What is MRSA?
Methicillin-resistant Staphylococcus aureus (MRSA) is a type of bacteria that has become resistant to many antibiotics, including methicillin, penicillin, and other commonly used antibiotics. MRSA can cause a variety of infections, ranging from minor skin infections to more severe infections such as pneumonia, bloodstream infections, and surgical site infections.
There are two main types of MRSA:
Healthcare-associated MRSA (HA-MRSA): This type occurs in medical settings like hospitals and nursing homes. It often affects people with weakened immune systems or those with surgical wounds, intravenous catheters, or other medical devices.
Community-associated MRSA (CA-MRSA): This type occurs in otherwise healthy individuals in the wider community. CA-MRSA often causes skin infections but can also lead to more serious infections.
MRSA is particularly concerning because it is harder to treat than non-resistant Staphylococcus aureus due to its resistance to standard antibiotics. Treatment often requires the use of stronger, more potent antibiotics that may have more side effects or be less readily available.
History of MRSA
Methicillin-resistant Staphylococcus aureus (MRSA) first emerged in the early 1960s. It was first identified in the United Kingdom in 1961, just one year after methicillin, an antibiotic, was introduced to treat penicillin-resistant Staphylococcus aureus infections.
MRSA Precautions in the Operating Theatre
To prevent the spread of MRSA in an operating theatre, stringent infection control measures are essential. Here are some key precautions:
Pre-Operative Measures
Screening: Screen patients for MRSA before surgery, especially those at high risk (e.g., those with a history of MRSA infection, recent hospitalization, or those undergoing elective surgery).
Decolonization: If MRSA is detected, decolonization protocols (e.g., nasal mupirocin and chlorhexidine washes) can be implemented before surgery.
Hand Hygiene: Ensure strict adherence to hand hygiene practices among all healthcare workers, using alcohol-based hand sanitizers or soap and water.
Patient Preparation: Preoperative skin antisepsis with chlorhexidine or another effective antiseptic.
Intra-Operative Measures
Sterile Environment: Maintain a sterile operating environment, ensuring all surgical instruments and surfaces are properly sterilized.
Protective Gear: Use personal protective equipment (PPE) such as sterile gloves, gowns, masks, and caps.
Aseptic Technique: Adhere to strict aseptic techniques during all surgical procedures.
Minimize Traffic: Reduce the number of personnel entering and exiting the operating room to limit contamination.
Dedicated Equipment: Use dedicated surgical instruments and equipment for MRSA-positive patients when possible, or ensure thorough sterilization between uses.
Post-Operative Measures
Isolation: Place MRSA-positive patients in single rooms or cohort them with other MRSA-positive patients to prevent cross-contamination.
Hand Hygiene: Continue to enforce strict hand hygiene protocols after surgery.
Environmental Cleaning: Perform thorough cleaning and disinfection of the operating room and equipment after the procedure, focusing on high-touch surfaces.
Monitoring: Monitor surgical sites for signs of infection and implement prompt intervention if infection is suspected.
Additional Measures
Education and Training: Regularly train and update all operating theatre staff on MRSA protocols and infection prevention measures.
Disinfection Procedures for MRSA
Disinfecting surfaces and equipment contaminated with MRSA involves using appropriate cleaning agents and techniques to ensure thorough decontamination. Here are the steps and recommendations for effectively disinfecting MRSA:
General Guidelines
Personal Protective Equipment (PPE): Wear appropriate PPE, including gloves, gowns, and masks, to protect yourself from exposure.
Cleaning First: Clean surfaces with soap and water or a detergent to remove dirt and organic matter before disinfecting. This step is crucial as organic material can reduce the effectiveness of disinfectants.
Disinfectants
Choose disinfectants that are effective against MRSA. Some recommended options include:
Bleach (Sodium Hypochlorite): A 1:10 to 1:100 dilution of household bleach (5.25% sodium hypochlorite) in water.
Alcohol-Based Solutions: Solutions with at least 70% isopropyl or ethyl alcohol.
Hydrogen Peroxide: At concentrations of 0.5% or higher.
Quaternary Ammonium Compounds (Quats): Effective when used according to manufacturer instructions.
