The use of disposable or single-use equipment is becoming more popular in the west as a solution to this issue, but it is not practical in a nation like ours. The largest disadvantages would be the financial strain of maintaining a huge inventory on the institutions, the greater expenses to the patients and the growing burden on the authorities for waste management. Thus, we are essentially left with no alternative but to continue using reusable equipment while adhering to decontamination procedures and taking the necessary infection control precautions in accordance with the norms and recommendations established by the hospital authorities [1].

Despite several advancements in the development of antimicrobial drugs and sterilise techniques, their efficiency is still influenced by a number of conditions. To select the one that is most appropriate for the task, we must have a complete understanding of these agents, procedures and how microorganisms react to them. Evidence-based recommendations are available as guidelines for disinfection and sterilisation in healthcare facilities. These recommendations include the preferred methods for cleaning, disinfection and sterilisation of patient-care medical devices as well as for cleaning and disinfecting the Operation Theatre (OT) [2].

A technique known as sterilisation ensures an appropriate level of sterility by destroying or eliminating all microbial life, including bacterial spores. Some techniques that can be used for this include steam under pressure, dry heat, Ethylene Oxide (ETO) gas and hydrogen peroxide gas plasma.

Sterilization via Chemical Agents

This quick and simple procedure is appropriate for equipment that is susceptible to heat sterilisation damage. Depending on the type of item that needs to be disinfected or sterilised, equipment must be totally submerged in a disinfectant-containing solution for a variety of times. The item's exposed surfaces are where the sterilant works. For endoscopes, this kind of sterilising is frequently utilised.

In order to produce a high level of disinfection in 20 to 30 minutes, glutaraldehyde-based solutions are frequently utilised. However, their sporicidal efficacy may take 3 to 10 hours of exposure time [3]. While activated glutaraldehyde has a 14-day shelf life, its phenol-containing formulations have a 28-day shelf life [4]. Orthophthaldehyde doesn't need to be activated and can disinfect at a high level more quickly than glutaraldehyde in a shorter amount of time. It can be disposed of down the drain without a neutralizer and has fewer adverse effects [5].

Iodine and a solubilizing agent are combined to form an iodine compound or iodophor, which releases free iodine in aqueous solution. Iodophors only destroy bacteria; they have no effect on spores or tiny hydrophilic viruses.

Because they are ineffective against bacterial spores, M. tuberculosis and some fungi, iodophores are primarily employed as antiseptics and are no longer used as high-level disinfectants.

Alcohols work best when concentrated between 70% and 90% by volume. They need to be moist for at least five minutes in order to disinfect [6]. Alcohol cleaning is a simple kind of disinfection. Hepatitis B Virus (HBV) inactivation takes place in 15 minutes while HIV inactivation takes place in 1 minute thanks to the powerful bactericidal properties of ethanol. Isopropyl alcohol works just as well against bacteria as it does against lipid-containing enteroviruses. For cleaning fiberoptic cable outside surfaces, alcohol is frequently utilised [7].

Phenols are regarded as low-level to moderate disinfectants.

Even after complete cleaning, they may still be released and irritate tissues because they are absorbed by porous surfaces. 3 percent phenolics had no effect on M. tuberculosis, certain fungi or bacterial spores. Their application is limited to non-critical equipment and environmental surfaces [8].

In general, quaternary ammonium compounds (quats) do not have sporicidal, tuberculocidal or virucidal properties. For low-level disinfection, they are employed. They are fine for use on noncritical surfaces, however endoscope decontamination is not advised. They are commonly employed in everyday environmental sanitation of walls, furniture and floors.

Peracetic or peroxyacetic acid, is a powerful disinfectant that acts quickly against all germs and is sporicidal even at low temperatures. It doesn't generate any negative byproducts of breakdown. Its effectiveness is not diminished by the presence of biological materials. Up to 14 days can be spent using a formulation with about 1 percent hydrogen peroxide and 0.08 percent peracetic acid. This diluted solution has a corrosive impact on ocular tissue but does not irritate the skin.

The most often used chlorine disinfectants are hypochlorites, which come in liquid (e.g., sodium hypochlorite) and solid (e.g., calcium hypochlorite) forms. They are affordable, fast-acting, broad-spectrum microbicidals that leave no harmful aftereffects. All chlorine-releasing chemicals' disinfection potency is measured in ppm (parts per million), where 1 mg/litre equals 1 ppm or 0.0001 percent. HBV at 500 ppm and HIV at 50 ppm are both rendered inactive within 10 minutes. It does not kill spores but is tuberculocidal at no less than 1000 ppm [2].

The antibacterial, virucidal, sporicidal and fungicidal activities of hydrogen peroxide are well known. It takes hours to get rid of spores, even if the majority of microbiological forms are eliminated in less than an hour. It needs to be shielded from light and kept in a cool environment. A 7.5 percent solution can disinfect at a high level in 30 minutes, whereas a 3 percent solution disinfects at a low level and is suitable for inanimate surfaces. Metals corrode at higher concentrations. It is being utilised in conjunction with a nebulizer system to clean the operation room [9].

