Central Service - Issue 3/2010
- What‘s New in Standardization: The Future of Standardization
- Sustained Developments in Reprocessing. 32nd French National Sterilisation Days in Lille, 28 and 29 April 2010
- IAHCSMM in Wonderland. 45th annual conference of the International Association of Healthcare Central Service Materiel Management in San Diego on 1 - 5 May 2010
Y. Uetera, Y. Saito, H. Yasuhara, N. Kumada, Y. Misawa:
Sterilizing Electronic Instruments for Neuronavigation Using the ”Prion Cycle" at 134 °C for 18 min in a Prevacuum Autoclave
In frameless stereotactic neuronavigation with optical sensors, surgeons use pointer probes, a type of electronic instrument, to correlate real anatomy in the operative field with image-based virtual reality. According to the manufacturer’s recommendations, our pointer probes should be sterilized at 134.0 °C for 18 minutes in a prevacuum autoclave, and these parameters should be validated in each hospital so that the pointer probes withstand at least 100 autoclaving cycles.
In our surgical center, the pointer probes are sterilized in a reusable rigid container using the prevacuum autoclave programmed at 135.0 °C for 20 minutes. Therefore, temperature and pressure were evaluated three times using wireless loggers in and outside the container simultaneously. The function of two brand new pointer probes was also evaluated after they had been sterilized 130 and 200 times, respectively.
Temperature and pressure data in the container were as follows: F0 value ranged from 622 to 649. Heat-up time (120.0 to 134.0 °C) ranged from 2 minutes 20 seconds to 2 minutes 30 seconds. Maximum temperature ranged from 136.1 to 136.3 °C. Holding time over 134.0 °C was 19 minutes 30 seconds, and cool-down time (134.0 to 120.0 °C) was 25 seconds, in each measurement. Temperature in the container equilibrated with the ambient temperature over a few hours. Vacuum level attained 50.1 to 109.8 mbar absolute during the vacuum pulses of air removal. Maximum pressure ranged 3243.5 to 3251.2 mbar absolute during sterilization. Vacuum level attained 70.5 to 161.0 mbar absolute during the vacuum pulses of the drying phase.
Both of the pointer probes functioned normally after they had been sterilized 130 times. However, both of them went out of order after they had been sterilized 200 times.
Thermometry revealed that time and temperature cycle of 134.0 °C for 18 minutes was satisfied in the container. The present results confirmed that the pointer probes could be autoclaved in our prevacuum autoclave using our method at least 100 times with a sufficient safety margin.
M.-T. Linner, A. Carter:
Responsibility for Reprocessing Medical Devices and Validation of Reprocessing Processes
Recommendations by the Quality Task Group (AK »Qualität«): Computer-Assisted Batch Documentation (Update of Recommendation 21 from Issue 2/2002)