Phenolic Compounds: Suitable for a range of surfaces and effective against MRSA.
EPA-Registered Disinfectants: Use disinfectants registered with the Environmental Protection Agency (EPA) that are labeled as effective against MRSA.
Disinfection Process
Apply Disinfectant: Apply the chosen disinfectant to the surface, ensuring thorough coverage. Follow the manufacturer’s instructions for concentration, contact time, and application method.
Contact Time: Allow the disinfectant to remain on the surface for the recommended contact time to ensure it effectively kills the bacteria. Do not wipe off the disinfectant before the end of the contact time.
Wipe or Rinse: After the contact time, wipe the surface with a clean cloth or rinse with water if necessary, especially if the disinfectant leaves a residue.
Equipment
Reusable Equipment: Disinfect reusable medical equipment according to the manufacturer’s guidelines and infection control policies.
Single-Use Items: Dispose of single-use items appropriately to prevent contamination.
Laundry
Contaminated Linens: Wash contaminated linens and clothing in hot water (at least 160°F) with laundry detergent. Use bleach if the fabric can tolerate it.
Drying: Dry on the highest heat setting compatible with the fabric.
Hand Hygiene
Handwashing: Wash hands thoroughly with soap and water for at least 20 seconds.
Hand Sanitizers: Use alcohol-based hand sanitizers containing at least 60% alcohol if soap and water are not available.
Environmental Cleaning
Routine Cleaning: Implement routine cleaning and disinfection protocols in healthcare settings, homes, and other environments where MRSA may be present.
Spill Response: Clean and disinfect spills of body fluids immediately using appropriate disinfectants and PPE.
Can We Sterilize MRSA-Containing Instruments by Autoclave?
According to my experience, I am 100% sure that MRSA-containing surgical instruments can be sterilized by autoclave if the autoclave is properly performed by following proper guidelines, temperature, and pressure.
Autoclaving
Temperature: 121°C (250°F)
Pressure: 15 psi
Time: 15-20 minutes (depending on the load size and type of material)
Can We Disinfect MRSA-Containing Instruments?
MRSA-containing instruments can be disinfected using appropriate methods to ensure they are safe for use. Here are the steps and methods to effectively disinfect MRSA-contaminated instruments:
Chemical Disinfection
Glutaraldehyde: Use a 2% glutaraldehyde solution, immersing instruments for at least 20 minutes for high-level disinfection.
Hydrogen Peroxide: A 3-6% solution can be used for disinfecting instruments, ensuring adequate contact time as specified by the manufacturer.
Peracetic Acid: Often used in combination with hydrogen peroxide for effective disinfection.
Quaternary Ammonium Compounds (Quats): Effective when used according to manufacturer instructions.
Sodium Hypochlorite: Prepare a solution with a concentration of 0.5% to 1% available chlorine. Use household bleach (5.25% sodium hypochlorite) diluted 1:10 to 1:100 with water.
Ventilation and Drying
When disinfecting the operation theatre, many gases are produced, so ventilation is essential. It is crucial to ensure that the gases are properly ventilated and that the surfaces are thoroughly dried before continuing to use the operation theatre.
Ventilate the Area: After disinfection, ventilate the area to remove chemical fumes and allow surfaces to air dry.
Drying: Ensure that surfaces and equipment are completely dry before reusing or storing them to prevent microbial growth.
How to Disinfect an Anesthesia Machine
Disinfecting an anesthesia machine contaminated with MRSA requires meticulous cleaning and disinfection to ensure it is safe for subsequent use.
Steps to Disinfect an Anesthesia Machine Contaminated with MRSA
Preparation
Personal Protective Equipment (PPE): Wear gloves, gown, mask, and eye protection to protect yourself from exposure to MRSA.
Turn Off and Disconnect: Ensure the anesthesia machine is turned off and disconnected from power sources.
Cleaning
Manual Cleaning: Remove visible debris and organic material by wiping down all accessible surfaces of the anesthesia machine with a cloth or sponge soaked in detergent solution. Pay attention to knobs, switches, screens, and any other high-touch areas.
Dismantle and Clean Components: If possible, dismantle removable components such as breathing circuits, filters, and tubing. Clean these components according to manufacturer guidelines using detergent and water.
