1 Scope of applicationSuitable for microbiological testing of settling bacteria, planktonic bacteria workbenches, and workers' hands in dust-free workshops.2 Definitions2.1 Floating bacteria: live microbial particles suspended in the air, using specialized methods The instrument is used to reproduce visible bacterial activity through specialized culture medium under suitable growth conditions.2.2 Settling bacteria: live microbial particles in the air that reproduce to visible bacterial activity under suitable growth conditions through specialized culture media.2.3 CFU: Colony forming unit.3 Testing Methods3.1 Preparation of reagents/culture media3.1.1 According to the sampling quantity, prepare 0.9% physiological saline and soy casein agar medium according to the prescribed requirements. Divide the prepared medium into triangular bottles, seal them with rubber stoppers, and wrap them with white paper; Use a pipette to transfer 10ml of 0.9% physiological saline solution into a test tube, seal it with a stopper, and wrap it with white paper. Wrap the corresponding number of pipettes and cotton swabs; Place the petri dish into the stainless steel container In the poison cylinder, all items are extinguished by high-pressure steam at 121 ℃ Bacteria for 15 minutes;3.1.2 Extinguish After the completion of the culture, part of the culture medium will be poured into a petri dish and used to detect planktonic and settling bacteria. If not used on the same day, it should be stored at a low temperature of 2-8 ℃. Place some of the culture medium in a constant temperature water bath at 45 ± 5 ℃. After the physiological saline tube has cooled down, it can be sampled in a dust-free workshop;3.2 The sampling steps for settling bacteria are as follows:3.2.1 Mark the solidified culture dish according to the sampling position;3.2.2 When arranging sampling points, try to avoid return air vents with concentrated dust particles as much as possible;3.2.3 Place the culture dish on a workbench about 0.8-1.5m above the ground, remove the lid of the dish, and expose the culture medium to the air for 30 minutes for sampling;After all sampling is completed, cover the culture dish and invert it. 3.2.5 When the culture dish is used for testing, in order to avoid the impact caused by the transportation or handling of the culture dish, a negative control test should be conducted simultaneously. One control dish should be taken from each time or area, operated in the same way as the sampling dish but without exposing the sample. Then, it should be placed in the culture box together with the sampled culture dish for cultivation, and the results should be sterile.3.3 The sampling steps for planktonic bacteria are as follows:3.3.1 Before sampling, use a suppressor Poison elimination The top cover, turntable, and inner and outer surfaces of the toxic sampler;3.3.2 Turn on the planktonic bacteria sampler to eliminate residual bacteria in the instrument Evacuate the toxic agent for no less than 5 minutes, check the flow rate, and adjust the sampling parameters according to the sampling volume. Each sampling point should sample no less than 500L; When arranging sampling points, the sampling point position should be about 0.8-1.5m above the ground, and the measurement point position of the air supply outlet should be about 30cm away from the air supply surface; 3.3.4 Consumption Eliminate the toxic agent against the opponent After poisoning, place the culture dish into the turntable, cover it with a porous sampling head cover, remove the protective cover, and open the planktonic bacteria sampler for sampling; After the sampling is completed, mark the culture dishes that have been sampled; After all sampling is completed, use the filter Gently spray the toxic agent onto the inner wall of the instrument cover and the turntable;3.3.7 When using culture dishes for testing, in order to avoid the impact caused by the transportation or handling of the culture dishes, negative control tests should be conducted simultaneously. One control dish should be taken from each time or area, and operated in the same way as the sampling dish but without exposing the sample. Then, it should be placed in the culture box together with the sampled culture dish for cultivation, and the results should be sterile. 3.4 Microbial sampling of workers' hands should be carried out according to the following steps:3.4.1 will be extinguished Mark the bacterial physiological saline tube properly;3.4.2 Consumption Eliminate the toxic agent against the opponent Poison, remove and extinguish Bacterial swab, open and extinguish Plug the bacterial physiological saline tube and immerse a cotton swab to extinguish it In bacterial physiological salt, after the cotton swab is soaked, lightly press it on the test tube wall several times and remove it Excessive moisture;3.4.3 Require the examinee to close their fingers together and immerse themselves in the solution Apply a cotton swab of bacterial physiological saline back and forth on the hand 10 times, covering the entire palm area;3.4.4 Remove the part of the cotton swab that comes into contact with the hand, and drop the cotton swab head in to extinguish it In the bacterial physiological saline tube, send for testing;3.4.5 After each pair of sampling points is sampled, apply cancellation The poison is eliminated by the opponent's scissors and hands Poison. After the sampling is completed, take another cotton swab and remove the part in contact with the hand. The cotton swab tip should be dropped into the swab to extinguish it Use a physiological saline tube as a negative control.3.5 Microbial sampling on the workbench should be carried out according to the following steps:3.5.1 Extinguish first Mark the bacterial physiological saline tube with the tag number corresponding to the worker's hand taken;3.5.2 The experimenter should wear sterile gloves and use