult ICU and may be beneficial to patients and healthcare workers.

Early mobilization (EM) is recommended in critical care units. However, there is little known about EM in people with acute cardiovascular disease.Consecutive admissions to a tertiary-care cardiovascular intensive care unit (CICU) before and after implementation of an EM program were reviewed. The Level of Function (LOF) Mobility Scale, which ranges from 0 (bed immobile) to 5 (able to walk20 m), was used to measure and guide mobility. The primary outcome was discharge home.There were 1489 patients included in the analysis (preintervention, N = 637; intervention, N = 852). There were no differences in age, sex, or admission for ischemic heart disease (age 68.1 ± 16.1 years; 39.3% female). In the intervention cohort, one-quarter (N = 222; 26.1%) had at least mildly impaired prehospital functional status. The LOF was 4.6 ± 0.7 prehospital, 3.2 ± 1.4 on admission, and 4.2 ± 0.9 on CICU discharge. Half of patients (51.6%) increased their LOF by ≥1 during CICU admission. Nearly all mobility opportunities had a mobility activity (97.0%). The adverse event rate was 0.3% with no life-threatening events, falls, line dislodgements, or health care personnel injuries. The intervention group, compared with the preintervention group, was more likely to be discharged home (83.9% vs 78.3%, P0.007) and had a lower rate of in-hospital death (4.2% vs 6.8%; P = 0.04). When adjusted for age, sex, and comorbid illness, admission LOF was a predictor of discharge to health care facility (odds ratio = 0.72; P0.001).EM is safe and feasible in the CICU and effective at increasing discharge home.

This paper describes a semi-powered ankle prosthesis and corresponding unified controller that provides biomimetic behavior for level and sloped walking without requiring identification of ground slope or modulation of control parameters. The controller is based on the observation that healthy individuals maintain an invariant external quasi-stiffness (spring like behavior between the shank and ground) when walking on level and sloped terrain. Emulating an invariant external quasi-stiffness requires an ankle that can vary the set-point (i.e., equilibrium angle) of the ankle stiffness. A semi-powered ankle prosthesis that incorporates a novel constant-volume power-asymmetric actuator was developed to provide this behavior, and the unified controller was implemented on it. The device and unified controller were assessed on three subjects with transtibial amputations while walking on inclines, level ground, and declines. Experimental results suggest that the prosthesis and accompanying controller can provide a consistent external quasi-stiffness similar to healthy subjects across all tested ground slopes.

When compared to electrically modulated brakes (EMBs), such as a magnetic particle brake, modern brushless direct current (BLDC) motors have substantially higher power densities, and therefore have become an attractive alternative to EMBs for applications requiring controllable modulated resistance (i.e., torque-controllable braking). Unlike brakes, however, which fundamentally guarantee strict passivity, emulating mechanical resistance with a motor does not guarantee passive behavior. In order to enable the use of a motor as a torque-controllable brake with fundamentally guaranteed passivity, this paper presents a control scheme that provides high-fidelity torque tracking and physically guarantees strictly passive behavior. Specifically, this paper: (1) describes model-based control methods for applications requiring high-fidelity torque control and strictly passive impedance; (2) presents an analysis that characterizes the limits of control and tradeoffs of controllability and energy generation associated with using a motor in this manner; and (3) presents experimental results that validate both the system characterization and control performance for the strictly passive controllable impedance approach.

Family engagement is a goal of care delivery in the intensive care unit (ICU). However, currently, no validated instrument for the ICU is designed specifically to measure family engagement. Our objective was to develop a novel family engagement measure.TheThe FAME tool had a high construct validity and required an average of 3.33 minutes to complete. A total of 32 family members completed the FAME questionnaire (mean age: 52.4 ± 14.2 years; 71.4% female; 47% adult child ; 31% spouse/partner). The overall mean FAME score was 84.0% ± 25.2%. Differences in engagement across various domains were identified.The FAME measure is a focused and pragmatic tool to measure the degree and type of family engagement in care of patients in the ICU. Further studies are needed to evaluate the FAME tool in a larger population.La participation de la famille est un objectif établi dans la prestation de soins dans les unités de soins intensifs (USI). Pourtant, il n’existe actuellement aucun instrument validé conçu précisément pour mesurer la participation des familles dans les USI. Notre objectif était d’élaborer une nouvelle façon de mesurer la participation des familles.L’outilL’outil FAME avait une bonne validité conceptuelle et nécessitait en moyenne 3,33 minutes à remplir. Au total, 32 membres de la famille ont rempli le questionnaire FAME (âge moyen : 52,4 ± 14,2 ans; 71,4 % de femmes; 47 % d’enfants adultes; 31 % de conjoints). Le score FAME moyen global a été de 84,0 % ± 25,2 %. Des différences quant à la participation aux divers volets ont été relevées.Le questionnaire FAME est un outil ciblé et pratique qui permet de mesurer le degré et le type de participation de la famille dans les soins des patients séjournant à l’USI. D’autres études doivent être menées pour évaluer l’outil FAME au sein d’une population élargie.

