Desenvolvimento de um resistômetro a vapor para avaliação de indicadores biológicos e químicos à luz da norma iso 18472: 2018

Abstract

Most sterilizations of materials use heated steam as the sterilizing agent, and are performed in order to inactivate all microorganisms present on the surfaces of medical devices. Patient safety depends on instruments that are properly reprocessed. Sterilization is a process whose effectiveness cannot be verified by inspection or testing of the product, but by monitoring the performance of the process. In Brazil, it is instructed to use chemical indicators (QIs) and biological indicators (BIs) to monitor sterilization processes. Obtaining negative IB results and passing IQs makes it possible to develop a program that allows the release of the sterilized product based on them. ISO 11140 (2014) and ISO 11138 (2017) highlight the necessity to assess the performance compliance of IBs and IQs, for this, the use of a Biological indicator evaluation resistometer (BIER), better known as a resistometer, is required. Resistometers are test equipment designed to create accurate and repeatable sterilization environments, in which samples are almost instantaneously inserted into a sterilization condition and returned to ambient conditions. In view of this, the Clean Up Biotecnologia Ltda. industry, located in Campo Mourão, Paraná, brought the need to build a BIER for monitoring its products, solving an internal demand through an existing solution, having a local innovation, which is also known as incremental. This work aims to develop the steam resistometer for validation of products used for monitoring steam sterilization, chemical and biological indicators, in light of the ISO 18472:2018 standard. The methodology of the work goes through the interpretation of the standards involved and the fulfillment of all the established requirements, united to the characteristics stipulated by Clean up, develop a partnership with a company specialized in the area of autoclaves, for being a similar product, which will assist in the assembly and manufacture of the equipment, and finally, validate the BIER through the verification of a routine cycle in compliance with the established requirements. The results showed compliance of requirements such as cycle heating time and temperature stabilization during the sterilization plateau, obtaining a heating ramp to 121 °C in only 9 seconds, besides a permitted variation of 0.5 °C during the sterilization plateau of a 134 °C cycle. It is noteworthy the need to perform a heating cycle before a test cycle to avoid failures in the stipulated parameters. It was concluded that it was possible to develop and build a resistometer that meets all the requirements determined by the ISO 18472:2018 standard, also obtaining a leak rate of 0.6 mBar/min from the Leak Test, as well as meeting the characteristics desired by the Clean up Brazil company interested in the project.