Using Synthesized IMU Data to Train a Long-Short Term Memory-based Neural Network for Unobtrusive Gait Analysis with a Sparse Sensor Setup.

In this work, we evaluated the possibility to use synthesized IMU data for training a deep neural network to generate a more complex, full-body description of the human gait in terms of joint angle trajectories from a sparse sensor setup. In this context, a sparse sensor setup consists of a few sensors attached to human body segments in an unobtrusive manner to possibly provide a monitoring system in an everyday life scenario. Since the relation between the input IMU data and the output joint angle trajectories is highly non-linear, neural networks appear to provide an optimal framework to formulate a mapping description. Especially with respect to periodic signals, recurrent neural networks (RNNs) have gained importance in the recent years. In this work, we have used a special type of RNNs that can be implemented by using long-short term memory (LSTM) cells, which have shown promising results when being applied to sequential data. The artificial training data was generated by a simulative human gait model and virtually attached sensor devices. The trained network was subsequently validated by a dataset that was recorded from a treadmill walking trial using a motion capturing system and an IMU sensor system. The qualitative comparison already shows promising results, however, this study can only be considered to provide preliminary results in this area. Clinical Relevance- This approach has the potential to be applied in the remote assessment of gait behavior during everyday life environments using an unobtrusive sensor net-work. In particular for monitoring older people suffering from an increased fall risk or any significant gait impairments this work is of possible interest.

Impact of Patient- and System-Level Delays on Reperfusion Among Patients With ST-Elevation Myocardial Infarction.

BACKGROUND: Patients with ST-elevation myocardial infarction (STEMI) presenting to percutaneous coronary intervention (PCI)-capable hospitals often experience delays for primary PCI (pPCI). We sought to describe the effect of specific delay intervals and patient/system-level factors on STEMI reperfusion times. METHODS: We analyzed all consecutive patients with STEMI who presented to 2 PCI-capable hospital emergency departments (EDs) between June 2007 and March 2016 who received successful pPCI. We excluded patients with prehospital cardiac arrest. We compared specific system delay intervals, patient characteristics, and in-hospital outcomes among patients who received timely (first medical contact-device ≤90/≤120 minutes) vs delayed >90/>120 minutes) pPCI. RESULTS: Of 1936 patients with STEMI, 1127 (58%) presented directly to a PCI-capable hospital via emergency health services (EHS), 499 (26%) were transferred from the ED of a non-PCI hospital, and 310 (16%) self-presented to the ED of a pPCI-capable hospital. Guideline-recommended reperfusion times were met in 47% of direct-EHS, 42% of transfers, and 33% of self-presenters. Each time interval from first medical contact to device deployment was significantly prolonged in the delayed vs timely reperfusion cohorts across all 3 groups, excepting vascular access time. ED dwell time contributed the most to the difference in median reperfusion time within each group. Time of presentation, comorbidities, and sex were each significantly associated with delayed reperfusion. Within the EHS-direct group, prolonged reperfusion and ED dwell times were significantly associated with increased mortality, major bleeding, and cardiogenic shock. CONCLUSION: Ongoing efforts to identify and reduce ED dwell time and other systemic pPCI delays may improve STEMI outcomes, including mortality.

CONTEXTE: Les patients en infarctus du myocarde avec élévation du segment ST (STEMI) qui se présentent dans un hôpital en mesure d'effectuer une intervention coronarienne percutanée (ICP) doivent souvent attendre pour subir une ICP primaire (ICPP). Nous avons tenté de décrire les effets de différents temps d'attente et facteurs relevant des patients ou du système de santé sur le délai avant la reperfusion lors d'un STEMI. MÉTHODOLOGIE: Nous avons analysé tous les cas consécutifs de patients en STEMI admis entre juin 2007 et mars 2016 au service des urgences de deux hôpitaux en mesure d'effectuer une ICP, et qui ont effectivement subi une ICPP. Les patients qui avaient subi un arrêt cardiaque avant leur arrivée à l'hôpital ont été exclus. Nous avons comparé les temps d'attente à des étapes particulières relevant du système de santé, les caractéristiques des patients et les issues de l'hospitalisation chez les patients qui ont subi une ICPP rapidement (intervalle entre la première prise de contact avec les services médicaux et la pose d'un dispositif ≤ 90/≤ 120 minutes) ou tardivement (intervalle > 90/> 120 minutes). RÉSULTATS: Sur les 1 936 patients ayant subi un STEMI, 1 127 (58 %) ont été conduits par l'entremise des services d'urgences de santé (SUS) directement dans un hôpital en mesure d'effectuer une ICP, 499 (26 %) ont été transférés depuis le service des urgences d'un hôpital n'étant pas en mesure d'effectuer une ICP et 310 (16 %) se sont présentés eux-mêmes au service des urgences d'un hôpital en mesure d'effectuer une ICPP. Les délais avant la reperfusion recommandés dans les lignes directrices ont été respectés dans 47 % des cas où le patient a été conduit par l'entremise des SUS, dans 42 % des cas de transfert et dans 33 % des cas où le patient s'est présenté lui-même. À l'exception du temps écoulé entre l'arrivée au laboratoire de cathétérisme et la création d'un accès vasculaire, les temps d'attente à chacune des étapes entre la première prise de contact avec les services médicaux et la pose d'un dispositif étaient significativement plus longs chez les patients ayant subi une reperfusion tardive que chez ceux ayant subi rapidement une ICPP, et ce, dans les trois groupes de patients. C'est le temps d'attente au service des urgences qui a le plus contribué à la différence entre les groupes en ce qui concerne le délai médian avant la reperfusion. L'heure de l'arrivée au service des urgences, la présence d'affections concomitantes et le sexe étaient tous des facteurs associés de manière significative à une reperfusion tardive. Chez les patients conduits par l'entremise des SUS directement dans un hôpital en mesure d'effectuer une ICP, un délai avant la perfusion et un temps d'attente au service des urgences plus longs étaient associés de manière significative à une hausse de la mortalité, des hémorragies majeures et des chocs cardiogéniques. CONCLUSION: Les efforts actuellement déployés pour reconnaître les sources de retard et réduire les temps d'attente au service des urgences et aux autres étapes avant la réalisation de l'ICPP pourraient permettre d'améliorer l'issue d'un STEMI, y compris la mortalité.