This paper examines the feasibility and control authority of an electronically controlled cold-gas thruster (CGT) as a backpack-worn device for fall prevention for individuals at fall risk. The CGT is comprised of a pressurized air tank combined with a custom electrically actuated high-flow-capacity valve and servo-controlled nozzle, which are employed together to create a thrust intended to arrest an impending fall. In this paper, the authors present the design of the CGT prototype and experimentally investigate its prospective control authority for the purposes of correcting an impending fall.

Background: Limited data exists regarding sex differences in outcome and predictive accuracy of intensive care unit-based scoring systems when applied to cardiac intensive care unit patients. Methods: We reviewed medical records of patients admitted to cardiac intensive care unit from 1 January 2011–31 December 2016. Sex differences in mortality rates and the performance of intensive care unit-based scoring systems in predicting in-hospital mortality were analyzed. Calibration was assessed by the Hosmer-Lemeshow test and locally weighted scatterplot smoothing curves. Discrimination was assessed using the c statistic and receiver-operating characteristic curve. Results: Among 6963 patients, 2713 (39%) were women. Overall in-hospital and cardiac intensive care unit mortality rates were similar in women and men (9.1% vs 9.4%, p=0.67 and 5.9% vs 6%, p=0.88, respectively) and in age and major diagnosis subgroups. Of the scoring systems, Acute Physiology and Chronic Health Evaluation III and Sequential Organ Failure Assessment had poor calibration (Hosmer-Lemeshow p value 0.8). In the subgroups of acute myocardial infarction and heart failure patients, all scores had good calibration (Hosmer-Lemeshow p>0.001) and discrimination (C statistic >0.8) while in diagnosis subgroups with highest mortality, the calibration varied among scores and by sex, and discrimination was poor. Conclusions: No sex differences in mortality were seen in cardiac intensive care unit patients. The mortality predictive value of intensive care unit-based scores is limited in both sexes and variable among different subgroups of diagnoses.

Background Early mobilization (EM) is beneficial in critical care units and in older hospitalized patients, but little is known about EM in older adults with acute cardiovascular disease. Methods Consecutive admissions of adults ≥80 years old to a Cardiac Intensive Care Unit (CICU) prior to and following implementation of a nurse-driven EM program were reviewed. Mobility was measured using the Level of Function (LOF) Mobility Scale, which ranges from 0 (bed immobile) to 5 (able to walk >20 meters). The primary outcome was discharge home. Results There were 412 patients included (N = 234, intervention; N = 178, preintervention). There was no difference in age between groups (overall 86.3 ± 4.8 years old) or sex (overall female N = 215, 52.2%). In the intervention group, functional impairment was present in 89 patients (38.0%) prehospitalization and in 209 patients (89.3%) on admission. Nearly half of patients (N = 107; 45.7%) improved their LOF by ≥1 during admission. Mobilization occurred during nearly all opportunities (838/850; 98.6%), and most mobility activities were completed (2,207/2,553; 86.4%). Adverse events were rare (5/2,207 activities [0.2% adverse event rate]) and transient. Patients in the intervention group were more likely than patients in the preintervention group to be discharged home (74.4 vs. 65.7%, P = 0.047, respectively) and had a lower rate of in-hospital death (6.4 vs. 14.6%, P = 0.006, respectively). There was no difference in mean length of hospital stay, 30-day emergency department visit or hospital re-admission. Conclusion EM is safe in older adults in the CICU and is associated with reduced discharge to healthcare facility and in-hospital mortality.

This article describes the design of a new type of knee prosthesis called a stance-control swing-assist (SCSA) knee prosthesis. The device is motivated by the recognition that energetically passive stance-controlled microprocessor-controlled knees (SCMPKs) offer many desirable characteristics, such as quiet operation, low weight, high-impedance stance support, and an inertially driven swing-phase motion. Due to the latter, however, SCMPKs are also highly susceptible to swing-phase perturbations, which can increase the likelihood of falling. The SCSA prosthesis supplements the behavior of an SCMPK with a small motor that maintains the low output impedance of the SCMPK swing state, while adding a supplemental closed-loop controller around it. This article elaborates upon the motivation for the SCSA prosthesis, describes the design of a prosthesis prototype, and provides human-subject testing data that demonstrate potential device benefits relative to an SCMPK during both nonperturbed and perturbed walking.

People with severe mental illness, consisting of schizophrenia, bipolar disorder, and major depression, have a high burden of modifiable cardiovascular risk behaviors and conditions and have a cardiovascular mortality rate twice that of the general population. People with acute and chronic cardiovascular disease are at a higher risk of developing mental health symptoms and disease. There is emerging evidence for shared etiological factors between severe mental illness and cardiovascular disease that includes biological, genetic, and behavioral mechanisms. This state-of-the art review will describe the relationship between severe mental illness and cardiovascular disease, explore the factors that lead to poor cardiovascular outcomes in people with severe mental illness, propose strategies to improve the cardiovascular health of people with severe mental illness, and present areas for future research focus.

We are proposing a new subfield of engineering, called Inclusion Engineering, that is defined as the use of engineering tools, design, research, and thinking to create environments through which individuals whose abilities and contributions would previously have been marginalized by society can become productive members within society, and at the same time, organizations and society as a whole are made better through more full engagement of the broad spectrum of human abilities.

