The essential role of disinfecting ventilators and incubators in preventing nosocomial infections in intensive care and neonatology units

In hospitals, especially in intensive care units (ICUs) and neonatal wards, medical equipment such as incubators and ventilators are vital elements of patient care, but they can also become major sources of healthcare-associated infections if not disinfected properly. This issue is extremely important, considering that infections in the hospital environment can lead to severe complications, including neonatal sepsis or infections with multidrug-resistant germs.

Contamination risks of ventilation equipment

Mechanical ventilation, frequently used in the ICU, presents a high risk of bacterial contamination. Studies have shown that components such as Y-pieces can be contaminated with Staphylococcus aureus in up to 86.7% of cases. Water traps used in ventilator circuits can be a persistent source of Pseudomonas aeruginosa, even after disinfection with 75% alcohol. Furthermore, the contamination rate can peak approximately 8 hours after initial disinfection, which underscores the need for strict and frequent disinfection protocols.¹

Essential procedures for cleaning and disinfecting invasive mechanical ventilators²

The World Health Organization (WHO) clearly emphasizes that respiratory devices, such as mechanical ventilators, must be cleaned, disinfected, and, where applicable, sterilized according to the level of risk and patient contact, in accordance with standard protocols and manufacturer instructions. These measures are essential in preventing the transmission of healthcare-associated infections in intensive care units.

During use on the same patient, single-use breathing circuits should not be changed routinely, as this can disperse contaminated aerosols. It is recommended to use filters at both ends of the ventilator (inspiratory and expiratory), replacing them every 48 hours or sooner in case of increased expiratory resistance. Additionally, daily drainage of water from intake filters and the condensate collection container on the expiratory line is necessary to prevent dangerous liquid accumulation in the ventilation system.

Between patients, the ventilator must undergo a complete cleaning and disinfection process. After disconnecting from the patient, oxygen source, and power supply, all single-use components (circuit, filters, expiratory valves), which are considered infectious waste, must be safely removed. Reusable components, such as flow sensors, respiratory valves, active humidifiers, and expiratory tubing, are transported in closed containers for sterilization or high-level disinfection according to the manufacturer's specifications.

The ventilator itself is first cleaned with detergent by wiping from top to bottom, paying attention to surfaces, the screen, cables, the tray, and hoses. After drying, a compatible disinfectant is applied. It is essential that solutions are prepared in well-ventilated areas and not mixed to avoid dangerous chemical reactions.

Finally, the cleaned equipment is stored in a clean space with a low risk of contamination, ensuring a contact time of at least one minute after applying the disinfectant before it is used for another patient.

Incubators – favorable environments for bacterial growth and a major risk for newborns

Incubators, essential for the care of premature newborns, can become breeding grounds for infection if not maintained correctly. High temperatures (over 34°C) and high humidity (over 60%) favor bacterial multiplication. Also, "cold spots" inside incubators can serve as real sources of bacterial contamination. These conditions have been associated with cases of late-onset neonatal sepsis, a serious complication that endangers the lives of vulnerable newborns.³

Cleaning and disinfecting incubators in neonatal units⁴

Current guidelines recommend that incubators and equipment in neonatal units undergo rigorous cleaning and disinfection procedures, following the manufacturer's instructions and institutional protocols. Cleaning is performed in a clean and well-ventilated space, using products compatible with the equipment materials.

It is essential that external surfaces, especially high-touch areas (handles, locks), be cleaned daily, and humidifiers be maintained with daily replacement of sterile water. Complete cleaning, including disassembling components for thorough sanitization, must be performed periodically depending on equipment usage, and for incubators occupied for more than 7 days, terminal disinfection is recommended at regular intervals.

Responsible staff must be properly trained in cleaning techniques, applying methods such as wiping from top to bottom and using the "S" technique to avoid cross-contamination. Furthermore, strict adherence to hand hygiene, according to World Health Organization recommendations, is crucial for preventing the transmission of infections to newborns.

Cleaned equipment must be stored in dedicated spaces, protected from contamination, to maintain a safe environment until the next use.

Biofilm – an invisible obstacle to effective disinfection

An often underestimated aspect in the control of healthcare-associated infections is the formation of biofilm: a community of microorganisms that attach to a surface and are embedded in a matrix of highly hydrated extracellular polymeric substances (EPS)⁵. Bacteria embedded in biofilm can be up to 1500 times more resistant to the action of biocides than those growing in liquid environments, which makes dry surface disinfection considerably more difficult.⁶ This protection explains why, even after terminal cleaning, persistent residual contamination can exist, especially on hard-to-reach surfaces of ventilators, incubators, and other medical devices.⁷

More serious is the fact that multidrug-resistant germs, such as MRSA, VRE, and MDR Gram-negative bacilli, have the ability to survive in biofilm, which increases the risk of transmitting infections between patients.⁸ Thus, eliminating biofilm requires not just routine disinfection, but specialized protocols and products capable of penetrating its protective structure; otherwise, disinfection remains ineffective.

