Why Clean and Dirty Areas Must Be Separated in Procedure Spaces
Separating clean and dirty areas in procedure spaces is essential to prevent pathogen transmission that leads to healthcare-associated infections, with contaminated surfaces playing a documented role in transmitting MRSA, VRE, C. difficile, Acinetobacter, and norovirus between patients. 1
The Core Principle: Breaking the Chain of Transmission
The fundamental reason for spatial separation is that hospital surfaces frequently harbor healthcare-associated pathogens, and contact with contaminated environments is equally as likely as direct patient contact to contaminate healthcare providers' hands or gloves, leading to patient-to-patient transmission. 1 This creates a critical infection control vulnerability that physical separation directly addresses.
Evidence of Environmental Transmission Risk
- Admission to a room previously occupied by a patient with MRSA, VRE, Acinetobacter, or C. difficile significantly increases the risk for the subsequent patient to acquire that pathogen 1
- Hand-mediated transmission is the major contributing factor to healthcare-associated infections, making environmental contamination a direct threat 2
- Contaminated environmental surfaces and noncritical patient care items play an important role in transmitting several key healthcare-associated pathogens 3
Operational Implementation in Procedure Areas
Personnel Movement Restrictions
Members of the surgical, anesthesia, and neuromonitoring team must limit their movements within the OR and between rooms to prevent exposing clean areas to infectious particulate matter. 2 This requires:
- Placement of a team member outside the operative suite to retrieve necessary equipment 2
- Donning and doffing of PPE within an anteroom to prevent exposure of clean areas to infectious matter from the operating suite 2
- Keeping OR doors closed at all times with clear signage discouraging unnecessary entry 2
Physical Space Design Requirements
Operating rooms should ideally be attached to an anteroom as a mechanism of preventing exposure of clean areas, with negative pressure areas and HEPA filtration for doffing, donning, intubation, and extubation procedures that cause significant aerosolization. 2 The anteroom serves as an essential buffer preventing contamination of adjacent clean areas 2
Equipment and Supply Management
- Surgical specialty-specific equipment should be housed within dedicated procedure rooms to prevent movement of equipment from clean areas to contaminated areas and vice versa 2
- Supplying materials to the OR during surgery should be discouraged, with the scout nurse anticipating needs before the operation starts 2
- Any essential retrieval of equipment should be done by staff outside the OR 2
The "Dirty Case" Protocol
Patients likely to disperse microbes of particular risk should be identified before surgery, scheduled last on operating lists, and managed in designated spaces to minimize transmission risk. 2 When this isn't possible:
- A plenum-ventilated operating theatre requires a minimum of 15 minutes before proceeding to the next case after a "dirty" operation 2
- Post-procedure, the OR must undergo terminal cleaning of all exposed material from ceiling to floor including lighting 2
- All areas where contaminated patients have transited must be carefully sanitized 2
Critical Cleaning and Disinfection Protocols
Between-Case Management
- Appropriate cleaning of operating theatres between all patients must be undertaken 2
- Whenever visible contamination with blood or other body materials exists, the area must be disinfected with sodium hypochlorite (per local protocols) then cleaned with detergent and water 2
- Floors of the operating room should be disinfected at the end of each session 2
High-Touch Surface Priority
Clean and disinfect high-touch surfaces (doorknobs, bed rails, light switches, surfaces in and around toilets) on a more frequent schedule than minimal-touch housekeeping surfaces. 2 This targeted approach addresses the highest-risk transmission points.
Spill Management
- Promptly clean and decontaminate spills of blood or other potentially infectious materials 2
- Use protective equipment during decontamination procedures 2
Common Pitfalls to Avoid
Movement Violations
General traffic in and out of the operating theatre must be kept to a minimum, with doors kept closed to ensure ventilation system efficiency. 2 Personnel present in the OR during surgery must not leave the room 2
Inadequate Waste Handling
- Set up a dedicated container for hazardous medical waste immediately outside the OR to immediately dispose of all contaminated disposable material and PPEs 2
- Containers should be closed and sealed before transfer to collection point 2
- All sharps should be disposed of in a dedicated rigid plastic container 2
Linen Contamination
- All used linen must be handled safely to minimize environmental and staff contamination risk 2
- Used bed linen must be handled with care to reduce release of small fomite particles into the air—linen should be "bagged" by the bed or patient trolley 2
The Evidence Base for Spatial Separation
Improved surface cleaning and disinfection can reduce transmission of MRSA, VRE, C. difficile, Acinetobacter, and norovirus, demonstrating that environmental control measures directly impact infection rates. 1 This validates the entire clean/dirty separation strategy as a fundamental infection prevention measure rather than mere procedural formality.
The separation of clean and dirty areas represents a physical barrier in the chain of pathogen transmission, protecting both the sterile field during procedures and preventing cross-contamination between sequential patients through environmental reservoirs 4