Biomedical Instrumentation and Technology最新文献

Synthetic organic polymers commonly are used in the construction of healthcare product and medical device components. Medical devices often are sterilized to ensure that they are free from viable microorganisms. A common technique to achieve this is using ionizing radiation, usually gamma. A trend exists in industrial sterilization to supplement gamma with alternative accelerator technologies (e.g., X-ray). In the current work, studies were performed to characterize polymer modifications caused by gamma and X-ray sterilization processes and to assess the comparative equivalency. The studies were developed to evaluate two key process parameters: dose and dose rate. Three commonly used polymers were selected: high-density polyethylene, low-density polyethylene, and polypropylene. Four grades of each family were chosen. The dose assessment involved sample exposures to both gamma and X-ray irradiation at two dose levels (30 and 55 kGy). All other processing conditions, including dose rate, were controlled at standard processing levels akin to each sterilization technology. The dose rate assessment expanded on each dose level by introducing two additional dose rate parameters. Subsequent laboratory testing used techniques to characterize physico-chemical properties of the polymers to ascertain equivalency across test groups. Initial results indicated positive levels of equivalency between gamma and X-ray irradiation.

The advancement of novel materials and manufacturing technologies offer opportunities to explore new applications in the space of medical devices. Among these advances, biobased polymers with antimicrobial activity can be used to develop prototypes by additive manufacturing, thereby enabling further exploration with benefits to time and cost. The objective of this research was to assess the effectiveness of polylactic acid (PLA) biopolymer embedded with a copper-based composite (active PLA) to reduce and prevent bacterial growth of microorganisms of concern that may lead to the formation of biofilms. The research was carried out by manufacturing coupons of active PLA using additive manufacturing to test the growth or lack thereof of microorganisms known to form biofilms in medical devices, particularly those with narrow lumens. Testing showed 99.99% antimicrobial effectiveness in reducing Pseudomonas aeruginosa (9027), Escherichia coli (8739), and Klebsiella pneumoniae (4352) growth after 24 hours of exposure. The results confirm the effectiveness of active PLA in preventing microbial growth, which opens the possibility of its use for other medical device applications. Further testing is required, particularly regarding toxicological aspects and potential concerns about the size of copper particles.

During a 12-year period (2011-23), the number of staff in the Clinical Engineering (CE) Department at the Children's Hospital of Eastern Ontario (CHEO) increased from five to more than 20 biomedical equipment technicians/technologists. However, despite this increase in staff, processes did not evolve and procedures that used modern technological and shipping advances were not implemented. The absence of standardized procurement and inventory processes for parts created discrepancies between on-hand inventory and the computerized maintenance management system (CMMS). Owing to inaccurate CMMS information and unsystematic parts documentation, time and money were wasted. This situation led to a lack of confidence in CMMS data, causing staff disengagement, loss of accountability, and limited parts tracking. The current article describes a project that used Lean methodologies and use of the define, measure, analyze, improve, and control structure, including tools such as interviews, a survey, process mapping, and Gemba walks, to create a list of prioritized problems. A total of 16 problems were formulated, four of which were identified as prerequisites to be implemented regardless of prioritization. The four prerequisites described the scope of each problem and potential solutions. The goal of this process was to create a workflow that could save time and money while improving the morale of stakeholders involved in the parts procurement and inventory process.

Objective: The processes of evaluating and selecting health technologies in hospitals have been extensively explored. However, few studies have been specific to U.S. hospitals, and none has approached the subject from the perspective of clinical engineering (CE)/healthcare technology management (HTM) professionals. This study specifically explored the intraorganizational phenomenon of how electronic medical equipment (EME) is evaluated and selected in U.S. hospitals from the perspective of CE/HTM professionals. Methods: The study was qualitative, incorporating semistructured interviews conducted with 10 CE/HTM professionals. Interviews were carried out via Internet conferencing and recorded. The recordings were transcribed and the transcripts analyzed using the constant comparative method and grounded theory. Results: Participants were able to describe details of the intraorganizational processes used to evaluate and select EME within their hospitals. Themes that emerged included coronavirus disease 2019 impact, growing influence over time, multidisciplinary committees, negative outcomes, organizational factors, and process definition/exceptions. Conclusion: This study found a variety of recurring themes associated with the evaluation and selection processes for EME from the perspective of CE/HTM professionals in U.S. hospitals. Participants had varying degrees of power and influence with the processes. The themes may inform CE/HTM professionals seeking to grow their involvement with such processes.

