Origins of Racial and Ethnic Bias in Pulmonary Technologies.

Understanding how biases originate in medical technologies and developing safeguards to identify, mitigate, and remove their harms are essential to ensuring equal performance in all individuals. Drawing upon examples from pulmonary medicine, this article describes how bias can be introduced in the physical aspects of the technology design, via unrepresentative data, or by conflation of biological with social determinants of health. It then can be perpetuated by inadequate evaluation and regulatory standards. Research demonstrates that pulse oximeters perform differently depending on patient race and ethnicity. Pulmonary function testing and algorithms used to predict healthcare needs are two additional examples of medical technologies with racial and ethnic biases that may perpetuate health disparities.

On-demand anchoring of wireless soft miniature robots on soft surfaces.

Untethered soft miniature robots capable of accessing hard-to-reach regions can enable new, disruptive, and minimally invasive medical procedures. However, once the control input is removed, these robots easily move from their target location because of the dynamic motion of body tissues or fluids, thereby restricting their use in many long-term medical applications. To overcome this, we propose a wireless spring-preloaded barbed needle release mechanism, which can provide up to 1.6 N of force to drive a barbed needle into soft tissues to allow robust on-demand anchoring on three-dimensional (3D) surfaces. The mechanism is wirelessly triggered using radio-frequency remote heating and can be easily integrated into existing untethered soft robotic platforms without sacrificing their mobility. Design guidelines aimed at maximizing anchoring over the range of the most biological tissues (kPa range) and extending the operating depth of the device inside the body (up to 75%) are also presented. Enabled by these advances, we achieve robust anchoring on a variety of ex vivo tissues and demonstrate the usage of such a device when integrated with existing soft robotic platforms and medical imaging. Moreover, by simply changing the needle, we demonstrate additional functionalities such as controlled detachment and subsurface drug delivery into 3D cancer spheroids. Given these capabilities, our proposed mechanism could enable the development of a new class of biomedical-related functionalities, such as local drug delivery, disease monitoring, and hyperthermia for future untethered soft medical robots.

Quality and transparency of evidence for implantable cardiovascular medical devices assessed by the CORE-MD consortium.

BACKGROUND AND AIMS: The European Union Medical Device Regulation 2017/745 challenges key stakeholders to follow transparent and rigorous approaches to the clinical evaluation of medical devices. The purpose of this study is a systematic evaluation of published clinical evidence underlying selected high-risk cardiovascular medical devices before and after market access in the European Union (CE-marking) between 2000 and 2021. METHODS: Pre-specified strategies were applied to identify published studies of prospective design evaluating 71 high-risk cardiovascular devices in seven different classes (bioresorbable coronary scaffolds, left atrial appendage occlusion devices, transcatheter aortic valve implantation systems, transcatheter mitral valve repair/replacement systems, surgical aortic and mitral heart valves, leadless pacemakers, subcutaneous implantable cardioverter-defibrillator). The search time span covered 20 years (2000-21). Details of study design, patient population, intervention(s), and primary outcome(s) were summarized and assessed with respect to timing of the corresponding CE-mark approval. RESULTS: At least one prospective clinical trial was identified for 70% (50/71) of the pre-specified devices. Overall, 473 reports of 308 prospectively designed studies (enrolling 97 886 individuals) were deemed eligible, including 81% (251/308) prospective non-randomized clinical trials (66 186 individuals) and 19% (57/308) randomized clinical trials (31 700 individuals). Pre-registration of the study protocol was available in 49% (150/308) studies, and 16% (48/308) had a peer-reviewed publicly available protocol. Device-related adverse events were evaluated in 82% (253/308) of studies. An outcome adjudication process was reported in 39% (120/308) of the studies. Sample size was larger for randomized in comparison to non-randomized trials (median of 304 vs. 100 individuals, P < .001). No randomized clinical trial published before CE-mark approval for any of the devices was identified. Non-randomized clinical trials were predominantly published after the corresponding CE-mark approval of the device under evaluation (89%, 224/251). Sample sizes were smaller for studies published before (median of 31 individuals) than after (median of 135 individuals) CE-mark approval (P < .001). Clinical trials with larger sample sizes (>50 individuals) and those with longer recruitment periods were more likely to be published after CE-mark approval, and were more frequent during the period 2016-21. CONCLUSIONS: The quantity and quality of publicly available data from prospective clinical investigations across selected categories of cardiovascular devices, before and after CE approval during the period 2000-21, were deemed insufficient. The majority of studies was non-randomized, with increased risk of bias, and performed in small populations without provision of power calculations, and none of the reviewed devices had randomized trial results published prior to CE-mark certification.

