Warmed contrast media temperature loss in traditional manifold systems during angiographic procedures.

BACKGROUND: Extrinsic warming of contrast media (CM) to 37 °C before angiographic procedures is performed to improve bolus kinetics and avoid potential adverse effects. Extrinsically warmed CM readily loses temperature after removal from the warming cabinet, but the extent of its cooling has not been previously investigated. PURPOSE: To assess temperature loss of extrinsically warmed CM in tubing of traditional angiographic manifolds during simulated angiography. MATERIAL AND METHODS: In total, 35 scheduled diagnostic angiographic procedures were observed in a hospital setting. Relevant time points of CM use during the procedures were recorded. The shortest, median, and longest procedures were then simulated in the experimental laboratory to measure CM temperatures at specific times at three locations along the tubing system. RESULTS: The angiographic procedures lasted 7.0-26.6 min (median = 11.7 min), with the total duration dependent primarily on the time from contrast being removed from the warming cabinet to the commencement of imaging. During the simulated procedures, consistent patterns of temperature loss were observed. By the last simulated angiographic run, injected CM temperature decreased by 7.4-16.4 °C, depending on procedure length. Most of the heat loss occurred in the tubing between the CM bottle and coronary control syringe. CONCLUSION: During angiographic procedures, prewarmed CM loses its temperature rapidly with the duration of exposure to ambient room temperature. If no additional measures are employed to maintain its temperature outside of the warming cabinet, extrinsic warming has limited impact on injected CM temperature.

Relationship Between Interface Pressures and Pneumatic Cuff Inflation Pressure at Different Assessment Sites of the Lower Limb to Aid Soft Exoskeleton Design.

OBJECTIVE: The aim was to develop a means of predicting interface pressure from cuff inflation pressure during circumferential compression at the lower limb, in order to inform the design of soft exoskeletons. BACKGROUND: Excessive mechanical loading of tissues can cause discomfort and soft tissue injury. Most ergonomic studies on exoskeletons are of interface pressure, but soft exoskeletons apply circumferential pressures similar to tourniquet cuffs by way of cuff inflation pressure. This study details the relationship between interface and cuff inflation pressures for pneumatic tourniquet cuffs. METHOD: Pneumatic cuffs of different widths were inflated to target pressures on (A) a rigid cylinder, (B) the dominant thigh and calf, and (C) knee of healthy participants standing still. Interface pressures were measured under the cuffs using a pressure-sensing mat. Average interface pressures were then compared to cuff inflation pressures. The influence of cuff width, cuff inflation pressure, and participants' anthropometric data on pressure transmission was assessed. RESULTS: A strong linear relationship between cuff inflation pressures and interface pressures was observed. Interface pressures were generally higher than cuff inflation pressures. The efficiency of pressure transmission to the lower limb depended on assessment site, adipose tissue thickness, cuff size, cuff inflation pressure, and possibly limb circumference. Regression equations were developed to predict interface pressures at the thigh, calf, and knee. CONCLUSION: Interface pressures under pneumatic cuffs are influenced by the cuff size, cuff inflation pressure, and tissue compressibility. Predicted interface pressure from cuff inflation pressure and vice versa can be used to aid the design of soft exoskeletons.

Effects of industrial back-support exoskeletons on body loading and user experience: an updated systematic review.