This paper describes stair ambulation control and functionality of a semi-powered knee prosthesis that supplements nominally passive prosthesis behavior with swing-phase assistance. A set of stair ascent and descent controllers are described. The controllers were implemented in a semi-powered prosthesis prototype, and the prospective benefits of swing assist in stair ambulation were assessed on a group of three participants with unilateral, transfemoral amputation, relative to their respective daily-use prostheses. Results indicate that ambulation with the semi-powered knee resulted in improved stair ascent gait symmetry when compared to the participants’ passive daily-use devices, and increased similitude to healthy stair ascent movement.

Background: Emerging evidence indicates that engaging family members in early mobilization may benefit both patients and family members. However, little is known about the effect of patient and family-member experience and perspectives on mobilization in acute cardiac care. Our goal was to assess the perspectives and experience of patients and their family members regarding early mobilization in acute cardiac care, to better understand patient-related barriers to mobilization and assist in the development of mobilization strategies that increase family-member engagement in care. Methods: Patient and family-member surveys were developed to assess attitudes and knowledge about mobilization, family-members’ roles in providing care, and mobilization care the patients received. Surveys were distributed to patients and their family members over a 4-month period. Results: A total of 101 participants completed the survey (patients, n = 78; family members, n = 23). Most patients (n = 54; 69.2%) agreed or strongly agreed that early mobilization should be routinely performed. Of 72 patients who underwent early mobilization, 60 (83.3%) felt that mobilization helped their recovery. The majority of family members were interested in being involved with mobilization (n = 19; 82.6%). One quarter of family members felt that mobilizing their relatives too soon after admission was potentially dangerous (n = 6; 26.1%). Conclusions: Most patients wish to be mobilized early after admission, and family members want to participate in mobilization efforts. These findings should inform efforts to overcome patient- and family-related barriers to mobilization. Résumé: Introduction: De nouvelles données révèlent que la participation des membres de la famille à la mobilisation précoce peut profiter aux patients et aux membres de la famille. Toutefois, on en connaît peu sur les effets de l’expérience des patients et des membres de la famille et les points de vue sur la mobilisation aux soins cardiaques de courte durée. Notre but était d’évaluer les points de vue et l’expérience des patients et des membres de la famille quant à la mobilisation précoce en soins cardiaques de courte durée afin de mieux comprendre les obstacles des patients à l’égard de la mobilisation et de contribuer à l’élaboration de stratégies de mobilisation qui accroissent la participation des membres de la famille aux soins. Méthodes: Nous avons élaboré des enquêtes destinées aux patients et aux membres de la famille afin d’évaluer les attitudes et les connaissances à l’égard de la mobilisation, les rôles des membres de la famille dans la prestation des soins et l’expérience des patients quant à la prise en charge de la mobilisation. Nous avons distribué les enquêtes aux patients et aux membres de leur famille au cours d’une période de quatre mois. Résultats: Un total de 101 participants ont rempli l’enquête (patients, n = 78; membres de la famille, n = 23). La plupart des patients (n = 54; 69,2 %) se disaient d’accord ou tout à fait d’accord avec le fait de pratiquer systématiquement la mobilisation précoce. Parmi les 72 patients qui avaient eu une mobilisation précoce, 60 (83,3 %) percevaient que la mobilisation précoce favorisait leur rétablissement. La majorité des membres de la famille souhaitait participer à la mobilisation (n = 19; 82,6 %). Un quart des membres de la famille percevaient que la mobilisation trop hâtive de leur proche après l’admission était potentiellement dangereuse (n = 6; 26,1 %). Conclusions: La plupart des patients souhaitent être mobilisés de façon précoce après l’admission, et les membres de la famille veulent participer aux efforts de mobilisation. Ces résultats devraient orienter les efforts visant à surmonter les obstacles des patients et de la famille à l’égard de la mobilisation.

Background Transfemoral prosthesis users’ high fall rate is related to increased injury risk, medical costs, and fear of falling. Better understanding how stumble conditions (e.g., participant age, prosthesis type, side tripped, and swing phase of perturbation) affect transfemoral prosthesis users could provide insight into response deficiencies and inform fall prevention interventions. Methods Six unilateral transfemoral prosthesis users experienced obstacle perturbations to their sound limb in early, mid, and late swing phase. Fall outcome, recovery strategy, and kinematics of each response were recorded to characterize (1) recoveries versus falls for transfemoral prosthesis users and (2) prosthesis user recoveries versus healthy adult recoveries. Results Out of 26 stumbles, 15 resulted in falls with five of six transfemoral prosthesis users falling at least once. By contrast, in a previously published study of seven healthy adults comprising 214 stumbles using the same experimental apparatus, no participants fell. The two oldest prosthesis users fell after every stumble, stumbles in mid swing resulted in the most falls, and prosthesis type was not related to strategy/fall outcomes. Prosthesis users who recovered used the elevating strategy in early swing, lowering strategy in late swing, and elevating or lowering/delayed lowering with hopping in mid swing, but exhibited increased contralateral (prosthetic-side) thigh abduction and trunk flexion relative to healthy controls. Falls occurred if the tripped (sound) limb did not reach ample thigh/knee flexion to sufficiently clear the obstacle in the elevating step, or if the prosthetic limb did not facilitate a successful step response after the initial sound-side elevating or lowering step. Such responses generally led to smaller step lengths, less anterior foot positioning, and more forward trunk flexion/flexion velocity in the resulting foot-strikes. Conclusions Introducing training (e.g., muscle strength or task-specific motor skill) and/or modifying assistive devices (e.g., lower-limb prostheses or exoskeletons) may improve responses for transfemoral prosthesis users. Specifically, training or exoskeleton assistance could help facilitate sufficient thigh/knee flexion for elevating; training or prosthesis assistance could provide support-limb counteracting torques to aid in elevating; and training or prosthesis assistance could help initiate and safely complete prosthetic swing.

