Shelf Life of Stream Sterilzed Surgica Instruments Packaged in Linen-wraps Versus Plastic - Paper Bags
Sawet Srisir
Department of Surgery, Ramathibodi Hospital, Bangkok 10400, Thailand
In our institution surgical instruments are sterilized by steam stream sterilization (Aytoclave) wrapped in two layered linen packaging. Unused items must be re-sterilized every 2 weeks. However they has been recommendation in various textbooks. This method of sterilization has a reliable shelf life of 7 week. Meanwhile, it has been quoted that plastic -paper combination packaging of surgical instrument has an expired date of 1 year. For instruments that are seldom used, it is tempting to know whether sterilizing in linen versus plastic-paper packing in more cost effective.Objective: To compare the duration whereby surgical instruments remained sterile after autoclaving between two-layered linen packaging and disposable plastic-paper packing.Material and Method: Orthopedic screws were used in this experiment to represent surgical instrument. Seven hundred and thirty eight screws were divided into 3 groups. Group 1 consist of 360 screws which were individually wrapped in a two-layered linen packaging. Group 2 also consist of 360 screws individually contained in a disposable, heat-seated, plastic-paper bag. Group 3 was the control and consist of 18 screws which would not undergo any process of packing and sterilization. All specimens in Group 1 and 2 were sterilized simultaneously by steam sterilization. All specimens were kept on open-shelf in the operative room without special treatment. Twenty sterilized screws were take from each of group 1 and 2 for culture of both aerobic and anaerobic organisms every 2 weeks for the first 20 weeks and then every 4 weeks from the 20th to the 52th weeks. One non-sterilized screw in group 3 as also cultured at the same time.Result: From the day of sterilization up to the 52th week, not even a single screw in Group1 and 2 showed any growth of organisms in either aerobic and anaerobic cultures. On the other hand, all screws in group 3 which were bit sterilized, showed positive growth in aerobic culture.Conclusion: Small surgical instruments sterilized in two layered linen packaging as well as in disposable plastic paper bag could remain sterile for at least 52 weeks. Whether either of these two means of packaging could last any longer beyond this period of time was to be found out by further experimentation.
Archives of Gynecology & Obstetrics ปี 2542, พฤษภาคม ปีที่: 7 ฉบับที่ 8 หน้า