The veterinary surgical asepsis refers to the set of procedures aimed at preventing microbial contamination during surgery. Its correct application reduces complications, ensures recovery, and reflects the quality of veterinary services.
Concept and Classification
Asepsis refers to all measures intended to prevent the entry of microorganisms into the surgical field. It is classified into four main categories:
- Sanitization: reduction of microorganisms to levels considered safe for public health. Example: routine cleaning of floors, walls, and common areas using detergents and low-concentration disinfectants. Contact time: 5–10 minutes.
- Sterilization: complete elimination of microorganisms, including spores. Example: surgical instruments processed in an autoclave.
- Disinfection: significant reduction of microorganisms on inanimate objects. Example: cleaning surgical tables with hypochlorite. Contact time: 5–30 minutes depending on the agent.
- Antisepsis: application of chemical agents to living tissues. Example: preparation of the patient’s skin with chlorhexidine. Contact time: 2–6 minutes depending on the product.
In veterinary practice, these measures are combined: the environment is sanitized, surfaces are disinfected, instruments are sterilized, and the patient’s skin undergoes antisepsis before the incision.
Sanitization
Definition: process intended to reduce the number of microorganisms to levels considered safe, without completely eliminating them.
- Examples: routine cleaning of floors, walls, preparation tables, and common areas using detergents and low-concentration disinfectants.
- Agents used: quaternary ammonium solutions, diluted hypochlorite, hospital-grade detergents.
- Contact time: generally between 5–10 minutes.
Sanitization is the first barrier before disinfection and sterilization, ensuring that the surgical environment remains free from accumulated dirt and microorganisms.
Sterilization
Definition: process that eliminates all forms of microbial life.
- Autoclave (moist heat): 121 °C for 15–20 minutes or 134 °C for 3–5 minutes.
- Dry heat: 160 °C for 120 minutes or 180 °C for 60 minutes.
- Gas (ethylene oxide): requires 6–12 hours of exposure and 24–48 hours of aeration.
- Radiation: used for industrial materials, with exposure times varying according to the manufacturer.
Contact time is critical: incomplete sterilization compromises patient safety.
Disinfection
Definition: reduction of microorganisms on surfaces or objects.
- Alcohols (70%): rapid action within 30 seconds, no residual effect.
- Sodium hypochlorite: action within 5–10 minutes, effective against bacteria and viruses.
- Glutaraldehyde: action within 20–30 minutes, useful for endoscopes.
Disinfection must be performed periodically and contact times must be respected to be effective.
Antisepsis
Definition: application of chemical agents to the skin or mucous membranes.
- 70% alcohol: immediate action within 30 seconds, no residual effect.
- Chlorhexidine: initial action within 2 minutes, with residual effect lasting up to 6 hours.
- Povidone-iodine: action within 2–3 minutes, with residual effect of 1–2 hours.
Proper contact time ensures that the patient’s skin is free of microorganisms before the incision.
Preparation of the Surgical Team
Preparation of the surgical team includes:
- Donning attire: cap first, then mask, boots, and finally the sterile gown.
- Surgical hand scrub: lasts 5–10 minutes. It begins at the hands and progresses toward the forearms, always keeping the hands higher than the elbows.
- Gloving:
- Closed method: hands remain inside the gown until the gloves are donned.
- Open method: hands exit the gown and are placed directly into the gloves.
The procedure must be performed without touching non-sterile surfaces. Team discipline is essential.
Patient Preparation
Patient preparation is critical to reduce cutaneous bacterial flora:
- Trichotomy: wide clipping, at least 10–15 cm around the surgical site.
- Initial washing: with water and neutral soap to remove dirt and grease.
- Antiseptic application: chlorhexidine or povidone-iodine applied in concentric motions, repeated at least twice.
- Positioning: dorsal, lateral, or sternal recumbency depending on the surgery, ensuring comfort and access.
- Surgical draping: placement of sterile drapes to delimit the area and protect the rest of the body.
Strict compliance with each step guarantees patient safety and surgical success.
Conclusion
Veterinary surgical asepsis is a comprehensive process involving the surgical team, the patient, and the hospital environment. Proper application reduces complications, ensures recovery, and reflects the quality of veterinary care.
References
Ocronos – Asepsis and antisepsis in surgical practice.
CEU Repository – Veterinary surgical asepsis.
Vanguardia Veterinaria – Best practices in veterinary surgery.
Hernández, J. Veterinary Surgery: Principles and Techniques. Editorial Médica Panamericana.