With the exception of bacterial spores, disinfection refers to a method that gets rid of the majority of pathogen-causing germs. Liquid disinfectants or moist pasteurisation are frequently utilised in OT environments and for anaesthetic equipment. High Level Disinfection (HLD) is a technique that eliminates vegetative bacteria, viruses, and fungus but not necessarily bacterial spores. For this, disinfectants like aldehydes, peracetic acid, and chlorine dioxide are utilised, and prolonged contact times with these substances may result in sterilization [1].

All harmful vegetative bacteria, including Mycobacterium tuberculosis, fungi, and the majority of viruses are destroyed by intermediate level disinfection (ILD), with the exception of a few tiny viruses without envelopes and bacterial spores. Iodophors, phenols, sodium hypochlorite, and alcohol are frequently used to treat ILD.

With the exception of M. tuberculosis and endospores, low level disinfection (LLD) kills some fungi, some viruses, and the majority of vegetative bacteria. For LLD, disinfectants such alcohol and quaternary ammonium compounds are frequently utilised.

Based on the level of infection risk, Spaulding created a simple and logical classification system in 1968 to specify how medical equipment should be cleaned and sterilised. This system is still employed by several nations in their sterilisation and disinfection regulations. 

Critical Items 

This category includes things that are inserted into the circulatory system or any other sterile body cavity and represent a high risk of infection if contaminated. The needles in this category, which also includes catheters, should be sterilised before being used again [2].

Semi Critical Items

This group includes substances that come into touch with mucous membranes and skin that is not intact but do not penetrate either or pass the blood-brain barrier. This category includes items like connectors, laryngoscopes, laryngoscope blades, endoscopes, endotracheal tubes, esophageal stethoscopes, resuscitation bags, face masks, and oral and nasal airways. These materials should be as sanitary as possible because undamaged mucous membranes are prone to germs, bacilli, and viruses. High-level disinfection is permissible, though. To avoid contamination, these things should be kept in a clean environment [3].

Non-Critical Items

This category includes anything that comes in contact with healthy skin, such as blood pressure cuffs, arm boards, stethoscopes, pulse oximeter sensors, head straps, EKG electrodes, all accompanying cables, etc. These goods should be cleansed and given intermediate or low-level disinfection because skin acts as a good barrier to the majority of bacteria [4].        

Environmental Surfaces

This category was specifically included to include objects or surfaces that could potentially host organisms that people working in the OT environment could potentially convey. Surfaces of medical equipment, laryngoscope handles, infusion pumps, equipment carts, anaesthesia carts, monitor knobs, blood warmers, monitoring cables, and other equipment not in direct patient touch are included. The appropriate method of decontamination for this group is intermediate or low level disinfection [5]. Inorder to reduce the risk of HCAIs, operating rooms and related spaces, such as the one used for equipment sterilisation, should be built and maintained to the criteria specified by the established guidelines [6].

Since every patient has potential pathogens in their respiratory system, it is imperative to take the proper precautions to prevent cross-infections between patients and between patients and anesthesiologists.

Potential transmission routes for nosocomial infections through an anesthetist's hand include anaesthesia machines and equipment [7]. Therefore, every surface of the anaesthesia machine, especially the knobs and the monitor, needs to be cleaned every day, often at the conclusion of the workday or right away if it is contaminated, using a suitable intermediate or low level disinfectant. Items that will be utilised should be set up on tidy surfaces before the following case.

Along with the ventilator and CO₂ absorber, the breathing circuit also connects the patient's respiratory system directly to the machine.

The breathing circuits are lengthy, wavy, and challenging to maintain. If a filter is inserted between the endotracheal tube and the Y piece after sterilisation or high level disinfection, they can be used again [8]. If accessible, ultrasonic cleaning is a good choice. Filters work better at stopping the spread of bacteria than viruses. However, it is recommended that bellows, unidirectional valves, and carbon dioxide absorbers be frequently cleaned and sanitised. Every time the absorbent is changed, the canister needs to be cleaned. According to the manufacturer's recommendations, the canister should be cleaned and disinfected [9].

Reusable face masks that have become contaminated should be cleaned, thoroughly rinsed, dried, and then sterilised or treated to high level disinfection while taking care not to harm the pneumatic cushion.