Background: Given changes in the care and outcomes of acute myocardial infarction (AMI) patients over the past several decades, we sought to develop prediction models that could be used to generate accurate risk-adjusted mortality and readmission outcomes for hospitals in current practice across Canada. Methods: A Canadian national expert panel was convened to define appropriate AMI patients for reporting and develop prediction models. Preliminary candidate variable evaluation was conducted using Ontario patients hospitalized with a most responsible diagnosis of AMI from April 1, 2015 to March 31, 2018. National data from the Canadian Institute for Health Information was used to develop AMI prediction models. The main outcomes were 30-day all-cause in-hospital mortality and 30-day urgent all-cause readmission. Discrimination of these models (measured by c-statistics) was compared with that of existing Canadian Institute for Health Information models in the same study cohort. Results: The AMI mortality model was assessed in 54,240 Ontario AMI patients and 153,523 AMI patients across Canada. We observed a 30-day in-hospital mortality rate of 6.3%, and a 30-day all-cause urgent readmission rate of 10.7% in Canada. The final Canadian AMI mortality model included 12 variables and had a c-statistic of 0.834. For readmission, the model had 13 variables and a c-statistic of 0.679. Discrimination of the new AMI models had higher c-statistics compared with existing models (c-statistic 0.814 for mortality; 0.673 for readmission). Conclusions: In this national collaboration, we developed mortality and readmission models that are suitable for profiling performance of hospitals treating AMI patients in Canada. RÉSUMÉ: Contexte: Compte tenu des changements apportés au cours des dernières décennies aux soins des patients ayant subi un infarctus aigu du myocarde (IAM) et aux issues d'un tel événement, nous avons voulu élaborer des modèles prédictifs pouvant servir à calculer de façon précise les résultats relatifs à la mortalité et aux réadmissions, ajustés selon les risques, pour les hôpitaux dans la pratique actuelle au Canada. Méthodologie: Un groupe national d'experts canadiens a été mis sur pied et a reçu le mandat de définir les critères appropriés applicables aux patients ayant subi un IAM aux fins de déclaration des cas et d’élaborer des modèles prédictifs. L’évaluation préliminaire des variables proposées a été effectuée à partir de patients hospitalisés en Ontario entre le 1er avril 2015 et le 31 mars 2018 chez lesquels l'IAM était le diagnostic principal à l'origine de l'hospitalisation. Les données à l’échelle nationale de l'Institut canadien d'information sur la santé (ICIS) ont été utilisées pour élaborer des modèles prédictifs d'IAM. Les deux principales issues évaluées étaient la mortalité hospitalière toutes causes confondues à 30 jours et la réadmission urgente toutes causes confondues à 30 jours. Le pouvoir discriminant de ces modèles (mesuré par la statistique C) a été comparé à celui des modèles existants de l'ICIS dans la même cohorte de l’étude. Résultats: Le modèle de mortalité par IAM a été évalué auprès de patients ayant subi un IAM, dont 54 240 en Ontario et 153 523 dans l'ensemble du Canada. Nous avons observé un taux de mortalité hospitalière à 30 jours de 6,3 % et un taux de réadmission urgente à 30 jours toutes causes confondues de 10,7 % au Canada. Le modèle canadien final de prédiction de la mortalité par IAM était constitué de 12 variables et avait une statistique C de 0,834. Pour la réadmission, le modèle comportait 13 variables et présentait une statistique C de 0,679. Le pouvoir discriminant des nouveaux modèles d'IAM présentait une statistique C supérieure à celle des modèles existants (statistique C de 0,814 pour la mortalité et de 0,673 pour la réadmission). Conclusions: Dans le cadre de cette collaboration nationale, nous avons élaboré des modèles prédictifs de la mortalité et de la réadmission hospitalière qui permettent d’établir un profil des résultats obtenus par les hôpitaux traitant des patients ayant subi un IAM au Canada.

Funding Acknowledgements Type of funding sources: None. Background Older adults are at risk for hospital-acquired disability and deconditioning, often leading to the "post-hospitalization syndrome" of accelerated functional decline. We hypothesized that this syndrome could be prevented by a pragmatic multi-faceted intervention, and now report the initial experience and feasibility of our ongoing randomized clinical trial. Methods Patients admitted to the cardiovascular ward at a single academic center are screened with the Essential Frailty Toolset (EFT). Those ≥65 years with frailty (EFT: 3-5) or pre-frailty (EFT: 1-2) are eligible for the TARGET-EFT trial, in which they are randomly allocated to usual care or intervention. The intervention is targeted such that patients with physical weakness receive supervised exercise sessions (in addition to clinically-indicated physiotherapy), those with cognitive impairment receive stimulation activities, those with iron deficiency anemia receive intravenous iron sucrose, and those with malnutrition-related hypoalbuminemia receive protein supplements. The outcome is a composite score representing mobility, disability, activity, discomfort, and mood (EQ-5D-5L) ascertained by a blinded observer on the day of discharge and at 30 days post-hospitalization. Results To date, 77 out of a planned 144 patients have been randomized. The most common reasons for exclusion are age Conclusion The TARGET-EFT intervention is feasible and appears safe for frail and pre-frail patients hospitalized with acute cardiovascular disease. Given that nursing staff, physiotherapists, nutritionists and clinicians already address basic cognitive orientation, mobilization and nutritional/iron supplementation needs, it appears that adding targeted interventions for patients’ specific frailty deficits is feasible when shared amongst allied health professionals.