Both a disinfectant and a sterilant, formaldehyde was utilised in its liquid and gaseous stages. However, even at very low levels, its offensive odour and irritating fumes prevented widespread use. Despite being a powerful disinfectant, it is no longer employed in the majority of hospitals due to its potential function as a human carcinogen. Formalin is the name for the formaldehyde solution that is accessible.

A hazardous gas that is colourless, combustible and explosive is called Ethylene Oxide (ETO). Four key factors-gas concentration, temperature, humidity and exposure time-have an impact on the efficiency of ETO sterilisation. The exposure duration can be shortened by raising the temperature, with a total cycle time of 3 to 6 h, sometimes even 12 h. ETO is absorbed by some of the things in various amounts when it comes into touch with them. Mechanical aeration for 8 to 12 hours at 50 to 60 ° C will degas the hazardous ETO residue from exposed items. The prolonged cycle time, high cost and exposure risks are the main drawbacks of ETO [10]. Eye pain, a sore throat, a headache, nausea, vomiting, dyspnea, cutaneous irritation or burns are symptoms linked to ETO exposure. Additionally, it has been shown to be carcinogenic. To reduce exposure, one must heed the correct advice [11].

Gamma radiation is a safe, non-harmful procedure that does not impact the environment or the goods that are exposed. Items are exposed to gamma rays using this procedure at a dose level that is typically employed. As long as the packing is intact, the items' sterility is maintained indefinitely. The tremendous penetrating ability of gamma radiation makes it possible to sterilise equipment of any shape. This technique can also be used to sterilise thermo labile materials [11].

The fourth state of matter has been referred to as gas plasmas. The electric field generates a gas plasma. A deep vacuum is created to allow for the greatest possible hydrogen peroxide vapour dispersion over the equipment, which also helps to reduce the need for excessive heat. Water and oxygen are the end products and no hazardous compounds are produced. This technique works well to sterilise glass objects, Plastics, Polyvinyl Chloride (PVC), metal objects, cables made of electric and fibre optics and rigid endoscopes, but it is ineffective for cellulosic materials like linen, cotton and paper. Equipment can be utilised right away because the cycle doesn't need to be aerated [12].

Patients with potentially harmful organisms are cared for by anaesthetists. Despite having a sufficient understanding of nosocomial infection, hand hygiene, decontamination and equipment sterilisation are frequently neglected in anaesthetic settings where various and complex tasks and procedures must be performed quickly.

1. Association of Anaesthetists of Great Britain and Ireland. “Guidelines-Infection Control in Anaesthesia.” Anaesthesia vol. 63, 2008, pp. 1027–1036.

2. Rutala, W.A. and Weber, D.J. Guideline for Disinfection and Sterilization in Healthcare Facilities. Healthcare Infection Control Practices Advisory Committee (HICPAC), 2008.

3. Barbosa, J.M. et al. “Endoscope Reprocessing Using Glutaraldehyde in Endoscopy Services of Goiânia, Brazil: A Realidade em Serviços de Endoscopia de Goiânia, GO.” Arquivos de Gastroenterologia 47 (2010): 219–224.

4. Occupational Safety and Health Administration (OSHA). Best Practices for the Safe Use of Glutaraldehyde in Health Care. 2006.

5. Acosta-Gnass, S.I. and Stempliuk, V.A. Sterilization Manual for Health Centers. Pan American Health Organization, 2009.

6. Jadhav, S. et al. “The Microbial Colonization Profile of Respiratory Devices and the Significance of the Role of Disinfection: A Blinded Study.” Journal of Clinical Diagnostic Research 7 (2013): 1021–1026.

7. Canadian Standards Association (CSA). Decontamination of Reusable Medical Devices. 2008: 1–87.

8. Acosta-Gnass, S.I. and Stempliuk, V.A. Sterilization Manual for Health Centers. Pan American Health Organization, 2009.

9. Barbut, F. et al. “Comparison of the efficacy of a hydrogen peroxide dry-mist disinfection system and sodium hypochlorite solution for eradication of clostridium difficile spores.” Infection Control & Hospital Epidemiology 30 (2009): 507–514.

10. Columbia Patient Safety Branch Ministry of Health. Best Practice Guidelines for the Cleaning, Disinfection and Sterilization of Medical Devices in Health Authorities. 2007.

11. Dorsch, J.A. and Dorsch, S.E. Understanding Anesthesia Equipment. 5th Edn. New Delhi: Lippincott Williams and Wilkins. Wolters Kluwer (India) Pvt. Ltd., 2008. “Cleaning and Sterilization,” pp. 955–1000.

12. Sabir, N. and Ramchandra, V. “Decontamination of Anaesthetic Equipment.” Continuing Education in Anaesthesia, Critical Care & Pain 4 (2004): 103–106.