This study is an updated systematic review of papers published in the last 5 years on industrial back-support exoskeletons. The research questions were aimed at addressing the recent findings regarding objective (e.g. body loading, user performance) and subjective evaluations (e.g. user satisfaction), potential side effects, and methodological aspects of usability testing. Thirteen studies of active and twenty of passive exoskeletons were identified. The exoskeletons were tested during lifting and bending tasks, predominantly in laboratory settings and among healthy young men. In general, decreases in participants' back-muscle activity, peak L5/S1 moments and spinal compression forces were reported. User endurance during lifting and static bending improved, but performance declined during tasks that required increased agility. The overall user satisfaction was moderate. Some side effects were observed, including increased abdominal/lower-limb muscle activity and changes in joint angles. A need was identified for further field studies, involving industrial workers, and reflecting actual work situations. Practitioner summary: Due to increased research activity in the field, a systematic review was performed of recent studies on industrial back-support exoskeletons, addressing objective and subjective evaluations, side effects, and methodological aspects of usability testing. The results indicate the efficiency of exoskeletons in back-load reduction and a need for further studies in real work situations. Abbrevaitions: BB: biceps brachii; BF: biceps femoris; CoM: centre of mass; DA: deltoideus anterior; EMG: electromyography; ES: erector spinae; ES-C: erector spinae-cervical; ESI: erector spinae iliocostalis; ESI-L: erector spinae iliocostalis-lumborum; ESL: erector spinae longissimus; ES-L: erector spinae-lumbar; ESL-L: erector spinae longissimus-lumborum; ESL-T: erector spinae longissimus-thoracis; ES-T: erector spinae-thoracic; GM: glutaeus maximus; LBP: low back pain; LD: latissimus dorsi; LPD: local perceived discomfort scale; LPP: local perceived pressure scale; MS: multifidus spinae; MSD: musculoskeletal disorder; M-SFS: modified spinal function sort; NMV: no mean value provided; OA: obliquus abdominis (internus and externus); OEA: obliquus externus abdominis; OIA : obliquus internus abdominis; RA: rectus abdominis; RF: rectus femoris; RoM: range of motion; SUS: system usability scale; T: trapezius (pars Ascendens and Descendens); TA: trapezius pars ascendens; TC: mid-cervical trapezius; TD: trapezius pars descendens; VAS: visual analog scale; VL: vastus lateralis; VM: vastus medialis.

Discomfort/Pain and Tissue Oxygenation at the Lower Limb During Circumferential Compression: Application to Soft Exoskeleton Design.

OBJECTIVE: To establish the relationship between circumferential compression on the lower limb during simulated ramp and staircase profile loading, and the resultant relationship with discomfort/pain and tissue oxygenation. BACKGROUND: Excessive mechanical loading by exoskeletons on the body can lead to pressure-related soft tissue injury. Potential tissue damage is associated with objective oxygen deprivation and accompanied by subjective perception of pain and discomfort. METHOD: Three widths of pneumatic cuffs were inflated at the dominant thigh and calf of healthy participants using two inflation patterns (ramp and staircase), using a computer-controlled pneumatic rig. Participants rated discomfort on an electronic visual analog scale and deep tissue oxygenation was monitored using near infrared spectroscopy. RESULTS: Circumferential compression with pneumatic cuffs triggered discomfort and pain at lower pressures at the thigh, with wider cuffs, and with a ramp inflation pattern. Staircase profile compression caused an increase in deep tissue oxygenation, whereas the ramp profile compression decreased it. CONCLUSION: Discomfort and pain during circumferential compression at the lower limb is related to the width of pneumatic cuffs, the inflation pattern, and the volume of soft tissue at the assessment site. The occurrence of pain is also possibly related to the decrease in deep tissue oxygenation during compression. APPLICATION: Our findings can be used to inform safe and comfortable design of soft exoskeletons to avoid discomfort and possible soft tissue injury.

The effect of simulated circumferential soft exoskeleton compression at the knee on discomfort and pain.

There is a lack of data and guidance on soft exoskeleton pressure contact with the body. The purpose of this research was to study the relationship between circumferential loading at the knee and discomfort/pain, to inform the design of soft exoskeletons/exosuits. The development of discomfort and pain was studied during standing and walking with circumferential compression using a pneumatic cuff. Our results show higher tolerance for intermittent than continuous compression during standing. Discomfort was triggered at pressures ranging from 13.7 kPa (continuous compression) to 30.4 kPa (intermittent compression), and pain at 52.9 kPa (continuous compression) to 60.6 kPa (intermittent compression). During walking, cyclic compression caused an increase in discomfort with time. Higher cuff inflation pressures caused an earlier onset and higher end intensities of discomfort than lower pressures. Cyclic cuff inflation of 10 kPa and 20 kPa was reasonably well tolerated. Practitioner summary Soft exoskeleton compression of the knee was simulated during static and dynamic compression cycles. The results can be used to understand how users tolerate pressure at the knee, and also to understand the levels at which discomfort and pain are experienced. Abbreviations: BMI: body mass index; DDT: discomfort detection threshold; EndVAS: end of experiment rating on visual analog discomfort scale; PDT: pain detection threshold; SD: standard deviation; SE: standard error; TSP: temporal summation of pain; VAS: visual analogue scale.