Older adults undergoing major surgery have increased protein requirements in the postoperative period, but there are limited data describing actual protein intake following cardiac surgery.We performed a prospective sub-study within a registry of older adults ≥60 years of age undergoing cardiac surgery at a tertiary care centre. A dietician administered a food frequency questionnaire before surgery and 1-4 months after surgery. In-hospital food intake was recorded by direct observation for 3 days in the early postoperative period. Food intake was analyzed to calculate the protein intake per kilogram of body weight per day (g/kg/d) during the three phases of care, compared to the dietary reference intake. Frailty was measured by a questionnaire and physical performance tests before surgery. There were 22 patients (8 females, 14 males; 59% frail) enrolled in the study with a mean age of 72.0 ± 7.8 years. The mean protein intake was 1.3 ± 0.5 g/kg/d, 0.7 ± 0.3 g/kg/d, and 1.3 ± 0.6 g/kg/d in the preoperative, early postoperative, and postdischarge periods, respectively (P 0.0001 for early postoperative compared to other periods). Compared to the targeted dietary reference intake of 1.5 g/kg/d, there was a mean protein deficit of 0.8 g/kg/d in the early postoperative period. Only one patient (5%) met the protein dietary reference intake in the early postoperative period.In older adults undergoing cardiac surgery, dietary protein intake was substantially lower than the recommended target in the early postoperative period. Strategies to improve protein intake, particularly in frail older patients, may be considered as a therapeutic target.

This paper describes the design, control, and preliminary assessment of a novel microprocessor-controlled multifunction ankle prosthesis that provides three microprocessor-controlled behaviors—a selectable stiffness equilibrium angle, lockable conformal damping, and swing-phase repositioning. Following a description of the motivation for providing these behaviors, the authors provide a detailed description of the device and walking controller design. This device utilizes a power-asymmetric linear actuator to provide the desired functionality in a compact and lightweight package through a combination of both hydraulic and electromechanical actuation approaches. The device is controlled for level ground walking via a finite-state machine. The functionality of the prosthesis is demonstrated by a set of benchtop experiments that characterize the ability of the prosthesis to provide the three desired behaviors and by an experiment in which the prosthesis was worn by a transtibial amputee during walking. Both sets of experiments indicate that the prosthesis provides the functionality for which it was designed.

This paper presents a control approach for an overground lower limb exoskeleton that is intended to provide guidance and assistance to poorly ambulatory individuals during walking without unduly interfering with their ability to maintain balance. The control approach achieves these objectives by emulating a viscous flow field acting on the lower limb joints. The extent to which the control approach achieves the objectives was assessed in experiments, conducted on five healthy subjects, comparing guidance and disturbance characteristics of the velocity-based controller to a potential-field-based controller. Results show that the flow controller provides a combination of lower guidance error and lower disturbance to the user, relative to the potential-field-based controller. The paper also discusses various potentially beneficial characteristics of the flow controller, such as first-order homogeneous behavior, implicitly combined guidance and assistance behaviors, and improved directionality in error correction relative to a potential-field-based controller.

Introduction: Early mobilization (EM) is safe, feasible, and associated with good outcomes in people with acute CV disease. While studies have explored the perspectives of care providers on mobilization, little is known about patient and family member perspectives and experience with mobilization. Methods: Patient and family member surveys were developed using previously validated surveys (Family Satisfaction with Care in the ICU and the Patient Mobilization Attitudes & Beliefs survey). The survey assessed attitudes toward and knowledge of mobilization, the family member’s role in providing care and the mobilization care they received. Surveys were distributed to patients and their family members in an acute CV unit of a tertiary care centre in Montreal, Canada over a 4-month period. Results: 102 participants completed the survey (78 patients and 24 family members). Most patients (N=54; 69.2%) agreed or strongly agreed that EM should be routinely performed, although nearly half of the patients (N=37, 47.4%) felt that mobilization soon after admission was potentially dangerous. Out of 64 patients who underwent EM, 60 (93.8%) felt that mobilization helped their recovery (Figure). 35 patients (54.7%) felt that family member participation helped their mobilization. Family members included 12 (50.0%) spouses/partners, 10 (41.7%) children, 1 (4.2%) siblings, and 1 parent (4.2%). Most family members felt that mobilizing their relatives too soon after admission was potentially dangerous (N=17, 70.8%). However, family members were interested in being involved with mobilization (N=22; 91.7%) and only a few felt that mobilization should not be routinely performed (N=2; 8.3%). Conclusion: Patients felt that EM helped with their recovery process. Family members were interested in being involved in mobilizing their relatives. Our findings should inform efforts to overcome patient and family-related barriers to mobilization and design an EM program for acute CV care.

