5.14: Cleaning, Sterilization, and Disinfection
Cleaning, disinfection, and sterilization are the methods that help to break the infection chain and prevent disease.
Cleaning
The cleaning process usually involves using water with detergents or enzymatic cleaner and removing foreign material from objects and surfaces, including organic material such as body fluids or inorganic material like soil. Cleaning is performed before high-level disinfection and sterilization because foreign materials on the cover of the devices interfere with process efficacy.
The procedure of cleaning
Rinse the contaminated object under running water to remove organic material. Once rinsed, wash the object with soap and warm water, and then rinse the object thoroughly. To remove debris or dirt in seams or grooves, use a brush. Open hinged items for cleaning, and then rinse again in warm water. Depending on the classification of the item, dry it and prepare it for sterilization or disinfection. After cleaning the object, the brush, gloves, and sink used are considered contaminated and are washed and dried according to policy.
Disinfection
Disinfection is a process that eliminates several microorganisms, except bacterial spores, from inanimate objects. There are two types of disinfection: the disinfection of surfaces and high-level disinfection. High-level disinfection is required for some patient care items, such as endoscopes and bronchoscopes. Chemical sterilants disinfect surfaces and are known to kill spores after prolonged exposure (3-12 hours). At comparable concentrations, disinfectants will kill all microorganisms except many bacterial spores. However, shorter exposure times (e.g., 20 minutes for 2% glutaraldehyde) are sometimes appropriate. High-level disinfectants destroy most vegetative bacteria and some fungi and viruses, while low-level disinfectants kill the microbes in about 10 minutes.
Sterilization:
Sterilization eliminates all germs and spores found on the surface of an item or in a fluid. Sterilization methods include processing items using steam, dry heat, hydrogen peroxide plasma, or ethylene oxide (ETO). The decision to clean, disinfect, or sterilize a contaminated item is influenced by its intended use. Sterilization destroys all microorganisms on an item's surface to prevent disease transmission associated with its use. The categories for the disinfection and sterilization processes include critical, semicritical, and non-critical items.
- • Critical Items: Items entering tissue or the vascular system are critical or essential items as they pose a high risk of infection when contaminated with microorganisms, especially bacterial spores. Essential items must be sterile. These items include surgical instruments, cardiac or intravascular catheters, urinary catheters, and implants.
- • Semicritical Items: Items that come into contact with mucous membranes or nonintact skin also present a risk known as semicritical items. These objects must be free of all microorganisms. Semicritical items must be high-level disinfected (HLD) or sterilized. Semicritical items include respiratory and anesthesia equipment, endoscopes, endotracheal tubes, GI endoscopes, and diaphragm fitting rings.
- • Non-critical items: Items that come into contact with intact skin are considered non-critical and need to undergo low-level disinfection. This is because intact skin is a reliable barrier to most germs. A few examples of non-critical items are bedpans, blood pressure cuffs, crutches, bed rails, linens and patient furnishings.
