Adequate sterile supplies play an essential role in reducing the spread of diseases in the health service, so ensuring the correct cleaning cycle is vital
Author of Sterilization of Medical
Supplies by Steam, Volume 1
General Theory – third edition
about to be published
The publishers would like to thank
the World Forum for Hospital
All medical supplies, such as instruments, swabs and drapes, that are used on open wounds or in touch with the inner fluids of the body have to be sterile. Some are sterilised at the factory and are designed for single use, but many instruments and materials used for medical interventions are very expensive and are designed so that they can be re-used, making a reprocessing cycle necessary. Reprocessing should centralised in a single central sterile supply department (CSSD) serving
the whole facility. In mostly older health facilities sterilisation is still decentralised. Increasingly, the sterilisation activities of these departments are put under the responsibility of a single sterilisation professional in charge of sterile supply of the
In several countries, including France, a predisinfection step is required as soon as possible after use of the medical device. The objective is to reduce the bioburden and prevent proteins drying out. If the sterilisation department does not allow immediate treatment, which is often the case, the pre-disinfection takes place close to the location of use. The items are fully submerged after disassembly or opening for a defined period of time.
After that, the items are transported to the central sterilisation department for further treatment.
Many other countries employ mainly dry transportation of the dirty, used materials. This is possible because, in a modern sterilisation department, before cleaning, the instruments are hardly touched and they are transported very soon after use so that drying out is prevented. The weight for dry transport is lower, there is no danger of splashing and it is better for the environment.
After use, the soiled materials are collected and transported in suitable containers and trolleys to the location where the reprocessing takes place – the CSSD. Instruments and materials are taken to the cleaning section known as the ‘dirty area’ of the sterilisation department. Cleaning implies the removal of all visible debris and dirt. Most microorganisms, including any disease-causing agents, are removed. Adequate cleaning is the most essential step in the reprocessing cycle of sterile goods.
Inspection and tray assembly
It is essential that instrument trays for all procedures are complete and that each instrument works correctly. Each tray should be doublechecked to ensure it is complete. In order to prevent recontamination during storage, instruments and materials have to be packed. Packaging should allow for the sterilising agent to reach the actual load. After sterilisation,
packaging should prevent microorganisms from reaching the items inside and guarantee sterility up to the moment a product is used.
After packaging, microorganisms remaining after the cleaning process are killed in a steriliser and their number is reduced to a level that is considered safe: the Sterility Assurance Level. A range of methods are in use: moist heat; dry heat; ethylene
oxide; formaldehyde; irradiation and gasplasma. The most common and safe method used is moist heat using pressurised high-temperature steam in steam sterilisers or autoclaves. Sterilisers should meet the stringent technical standards for performance and safety – the European norm EN 285 for large steam sterilisers. To ensure the safety of the staff and patients, all processes in combination with each type of load in its packaging should be validated for each steriliser used for medical supplies – that is, you have to prove that your steriliser sterilises. Once the sterilisation cycle is completed, the goods are taken out of the steriliser. The cycle is checked according to the registered process data and indicators and, when the required conditions are met, the load is released for storage, transport and use. Sterile goods are stored in a dedicated area with special requirements for environmental conditions and stock management. A regime of product shelf-life or the concept of eventrelated sterility is used to ensure the integrity of each sterile item until its use. When sterile goods are needed, they are requested to be picked up from the sterile storage and are transported in dedicated closed trolleys or container systems to where they are needed. When materials are to be transported outside the facility, additional measures must be taken to ensure the integrity of the materials and an adequate protocol is necessary for handing over the goods to the end-user.
Use of sterile products
Any sterile product needs to be used correctly to ensure its safe use on a patient. Simply opening the sterile package incorrectly may contaminate instruments before they are used. Employing
aseptic procedures reduces the chances of recontamination at the moment of using sterile goods to a minimum. The aseptic opening of a sterile pack and the presentation of an instrument to the surgeon are examples of such procedures.
Each step in the sterile supply cycle is crucial to good and safe use of a sterile instrument or other item during a medical intervention. A mistake or failure in any of the steps may cause recontamination and makes the whole procedure useless.
It may result in huge costs, and can cause serious suffering and even endanger the life of patients and staff. That is why each step must be subject to vigorous monitoring realised through a quality assurance system. Each step in the cycle is analysed,
documented and monitored.