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The integration of medical device systems and general hospital information technology (IT) infrastructure creates a medical device-IT network that requires patient-oriented cybersecurity risk management to ensure patient safety. This study discusses the roles of clinical engineering in taking initiatives in the implementation of the ISO/IEC 80001-1 risk management framework in a hospital environment. Further, we present lessons learned and clinical engineering opportunities in managing medical device cybersecurity, which include development of an integrated systems test lab.Clinical Relevance- This paper highlights Clinical Engineering's leadership role in implementing an effective risk management system for integrated medical device systems to reduce cybersecurity risks to enhance patient care and safety.

The huge amount of existing literature on medical devices by a variety of writers using different terminologies has become difficult to digest. This paper presents a simple framework linking the core activities of medical device regulators, technology assessors, and clinical operators across the lifespans of a medical device. The framework can help policy making and systems operation management to ensure patient safety and optimal performance of medical devices; the framework can equally inform the layperson in using home-use medical devices. In addition, it can serve as a universal common framework among stakeholders for education, communication, and collaboration. Descriptions on framework elements are available in the worldwide literature; one can search the Internet for details without losing the “big-picture” relevance, and then choose the right tools appropriate to their situations. This systems management framework derives from medical device regulatory and quality management systems principles.

While medical device regulations govern manufacturers to ensure product safety, risk management processes in healthcare facilities ensure patient safety in using medical devices. The regulatory and organizational processes are complementary in optimizing patient safety outcomes. Although there are other stakeholders, risk management of medical devices is the principal responsibility of clinical engineering (CE) services professionals in healthcare facilities. In addition to informing CE services, this article uses medical device regulatory concepts for the purposes of demonstrating to healthcare decision-makers that CE services constitute an essential continuum of activities to ensure patient safety. Effective and principled CE services, in turn, gives the medical device regulations greater effect by translating product safety to patient safety.

Performance assurance (PA) is an integral component of clinical engineering medical device risk management. For that reason, the clinical engineering (CE) community has made concerted efforts to define appropriate risk factors and develop quantitative risk models for efficient data processing and improved PA program operational decision making. However, a common framework that relates the various processes of a quantitative risk system does not exist. This article provides a perspective that focuses on medical device quality and risk-based elements of the PA program, which include device inclusion/exclusion, schedule optimization, and inspection prioritization. A PA risk management framework is provided, and previous quantitative models that have contributed to the advancement of PA risk management are examined. A general model for quantitative risk systems is proposed, and further perspective on possible future directions in the area of PA technology is also provided.

Although the Chandler loop model has been used in various in vitro flow studies, there is a lack of guidance on the selection of the appropriate sample volume. The questions of how to determine the appropriate sample volume and its effect on blood activation have not been fully addressed. This study proposes a new criterion for determining sample volume and defines a time-averaged wall shear stress equation for this model. In vitro experiments were performed to investigate the implications of sample volume on blood cell activation in the presence of model stent. Experimental results indicated that in the absence of a stent and for shear stress up to about 56 dyn/cm2, platelet activation was independent of volume and shear. On the other hand, the formation of platelet–leukocyte aggregates was affected by volume as well as the presence of a stent. Doubling blood volume for the same stent resulted in a twofold decrease in platelet microparticle formation and platelet–leukocyte aggregation. These results demonstrate the importance of selecting appropriate sample volume for the Chandler loop model, since it influences blood activation parameters, especially platelet–leukocyte aggregation formation, which can play an important role in material-induced thrombosis. These results have significance for in vitro screening of materials for biocompatibility.

Biomedical Instrumentation & Technology 401 The management of medical devices entails a number of essential components. These include technology assessment, acquisition, inventory control, repair service, in-service education, performance assurance (PA), etc. The PA program, in some cases referred to as preventive maintenance (PM), deals with device operation, performance, and safety. In this paper, PM is regarded as a specific subcomponent or activity of the PA program. The PA program is defined as “a planned and scheduled method of performing inspections for performance verification, preventive maintenance, and safety testing.”1 In this context, performance verification (PV) entails testing according to a written procedure to ensure that equipment is performing within specified performance limits and PM is a planned periodic procedure for cleaning, lubricating, adjusting, and replacing components whose failure may impair equipment function. Safety testing (ST) in this context is performed to verify that equipment is in compliance with electrical safety requirements. Therefore, PA=PV+PM+ST. A similar equation was described by Ridgway2 but with slightly different terminology. In practice, performance assurance includes management of the program and development of test protocols/procedures.