The impact of a telemedicine monitoring system on positive airway pressure adherence in patients with obstructive sleep apnea: a randomized controlled trial.

STUDY OBJECTIVES: First-line therapy for patients with moderate to severe obstructive sleep apnea (OSA) is positive airway pressure (PAP). Although PAP is a highly efficacious treatment, adherence to PAP is still a substantial clinical problem. The objective of this study was to determine whether PAP adherence can be improved with a telemedicine monitoring system. DESIGN: A nonblinded, single-center, randomized controlled trial that compared standard PAP treatment versus PAP treatment and a telemedicine monitoring system SETTING: University sleep disorders program in British Columbia, Canada PATIENTS: Adult patients (≥ 19 yr of age) with moderate to severe OSA (apnea hypopnea index (AHI) ≥ 15 events/hr determined by polysomnography) prescribed PAP INTERVENTIONS: Patients were randomized to either standard care with an autotitrating PAP machine or an autotitrating PAP machine that transmitted physiologic information (i.e., adherence, air leak, residual AHI) daily to a website that could be reviewed. If problems were identified from information from the website, the patient was contacted by telephone as necessary. MEASUREMENTS: PAP adherence after 3 mo, subjective sleep quality, and side effects RESULTS: Seventy-five patients were enrolled; 39 were randomized to telemedicine and 36 to standard care. The mean age ± standard deviation (SD) was 53.5 ± 11.2 yr, mean AHI was 41.6 ± 22.1 events/hr, and 80% of patients were male. After 3 mo, mean PAP adherence was significantly greater in the telemedicine arm (191 min per day) versus the standard arm (105 min per day; mean difference = 87 min, 95% confidence interval (CI): 25-148 min, P = 0.006, unpaired t test). On days when PAP was used, mean adherence was 321 min in the telemedicine arm and 207 min in the standard arm (difference = 113 min, 95% CI: 62-164 min, P < 0.0001). Significant independent predictors of adherence included age, baseline Epworth Sleepiness Scale score, and use of telemedicine. On average, an additional 67 min of technician time was spent on patients in the telemedicine arm compared with the standard arm (P = 0.0001). CONCLUSIONS: PAP adherence can be improved with the use of a web-based telemedicine system at the initiation of treatment.

Reliability of intensive care unit admitting and comorbid diagnoses, race, elements of Acute Physiology and Chronic Health Evaluation II score, and predicted probability of mortality in an electronic intensive care unit database.

BACKGROUND: Although reliability of severity of illness and predicted probability of hospital mortality have been assessed, interrater reliability of the abstraction of primary and other intensive care unit (ICU) admitting diagnoses and underlying comorbidities has not been studied. METHODS: Patient data from one ICU were originally abstracted and entered into an electronic database by an ICU nurse. A research assistant reabstracted patient demographics, ICU admitting diagnoses and underlying comorbidities, and elements of Acute Physiology and Chronic Health Evaluation II (APACHE II) score from 100 random patients of 474 admitted during 2005 using an identical electronic database. Chamberlain's percent positive agreement was used to compare diagnoses and comorbidities between the 2 data abstractors. A kappa statistic was calculated for demographic variables, Glasgow Coma Score, APACHE II chronic health points, and HIV status. Intraclass correlation was calculated for acute physiology points and predicted probability of hospital mortality. RESULTS: Percent positive agreement for ICU primary and other admitting diagnoses ranged from 0% (primary brain injury) to 71% (sepsis), and for underlying comorbidities, from 40% (coronary artery bypass graft) to 100% (HIV). Agreement as measured by kappa statistic was strong for race (0.81) and age points (0.95), moderate for chronic health points (0.50) and HIV (0.66), and poor for Glasgow Coma Score (0.36). Intraclass correlation showed a moderate-high agreement for acute physiology points (0.88) and predicted probability of hospital mortality (0.71). CONCLUSION: Reliability for ICU diagnoses and elements of the APACHE II score is related to the objectivity of primary data in the medical charts.

Clinical manifestations and consequences of obstructive sleep apnea.

Obstructive sleep apnea is a common respiratory disorder that is underdiagnosed and associated with a variety of adverse health and safety consequences. Treatment is effective in improving quality of life and reducing morbidity. This underscores the importance of considering the diagnosis in suitable patients, verifying the diagnosis, and initiating prompt, effective therapy. In this review, the risk factors, symptoms and signs, diagnosis, clinical consequences, and treatment of obstructive sleep apnea are discussed.