Dismantle MRSA-Contaminated Anesthesia Machine Parts: Remove and discard parts like the Bain circuit and soda lime. If discarding is not possible, disinfect them using the following steps:
Disinfection via Spray:
Wear appropriate PPE (Personal Protective Equipment) such as gloves, gown, mask, and eye protection.
Sodium Hypochlorite (Bleach) Spray: Apply a 0.5% to 1% sodium hypochlorite solution using a spray bottle, ensuring thorough coverage of all surfaces. Allow the solution to remain on surfaces for the recommended contact time.
Hydrogen Peroxide Spray: Follow up with a 3-6% hydrogen peroxide solution spray, covering all surfaces of the components. Allow sufficient contact time as specified by the manufacturer.
Apply the Same Disinfection Protocol to Other OT Items: This disinfection protocol can also be applied to other operating theatre (OT) items such as OT tables and trolleys:
Preparation and PPE: Wear appropriate PPE.
Dismantling and Disinfection: Dismantle removable parts if possible and apply the disinfection steps using sodium hypochlorite and hydrogen peroxide.
Manual Cleaning: Wipe down all surfaces with detergent solution.
Drying: Air dry thoroughly.
Reassembly and Inspection: Reassemble and inspect for cleanliness and functionality.
Disinfection
Choose Disinfectant: Select a suitable disinfectant effective against MRSA. Common disinfectants include:
Sodium Hypochlorite (Bleach): Prepare a solution with a concentration of 0.5% to 1% available chlorine.
Hydrogen Peroxide: Use a 3-6% solution.
Quaternary Ammonium Compounds (Quats): Follow manufacturer instructions for use.
Apply Disinfectant: Spray or wipe down all surfaces of the anesthesia machine with the chosen disinfectant, ensuring complete coverage. Use a clean cloth or disposable wipe.
Contact Time: Allow the disinfectant to remain on surfaces for the recommended contact time specified by the manufacturer. This ensures sufficient time for the disinfectant to kill MRSA and other pathogens.
Rinse (If Required): Some disinfectants may require rinsing with sterile or filtered water after the contact time to remove residual chemicals. Follow manufacturer instructions regarding rinsing procedures.
Drying
Air Dry: Allow the anesthesia machine and its components to air dry completely in a well-ventilated area. Ensure adequate ventilation to help dissipate any residual fumes from the disinfectant.
Reassembly and Inspection
Reassemble: Once dry, reassemble all dismantled components of the anesthesia machine according to manufacturer guidelines.
Inspect: Thoroughly inspect the machine to ensure all surfaces are visibly clean and there are no signs of residual contamination or damage.
Post-Disinfection Testing
Consider using biological indicators or swab testing to verify the effectiveness of disinfection, especially in critical healthcare settings.
MRSA Survival in the Operating Theatre Without Disinfection
MRSA can survive on surfaces in an operating theater for varying durations, depending on environmental conditions and the type of surface. Here are some specific findings from research:Kramer et al. (2006) reported that MRSA can survive on inanimate surfaces for 7 days to 7 months.
Otter and French (2009) indicated that MRSA can persist on dry surfaces for days to weeks.
Boyce (2007) highlighted that MRSA can survive for extended periods, up to several months, under certain conditions.
Overall, MRSA can survive for:
7 days to 7 months on various surfaces, emphasizing the importance of regular and thorough disinfection in operating theaters to prevent infection.
References
Kramer A, Schwebke I, Kampf G. “How long do nosocomial pathogens persist on inanimate surfaces? A systematic review.” BMC Infectious Diseases. 2006;6:130.
Otter JA, French GL. “Survival of nosocomial bacteria and spores on surfaces and inactivation by hydrogen peroxide vapor.” Journal of Clinical Microbiology. 2009;47(1):205-207.
Boyce JM. “Environmental contamination makes an important contribution to hospital infection.” Journal of Hospital Infection. 2007;65 Suppl 2:50-54.
Note
Lastly, I want to request that while dealing with MRSA, please follow the proper guidelines mentioned above to ensure the safety of the patient, the patient’s family, and yourself. If we do not follow these guidelines, the patient, the patient’s family, and you could suffer long-term consequences.