Facile Fabrication of Multifunctional Hydrogel Nanoweb Coating Using Carboxymethyl Chitosan-Based Short Nanofibers for Blood-Contacting Medical Devices.

Blood-contacting medical devices (BCDs) require antithrombotic, antibacterial, and low-friction surfaces. Incorporating a nanostructured surface with the functional hydrogel onto BCD surfaces can enhance the performances; however, their fabrication remains challenging. Here, we introduce a straightforward method to fabricate a multifunctional hydrogel-based nanostructure on BCD surfaces using O-carboxymethyl chitosan-based short nanofibers (CMC-SNFs). CMC-SNFs, fabricated via electrospinning and cutting processes, are easily sprayed and entangled onto the BCD surface. The deposited CMC-SNFs form a robust nanoweb layer via fusion at the contact area of the nanofiber interfaces. The superhydrophilic CMC-SNF nanoweb surface creates a water-bound layer that effectively prevents the nonspecific adhesion of bacteria and blood cells, thereby enhancing both antimicrobial and antithrombotic performances. Furthermore, the CMC-SNF nanoweb exhibits excellent lubricity and durability on the bovine aorta. The demonstration results of the CMC-SNF coating on catheters and sheaths provide evidence of its capability to apply multifunctional surfaces simply for diverse BCDs.

A narrative commentary about interoperability in medical devices and data used in diabetes therapy from an academic EU/UK/US perspective.

People living with diabetes have many medical devices available to assist with disease management. A critical aspect that must be considered is how systems for continuous glucose monitoring and insulin pumps communicate with each other and how the data generated by these devices can be downloaded, integrated, presented and used. Not only is interoperability associated with practical challenges, but also devices must adhere to all aspects of regulatory and legal frameworks. Key issues around interoperability in terms of data ownership, privacy and the limitations of interoperability include where the responsibility/liability for device and data interoperability lies and the need for standard data-sharing protocols to allow the seamless integration of data from different sources. There is a need for standardised protocols for the open and transparent handling of data and secure integration of data into electronic health records. Here, we discuss the current status of interoperability in medical devices and data used in diabetes therapy, as well as regulatory and legal issues surrounding both device and data interoperability, focusing on Europe (including the UK) and the USA. We also discuss a potential future landscape in which a clear and transparent framework for interoperability and data handling also fulfils the needs of people living with diabetes and healthcare professionals.

Mass spectrometry-based metabolomic analysis as a tool for quality control of natural complex products.

Metabolomics is an area of intriguing and growing interest. Since the late 1990s, when the first Omic applications appeared to study metabolite's pool ("metabolome"), to understand new aspects of the global regulation of cellular metabolism in biology, there have been many evolutions. Currently, there are many applications in different fields such as clinical, medical, agricultural, and food. In our opinion, it is clear that developments in metabolomics analysis have also been driven by advances in mass spectrometry (MS) technology. As natural complex products (NCPs) are increasingly used around the world as medicines, food supplements, and substance-based medical devices, their analysis using metabolomic approaches will help to bring more and more rigor to scientific studies and industrial production monitoring. This review is intended to emphasize the importance of metabolomics as a powerful tool for studying NCPs, by which significant advantages can be obtained in terms of elucidation of their composition, biological effects, and quality control. The different approaches of metabolomic analysis, the main and basic techniques of multivariate statistical analysis are also briefly illustrated, to allow an overview of the workflow associated with the metabolomic studies of NCPs. Therefore, various articles and reviews are illustrated and commented as examples of the application of MS-based metabolomics to NCPs.