Introduction: Measures instituted to prevent the spread of COVID may have an impact on cardiac ICU care practices, such as early mobility (EM) program delivery. A structured EM program was in place in our cardiac ICU prior to COVID. Restrictions on hallway ambulation and patient-provider interaction due to COID led us to modify our EM program to a nurse-assisted, patient-guided program. To our knowledge, there are no studies evaluating patient-guided mobilization in a critical care setting. Thus, our objective was to assess whether self-guided EM was safe and feasible in the cardiac ICU during the COVID period. Methods: We reviewed consecutive records in a tertiary care cardiac ICU over a 2-month period following initiation of the self-guided EM program. Only patients who were COVID negative or presumed negative were admitted to the cardiac ICU. Nurses assessed patients using the Level of Function Mobility Score (range 0 to 5, with higher scores indicating better mobility) and provided the current functional level to patients. Patients used their own smartphones or supplied tablets to view video modules, which guided performance of level-specific mobility activities. Patients with contraindications to mobilization based on prespecified criteria were not mobilized. There were 2 mobilization opportunities per day and 3 activities per opportunity. Results: There were 52 patients admitted to the CICU during the study period (mean age 67.4 ± 16.0 years; 38.5% female). Ten patients (19.2%) had contraindications to mobilization during unit stay; all of these patients were subsequently mobilized. Two-thirds (66.7%; 208/312) of mobilization opportunities had at least one mobility activity. 72.2% (676/936) of prescribed mobility activities were performed. The adverse event rate was 0.6% (4 events/676 activities); none of these were major or life-threatening. There were no falls or line dislodgements. Conclusions: Patient self-guided mobilization was safe and feasible during a period of limited provider-patient interaction in a cardiac ICU. Self-guided EM programs can be considered during periods of restrictions on usual mobility programs. Further studies are needed to evaluate EM in other settings, such as in COVID hospital wards.

Background: Older adults may be subject to prolonged bedrest during hospitalization for acute cardiovascular (CV) disease, which can contribute to poor functional outcomes posthospitalization. Our objective was to describe mobility status in hospitalized older adults with acute CV disease. Methods: Patients aged ≥ 60 years old in the cardiac ICU and CV ward at a tertiary care academic centre in Montreal, Quebec were prospectively enrolled from April 2019 to March 2020. Activity levels were measured with an accelerometer (ActiGraph GT9 Link). Sedentary was defined as lying in bed or in a sitting position. Health-related quality of life (HRQoL) was measured with the Short-Form 36 (SF-36) questionnaire by telephone at 1 month post-hospital discharge. The primary outcome was percentage of sedentary time during hospital stay. Secondary outcomes were step counts, steps per minute, and kcal/day consumption. Results: There were 35 patients included in the analysis (75.7 6.9 years old; 45.7% females; 22.9% ischemic heart disease; 20.0% heart failure). Patients spent 91.2% ± 5.5 in the sedentary position during their hospital stay (range 80.0-100%; Figure ). There was no difference in percentage sedentary time by primary diagnosis or sex. Mean steps per minute were 1.0 ± 1.2 and mean kcals consumed per day were 116.6 ± 124.5. In the multivariable analysis, a lower percentage of sedentary time and lower steps per minute were each associated with lower total SF-36 scores at 1-month posthospitalization (both P Conclusion: Older adults with acute CV disease are sedentary for a large part of their hospital stay. Increased sedentary time is associated with worse self-reported posthospital HRQoL. Future studies are needed to determine whether interventions to increase activity during hospitalization improve posthospital HRQoL and functional outcomes.

Introduction: Early mobilization (EM) is recommended by cardiac surgical societies. However, the optimal method of EM delivery has yet to be determined. Our objective was to assess whether a bedside nurse-driven EM strategy is safe and associated with improved outcomes following cardiac surgery. Methods: Consecutive post-cardiac surgery patients in a cardiovascular intensive care unit (CVICU) at an academic tertiary care centre from 2017 to 2019 prior to and after EM program implementation were reviewed. Postoperative cardiac surgery patients were initially managed in a general ICU and transferred to the CVICU when hemodynamic stability was achieved, typically postoperative day 1 or 2. Functional status was assessed by the nurse on CVICU admission using the Level of Function (LOF) Mobility Scale, which ranges from LOF 0 (bed immobile) to LOF 5 (walks > 50 feet). The nurse uses the LOF score to guide twice-daily level-specific mobility activities. The primary outcome was hospital length of stay. Results: There were 504 patients included in the study (preintervention, N=329; Intervention, N=175). There was no difference in age, sex or comorbid illness between the groups (Table). The LOF was 4.7 ± 0.5 prior to surgery, 3.4 ± 1.1 on CVICU admission, and 4.3 ± 0.6 on CVICU discharge in patients undergoing EM. Patients were mobilized during nearly all mobilization opportunities (98.7%; 685/694). Adverse events were rare (0.4%; 8 events/1901 mobilization activities), minor and transient. There was no difference is postoperative hospital length of stay, in-hospital mortality, discharge home or 30-day hospital re-admission (all P>0.05). Conclusion: A nurse-driven EM program was safe and associated with improvement in functional status in postoperative cardiac surgery patients. The EM program was not associated with improved short-term outcomes. Further studies are needed to understand optimal delivery of EM in cardiac surgical patients.