Games in Times of a Pandemic: Structured Overview of COVID-19 Serious Games.

BACKGROUND: The COVID-19 pandemic introduced an urgent need for effective strategies to disseminate crucial knowledge and improve people's subjective well-being. Complementing more conventional approaches to knowledge dissemination, game-based interventions were developed to create awareness and educate people about the pandemic, hoping to change their attitudes and behavior. OBJECTIVE: This study provided an overview and analysis of digital and analog game-based interventions in the context of the COVID-19 pandemic. As major pandemics and other large-scale disruptive events are expected to increase in frequency in the coming decades, this analysis aimed to inform the design, uptake, and effects of similar future interventions. METHODS: From November 2021 to April 2022, Scopus, Google, and YouTube were searched for articles and videos describing COVID-19-themed game-based interventions. Information regarding authorship, year of development or launch, country of origin, license, deployment, genre or type, target audience, player interaction, in-game goal, and intended transfer effects was extracted. Information regarding intervention effectiveness was retrieved where possible. RESULTS: A diverse assortment of 23 analog and 43 digital serious games was identified, approximately one-third of them (25/66, 38%) through scientific articles. Most of these games were developed by research institutions in 2020 (13/66, 20%) and originated in Europe and North America (38/66, 58%). A limited number (20/66, 30%) were tested on relatively small samples, using a diversity of research methods to assess the potential changes in participants' knowledge, attitudes, and behaviors as well as their gameplay experience. Although most of the evaluated games (11/20, 55%) effectively engaged and motivated the players, increased awareness, and improved their understanding of COVID-19-related issues, the games' success in influencing people's behavior was often unclear or limited. CONCLUSIONS: To increase the impact of similar future interventions aimed at disseminating knowledge and influencing people's attitudes and behaviors during a large-scale crisis, some considerations are suggested. On the basis of the study results and informed by existing game theories, recommendations are made in relation to game development, deployment, and distribution; game users, design, and use; game design terminology; and effectiveness testing for serious games.

The application of additive manufacturing / 3D printing in ergonomic aspects of product design: A systematic review.

Additive Manufacturing (AM) facilitates product personalization and iterative design, which makes it an ideal technology for ergonomic product development. In this study, a systematic review was conducted of the literature regarding the use of AM in ergonomic-product design, and methodological aspects of the studies were analyzed. A literature search was performed using the keywords "3D print*," "additive manufacturing," "ergonomic*" and "human factors". Included were studies reporting the use of AM specifically in ergonomic design of products/prototypes including the detailing of an ergonomic testing methodology used for evaluation. Forty studies were identified pertaining to the fields of medicine, assistive technology, wearable technology, hand tools, testing devices and others. The most commonly used technology was fused deposition modeling with polylactic acid, but the overall preferred material was acrylonitrile butadiene styrene. Various combinations of objective/subjective and qualitative/quantitative product evaluation methods were used. Based on the findings, recommendations were developed to facilitate the choice of most suitable AM technologies and materials for specific applications in ergonomics.

Three-Dimensional Printing of Medical Devices Used Directly to Treat Patients: A Systematic Review.

Until recently, three-dimensional (3D) printing/additive manufacturing has not been used extensively to create medical devices intended for actual clinical use, primarily on patient safety and regulatory grounds. However, in recent years there have been advances in materials, printers, and experience, leading to increased clinical use. The aim of this study was to perform a structured systematic review of 3D-printed medical devices used directly in patient treatment. A search of 13 databases was performed to identify studies of 3D-printed medical devices, detailing fabrication technology and materials employed, clinical application, and clinical outcome. One hundred and ten papers describing one hundred and forty medical devices were identified and analyzed. A considerable increase was identified in the use of 3D printing to produce medical devices directly for clinical use in the past 3 years. This is dominated by printing of patient-specific implants and surgical guides for use in orthopedics and orthopedic oncology, but there is a trend of increased use across other clinical specialties. The prevailing material/3D-printing technology used were titanium alloy/electron beam melting for implants, and polyamide/selective laser sintering or polylactic acid/fused deposition modeling for surgical guides and instruments. A detailed analysis across medical applications by technology and materials is provided, as well as a commentary regarding regulatory aspects. In general, there is growing familiarity with, and acceptance of, 3D printing in clinical use.