Revolutionizing healthcare: Harnessing nano biotechnology with zinc oxide nanoparticles to combat biofilm and bacterial infections-A short review.

A crucial pathogenic mechanism in many bacterial diseases is the ability to create biofilms. Biofilms are suspected to play a role in over 80 % of microbial illnesses in humans. In light of the critical requirement for efficient management of bacterial infections, researchers have explored alternative techniques for treating bacterial disorders. One of the most promising ways to address this issue is through the development of long-lasting coatings with antibacterial properties. In recent years, antibacterial treatments based on metallic nanoparticles (NPs) have emerged as an effective strategy in the fight over bacterial drug resistance. Zinc oxide nanoparticles (ZnO-NPs) are the basis of a new composite coating material. This article begins with a brief overview of the mechanisms that underlie bacterial resistance to antimicrobial drugs. A detailed examination of the properties of metallic nanoparticles (NPs) and their potential use as antibacterial drugs for curing drug-sensitive and resistant bacteria follows. Furthermore, we assess metal nanoparticles (NPs) as powerful agents to fight against antibiotic-resistant bacteria and the growth of biofilm, and we look into their potential toxicological effects for the development of future medicines.

Innovative solution or cause for concern? The use of continuous glucose monitors in people not living with diabetes: A narrative review.

AIMS: Continuous glucose monitors (CGMs) have expanded their scope beyond indicated uses for diabetes management and are gaining traction among people not living with diabetes (PNLD). CGMs track in time glucose levels and are proposed as tools for the early detection of abnormal glucose and a potential solution for its normalisation through behavioural change, particularly, diet personalisation and motivation of physical activity. This becomes relevance given the growing incidence of metabolic conditions, such as type 2 diabetes mellitus (T2DM). Clinical guidelines, however, do not recommend CGMs in contexts outside type 1 diabetes (T1DM) or insulin-treated T2DM. Therefore, there is a visible disconnect between the indicated and real-world usage of these medical devices. While the commercial market for CGMs in PNLD is expanding rapidly, a comprehensive and evidence-based evaluation of the devices' utility in this population has not been done. Therefore, this review aims to formulate a working model for CGM utility in PNLD as proposed by the 'health and wellness' market that advertises and distributes it to these individuals. METHODS: We aim to critically analyse the available research addressing components of the working model, that is (1) detection of abnormal glucose; (2) behavioural change, and (3) metabolic health improvement. RESULTS: We find a lack of consistent and high-quality evidence to support the utility of CGMs for these purposes. We identify significantly under-reserved areas including clinical benchmarks and scoring procedures for CGM measures, device acceptability, and potential adverse effects of CGMs on eating habits in PNLD. We also raise concerns about the robustness of available CGM research. CONCLUSION: In the face of these research gaps, we urge for the commercial claims suggesting the utility of the device in PNLD to be labelled as misleading. We argue that there is a regulatory inadequacy that fuels 'off-label' CGM distribution and calls for the strengthening of post-market clinical follow-up oversight for CGMs. We hope this will help to avert the continued misinformation risk to PNLD and 'off-label' exacerbation of health disparities.

Integrated Devices: A New Regulatory Pathway to Promote Revolutionary Innovation.

Policy Points Current medical device regulatory frameworks date back half a century and are ill suited for the next generation of medical devices that involve a significant software component. Existing Food and Drug Administration efforts are insufficient because of a lack of statutory authority, whereas international examples offer lessons for improving and harmonizing domestic medical device regulatory policy. A voluntary alternative pathway built upon two-stage review with individual component review followed by holistic review for integrated devices would provide regulators with new tools to address a changing medical device marketplace.