Background: Early mobilization (EM) is beneficial in general critical care units and in older hospitalized patients, but little is known about EM in older adults with acute cardiovascular disease. Methods: Consecutive admissions of adults ≥ 80 years old to a cardiac ICU at an academic tertiary care centre before (January to December 2017) and after (February 2018 to June 2019) implementation of a structured nurse-driven EM program. Mobility was measured using the validated Level of Function (LOF) Mobility Scale, which ranges from 0 (bed immobile) to 5 (able to walk > 50 feet). The primary outcome was discharge home. Results: There were 412 patients included (N=234, intervention; N=178, preintervention). There was no difference in mean age between groups (overall mean age 86.3±4.8 years old) or sex (overall female N=215, 52.2%). In the intervention group, functional impairment was present in 89 patients (38.0%) prior to hospitalization and in 209 patients (89.3%) on admission. Nearly half of patients undergoing EM (N=107; 45.7%) improved their LOF by ≥1 during cardiac ICU stay. Mobilization occurred during nearly all opportunities (838/850; 98.6%) and most mobility activities were completed (2,207/2,553; 86.4%). Adverse events were rare (5/2,207 activities [0.2%]) and transient (N=5). There were no falls, line dislodgements, or healthcare team injuries). Patients in the intervention group were more likely than patients in the preintervention group to be discharged home (74.4% vs. 65.7%, P=0.047, respectively) and had a lower rate of in-hospital death (6.4% vs. 14.6%, P=0.006, respectively). There was no difference in length of hospital stay or re-admission. In the multivariable analysis, predictors of discharge home were younger age, heart failure, and higher prehospital LOF. Outcomes were similar in adults ≥ age 90. Conclusion: EM is safe in older adults in the cardiac ICU and is associated with reduced discharge to healthcare facility and in-hospital mortality.

This paper presents the design and preliminary testing of an electronically-controlled cold-gas-thruster intended to potentially be used as a backpack-worn device for fall prevention for individuals at fall risk. The device is comprised of a high-pressure air tank, a pilot-operated valve, and a nozzle, which are employed together to create a thrust intended to correct a state of imbalance. The authors first employed modeling and simulation of the thruster-based system to assess feasibility of such a device, and based on these results designed and constructed a device prototype. The prototype was then tested on a rocking block that was used as an experimental model of a standing human subject. Experiments were conducted to assess the angular response of the rocking block starting from various initial tilt angles, both with and without the use of the cold gas thruster. For the experiments with the thruster, the valve was energized at the moment of release, thereby activating the cold-gas thruster, the thrust of which was directed to oppose the “fall.” A comparison between the two cases indicates that the fall prevention prototype increased the region of block stability by more than a factor of three (from a tilt angle of approximately 7 to 26 deg).

The most common gait pathology observed in individuals with cerebral palsy (CP) is crouch gait, which is characterized by excessive knee flexion as well as other symptoms, such as spasticity and muscle weakness. A pair of bilateral knee exoskeletons can potentially reduce crouch gait in this population; doing so would presumably enhance mobility for such individuals. This paper describes the implementation of a knee exoskeleton and control approach intended to improve knee kinematics in an individual with CP. The knee exoskeleton provides extension torque to combat crouch during stance and employs trajectory control to encourage knee flexion and extension during swing. The device and controller were tested on a single adult individual with CP. Though the device and controller achieved the desired local effect, the step length and walking speed of the participant were reduced.

Healthy adults employ one of three primary strategies to recover from stumble perturbations—elevating, lowering, or delayed lowering. The basis upon which each recovery strategy is selected is not known. Though strategy selection is often associated with swing percentage at which the perturbation occurs, swing percentage does not fully predict strategy selection; it is not a physical quantity; and it is not strictly a real-time measurement. The objective of this work is to better describe the basis of strategy selection in healthy individuals during stumble events, and in particular to identify a set of real-time measurable, physical quantities that better predict stumble recovery strategy selection, relative to swing percentage. To do this, data from a prior seven-participant stumble experiment were reanalyzed. A set of biomechanical measurements at/after the perturbation were taken and considered in a two-stage classification structure to find the set of measurements (i.e., features) that best explained the strategy selection process. For Stage 1 (decision between initially elevating or lowering of the leg), the proposed model correctly predicted 99.0% of the strategies used, compared to 93.6% with swing percentage. For Stage 2 (decision between elevating or delayed lowering of the leg), the model correctly predicted 94.0% of the strategies used, compared to 85.6% with swing percentage. This model uses dynamic factors of the human body to predict strategy with substantially improved accuracy relative to swing percentage, giving potential insight into human physiology as well as potentially better informing the design of fall-prevention interventions.

