Biomedical Instrumentation and Technology最新文献

Objective: Borescope examinations of endoscope channels are commonly described in literature, but no studies on surgical instrument lumen inspection have been published recently. Inadequately processed surgical instruments have been implicated in patient infections. This study assessed the utility of borescopes for inspecting surgical instruments. Methods: The study team inspected and photographed sterilized, patient-ready arthroscopic shaver handpieces and suction tips using a tablet camera and borescopes to characterize internal anatomy, defects found in lumens, and the impact of recleaning on debris or residues. Results: Ten suctions and eight shavers were inspected. All suctions had internal ridges and suction holes that were perpendicular to the lumen. All shavers had visible ridges, elbows, and lever mechanisms inside lumens. Of the 18 instruments, 16 (88%) had internal features that appeared rough or jagged and 17 (94%) had visible debris or discoloration in the lumens. Recleaning efforts generally were effective for suctions, but multiple rounds of recleaning with enhanced steps were less effective for shavers, which were replaced. Researchers documented retained soil and brush bristles in several new shavers despite following manufacturer instructions for cleaning and found visible damage and discoloration within five uses. Discussion: This study demonstrated the value of borescope examinations for surgical instrument lumens. Visual inspections identified anatomical features that could influence cleaning effectiveness and detected residual soil, discoloration, and debris in most instruments. The findings suggested that manufacturer cleaning instructions were insufficient and additional cleaning was not always effective. In response, the site's multidisciplinary team strengthened risk assessment protocols and enhanced their cleaning practices.

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.

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.

Objectives: To ensure effectiveness in the endoscope channel cleaning process, using functional brushes that are in good condition is necessary. This study sought to identify the criteria for acquiring, using, and disposing of cleaning brushes at endoscopy facilities in Brazil. We further sought to evaluate the conditions of the cleaning brushes in use in the facilities. Methods: This cross-sectional study was conducted between July 2021 and January 2022. Personnel responsible for processing endoscopes were interviewed regarding the use, processing, and disposal of flexible endoscope cleaning brushes. In addition, the brushes used to clean the equipment were inspected. Results: All participants interviewed reported the practice of brushing endoscope channels. Of them, 60% noted the use of disposable brushes, with 40% using reusable brushes. None of the facilities interviewed reported discarding disposable brushes after use. The protocols for disposal of brushes included disposing due to bristle wear (70%), disposal at the end of the day (20%), and an absence of disposal protocols (10%). In addition, 30% of facilities did not clean the bristles before reintroducing them into the channel/lumen, and no facility had an established routine for cleaning brushes between uses. Inspection of brushes revealed that only 20% of facilities had new brushes with no signs of wear or damage. Conclusion: The use of inappropriate brushes/sponges for cleaning endoscope channels and the lack of criteria for the reuse and disposal of brushes increases the risk of cross-contamination, internal damage to channels, and biofilm formation.

The Medical Device Regulation (MDR) of the European Union (EU) places greater emphasis on the usability of medical devices, with the goal of eliminating or reducing the risk of infection to patients. As this goal also is applicable to sterile packaging, ANSI/AAMI/ISO 11607-1:2019 introduced a usability evaluation requirement for aseptic presentation of terminally sterilized medical devices. In an effort to reduce contamination risks, this requirement focuses specifically on the sterile barrier system (SBS). However, research is limited on evaluating the usability of SBSs and their performance, from an aseptic presentation standpoint, in clinical settings. To address this research gap, we assessed 14 sterile medical devices with five different SBS configurations to elucidate how SBS configuration (type, size, and number of SBS layers) and user satisfaction levels affect usability. A total of 40 experienced clinical nurses participated in 280 individual trials (20 per SBS configuration), which were conducted in a simulated operating room. Ultraviolet fluorescent powder was used to simulate the contamination process and to evaluate the success or failure of the aseptic presentation. Pouch and tray configurations exhibited the best overall performance, while vent bags performed poorly and were considered less acceptable. Double SBS configurations outperformed single SBS configurations. The study highlighted the importance of appropriate SBS symbols to identify SBS layers, which is another patient safety-related requirement of the EU MDR. The current work also includes an analysis of the powder contamination method used in conducting the usability evaluation.

Studies of healthcare providers doffing personal protective equipment, especially gloves, indicate that self-contamination does occur. Although generally this is not hazardous, working with particularly pathogenic organisms, such as Ebola virus and Clostridium difficile, can present a serious health risk. Decontaminating medical gloves before removal can reduce self-contamination and mitigate the spread of these types of pathogens. Also, in cases of extreme shortage, the Centers for Disease Control and Prevention (CDC) has specific recommendations for decontaminating gloves for extended use. Reuse of medical gloves is strongly discouraged by both the CDC and Food and Drug Administration. This work seeks to lay a foundation of testing to evaluate whether a decontamination method is compatible for a given glove type and material. Four potential methods of decontamination (commercial hand soap, alcohol-based hand sanitizer, commercial bleach, and quaternary ammonium solution) were tested on a variety of surgical and patient examination gloves. The method of barrier performance evaluation was ASTM D5151-19, Standard Test Method for Detection of Holes in Medical Gloves. Our results indicated that the performance of the gloves after treatment was highly dependent on the composition of the medical gloves. In general, the surgical gloves in this study performed better than the patient examination gloves, regardless of the material from which they were made. Specifically, vinyl examination gloves tended to have poorer performance. In this study, the number of gloves available to test were limited and therefore statistical significance is beyond the scope of this project.