A European regulatory pathway for Tidepool loop following clearance in the United States?

The recent clearance by the United States Food and Drug Administration of Tidepool Loop sets an important precedent within the medical device landscape. For the first time, an automated insulin delivery mobile application-based on an algorithm initially designed and developed by users -has been recognised as safe and effective by a regulatory body. The aim of this paper is twofold: firstly, we map out the regulatory pathways and processes that were navigated by Tidepool, the non-profit behind Tidepool Loop, in order to make this landmark moment possible. Secondly, we set out potential approvals processes in the European Union and United Kingdom with a view to examining the challenges to obtaining regulatory clearance for Tidepool Loop in these jurisdictions. In so doing, we highlight the significant differences, not only between the United States and European systems but also between the European Union and Great Britain systems. We conclude by arguing that the complexity encountered when seeking to introduce an innovative solution in different regulatory systems has the potential to act as a disincentive to open source developers from seeking regulatory approvals for such technologies in the future.

A comprehensive review on PFAS including survey results from the EFLM Member Societies.

OBJECTIVES: Per- and polyfluoroalkyl substances (PFASs) are a large class of synthetic chemicals widely used for their unique properties. Without PFAS, many medical device and in vitro diagnostic technologies would not be able to perform their intended purposes. Potential health risks associated with exposure to PFAS influence their use in IVD applications. This paper aims to assess the current situation concerning PFAS, including regulations and legislations for their use. It is important to know what happens to (PFAS) at the end of their lives in medical laboratories. METHODS: A survey was conducted in March 2023 to collect information on the potential emission and end-of-life of PFAS-containing medical technologies in the medical laboratories of the EFLM member societies. A series of questions were presented to the EFLM national societies and the results were documented. RESULTS: Eight respondents participated in the survey, representing EFLM member societies in seven different countries including hospital laboratories, university laboratories, and private laboratories. CONCLUSIONS: PFAS uses in MD and IVD are influenced by several factors, including evolving regulations, advances in technology, safety and efficacy of these substances. Advancements in analytical techniques may lead to more sensitive and precise methods for detecting and quantifying PFAS in biological samples, which can be essential for IVD applications related to biomarker analysis and disease diagnosis. Collaboration among regulatory agencies, industry, research institutions, hospitals, and laboratories on a global scale can aid in establishing harmonized guidelines and standards for the use of PFAS, ensuring consistency and safety within their applications.

IVDCheckR - simplifying documentation for laboratory developed tests according to IVDR requirements by introducing a new digital tool.

OBJECTIVES: A recent challenge for clinical laboratories is the lack of clear guidelines for handling significant modifications of CE-marked assays. The modifications may involve, for example, extending measurement intervals, changing dilution procedures or using non-validated sample materials. The challenge arises due to the amended Regulation (EU) 2017/746 on in vitro diagnostic medical devices (IVDR), which is now poised for implementation, despite the extended transition periods. The IVDR application imposes challenges not only for diagnostic companies but also for clinical laboratories when using laboratory developed tests (LDTs), often referred to as in-house assays. In this context, a coherent and meticulously structured LDT documentation is highly beneficial. While laboratories are obliged to meet the IVDR requirements, the absence of a streamlined framework or guideline hampers the ability to gain a comprehensive overview on the requirements and possible options for their fulfilment. METHODS: To address this issue, we introduce a web based digital tool powered by an R Shiny web application. This tool facilitates a seamless implementation of IVDR requirements for LDTs across diverse laboratory environments in terms of their transparency and validity. Our approach focuses on adequate handling of significant modifications of CE-marked in vitro diagnostic medical devices (IVD). RESULTS: IVDRCheckR is an open-source tool that is easily accessible and free from system dependencies. The tool promotes a seamless process and a guide to enhance transparency, reliability, and validity of laboratory examination results based on LDTs. Additionally, the tool further provides modules for evaluating quality control data and quantitative method comparison data. CONCLUSIONS: Our Shiny web application-based platform is a digitised, user-friendly tool that simplifies the documentation for LDTs according to IVDR requirements with special emphasis on solutions for handling modifications to CE-marked assays.

