Infection Control: Cleaning and Disinfection Methods

Study Notes

Transmission of Micro-organisms

Environmental surfaces can be contaminated, posing a risk of transmitting infectious pathogens to patients.
Effective cleaning and disinfection practices are essential to break the chain of infection.

Disinfection Methods

Low-level disinfectants are effective against certain microbes but may not eliminate all pathogenic organisms.
High-level disinfectants (HLD) include:
- Boiling
- Moist heat at temperatures of 70-100°C
- Chemical agents such as Glutaraldehyde

Importance of Cleaning Prior to Disinfection

Surfaces must be cleaned to remove organic matter before applying disinfectants.
Cleaning reduces the microbial load and enhances the effectiveness of disinfection.

Mechanisms of Action for Chemical Disinfectants

Various disinfectants operate through different mechanisms:
- Disruption of lipid-containing cell membranes
- Modification of proteins

Cleaning and Disinfection Techniques

Instruments should be rinsed with purified water post-cleaning and dried with disposable paper towels.
Inspection of instruments is crucial to ensure all debris has been removed prior to disinfection.

Heat-Based Disinfection

Moist heat disinfection at 70°C-90°C effectively kills most non-sporing microorganisms.
Boiling is a method that ensures disinfection at 100°C, though not effective against bacterial spores.
Pasteurization is a mild heat treatment that eliminates harmful pathogens without achieving sterilization.

Chemical Disinfectants

Common chemical disinfectants include:
- Alcohol (70%) known for a wide spectrum of activity against bacteria, fungi, and many viruses but ineffective against spores.
- Quaternary Ammonium Compounds (QAC)
- Chlorine (e.g., hypochlorite), and iodine.

Precautions and Equipment

Protective gear such as gloves, masks, eyewear, and clothing should be worn during cleaning and disinfection.
Chemical disinfection is typically employed when heat treatment is impractical or likely to damage equipment.

Limitations of Disinfectants

Some disinfectants will not sterilize powders, ointments, or oils and should be used with caution to ensure effectiveness.

Description

Test your knowledge on the transmission of micro-organisms and the various cleaning and disinfection techniques required in healthcare settings. Understand the importance of cleaning before disinfection, the mechanisms of action for disinfectants, and the effectiveness of low and high-level disinfectants. This quiz is essential for anyone involved in infection control practices.