Application of Asepsis to Sterile Procedures and Operating Theatres

Introduction to Asepsis and Infection Control Principles

Asepsis means the absence of disease-producing microorganisms. In healthcare settings, infection control relies on two distinct approaches: keeping environments clean and actively preventing microbial contamination of susceptible sites. Surgical site infections remain a major challenge in Nigerian hospitals, often prolonging hospital stays and increasing treatment costs. Strict adherence to aseptic practices forms the primary defense against these complications.

Medical Asepsis Versus Surgical Asepsis

• Medical asepsis: Often called clean technique, this practice aims to reduce the number of pathogens and prevent their spread. Examples include handwashing and routine surface cleaning.
• Surgical asepsis: Known as sterile technique, this practice eliminates all microorganisms, both pathogenic and non-pathogenic, including spores. It is mandatory for any procedure penetrating body tissues, such as major operations or catheter insertions.

Design, Zoning, and Environmental Controls in the Operating Theatre

The operating theatre layout is divided into distinct zones to control microbial load. Traffic flow moves progressively from unrestricted areas to restricted areas.

Positive pressure ventilation ensures air flows outward from the operating room into corridors when doors open, preventing contaminated outside air from entering.

Principles and Rules of Sterile Technique

1. Sterile to sterile: A sterile item can only touch another sterile item; contact with a non-sterile surface contaminates it immediately.
2. Doubt means contamination: If the sterility of an item is questionable, consider it contaminated.
3. Edges are unsterile: The edges of a sterile package or barrier are considered non-sterile once opened.
4. Perimeter awareness: Sterile persons must stay within the sterile area and avoid turning their backs on the sterile field.

Preoperative Preparation: Scrubbing, Gowning, and Gloving

Surgical hand scrubbing removes transient flora and reduces resident skin flora on the hands and forearms. Water flows from the fingertips to the elbows so contaminants run downward away from clean areas. Once scrubbed, hands are held higher than the elbows. Closed gloving or open gloving techniques are used to don sterile gloves without touching their outer surfaces.

Preparation and Sterilization of Surgical Instruments

Instruments must undergo thorough decontamination, cleaning, and inspection before sterilization. Autoclaving uses pressurized steam to destroy all microbial life, including bacterial endospores. Chemical indicators and biological spore tests verify that the sterilization cycle reached the required temperature and pressure.

Maintaining the Sterile Field During Procedures

The sterile field is created immediately before the procedure and must be constantly monitored. Only sterile items are placed within this boundary. If a sterile barrier is breached or punctured, the entire field is compromised. Personnel must face the sterile field when passing it and never reach across unsterile areas.

Role of the Scrub and Circulating Nurse in Asepsis Enforcement

• Scrub nurse: Works within the sterile field, handles sterile instruments, and tracks counts of sponges, needles, and instruments with the circulator.
• Circulating nurse: Manages the non-sterile environment, coordinates patient care, opens supplies aseptically, and monitors the entire team for any breaks in sterile technique.

Post-Procedure Decontamination and Waste Management

After surgery, instruments are wiped of gross soil, soaked in enzymatic solutions, and sent for terminal cleaning. Waste is segregated according to safety guidelines: sharps go into puncture-proof containers, infectious waste into colored bin liners, and general waste separately. Proper disposal protects healthcare workers and sanitation staff from injuries and infections.