Economic evaluations of medical devices in paediatrics: a systematic review and a quality appraisal of the literature.

BACKGROUND: Although economic evaluations (EEs) have been increasingly applied to medical devices, little discussion has been conducted on how the different health realities of specific populations may impact the application of methods and the ensuing results. This is particularly relevant for pediatric populations, as most EEs on devices are conducted in adults, with specific aspects related to the uniqueness of child health often being overlooked. This study provides a review of the published EEs on devices used in paediatrics, assessing the quality of reporting, and summarising methodological challenges. METHODS: A systematic literature search was performed to identify peer-reviewed publications on the economic value of devices used in paediatrics in the form of full EEs (comparing both costs and consequences of two or more devices). After the removal of duplicates, article titles and abstracts were screened. The remaining full-text articles were retrieved and assessed for inclusion. In-vitro diagnostic devices were not considered in this review. Study descriptive and methodological characteristics were extracted using a structured template. The Consolidated Health Economic Evaluation Reporting Standards (CHEERS) 2022 checklist was used to assess the quality of reporting. A narrative synthesis of the results was conducted followed by a critical discussion on the main challenges found in the literature. RESULTS: 39 full EEs were eligible for review. Most studies were conducted in high-income countries (67%) and focused on high-risk therapeutic devices (72%). Studies comprised 25 cost-utility analyses, 13 cost-effectiveness analyses and 1 cost-benefit analysis. Most of the studies considered a lifetime horizon (41%) and a health system perspective (36%). Compliance with the CHEERS 2022 items varied among the studies. CONCLUSIONS: Despite the scant body of evidence on EEs focusing on devices in paediatrics results highlight the need to improve the quality of reporting and advance methods that can explicitly incorporate the multiple impacts related to the use of devices with distinct characteristics, as well as consider specific child health realities. The design of innovative participatory approaches and instruments for measuring outcomes meaningful to children and their families should be sought in future research.

Towards user-centered design of medical devices for SUDEP prediction and prevention: Insights from persons with epilepsy and caregivers.

OBJECTIVES: As epilepsy management medical devices emerge as potential technological solutions for prediction and prevention of sudden death in epilepsy (SUDEP), there is a gap in understanding the features and priorities that should be included in the design of these devices. This study aims to bridge the gap between current technology and emerging needs by leveraging insights from persons with epilepsy (PWE) and caregivers (CG) on current epilepsy management devices and understanding how SUDEP awareness influences preferences and design considerations for potential future solutions. METHODS: Two cross-sectional surveys were designed to survey PWE and CG on medical device design features, SUDEP awareness, and participation in medical device research. Data analysis included both qualitative thematic analysis and quantitative statistical analysis. RESULTS: The survey revealed that among 284 responses, CG were more aware of SUDEP than PWE. Comfort was identified as the primary concern regarding wearable medical devices for epilepsy management with significant differences between PWE and CG regarding acceptance and continuous use preferences. The thematic analysis identified integration with daily life, aesthetic and emotional resonance, adaptability to seizure characteristics, and user-centric design specifications as crucial factors to be considered for enhanced medical device adoption. The integration of a companion app is seen as an important tool to enhance communication and data sharing. DISCUSSION: This study reveals that while SUDEP awareness can promote the development of future SUDEP predictive and preventive medical devices, these should be designed to mitigate its impact on daily life and anxiety of both PWE and CG. Comfort and acceptance are seen as key priorities to support continuous use and are seen as a technical requirement of future medical devices for SUDEP prediction and prevention. Widespread adoption requires these technologies to be customizable to adapt to different lifestyles and social situations. A holistic approach should be used in the design of future medical devices to capture several dimensions of PWE and CG epilepsy management journey and uphold communication between healthcare professionals, PWE and CG. CONCLUSION: Data from this study highlight the importance of considering user preferences and experiences in the design of epilepsy management medical devices with potential applicability for SUDEP prediction and prevention. By employing user-centered design methods this research provides valuable insights to inform the development of future SUDEP prediction and prevention devices.

