The importance of effective disinfection of medical devices in clinics and hospitals

According to the World Health Organization (WHO), hundreds of millions of people worldwide are affected each year by avoidable infections within the healthcare system (healthcare-associated infections). An unjustifiably high number of infections are due to the handling of contaminated medical equipment and devices. These devices are vital for saving patients' lives and protecting hospital staff, but it is also essential that sanitation equipment and procedures are implemented to ensure they are safely cleaned and disinfected after use.

What does medical device disinfection consist of?

Before detailing the medical device disinfection process, general principles of cleaning and disinfection and some key definitions must be clarified. The World Health Organization describes the decontamination and reprocessing of medical devices, where the decontamination process is divided into three levels: cleaning, disinfection, and sterilization.

1. Cleaning

Cleaning is the first stage and involves the removal of infectious biological material, dust, and soil from a surface that needs to be disinfected. This is carried out manually or mechanically, using water with detergents or enzymatic products. After the physical material is removed, the second stage is disinfection.

2. Disinfection

Disinfection is the process of removing disease-causing organisms to make medical equipment safe for use. An example would be placing medical instruments in a washer, i.e., sterilization. By definition, disinfection suggests the use of a professional disinfectant product that inactivates almost all disease-producing microorganisms. In some cases, however, the same reduction in the level of microbial contamination as sterilization, the next stage, might not be achieved.

3. Sterilization

Sterilization is a process used to render an object free of microorganisms, including viruses and bacterial spores. Since not all patient-care items require sterilization, responsible hospital staff must identify, based on the intended use of the items, whether cleaning, disinfection, or sterilization is required.

What is the difference between disinfection and sterilization?

Disinfection removes most germs, but sterilization eliminates all good and bad microorganisms. Sterilization is very common in medical environments, while disinfection can take place in households, public institutions, schools, or other spaces with high foot traffic.

As mentioned, the process of decontaminating medical instruments and devices plays a very important role in preventing nosocomial infections. Faulty sterilization of surgical instruments and ineffective disinfection of reusable devices and objects, such as endoscopic, respiratory, and transport devices, leads to infections among patients, medical staff, and visitors.

The problems that most frequently arise due to inadequate decontamination procedures or harmful device reuse practices are surgical site infections, HIV, hepatitis B and C infections, and catheter-associated urinary and vascular infections.

Given the recent threats caused by Coronavirus pandemics, awareness regarding the spread of viral pathogens is increasing and is being followed by increased attention to infection prevention and control procedures and the improvement of medical practices.

What are the characteristics of an effective disinfectant?

According to WHO guidelines regarding decontamination, there are several points that an ideal disinfectant must meet, namely:

• High germicidal activity,
• Ability to rapidly destroy a wide range of microorganisms, including spores,
• Chemically stable,
• Effective in the presence of organic compounds,
• Compatible with the surface being disinfected,
• Ability to penetrate into crevices (desirable).

Professional disinfectants approved by the Ministry of Health

Types of chemical disinfectants

1. Alcohol

Even though it is accessible and widespread, alcohol is not recommended for sterilizing medical and surgical materials because it is not sporicidal. However, alcohol could occasionally be used for disinfecting external surfaces of equipment, such as ventilators and manual ventilation bags, ultrasound instruments, CPR manikins, or medication preparation areas. In healthcare settings, alcohol (ethanol or propanol) is commonly used in 60%-70% concentrations.

2. Chlorine and chlorine compounds

Hypochlorites are widely used in healthcare facilities in a variety of contexts: for spot disinfection of countertops and floors, as well as for disinfecting tonometer heads, linens, and dental appliances. In addition, they can be used for decontaminating blood spills and CPR training manikins.

The most common variant of chlorine – a full-strength bleach was recommended for self-disinfecting needles and syringes when there are no conditions to purchase new ones. Furthermore, chlorine has been used as a disinfectant in water treatments. It is important to mention that when using a chlorine-releasing agent, it is necessary to take care with metals and plastic, as chlorine is corrosive. KLINTENSIV® Fizzy Tablet – Chlorine-based disinfectant

3. Formaldehyde

Formaldehyde is used as a disinfectant and sterilant in both liquid and gaseous states. It is a high-level disinfectant, which means it is capable of completely eliminating all microorganisms, except for a small number of bacterial spores.

However, the uses of formaldehyde in healthcare are limited due to its irritating vapors and smell. The limitation consists of the link found between formaldehyde and nasal and lung cancer. Formaldehyde is also used for the preparation of viral vaccines (poliovirus and influenza), as an embalming agent, and, historically, it was used for sterilizing surgical instruments, usually mixed with ethanol.

4. Hydrogen peroxide

Hydrogen peroxide is active against a wide range of microorganisms, including bacteria, yeasts, fungi, viruses, and spores. Under normal conditions and when stored properly, hydrogen peroxide is extremely stable.

Commercially available 3% hydrogen peroxide is a stable and effective disinfectant for use on inanimate surfaces. It has also been used in concentrations from 3% to 6% for disinfecting soft contact lenses, ventilators, fabrics, and endoscopes, and has been proven effective in spot disinfection of fabrics in patient rooms. PEROKLIN® – Hydrogen peroxide-based disinfectant

5. Peracetic acid

Peracetic acid is an oxidizing agent that acts in a similar way to hydrogen peroxide. The most important advantages of peracetic acid are: it has no harmful decomposition products (acetic acid, water, oxygen, hydrogen peroxide), it is effective in the presence of organic matter, it has been proven to improve the removal of organic matter, and it leaves no residue. It is used in automated machines for the chemical sterilization of medical (endoscopes, arthroscopes), dental, and surgical instruments. High-level concentrated disinfectant