Central Service - Issue 5/03

EDITORIAL

Competence and Personnel Qualification

NEWS UPDATE

What's New in Standardisation: Chemical Indicators and LTSF Sterilizers
Sterilization and Reuse Course Report, Izmir, Turkey
Achieving the Impossible. Report on the DGSV Annual Congress, 2 - 4 October, Tübingen
Report on Experiences with the European Medical Devices Directive

MAIN ARTICLES

A. C. P. de Bruijn, A. W. van Drongelen:
The Relevance of the Bowie and Dick Test in Hospital Sterilisation
(Zentr Steril 2003; 11 (5): 319-328.)

Abstract
Steam sterilisers are routinely subjected to a series of tests. Typically this includes an annual performance qualification (including temperature measurements in an empty steriliser chamber and in the Bowie and Dick test pack), weekly air leakage test, daily Bowie and Dick test and chemical indicators per batch.

Years ago this series of tests was particularly useful. The sterilisers were manually controlled or were fitted with mechanical semi-automatic controllers, which lacked the necessary reliability. Failure of valves and seals occurred frequently. Steam supply for the sterilisers was seldom dedicated. Sterilisers were simply hooked up to the main steam supply and interference from concurrent operated autoclaves or other applications, such as the kitchen or heating, were taken for granted.

Equipment and procedures have evolved and time has come to ask whether the classic Bowie and Dick test is still necessary or even useful.

M. Pfeifer:
The Kinetics of Protein Detachment in Alkaline Cleaning. Calculating the Cleaning Performance ROH-
(Zentr Steril 2003; 11 (5): 329-338.)

Abstract
The cleaning performance of alkaline detergents depends, as well as on the cleaning time, on the cleaning temperature and the pH value reached. On the basis of theoretical approaches and the proof furnished by the following kinetics tests, it has been possible to work out a formula for calculating the cleaning performance. Armed with this, errors can be avoided in programme settings and dosage of alkaline detergents, and programme parameters can be tailored to specific cleaning problems.

J. Huys, P. Mwalilino:
Implementation of Courses for Operators and Engineers on Sterilization of Medical Supplies. Lilongwe Central Hospital, Lilongwe, Malawi; March 24 - April 4, 2003

DISCUSSION

K.-H. Annecke:
Cleaning and Disinfection of Flexible Endoscopes in Washer-Disinfectors
(Zentr Steril 2003; 11 (5): 344-348.)

Abstract
Automated processing of flexible endoscopes is the only way to reproducibly carry out cleaning and disinfection with validated processes. Manual processing with comparative technical parameters (liquid quantities, etc.) calls for considerable greater time investment. If channel patency is assured by manual pretreatment as per the RK guideline, the processes currently available on the market are equivalent regardless of their underlying technical principles provided that the washer-disinfectors are properly operated. Individual manufacturers can confirm this by issuing an expert opinion.

If manual pretreatment is not carried out, the washer-disinfector should be capable of detecting channel blockages greater than 20%, because the latter can impede complete cleaning. The washer-disinfectors currently available on the market are able to detect only a higher level of channel blockage or, alternatively, they try to eliminate these by using pressure values that are higher than the limit values specified by the endoscope manufacturers. The machines of the future will be able to use methods capable of detecting channel blockages as low as 10%, thus possibly obviating the need for pretreatment to ensure that channels are not blocked.

STERILIZATION BASICS

P. Hooper:
Operational Procedures in the SSD

RECOMMENDATIONS BY THE QUALITY TASK GROUP (AK »QUALITÄT«)

Packaging Systems - Part 2: Hard Packaging
Classifying Medical Devices before Processing (as of October 2003)