Guidelines for infection control in operations

A surgical site infection (SSI) refers to an infection that occurs at the site of surgery in a patient's body. It is one of the most common healthcare-associated infections and can cause significant complications. Several factors contribute to the development of SSIs, and when the infection occurs deep at the surgical site, it can lead to fatal outcomes.

Pathogenic microorganisms typically enter the surgical site during the procedure in the operating room. Therefore, it is essential to implement a well-defined preventive program to minimize SSI risks. These risks are influenced by the patient’s condition at the time of surgery, the type of procedure, the surgical team, and the healthcare facility.

Sources of Surgical Site Infections:

1. Internal Sources:

Most microorganisms responsible for SSIs originate from the patient’s own skin, mucous membranes, or intestines (normal flora). When the skin or mucosal barrier is breached during surgery, bacteria can enter the tissues.

• Gram-positive aerobic cocci (e.g., Staphylococcus) are the most common pathogens.
• In gastrointestinal surgeries or procedures near the anus or groin, infections may involve Gram-negative anaerobic and aerobic bacteria from the intestines.
• Infections in abdominal surgeries often involve Gram-negative bacilli, Enterococcus species, or anaerobic bacteria such as Bacteroides fragilis.

2. External Sources:

External sources of SSI include:

• Surgical staff (especially the surgical team).
• Operating room environment (air, surfaces, and equipment).
• Surgical instruments, devices, and materials used during surgery.
• Airborne Gram-positive bacteria, which frequently cause infections.

Preventing Surgical Site Infections:

• Minimize microbial contamination of the patient’s tissues and sterile surgical instruments.
• Administer prophylactic antibiotics before surgery.
• Ensure proper surgical techniques to reduce contamination.
• Maintain appropriate ventilation in the operating room.
• Optimize patient preparation, including skin disinfection and sterile draping.

Compared to patient-related risk factors, infection control measures such as surgical site preparation, antibiotic timing, and operating room management are easier to control.

Environmental Control in the Operating Suite

Providing a Safe Environment in the Operating Room:

• Separate designated rooms for surgical interventions and other medical activities.
• Control the movement of staff and equipment to minimize contamination.

Location of the Operating Room Suite:

• The operating rooms should be located in a specialized area designed for surgical procedures.
• The suite should be easily accessible from the surgical department, emergency unit, but isolated from the hospital's main corridors.
• Walls and floors should be antistatic and antimicrobial.
• Corners between floors and walls should be rounded to prevent dust and fluid accumulation and facilitate frequent cleaning and disinfection.
• Suspended ceilings should be avoided in operating rooms to minimize gaps where dust can collect. If necessary, long panel ceilings should be used.

Temperature and Humidity Control:

• Temperature and humidity play a crucial role in ensuring the comfort of patients and staff.
• Humidity levels should be maintained at 30–60%.
• Temperature should be kept between 20–24°C, with the operating room at least 1°C lower than adjacent areas to direct airflow outward.

Optimal Ventilation in the Operating Room:

• Positive air pressure ventilation should be maintained in the OR compared to surrounding areas.
• The number of air changes per hour should follow manufacturer recommendations for the air handling units.
• Regular maintenance of air filtration systems is necessary.
• Airflow parameters (temperature, humidity, and pressure) should be recorded before each surgery.

Air Quality Standards in the OR:

• Air change rate: 15–20 air changes per hour, with at least three exchanges using fresh, filtered air.
• High-efficiency air filtration should be used, especially for bone marrow transplants, neurosurgery, and orthopedic procedures.
• Air supply direction: There should be a unidirectional airflow system with air exhaust 20–30 cm above the floor, ensuring no obstructions in front of the air vents.
• Each operating room should have pressure, temperature, and humidity monitors at the entrance.
• Operating room doors should be self-closing to maintain sterility.
• Only essential personnel should be present in the OR to minimize contamination risk.

Infection Prevention in the Operating Room

• Strict adherence to aseptic techniques is crucial.
• Proper hand hygiene based on the surgical procedure.
• Use of personal protective equipment (PPE) appropriate for the procedure.
• Isolation of the surgical site from non-sterile areas.
• Maintaining a sterile field throughout the procedure.

1. Hand Hygiene Before Surgery

Proper surgical hand scrubbing is one of the most effective ways to reduce infection risk.

2. Personal Protective Equipment (PPE) in the Operating Room

• PPE protects patients from microbial contamination from the surgical team’s skin, mucous membranes, and hair.
• It also protects surgical staff from exposure to blood and bodily fluids.

Types of PPE:

• Footwear: Surgical staff should wear closed-toe shoes or boots to protect against spills and sharp instruments.
• Head Covers: Disposable head covers should be used to reduce contamination from hair and scalp cells. Head covers must be worn before putting on clean surgical attire to prevent hair from falling onto sterile clothing.
• Surgical Masks:
• Must cover the nose and mouth completely at all times.
• Should not be reused or placed in pockets.
• Must be replaced if damp or between different procedures.
• High-efficiency masks should be used for airborne infections (e.g., tuberculosis).
• Special masks should be used for staff with beards.
• Eye and Face Protection:
• Goggles or face shields should be worn when splashes of blood or body fluids are expected.
• Surgical Gowns (Gowns):
• Should be made of fluid-resistant material to prevent contamination.
• A disposable plastic apron should be worn under the gown if the fabric is not fluid-resistant.
• Surgical Gloves:
• Must be sterile and properly fitted to prevent microbial transmission.
• Change gloves if contamination is suspected.

Maintaining a Sterile Field

• Use sterile, waterproof drapes around the surgical site.
• Only sterile instruments and equipment should be placed in the sterile field.
• Sterile tools should be handled and opened without contamination.
• Items below the sterile field (e.g., under patient drapes) are considered contaminated.
• Only personnel involved in the procedure should handle sterile instruments.
• The sterile zone of the gown extends from the chest to the waist and 5 cm above the elbows.
• Neck, shoulders, and back areas are not considered sterile.

Disinfectants for Preparing the Patient’s Skin and Hands of the Surgical Team

Antiseptics are used on living tissues to inhibit or destroy microorganisms. They differ from disinfectants, which are used on non-living surfaces.

Guidelines for Using Antiseptics:

• Pour an appropriate amount into a sterile container before use.
• Do not reuse leftover antiseptic solution after patient preparation.
• If antiseptics are stored in large containers, transfer only a small amount for single-use.
• Dispose of unused antiseptics at the end of each shift and clean storage containers before reuse.
• Never leave antiseptic solutions in open containers.