Background: Nitinol is used as the structural framework in numerous types of medical devices (e.g., guidewires, transcatheters, stents). The desire to understand the material compatibility of nitinol with vaporized hydrogen peroxide (VH₂O₂) and nitrogen dioxide (NO₂) sterilization is increasing in healthcare technology. As a result of increased regulatory pressure and capacity limitations related to ethylene oxide (EO) sterilization, the industry is seeking alternative, sustainable sterilization options. Objective: This study sought to characterize the corrosion resistance of nitinol metal alloy wire when exposed to varying levels of VH₂O₂ and NO₂ sterilization. Methods: Scanning electron microscopy (SEM) imaging and energy-dispersive X-ray spectroscopy (EDS) scans were performed to understand the effects of VH₂O₂ and NO₂ sterilization treatments on the surface morphology and chemical composition of nitinol. Results: From the SEM-EDS results, no notable difference was observed when comparing VH₂O₂ and NO₂ test samples with nonsterile control samples. In addition, cyclic potentiodynamic polarization measurements were performed per ASTM F2129-19a to determine corrosion susceptibility. No considerable changes were detected in the electrochemical potential after VH₂O₂ and NO₂ sterilization treatments, when compared with the nonsterile control samples. Conclusion: SEM-EDS and corrosion test results indicated no considerable changes in the surface properties or electrochemical potential of the sterilized samples compared with the nonsterilized control samples. Therefore, nitinol metal showed promising results for compatibility with VH₂O₂ and NO₂ sterilization.

Trends toward the use of irradiator parameter release (also called machine-based release) put pressure on equipment manufacturers to guarantee accuracy and reliability of monitored process parameters. In the specific case of X-ray processing, relevance of these monitored parameters is questionable due to the additional difficulty coming from the fact that the X-ray converter does not have associated parameters or a monitored feedback mechanism. To bridge this gap, this article presents a novel method to verify in real-time consistency of certain X-ray field properties. It covers the description of an X-ray flux monitor and its experimental characterization. The proposed detector can be used as a control and monitoring tool in addition to the conventional "passive" dosimetry per ISO 11137-1 and ISO 11137-3. It can detect photon flux deviation on the order of magnitude of 1%. Its performance would allow real-time monitoring of each pallet being processed and ensure that the correct X-ray beam is directed to the product. Further, the known response of the detector to a product can serve as a validation that the correct product is in front of the beam. Moreover, a detector of this type could contribute to moving from the current dosimetric release to irradiator parameter release. Compared with current practices, benefits would include an increased number of control points used to verify process conformity, real-time information on the radiation field (process output validation), limited manual handling of dosimeters, and verification that the product treated is the same as the performance qualification dose-mapped product.

Background: Infections and injuries have been linked to endoscopes with visible damage or residue. Guidelines recommend visual inspection to identify endoscopes requiring repair or further cleaning. This study sought to evaluate the impact of routine borescope inspections on repair frequency and costs. Methods: Retrospective analysis was performed on a database of endoscope repairs compiled for a three-year period by a large academic medical center that began performing borescope inspections for every endoscope after manual cleaning. Endpoints included total number of repairs, total repair cost, mean cost per repair, mean turnaround time per repair, and procedural usage between repairs. Subgroup analysis was performed to identify repair patterns by endoscope type. Results: The total cost of repairs decreased from $1,212,702 in 2022 to $724,419 in 2024. The number of repairs required annually was similar over time, but reductions occurred in the proportion of repairs classified as major (12.1% to 3.2%) and the mean cost per repair ($4,426 to $2,337; P < 0.001). Mean turnaround time for repairs decreased (from 24.1 to 15.5 days; P < 0.001). Mean number of uses between repairs increased over time (from 52.1 to 87.2; P < 0.001), and the facility decreased the size of the endoscope fleet from 593 to 508. Conclusion: Significant reductions in endoscope repair frequency and cost occurred over time in a large, centralized endoscope processing department that performed borescope inspections of every endoscope after manual cleaning.

When infectious misfolded proteins self-propagate, they cause transmissible spongiform encephalopathies (TSEs) or prion diseases. TSEs are rare, progressive neurodegenerative diseases with long incubation times and are always fatal. Iatrogenic transmission of these diseases is a major concern for human health, and existing methods of decontamination are either ineffective or require caustic chemical treatment followed by extended steam sterilization cycles. Research was undertaken to explore using enzymatic detergents to decontaminate prion-laden surgical devices, equipment, and stainless-steel tools using existing healthcare facility protocols, including cleaning followed by steam or low-temperature sterilization. Several formulations of enzymatic detergents were used to clean stainless steel wires contaminated with infected hamster brain homogenate. Buffering the solutions to achieve a final pH between 8.5 and 9 when diluted, followed by sonication at 45 to 60°C, was effective in rendering prions undetectable in Western blot images. Subsequent sterilization in an autoclave improved the results, causing further prion degradation. Protein misfolding cyclic amplification showed that adding a four-minute prevacuum auto-clave cycle produced a less than 5-log to 6-log reduction in infectious prion proteins using a multienzymatic detergent and a 6-log reduction using a protease enzyme detergent. Increasing the autoclave cycle to 18 minutes generated a consistent 6-log reduction for both formulations, which is the accepted benchmark for effective sterilization.