Percutaneous electrical nerve field stimulation for adolescents with irritable bowel syndrome: Cost-benefit and cost-minimization analysis.

Abdominal pain drives significant cost for adolescents with irritable bowel syndrome (IBS). We performed an economic analysis to estimate cost-savings for patients' families and healthcare insurance, and health outcomes, based on abdominal pain improvement with percutaneous electrical nerve field stimulation (PENFS) with IB-Stim® (Neuraxis). We constructed a Markov model with a 1-year time horizon comparing outcomes and costs with PENFS versus usual care without PENFS. Clinical outcomes were derived from a sham-controlled double-blind trial of PENFS for adolescents with IBS. Costs/work-productivity impact for parents were derived from appropriate observational cohorts. PENFS was associated with 18 added healthy days over 1 year of follow-up, increased annual parental wages of $5,802 due to fewer missed work days to care for the child, and $4744 in cost-savings to insurance. Percutaneous electrical field nerve stimulation for adolescents with IBS appears to yield significant cost-savings to patients' families and insurance.

Artificial intelligence for ultrasound scanning in regional anaesthesia: a scoping review of the evidence from multiple disciplines.

BACKGROUND: Artificial intelligence (AI) for ultrasound scanning in regional anaesthesia is a rapidly developing interdisciplinary field. There is a risk that work could be undertaken in parallel by different elements of the community but with a lack of knowledge transfer between disciplines, leading to repetition and diverging methodologies. This scoping review aimed to identify and map the available literature on the accuracy and utility of AI systems for ultrasound scanning in regional anaesthesia. METHODS: A literature search was conducted using Medline, Embase, CINAHL, IEEE Xplore, and ACM Digital Library. Clinical trial registries, a registry of doctoral theses, regulatory authority databases, and websites of learned societies in the field were searched. Online commercial sources were also reviewed. RESULTS: In total, 13,014 sources were identified; 116 were included for full-text review. A marked change in AI techniques was noted in 2016-17, from which point on the predominant technique used was deep learning. Methods of evaluating accuracy are variable, meaning it is impossible to compare the performance of one model with another. Evaluations of utility are more comparable, but predominantly gained from the simulation setting with limited clinical data on efficacy or safety. Study methodology and reporting lack standardisation. CONCLUSIONS: There is a lack of structure to the evaluation of accuracy and utility of AI for ultrasound scanning in regional anaesthesia, which hinders rigorous appraisal and clinical uptake. A framework for consistent evaluation is needed to inform model evaluation, allow comparison between approaches/models, and facilitate appropriate clinical adoption.

Leading in the development, standardised evaluation, and adoption of artificial intelligence in clinical practice: regional anaesthesia as an example.

A recent study by Suissa and colleagues explored the clinical relevance of a medical image segmentation metric (Dice metric) commonly used in the field of artificial intelligence (AI). They showed that pixel-wise agreement for physician identification of structures on ultrasound images is variable, and a relatively low Dice metric (0.34) correlated to a substantial agreement on subjective clinical assessment. We highlight the need to bring structure and clinical perspective to the evaluation of medical AI, which clinicians are best placed to direct.

State of the art medical devices for fluorescence-guided surgery (FGS): technical review and future developments.