Exogenous transmission of germs in the ICU and the importance of disinfection

Transmission of multidrug-resistant germs in ICU wards is frequent and often preventable. 59.5% of Pseudomonas aeruginosa infections can be avoided through strict hygiene and disinfection measures.⁹ Also, if a previous patient was colonized with multidrug-resistant bacteria, the risk of the next patient becoming infected increases significantly.¹⁰ Surfaces, as well as mechanical ventilation equipment, are proven vectors in the transmission of these germs.⁹

Recommendations for improving disinfection efficiency

To prevent infections, specialists recommend:

• Disinfecting critical components (ventilator parts, water traps, incubator surfaces) at regular intervals, preferably every 8 hours at most;
• Replacing reusable equipment with single-use devices where possible to limit the risk of cross-contamination;¹⁰
• Regularly testing bacterial sensitivity to biocides to adjust disinfection strategies;¹¹
• Carefully monitoring for the emergence of biofilm and applying dedicated protocols for its removal;
• Strict adherence to hand hygiene before and after handling medical equipment, according to WHO recommendations.

Recommended disinfectants for critical areas

The use of high-level disinfectants that are effective and adapted to field conditions is essential for preventing healthcare-associated infections. These include:

• Oxoklin: Contains 5% peracetic acid, 11% hydrogen peroxide, and 1.5% ethanol. Provides cold chemical sterilization in just 15 minutes. It has bactericidal (including against MRSA and Enterococcus faecium), mycobactericidal, tuberculocidal, levurocidal, fungicidal, sporicidal (including against Clostridium difficile), and virucidal effects. It is active in the presence of organic matter and at low temperatures.

• Peroklin: A high-level detergent-disinfectant formulated with 6% hydrogen peroxide and 0.35% didecyldimethylammonium chloride. Provides high-level disinfection in 60 minutes, with bactericidal (including against MRSA, Acinetobacter baumannii, Klebsiella pneumoniae), mycobactericidal, tuberculocidal, levurocidal, fungicidal, sporicidal (including against Clostridium difficile), and virucidal effects against enveloped viruses. It is non-foaming and active in the presence of organic matter.

Disinfection - one of the most important components of preventing healthcare-associated infections

Prevention of healthcare-associated infections in critical wards begins with the correct choice of disinfectants and rigorous adherence to disinfection protocols. Medical equipment, especially that used in mechanical ventilation and incubators, requires increased attention to reduce bacterial contamination, including with multidrug-resistant germs.

Effective disinfection can no longer be viewed as a simple routine gesture, but must be treated as an essential clinical intervention in prevention, holding the same level of importance as the administration of antibiotics or the implementation of isolation measures. In an epidemiological context dominated by resistant bacteria, any improperly disinfected surface can become the weak link in the chain of infection transmission, thereby endangering the lives of critically ill patients and the safety of medical staff. Therefore, the consistent and correct application of disinfection measures remains one of the most important pillars in protecting health within the hospital environment.

Bibliography

¹Sui Y-S, Wan G-H, Chen Y-W, Ku H-L, Li L-P, Liu C-H, et al. Effectiveness of bacterial disinfectants on surfaces of mechanical ventilator systems. Respir Care. 2012;57(2):250–6.

²WHO - Care, cleaning, disinfection and sterilization of respiratory devices, Health Emergencies programme

³Stoll B. J. et al. 1996. Late-onset sepsis in very low birth weight neonates: a report from the National Institute of Child Health and Human Development Neonatal Research Network. J. Pediatr. 129:63–71.

⁴UK Health Security Agency, Guidance-Good IPC practice for the cleaning and handling of incubators and other equipment in neonatal units, 2025

⁵Herrling M.P, Lackner S., Nirschl N., Horn H., Guthausen G. (2019, 04 23). Chapter Four - Recent NMR/MRI studies of biofilm structures and dynamics. Annual Reports on NMR Spectroscopy, 97

⁶Fux C, Costerton J, Stewart P, Stoodley P. Survival strategies of infectious biofilms. Trends Microbiol. 2005;13(1):34–40.

⁷Vickery K, Deva A, Jacombs A, Allan J, Valente P, Gosbell I. Presence of biofilm containing viable multiresistant organisms despite terminal cleaning on clinical surfaces in an intensive care unit. J Hosp Infect. 2012;80(1):52–5.

⁸Nseir S, Blazejewski C, Lubret R, Wallet F, Courcol R, Durocher A. Risk of acquiring multidrug‐resistant Gram‐negative bacilli from prior room occupants in the intensive care unit. Clin Microbiol Infect. 2011;17(8):1201–8.

⁹ Agodi, A., Barchitta, M., Cipresso, R., Giaquinta, L., Romeo, M. A., & Denaro, C. (2007, 05 15). Pseudomonas aeruginosa carriage, colonization, and infection in ICU patients. Intensive Care Medicine, 33, 1155-1161.

¹⁰ Li, Y.-C., Lin, H.-L., Liao, F.-C., Wang, S.-S., Chang, H.-C., Hsu, H.-F., . . . Wan, G.-H. (2018, 03 16). Potential risk for bacterial contamination in conventional reused ventilator systems and disposable closed ventilator-suction systems. Plos One, 13(3).

¹¹Kelemen, J., Sztermen, M., Dakos, E. K., Budai, J., Katona, J., Szekeressy, Z., . . . Michelisz, F. (2024, 08 30). Complex Infection-Control Measures with Disinfectant Switch Help the Successful Early Control of Carbapenem-Resistant Acinetobacter baumannii Outbreak in Intensive Care Unit. Antibiotics, 13(9).

Photo source: Freepik