Asepsis and Antisepsis in Surgical Preparation
General Definitions of Asepsis and Antisepsis
General Definition: A combination of physical, chemical, biological, and pharmacological methods designed to remove, inactivate, or destroy pathological germs.
Specific Definitions
Asepsis: Prophylactic measures specifically aimed at preventing the contact of germs with a patient in general, and the surgical wound in particular.
Antisepsis: Curative measures focused on the destruction of germs present in a surgical wound, on the skin, or within the environment.
Sterilization: A critical component of antisepsis, involving the destruction of all forms of germs, including viruses and spores. Its effectiveness can vary depending on the resistance of the microorganisms.
Antisepsis: Chemical Means and Applications
Action: Utilizes chemical substances with either:
Germicidal action: Kills pathogenic microorganisms.
Bacteriostatic action: Inhibits the reproduction or growth of bacteria.
Antiseptic: Applied directly to living tissues.
Disinfectant: Applied to inanimate objects, septic products, and the general environment. Doctors are explicitly cautioned not to disinfect people.
Conditions for a Good Antiseptic / Disinfectant:
Must effectively destroy germs.
Must be friendly or non-damaging to tissues (for antiseptics).
Must be soluble in water or alcohol.
The resulting solution must be stable (e.g., Chloramine dissolved in water at concentration serves as a disinfectant).
Examples of Antiseptic Substances:
Alcohol
Iodine (e.g., Betadine®)
Chlorine (e.g., Sodium Hypochlorite, chloramines)
Hydrogen peroxide
Boric acid (known to stimulate granulation)
Potassium permanganate
Asepsis: Preventing Surgical Wound Contamination
Primary Aim: To prevent the contamination of surgical wounds.
Key Requirements:
Rigorous washing of surgeons' hands and their protection with surgical gloves.
Thorough disinfection of the operating field on the patient.
Complete sterilization of all instruments and materials used during every surgical intervention.
Sterilization Methods
Hot Air Sterilization (Poupinel Oven):
Temperature: Typically operates at temperatures around .
Application: Primarily used for metallic instruments, such as surgical instruments.
Wet Heat Sterilization with Water Vapor Under Pressure (Autoclave):
Temperature: Reaches temperatures around .
Application: Suitable for soft materials (e.g., surgical coats, bandages) and a variety of instruments.
"Cold" Sterilization Methods:
Radiations:
Ultraviolet (UV) Radiation: Used for sterilizing the air in the operating room. Modern operating rooms often incorporate advanced ventilation and air-conditioning systems utilizing UV light.
Gamma Rays: Employed for the industrial-scale sterilization of rubber, plastic, and metal materials that are placed in protective wrappers. This method is common for single-use sanitary materials like syringes, plastic drain pipes, and scalpel blades.
Chemical Substances with Antiseptic Action:
Aldehydes:
Formalin Vapor: Used for sterilization of hospital rooms.
Aldehyde Solutions: Provide quick sterilization for metallic instruments.
Special Solutions: Containing an association of aldehydes, specifically designed for sophisticated instruments such as those used in endoscopy and laparoscopy.
Ethylene Oxide: A gas known for its high capacity to penetrate through materials like rubber, plastic, and paper, making it an effective sterilant for delicate or heat-sensitive items.
Principles of Surgical Preparation
Strict Adherence: Emphasizes the strict enforcement of all rules of asepsis and antisepsis.
Material Preparation: Involves preparing pre-sterilized materials necessary for surgery.
Instrument Selection: Careful choice of appropriate instruments for the specific surgical intervention.
Surgeon's Preparation for Surgery
Pre-Operating Room Conduct:
Avoiding septic maneuvers before entering the operating room (e.g., opening septic collections, performing rectal or vaginal examinations).
In the Operating Room (Attire and Personal Items):
Wearing different scrubs, changing into them within specific designated areas.
Utilizing sterile dressing.
Hands must be free of rings, bracelets, and watches.
Wearing a sterile robe (or at least a washed and ironed one that has not circulated elsewhere in the hospital) and shoes exclusively used in these rooms.
Modern operating rooms are equipped with filters to maintain air quality.
It is recommended to wear a sterile gown shirt or undershirt underneath to absorb sweat.
Proper positioning of a surgical cap and mask.
Hand Washing Procedure for Surgeons:
Preparation: The surgeon is already dressed with a cap and mask.
Water/Soap Activation: Taps for water or soap are activated using elbows, feet, or modern sensors to avoid manual contact.
Washing Technique: Hands are washed from the fingertips up to the elbow with circular movements.
Special Attention: Hands, fingers, and fingernails require particular focus.
Cycles: A sequence of wash-rinse-wash-rinse-wash-rinse is performed.
Duration: Each washing round typically lasts minutes using an antiseptic soap (e.g., BETADINE® soap).
Detailed Washing Steps (Multiple Rounds):
Achieved in rounds, each lasting minutes.
First round: Extends up to the elbow.
Second round: Extends up to the mid-forearm.
Final round: Extends up to the lower third of the forearm.
Focus: Emphasis on fingers and wrists to remove flaky epidermal cells and germs.
Modern Antiseptics: Using substances like Chlorhexidine or povidone iodine can significantly shorten the washing time.
Rinsing: Water flow must be directed from the hand towards the elbow to prevent back-contamination.
Valve Operation: Valves must be operated without using the freshly sterilized hands.
Post-Washing Stance: After washing, hands should be held with elbows below the wrist, ensuring they do not touch anything that is not sterile.
Gowning:
Wearing the sterile gown (robe, coat).
Often, assistance is provided by operating room staff for donning the gown and tying cords.
Gloving:
Care must be taken not to touch the exterior of the gloves during placement.
After the gloves are fitted, hands should be held together above the belt, without touching any part of the robe or body that is not considered sterile.