Medical Devices-Evidence and Research最新文献

Background: Approximately 2.3 million neonates die annually. UNICEF proposes that the deployment of specialist, quality neonatal care could help reduce neonatal mortality rates by 28% by 2025. Syringe pumps are a key medical device for providing accurate and precise fluid and drug delivery to neonates. However, syringe pumps are expensive, complicated to use and not designed for the additional challenges of providing quality healthcare in low resource healthcare settings. Several open-source designs for low-cost syringe pumps already exist, however, they all have respective limitations.

Objective: To design and test a simple, open-source, screw mechanism, with the potential to be used in a future low-cost syringe pump.

Methods and materials: A low-cost screw mechanism for a syringe pump, using a non-captive stepper motor, was developed. The prototype's accuracy was tested using 5mL, 20mL, 30mL and 60mL syringes at different rates. The rate was measured by recording the changing mass of saline fluid dispensed onto a weighing scale. The mean flow rate error from each run was calculated as the time taken to infuse 75% of the nominal volume, as per the ISO 286020:2020 standard.

Results: The prototype produced a total mean flow rate error of 0.38%±1.62%. All errors were within the 3% limit (Z-score: 0.125) stipulated by the UNICEF and NEST360 target product profile. Compared to the other open-source designs, the prototype has the fewest parts, can accommodate a range of syringe sizes and is more accurate than many of the other open-source designs. Future work should involve testing the device with more viscous fluids, a greater range of rates and microstep settings, and improving the accuracy with further software and hardware development.

Augmented reality head-mounted devices (AR HMDs) are increasingly deployed in healthcare. Given the stringent safety and efficacy requirements of medical settings, proactive quantitative testing of key performance attributes prior to deployment is critical for risk assessment. A systematic performance evaluation framework is essential not only to support clinical adoption but also to secure regulatory approval. This review systematically summarizes hardware, software, and usability assessment methods for AR HMDs in healthcare, analyzes current research and experimental designs, and identifies challenges arising from device heterogeneity, limited coupling with real-world clinical scenarios, and subjective bias. To address these issues, we propose five design principles to guide the development of objective and practical evaluation methods: (1) identify key components based on core functions; (2) prioritize testing by functional contribution; (3) replicate authentic clinical and human-visual conditions; (4) objectify subjective perception; (5) test functionally linked components jointly.

This study focuses on the mid-term management theory of equipment lifecycle and systematically examines the impact of operating room instrument management on operational efficiency optimization. The review mainly covers four key aspects: operator training, information technology application, cost control, and quality assurance. The results indicate that mid-term management plays a crucial role in the full lifecycle management of operating room equipment and plays a key role in improving the quality of operating room operations. This management model is undergoing a profound transformation from experience driven to evidence-based practice, and from single control to system integration. Future research should focus on developing standardized evaluation metrics, scalable digital management platforms, and cross institutional data sharing models for optimizing the lifecycle of medical devices.

[This corrects the article DOI: 10.2147/MDER.S206530.].

Many developers of medical devices face a new reality with the increasing demand for clinical evidence that is generated by clinical investigations. This affects biotechnology companies, start-ups and academic research centres. The participants' informed consent form (ICF), which includes the participant information sheet (PIS), is among the critical documents that are part of the clinical investigation. While many countries around the world follow the principles of good clinical practice (GCP), there are country-specific variations of the ICF requirements. In addition, many of the country guidelines are focused on medicinal products rather than medical devices. Clinical investigations involving medical devices have their unique challenges and need additional guidance to help developers improve the ICF and PIS content. This review provides information on the latest regulatory recommendations from Europe, USA and Asia regarding the content of the ICF and offers practical advice from professionals experienced in preparing ICFs. It also includes some ethical considerations that must be taken into account.

Purpose: While arterial oxyhemoglobin saturation (SaO₂) decreases during sleep in many patients with sleep apnea and pulmonary diseases, personalized oximeters suitable for multi-night monitoring of SpO₂ are not readily available. The present report describes a custom buccal mucosal intraoral oximeter that might provide the opportunity for such long-term monitoring given its strong accuracy in measuring SpO₂ over a range of clinically relevant hypoxemia.

Patients and methods: The intraoral buccal mucosal oximeter was constructed by encapsulating a reflectance pulse oximeter in an overlay of the maxillary dentition. Accuracy was assessed during non-motion conditions in normal participants (n = 12) made progressively hypoxic by decreasing the partial pressure of end-tidal oxygen (PETO₂). CO-oximeter values of SaO₂ from arterial blood constituted the "gold standard" for comparison with the buccal mucosal oximeter's values. The oximeter's pulse rate and an electrocardiogram (ECG) determined heart rate were also compared.

Results: Analysis of 325 paired SaO₂ values from the CO-oximeter and buccal mucosal oximeter yielded the following: r = 0.95; bias = 0.72; and accuracy root-mean-square (A_RMS) = 2.94%. Results from the pulse rate/ECG analysis were: r = 0.99; bias = 0.30; and A_RMS = 2.08 bpm.

Conclusion: These results reveal robust accuracy of the buccal mucosal oximeter measurement of SaO₂ and pulse rate, as shown by good agreement with a "gold standard" over a wide range of arterial hypoxemia. Such clinically acceptable accuracy indicates that this novel reflectance oximeter may prove useful in management of patients with sleep-induced hypoxemia by allowing for long-term monitoring of SaO₂.

Background: Redo cardiac surgery outcomes, including increased transfusions and risk of reoperation, worsen with post-operative bleeding. This study aimed to directly compare the use of an absorbable polysaccharide powder to no hemostatic agent use during planned non-emergent redo cardiac surgery.