Background: Treatment of ST-elevation myocardial infarction (STEMI) in Canada is protocolized, and timely patient transfer can improve outcomes. Population-based processes of care in Canada for other cardiovascular conditions remain less clear. We aimed to describe the interhospital transfer of Canadian patients with acute cardiovascular disease. Methods: We reviewed the Canadian Institute for Health Information Discharge Abstract Database for adult patients hospitalized with acute cardiovascular disease between 2013 and 2018. We compared patient characteristics and clinical outcomes based on transfer status (transferred, nontransferred) and presenting hospital (teaching, large community, medium community, and small community hospitals). The primary outcome of interest was in-hospital mortality. Results: There were 476,753 patients with primary acute cardiovascular diagnoses, 48,579 (10.2%) of whom were transferred. Transferred patients were more frequently younger, male, and had fewer comorbidities. The most common diagnoses among transferred patients were non-STEMI (44.2%), STEMI (29.0%), and congestive heart failure (9.4%). Using teaching hospitals as a reference, transfer to large and medium community hospitals was associated with lower hospital mortality (adjusted odds ratio: 0.83, 95% confidence interval: 0.75-0.91 and 0.45, 95% confidence interval: 0.39-0.52, respectively). Conclusions: Approximately 10% of patients with acute cardiovascular conditions are transferred to another hospital. Patient transfer may be associated with lower in-hospital mortality, with possible variability based on diagnosis, comorbidities, hospital of origin, and destination hospital. Further investigation into the optimization of care for patients with acute cardiovascular disease, including transfer practices, is warranted as regionalized care models continue to develop. Résumé: Introduction: Au Canada, le traitement de l’infarctus du myocarde avec sus-décalage du segment ST (STEMI) découle d’un protocole qui prévoit au moment opportun le transfert des patients pour permettre d’améliorer les résultats cliniques. On n’en sait encore peu sur les processus de soins auprès de la population canadienne en ce qui concerne les autres maladies cardiovasculaires. Nous avions pour objectif de décrire les transferts interhospitaliers de patients canadiens atteints d’une maladie cardiovasculaire aiguë. Méthodes: Nous avons passé en revue les résumés de la base de données de l’Institut canadien d’information sur la santé sur les congés des patients hospitalisés atteints d’une maladie cardiovasculaire aiguë entre 2013 et 2018. Nous avons comparé les caractéristiques des patients et les résultats cliniques en fonction du statut du transfert (patients transférés ou non transférés) et de l’hôpital de destination (hôpitaux d’enseignement, grands hôpitaux communautaires, hôpitaux communautaires moyens et petits hôpitaux communautaires). Le principal critère étudié était la mortalité intrahospitalière. Résultats: Parmi les 476 753 patients qui avaient un diagnostic principal de maladie cardiovasculaire aiguë, 48 579 (10,2 %) ont été transférés. Les patients transférés étaient plus fréquemment jeunes, de sexe masculin, et avaient peu de comorbidités. Les diagnostics les plus fréquents parmi les patients transférés étaient les non-STEMI (44,2 %), les STEMI (29,0 %) et l’insuffisance cardiaque congestive (9,4 %). En utilisant comme référence les hôpitaux d’enseignement, les transferts vers de grands hôpitaux communautaires et des hôpitaux communautaires moyens étaient associés à une plus faible mortalité intrahospitalière (ratio d’incidence approché ajusté : 0,83, intervalle de confiance à 95 %, 0,75-0,91 et 0,45, intervalle de confiance à 95 %, 0,39-0,52, et ce, respectivement). Conclusions: Approximativement 10 % des patients atteints d’une maladie cardiovasculaire aiguë sont transférés vers un autre hôpital. Le transfert des patients peut être associé à une plus faible mortalité intrahospitalière et montrer une variabilité en fonction du diagnostic, des comorbidités, de l’hôpital d’origine et de l’hôpital de destination. D’autres études liées à l’optimisation des soins des patients atteints d’une maladie cardiovasculaire aiguë, qui porteront de plus sur les pratiques de transfert, sont justifiées puisque l’élaboration de modèles de soins régionaux se poursuit.

This paper presents the design and implementation of a controller for stair ascent and descent in a primarily-passive stance-controlled swing-assist (SCSA) prosthesis. The prosthesis and controller enable users to perform both step-over and step-to stair ascent and descent. The efficacy of the controller and SCSA prosthesis prototype in providing improved stair ambulation was tested on a unilateral transfemoral amputee in experiments that employed motion capture apparatus to compare joint kinematics with the SCSA prosthesis, relative to performing the same activity with a microprocessor-controlled daily-use passive prosthesis. Results suggest that the SCSA knee significantly decreases compensatory motion during stair activity when compared to the passive prosthesis.

This paper describes the implementation of a movement control method for lower limb exoskeletons with single-joint actuation. In such applications, the single-joint must coordinate movement with other non-controlled joints. The authors have previously proposed a multi-joint control method called a flow controller, which provides several desirable characteristics for such assistance. In this paper, the authors adapt the fundamentally multi-joint flow control approach to a system with a single actuated joint, but with multiple movement degrees of freedom. The single degree of actuation flow control method was implemented on a representative system, specifically a knee exoskeleton that coordinates assistance with ipsilateral thigh movement during walking. The ability of the controller and knee exoskeleton to appropriately influence knee movement was evaluated in level walking experiments on three subjects with unilateral lower-limb impairment. Results show the device and controller provide improvements in knee movement in all subjects. Subjective feedback from the subjects indicates a high level of comfort with the controller.