disinfectant Poison should be disinfected by hand and positioning frame Poison, if necessary, burn the positioning frame with an alcohol lamp to accelerate the evaporation of alcohol;3.5.3 Select the sampling location and fix the positioning frame;3.5.4 Remove and extinguish Bacterial swab, open and extinguish Plug the bacterial physiological saline tube and immerse a cotton swab to extinguish it In bacterial physiological salt, after the cotton swab is soaked, lightly press it on the test tube wall and remove it Remove excessive moisture;3.5.5 Apply a cotton swab back and forth in the positioning frame 10 times;3.5.6 Remove the part of the cotton swab that comes into contact with the hand Remove the cotton swab head and wipe it out In the bacterial physiological saline tube, send for testing;3.5.7 After each sampling point is sampled, apply cancellation Eliminate the toxic opponent with a positioning frame and scissors Poison.After sampling, take another cotton swab and remove the part in contact with the hand Remove the cotton swab head and wipe it out Use a physiological saline tube as a negative control.3.6 Microbial testing after sampling3.6.1 For samples taken in a culture dish, invert the dish and incubate at 34 ± 1 ℃ for 24-48 hours, then count;For sampling with a sampling tube, sonicate the sampling tube in an ultrasonic cleaning machine for 5 minutes, mix well, and dilute the diluted solution to a 10 fold concentration on a clean workbench; Used to be extinguished Transfer 1ml of diluent into a sterile petri dish using a pipette, immediately pour the culture medium, mix well, and solidify. Pour 2 plates into each dilution, invert at 34 ± 1 ℃ for 24-48 hours, and count; 3.7 Result determination3.7.1 The bacterial count on the workbench should be ≤ 10cfu/cm2 (i.e. ≤ 250cfu/25cm2);3.7.2 The amount of bacteria on workers' hands should be ≤ 300cfu/hand;3.7.3 The number of settling bacteria at level 100000 should be ≤ 10 per dish;The concentration of planktonic bacteria at level 100000 should be ≤ 500 cells/m3 (≤ 125 cells/250L);

This article briefly discusses a widely concerned issue, the literature search problem in the clinical trial evaluation process of medical devices.It must be recognized that literature search needs to cover two types of data:Regarding medicine The clinical use of therapeutic equipment or its equivalent Bed dataData directly related to advanced technologies related to equipment and/or equivalent devices, benchmark devices, and similar devices and technologies, as well as medical services available for the intended patient population Data on treatment selection.If the manufacturer has their own equipment Bed data, this is a definite benefit. Literature and data can be reviewed together for consistent evaluation and comprehensive analysis.According to section MDCG2020-13D: "Clinical trial evaluation of medical devices should clearly state the selection criteria required by applicable regulations. CERs should distinguish between two types of data (the device being evaluated or equivalent, advanced technology, or alternative treatment options). If these data are unrelated to any of the above, provide the reasons for their inclusion.The purpose of literature search is to identify published scientific papers that are relevant to medicine The safety of medical equipment There are effective conclusions regarding the integrity, performance, clinical trial benefits of medical devices, and new equipment conditions. Literature retrieval should be accurately, thoroughly, and systematically documented.The selection of literature should be objective and reasonable, including all favorable and unfavorable information.Therefore, when considering writing a literature search plan, it should be kept in mind that the selected paper should reflect the intended use of the equipment.Literature search screening should include:Research questionThe database to be usedThe terminology to be usedInclusion/exclusion criteriaSearch methods for literatureHow to ensure data integrityHow to evaluate each data source and its correlation with the devices involvedHow to analyze and process dataFor more details on this, please refer to Appendix A5 in MEDDEV2.7/1Rev. 4.About the databaseBased on the research question and the type of evidence required, some databases can be selected.The revised Annex 4 of MEDDEV2.7/1 suggests establishing the following database:PubMed/Medicine: A solid baseline for initiating researchEMBASE: Provides information on medical practices used in Europe Complete information on medical equipment and therapyIn Cochrane Central Trial Registry: Provides complete information on European trialsMedline (PubMed) and EMBASE are leading The first literature database, Cochrane, is the primary choice for controlled trials.Regarding search termsThe search term is generally the product name or its indication, or a combination of both. However, a good approach is to combine them using logical operators. There are three main operators and, OR, and not, and using them allows you to combine search terms in a specific way to expand or shrink your results. Quotation marks and parentheses are also useful tools for improving the quality of the search process.Please always remember that the literature search protocol must be established correctly and well, as it constitutes a critical step The basis for other steps in the bed assessment process.Shenzhen Ruienni Medical Device Management Consulting Co., Ltd. can conduct systematic literature search and review in accordance with the MDR Regulation (EU) 2017/745. Our team can design a comprehensive literature search protocol and complete documentation for literature screening and data extraction processes. We can assist your new doctor The clinical application of therapeutic equipment is obtained from the perspective of literature Bed evidence to create documents that comply with MDR.