Medical textile performance testing

In response to ever-increasing innovation and development of medical textiles, medical textile performance testing is required during the manufacturing process. The test requirements developed by the European Medical Devices Directive are presented in this section. There are different classes of test methods and standards. However, the conformity with each test standard depends on the types and classes of the medical... 

Hence this chapter mainly explains the medical textiles performance testing methods recommended in part 2 of EN 13795 e.g. 

The requirement and importance of medical textiles performance testing for the healthcare staff and the medical textile industry... 

Last, but not least, standards are needed for documentation of the performance and safety of these new products by setting up new test procedures. A step in this direction was done by the European Committee for Standardization to create a working group around smart textiles. Hopefully, more initiatives in this vein will be started in the near future to enhance the smart medical textile market. 

Medical textiles are classified in Scheme 6.1. This scheme detailing constituents of various polymeric substances (eg, natural or synthetic) and their construction processes as outlined in the previous section is important in defining medical textiles aptly. Similarly, testing the properties and performance of medical textiles with suitable methods under accredited standards is essential. Thus, it is worthwhile to adequately describe all test methods, performance testing features, results analysis, and presentation guidelines of test results prior to marketing and commercialization of a device or product. This is done so that care and quality assurance of medical textiles will be documented appropriately, which benefits users. 

There are many ways textiles can be contaminated, due to their uses and/or through their environment. Potential threats include germs and fungi. However, there are a number of antimicrobial and antifungal medical textiles available nowadays. Antimicrobial performance testing using appropriate standard methods, test results, validation, and documentation is important. These tests are described in the foUowing section. 

When the medical textile or part of it is considered as the medical device, then its toxicity performance testing requires validating under the ISO 10993 test standard. The fabric or parts of it are put in either direct or indirect contact with the cell culture system (eg, L929 cell Une), and then the cell viability resrrlts determine the release of toxic materials from the tested fabric or device. 

Furthennore, some materials, including medical textiles, have the potential to cause allergy or irritation. The sensitization potential of the material is therefore required to be tested. The ISO 10993-10 assesses the possible contact hazards from chemicals released from the devices, which may produce skin, mucosal, or eye irritation and skin sensitization. Currently, there has been no satisfactory in vitro test to eliminate the requirement for in vivo testing to evaluate irritation. However, the rat skin Transcutaneous Electrical Resistance (TER) test and the human skin model test have been internationally validated and accepted as alternative tests to assess the skin corrosion with chemicals (OECD, 2009a,b). To perform the test, an animal (rabbit) with the healthy intact skin needs to be used and the fur on the back of animal is clipped 24-4h of testing with approximate size of 10cmX 15 cm and then 0.5g or 0.5 mL of materials apply to the site and then the application site is covered with... 

From a scientific point of view, medical textiles are located at the interfaces between technical disciplines and life sciences. On the one hand, the technical aspect concerns textile engineering, material chemistry, process control, testing and certification, etc., which are needed for the manufacture of high-quality medical textile products. On the other hand, life sciences such as medicine, microbiology, and other related subjects are required for the development of functional performances of these products. In practice, the different scientific and technical disciplines interact and overlap with one another, with new developments in any one of these branches able to generate new innovations in others. For example, new superabsorbent and gel-forming substances invented in chemistry have been applied in the development of new baby diapers and adult incontinence products. 

Biocompatibility is defined as a measurement of how compatible a material or a device is with a biological system. With medical textile products, the purpose of performing biocompatibility testing is to determine their fimess for human use, and to see whether their use can have any potentially harmful physiological effects. In this respect, medical textile products share the same requirement for biocompatibility as medical devices. 

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