New Low Temperature Sterilization Processes

Abstract

➜ THERMOLABILE MD can only be sterilized with low-temperature processes. ➜ LOW-TEMPERATURE PROCESSES used in the medical setting. Hydrogen peroxide sterilization | 1 Introduction For medical device (MD) reprocessing there are various processes that must be taken into account. The continuous, rapid pace of developments in medical technology is driving the introduction of ever more complex systems and medical devices, which in turn make increasingly more stringent demands on reprocessing. For example, there is a sharp rise in the number of ➜ THERMOLABILE (heat-sensitive) MDs, such as flexible endoscopes, camera heads, ultrasonic transducers and electronic sensors, which can only be sterilized with low-temperature processes. Even the preceding cleaning and disinfection steps are carried out at lower temperatures for the material compatibility reasons mentioned. Instead of the normally used thermal disinfection (e.g. A 0 3000-at around 90 °C), chemothermal disinfection (ad-dition of a disinfectant) is employed at temperatures of generally less than 60 °C. Likewise, instead of the generally more popular steam sterilization process at temperatures of 134 °C, for sterilization of heat-sensitive medical devices low-temperature sterilization at much lower temperatures (e.g. 50-70 °C) is used. In the medical setting in Germany, Austria and Switzerland the following ➜ LOW-TEMPERATURE PROCESSES are employed:-Hydrogen peroxide sterilization with and without a plasma phase-Low-temperature steam and formaldehyde sterilization (LTSF)-Ethylene oxide sterilization-Gamma irradiation (industrial production) If necessary, prionicidal activity must be taken into consideration. The KRINKO/BfArM Recommendation* 2012, Annex 7, sets out measures to curtail the risk of transmission of CJD/vCJD via medical devices. Other factors, e.g. cycle times, chamber volume, sterilization temperature, running costs (such as maintenance and validation) and energy costs, should be taken into account at the time of procurement. | 2 Processes 2.1 Hydrogen peroxide sterilization with and without a plasma phase Hydrogen peroxide sterilization is a low-temperature sterilization process with activity in temperature ranges below 60 °C. Most sterilizers operate at a temperature of around 50 °C-55 °C. The cycle times chosen will depend on the respective system (sterilizer model and design) as well as on the design of the MD (lumen, length, materials). The information supplied by the sterilizer manufacturer and the reprocessing instructions for the specific medical device must be observed. Instrument compatibility with the sterilization process and intended programme must be evaluated and a written record of that kept. Partial prionicidal activity has been demonstrated for a number of processes (see also the aforementioned KRINKO/BfArM Recommendation, Annex 7).