BACKGROUND: Medical devices for fluorescence-guided surgery (FGS) are becoming available at a fast pace. The main challenge for surgeons lies in the lack of in-depth knowledge of optical imaging, different technical specifications and poor standardisation, and the selection of the best device based on clinical application. METHODS: This manuscript aims to provide an up-to-date description of the commercially available fluorescence imaging platforms by comparing their mode of use, required settings, image types, compatible fluorophores, regulatory approval, and cost. We obtained this information by performing a broad literature search on PubMed and by contacting medical companies directly. The data for this review were collected up to November 2023. RESULTS: Thirty-two devices made by 19 medical companies were identified. Ten systems are surgical microscopes, 5 can be used for both open and minimally invasive surgery (MIS), 6 can only be used for open surgery, and 10 only for MIS. One is a fluorescence system available for the Da Vinci robot. Nineteen devices can provide an overlay between fluorescence and white light image. All devices are compatible with Indocyanine Green, the most common fluorescence dye used intraoperatively. There is significant variability in the hardware and software of each device, which resulted in different sensitivity, fluorescence intensity, and image quality. All devices are CE-mark regulated, and 30 were FDA-approved. CONCLUSION: There is a prolific market of devices for FGS and healthcare professionals should have basic knowledge of their technical specifications to use it at best for each clinical indication. Standardisation across devices must be a priority in the field of FGS, and it will enhance external validity for future clinical trials in the field.

Spotlights on the trends in performance assessment of qualitative in vitro diagnostic medical devices in transfusion medicine.

For reliable clinical decisions in transfusion medicine, assessing the performance of qualitative tests performed in medical laboratories is critical. When false results are reported, these can lead to an adverse reaction to blood components. Good performance assessment practices are essential for this kind of scenario, and they still remain as one of the many unmet high-priority challenges in this area. This paper aims to provide an overview of the current trends in this field. A review of the IFCC-IUPC. qualitative vocabulary was carried out, and a particular focus was given to the evaluation protocols CLSI EP12-A3 and Eurachem AQA, such as the European Union Regulation for class D in vitro diagnostic medical devices. There is a consistency between the current protocols and recognized performance assessment principles, which are mandatory in transfusion service labs. We believe that a revised imprecision interval approach and models based on emerging qualitative test types may prove beneficial in the long run. It is also important to emphasize the uncertainty of proportions to mitigate the risk of misclassification.

Investigation of the role of von Willebrand factor in shear-induced platelet activation and functional alteration under high non-physiological shear stress.

BACKGROUND: von Willebrand factor (vWF) plays a crucial role in physiological hemostasis through platelet and subendothelial collagen adhesion. However, its role in shear-induced platelet activation and functional alteration under non-physiological conditions common to blood-contacting medical devices (BCMDs) is not well investigated. METHODS: Fresh healthy human blood was treated with an anti-vWF antibody to block vWF-GPIbα interaction. Untreated blood was used as a control. They were exposed to three levels of non-physiological shear stress (NPSS) (75, 125, and 175 Pa) through a shearing device with an exposure time of 0.5 s to mimic typical shear conditions in BCMDs. Flow cytometric assays were used to measure the expression levels of PAC-1 and P-Selectin and platelet aggregates for platelet activation and the expression levels of GPIbα, GPIIb/IIIa, and GPVI for receptor shedding. Collagen/ristocetin-induced platelet aggregation capacity was characterized by aggregometry. RESULTS: The levels of platelet activation and aggregates increased with increasing NPSS in the untreated blood. More receptors were lost with increasing NPSS, resulting in a decreased capacity of collagen/ristocetin-induced platelet aggregation. In contrast, the increase in platelet activation and aggregates after exposure to NPSS, even at the highest level of NPSS, was significantly lower in treated blood. Nevertheless, there was no notable difference in receptor shedding, especially for GPIIb/IIIa and GPVI, between the two blood groups at the same level of NPSS. The block of vWF exacerbated the decreased capacity of collagen/ristocetin-induced platelet aggregation. CONCLUSIONS: High NPSS activates platelets mainly by enhancing the vWF-GPIbα interaction. Platelet activation and receptor shedding induced by high NPSS likely occur through different pathways.