Clinical engineering staff deal with a variety of risk management issues on a daily basis. These issues range from infection control, standards compliance, recalls and safety alerts, patient safety, and incident investigations all the way up to disaster preparedness. Managing device recalls and safety alerts entails several functions, such as processing, risk assessment, distribution, rectification, tracking, and monitoring. This paper discusses the basic elements of an effective recalls and safety alerts management system, thus offering the way to an effective system. The system enabling inputs, activities, and desired outcomes are discussed. The paper also presents our experience in implementing such a system and future possibilities.

The Chandler loop is an artificial circulatory platform for in vitro hemodynamic experiments. In most experiments, the working fluid is subjected to a strain rate field via rotation of the Chandler loop, which, in turn, induces biochemical responses of the suspended cells. For low rotation rates, the strain rate field can be approximated using laminar flow in a straight tube. However, as the rotation rate increases, the effect of the tube curvature causes significant deviation from the laminar straight tube approximation. In this manuscript, we investigate the flow and associated strain rate field of an incompressible Newtonian fluid in a Chandler loop as a function of the governing nondimensional parameters. Analytical estimates of the strain rate from a perturbation solution for pressure driven steady flow in a curved tube suggest that the strain rate should increase with Dean number, which is proportional to the tangential velocity of the rotating tube, and the radius to radius of curvature ratio of the loop. Parametrically varying the rotation rate, tube geometry, and fill ratio of the loop show that strain rate can actually decrease with Dean number. We show that this is due to the nonlinear relationship between the tube rotation rate and height difference between the two menisci in the rotating tube, which provides the driving pressure gradient. An alternative Dean number is presented to naturally incorporate the fill ratio and collapse the numerical data. Using this modified Dean number, we propose an empirical formula for predicting the average fluid strain rate magnitude that is valid over a much wider parameter range than the more restrictive straight tube-based prediction.

The Chandler loop is an artificial circulatory platform for in vitro hemodynamic experiments. In most experiments, the working fluid is subjected to a stress field via rotation of the Chandler loop, which, in turn, induces biochemical responses of the suspended cells. For very low rotation rates, the stress field can be approximated using laminar flow in a straight tube as a model. However, as the rotation rate increases, while still maintaining laminar flow, the effect of the tube curvature causes the stress field to deviate considerably from the straight tube approximation. In this manuscript, we investigate the flow and associated strain rate field of an incompressible Newtonian fluid in a Chandler loop as a function of the governing non-dimensional fluid dynamic parameters. We find that the Dean number, which is proportional to the rotation rate, is the dominant parameter in determining the fluid strain rate. We propose an empirical formula for predicting the average fluid strain rate magnitude in the working fluid that is valid over a wide parameter space to be used in lieu of the common, yet restrictive, straight tube-based prediction.

ObjectivesAmplatzer septal occluder (ASO)-associated cardiac perforation (CP) at our institution prompted this retrospective review.BackgroundCardiac perforation is a rare complication after transcatheter atrial septal defect (ASD) closure.MethodsTo identify CP after transcatheter ASD closure with ASO, cardiac events (CE) describing definite CP, hemopericardium, pericardial effusion, cardiovascular collapse, or sudden death were analyzed. Cardiac events were identified from published literature (MEDLINE), medical device regulating agencies in North America and the European Commission, and AGA Medical Corporation (Golden Valley, Minnesota). Institutional cases were reviewed. Cardiac events were defined as early (pre-discharge) or late (post-discharge).ResultsTwenty-nine CEs were identified. Five were excluded because findings were inconclusive for device-related CP. Ten patients were