Occupational exoskeletons: A roadmap toward large-scale adoption. Methodology and challenges of bringing exoskeletons to workplaces.

The large-scale adoption of occupational exoskeletons (OEs) will only happen if clear evidence of effectiveness of the devices is available. Performing product-specific field validation studies would allow the stakeholders and decision-makers (e.g., employers, ergonomists, health, and safety departments) to assess OEs' effectiveness in their specific work contexts and with experienced workers, who could further provide useful insights on practical issues related to exoskeleton daily use. This paper reviews present-day scientific methods for assessing the effectiveness of OEs in laboratory and field studies, and presents the vision of the authors on a roadmap that could lead to large-scale adoption of this technology. The analysis of the state-of-the-art shows methodological differences between laboratory and field studies. While the former are more extensively reported in scientific papers, they exhibit limited generalizability of the findings to real-world scenarios. On the contrary, field studies are limited in sample sizes and frequently focused only on subjective metrics. We propose a roadmap to promote large-scale knowledge-based adoption of OEs. It details that the analysis of the costs and benefits of this technology should be communicated to all stakeholders to facilitate informed decision making, so that each stakeholder can develop their specific role regarding this innovation. Large-scale field studies can help identify and monitor the possible side-effects related to exoskeleton use in real work situations, as well as provide a comprehensive scientific knowledge base to support the revision of ergonomics risk-assessment methods, safety standards and regulations, and the definition of guidelines and practices for the selection and use of OEs.

Circumferential tissue compression at the lower limb during walking, and its effect on discomfort, pain and tissue oxygenation: Application to soft exoskeleton design.

Soft exoskeletons apply compressive forces at the limbs via connection cuffs to actuate movement or stabilise joints. To avoid excessive mechanical loading, the interface with the wearer's body needs to be carefully designed. The purpose of this study was to establish the magnitude of circumferential compression at the lower limb during walking that causes discomfort/pain. It was hypothesized that the thresholds differ from those during standing. A cohort of 21 healthy participants were tested using two sizes of pneumatic cuffs, inflated at the thigh and calf in a tonic or phasic manner. The results showed lower inflation pressures triggering discomfort/pain at the thigh, with tonic compression, and wider pneumatic cuffs. The thresholds were lower during walking than standing still. Deep tissue oxygenation increased during phasic compression and decreased during tonic compression. According to the findings, circumferential compression by soft exoskeletons is preferably applied at anatomical sites with smaller volumes of soft tissue, using narrow connection cuffs and inflation pressures below 14 kPa.

Cuff Pressure Algometry in Patients with Chronic Pain as Guidance for Circumferential Tissue Compression for Wearable Soft Exoskeletons: A Systematic Review.

In this article, we report on a systematic review of the literature on pressure-pain thresholds induced and assessed by computerized cuff pressure algometry (CPA). The motivation for this review is to provide design guidance on pressure levels for wearable soft exoskeletons and similar wearable robotics devices. In our review, we focus on CPA studies of patients who are candidates for wearable soft exoskeletons, as pain-related physiological mechanisms reportedly differ significantly between healthy subjects and patients with chronic pain. The results indicate that circumferential limb compression in patients most likely becomes painful at ∼10-18 kPa and can become unbearable even below 25 kPa. The corresponding ranges for healthy control subjects are 20-42 kPa (painful limits) and 34-84 kPa (unbearable levels). In addition, the increase of pain with time tends to be significantly higher, and the adaptation to pain significantly lower, than in healthy subjects. The results of this review provide guidance to designers of wearable robotics for populations with chronic pain regarding rates and magnitudes of tissue compression that may be unacceptable to users.

Computerized Cuff Pressure Algometry as Guidance for Circumferential Tissue Compression for Wearable Soft Robotic Applications: A Systematic Review.

In this article, we review the literature on quantitative sensory testing of deep somatic pain by means of computerized cuff pressure algometry (CPA) in search of pressure-related safety guidelines for wearable soft exoskeleton and robotics design. Most pressure-related safety thresholds to date are based on interface pressures and skin perfusion, although clinical research suggests the deep somatic tissues to be the most sensitive to excessive loading. With CPA, pain is induced in deeper layers of soft tissue at the limbs. The results indicate that circumferential compression leads to discomfort at ∼16-34 kPa, becomes painful at ∼20-27 kPa, and can become unbearable even below 40 kPa.