Methods: Fifty-one participants in two cohorts underwent planned non-emergent redo cardiac surgery. The retrospective cohort (n = 26) was chosen from redo cardiac surgeries completed between 2019 and 2020, while the prospective cohort (n = 25) included sequential redo cardiac surgeries with the use of an absorbable polysaccharide powder. Patient operative characteristics, along with first 24-hour transfusion use (packed red blood cells (pRBC), fresh frozen plasma (FFP) and platelets (Plts), chest tube outputs (CTO) at 12, 24 and 48 hours, and reoperation rates were compared.

Results: There was a higher non-statistical average of intraoperative pRBC and FFP rates in the retrospective cohort, compared to cases where absorbable polysaccharide powder was used (2 ± 2.9 vs 1.1 ± 1.4 units pRBC, p = 0.414; and 1.4 ± 1.8 vs 0.6 ± 1 units FFP, p = 0.070) while there were statistical differences in Plts use in the retrospective cohort compared to when absorbable polysaccharide powder was used (1 ± 1.3 vs 0.4 ± 0.7 units plts, p = 0.028). Statistically significant lower amounts of CTO in the first 12 hours and the 12-24-hour intervals were found when absorbable polysaccharide powder was used (817 ± 520 vs 558 ± 352 milliliters, p = 0.028; and 1144 ± 704 vs 830 ± 474 milliliters, p = 0.044, respectively). There were three reoperations in the retrospective cohort due to suspected bleeding, compared to no reoperations in the absorbable polysaccharide powder cohort.

Conclusion: This study highlights fewer transfusions, lower CTO, and decreased need for reoperation when using absorbable polysaccharide powder in redo cardiac surgeries. Further randomized trials are needed to more accurately define benefits of absorbable polysaccharide powder in redo cardiac surgeries. Word count: 302.

Importance: Safety issues leading to patient harm and significant costs have been identified in several post-market medical devices. Recently, powerful learning effects (LE) have been documented in numerous medical devices. Correctly attributing safety signals to learning or device effects allows for appropriate corrective actions and recommendations to improve patient safety.

Objective: To develop and assess the statistical performance of an analytic framework to detect the presence of LE and quantify the learning curve (LC).

Design and setting: We generated synthetic datasets based on observed clinical distributions and complex feature correlations among patients hospitalized at US Department of Veterans Affairs facilities. Each dataset represents a hypothetical early experience in the use of high-risk medical devices, with a device of interest and a reference device. The study blinded the analysis team to the data-generation process.

Methods: We developed predictive models using generalized additive models and estimated LC parameters using the Levenberg-Marqualdt algorithm. We evaluated the performance using sensitivity, specificity, and likelihood ratio (LR) in detecting the presence of LE and, if present, the goodness-of-fit of the estimated LC based on the root-mean squared error.

Results: Among the 2483 simulated datasets, the median (IQR) number of cases was 218,000 (116,000-353,000). LE were detected in 2065 of the 2291 datasets for which learning was specified (sensitivity: 90%; specificity: 88%; LR: 7). We adequately estimated the LC in 1632 (81%) of the 2013 datasets in which LE was detected and estimated LC.

Discussion: This study demonstrated the framework to be robust in disentangling LE from device safety signals and in estimating LC.

Conclusion: In medical device safety evaluation, the operator-learning effects associated with the safety of medical devices can be effectively modeled and characterized. This study warrants subsequent framework validation by using real-world clinical datasets.

Background: Human papillomavirus (HPV) is a leading cause of cervical cancer worldwide, with HPV type 16 accounting for roughly half of cases. Although polymerase chain reaction (PCR) is considered the gold standard for HPV detection, its reliance on gel electrophoresis can be costly and require specialized facilities.

Objective: We developed a diagnostic approach integrating PCR with a lateral flow assay to detect HPV type 16 using gold nanoparticles as visible labels.

Methods: Primers targeting the L1 gene of HPV 16 were labeled with 6FAM (forward) and biotin (reverse). Amplified products were applied to lateral flow strips preloaded with streptavidin-gold nanoparticle conjugates. Visible red bands on the test and control lines indicated successful detection.

Results: The optimized assay produced a clear band at ~333 bp by gel electrophoresis and yielded distinct red lines on the lateral flow strip for positive samples. Compared to electrophoresis, this format has a faster turnaround and can reduce costs by eliminating bulky equipment.

Conclusion: This simplified and cost-effective method provides a user-friendly alternative to traditional electrophoresis, making it suitable for resource-limited settings. Further large-scale clinical validation is warranted, including cost analyses and multiplexing for additional genotypes.

Through the ages, the methods of wound dressing have been changing to obtain the best therapeutic effect. The driving force of the process is the development of knowledge and tools. One of the state-of-the-art methods is negative pressure wound therapy. The article presents the results of experimental studies on wound models made in ballistic gel casts and dressed with a vacuum dressing.

Methods: The experiments were performed on samples made of ballistic gel. In the casts, holes were cut out to simulate a wound. Wounds were closed with a dressing connected to a pump, creating a negative pressure. Every model was photographed in two perpendicular sections before and after applying the negative pressure. The changes in shape and size were compared. The numerical model of the wound was also created to confirm experimental observation.

Results: A comparison of wound geometry before and after applying negative pressure reveals a reduction in size in every case. The volume of the wound was reduced by 40%, while its surface area decreased by 27%. This reduction effect was independent of wound size. Furthermore, numerical computations indicate that veins terminating in wounds also reduce in size, with their shape becoming flattened.

Conclusion: The results of experiments and numerical analyses reveal that vacuum dressing can effectively reduce the surface area of the wound by shrinking it and decreasing blood vessel outlets, positively influencing the bleeding reduction. An additional effect is compressive stress in the circumferential direction of the wound, which prevents further development of the wound.