Suction catheters, connectors, and endotracheal tubes are frequently provided sterile and intended for single patient use. Endotracheal tubes, connectors, suction catheters, and airways that are reusable should all be sterilised and cleansed after each use. Suction catheters can be used on the same patient for up to 24 hours if they are properly cleansed and kept.

Supraglottic airways that are made to be used repeatedly ought to be removed, cleaned, immersed in enzymatic detergent, and then autoclaved. These should only be sterilised as often as the manufacturer specifies. Reusing a supraglottic airway after tonsillectomy or adenoidectomy is not advised.

Reusable gum elastic boughs should be well cleaned and sterilised or disinfected. Laryngoscope blade cleaning and decontamination procedures that are commonly used between patients are typically unsuccessful, leaving lingering pollutants near light sources [10]. After quickly cleaning the blade with an enzymatic detergent, it should ideally go through a high level of sterilisation or disinfection. Laryngoscope blades and grips are frequently contaminated, according to numerous studies [11]. Most of us frequently forget that laryngoscope knurled handles can also become infected. After each usage, handles should be cleaned, sanitised, and, if necessary, sterilised. In order to avoid contaminating surfaces and drapes, anesthesiologists should always wear gloves during intubation. Laryngoscopes and bronchoscopes made of fiber-optic technology should be thoroughly cleaned, rinsed with water, and disinfected. An automated system is the most effective way to disinfect these. If there are instructions for maintaining these instruments, they should be followed [12].

If an automatic reprocessor is available, transesophageal echocardiography probes should be meticulously cleaned, disinfected, and sterilised.

For all of the equipment, there should be regular cleaning and disinfection procedures that follow the manufacturer's instructions. National standards for the sterilisation and disinfection of equipment in operating rooms and intensive care units are required. Anaesthetists and hospital administrators should closely supervise sterilising procedures in order to ensure compliance with the requirements while also safeguarding themselves.

1. Rutala, W.A. et al. "Disinfection and sterilization: an overview." Am. J. Infect. Control., vol. 41, no. Suppl 5, 2013, pp. S2–5.

2. Rutala, W.A. et al. "Disinfection and sterilization in health care facilities: what clinicians need to know." Clin. Infect. Dis., vol. 39, 2004, pp. 702–9.

3. Canadian Standards Association. "Decontamination of reusable medical devices." 2008. Accessed 3 July 2022, pp. 1–87.

4. Rutala, W.A. et al. "Guideline for disinfection and sterilization in healthcare facilities." HICPAC, 2008.

5. British Columbia Patient Safety Branch Ministry of Health. "Best practice guidelines for the cleaning, disinfection and sterilization of medical devices in health authorities." 2007.

6. Patwardhan, N. et al. "Disinfection, sterilization and operation theater guidelines for dermatosurgical practitioners in India." Indian J. Dermatol. Venereol. Leprol., 2011, pp. 83–93.

7. Boyce, J.M. et al. "Guideline for hand hygiene in health-care settings: recommendations of the Healthcare Infection Control Practices Advisory Committee and the HICPAC/SHEA/APIC/IDSA Hand Hygiene Task Force." MMWR Recomm. Rep., 2002, pp. 1–45.

8. American Association of Nurse Anesthetists. "Infection control guide for certified registered nurse anesthetists." 2012.

9. Spertini, V. et al. "Bacterial contamination of anesthesia machines’ internal breathing-circuit-systems." GMS Krankenhhyg Interdiszip., 2011, Doc14.

10. Call, T.R. et al. "Nosocomial contamination of laryngoscope handles: challenging current guidelines." Anesth. Analg., vol. 109, 2009, pp. 479–83.

11. Muscarella, L.F. "Recommendations to resolve inconsistent guidelines for the reprocessing of sheathed and unsheathed rigid laryngoscopes." Infect. Control Hosp. Epidemiol., vol. 28, 2007, pp. 504–7.

12. Howell, V. et al. "Chlorhexidine to maintain cleanliness of laryngoscope handles: an audit and laboratory study." Eur. J. Anaesthesiol., vol. 30, 2013, pp. 216–21.